Earthen domes and habitats. Villages of Northern Syria by DIDA

Earthen Domes et Habitats Villages of Northern Syria. An architectural tradition shared by East and West

Edizioni ETS

Paths, tracks of explorations, research paths, sometimes tortuous, often crossed, constructed step by step. Knowledge, diversity of knowledge built over time, tacit and explicit, cultural landscapes in the world. Projects, experiments for a future that moves from relationship with the places and interpreted traditions. The series explores architecture and design, tangible and intangible culture in places near and far, on objects and ideas, on knowledge and beliefs. Lands, knowledge, culturally, socially and environmentally sustainable innovation, scenarios of present and future challenges. Sentiers, pistes d’exploration, parcours de recherche, parfois tortueux, souvent entrecroisées, explorés pas après pas. Savoirs, diversités des connaissances façonnées dans le temps, tacites et explicites, paysages culturels du monde. Projets, expérimentations pour un futur bâti sur la spécificité des lieux et l’interprétation des traditions. Cette collection est une enquête sur l’architecture et le design, les cultures matérielles et immatérielles, les lieux proches et lointains, les objets et les idées, les connaissances et les croyances. Territoires, connaissances, innovations soutenables au niveau des cultures, des sociétés et de l’environnement, scénarios des défis présents et futurs. Sentieri, tracce di esplorazioni, percorsi di ricerca, talvolta tortuosi, spesso incrociati, costruiti passo dopo passo. Saperi, diversità di conoscenze costruite nel tempo, tacite ed esplicite, paesaggi culturali del mondo. Progetti, esperimenti per un futuro che muove dal rapporto con luoghi e con tradizioni interpretate. La collana indaga su architettura e design, su culture materiali e immateriali, su luoghi vicini e lontani, su oggetti e su idee, su saperi e credenze. Territori, conoscenze, innovazioni culturalmente, socialmente ed ambientalmente sostenibili, scenari delle sfide presenti e future.

Cover photograph by Luca Lupi

Sentieri Saperi Progetti edit by - sous la direction de - curata da

Giuseppe Lotti - Saverio Mecca

ÂŤWe must find a solution to the hitherto insoluble problem of the clash between the products of industry and the demands of nature and of society. It would be useful to subject technology to the economy and materials of a particular region. In this way the quality and values inherent in the traditional and human response to the environment might be preserved without a loss of the advances of science. Science can be applied to various aspects of our work, while it is at the same time subordinated to philosophy, faith and spiritualityÂť. Hassan Fathy, Architecture for the Poor, 1976

Villages of Northern Syria. An architectural tradition shared by East and West

Earthen Domes and Habitats

Edizioni ETS

European Commission

Education, Audiovisual and Culture Executive Agency (EACEA)

Culture Programme 2000

Coupoles et habitats. Une tradition constructive entre Orient et Occident Contract n. 2007-1134/001-001 CTU COHANT 1st November 2007 – 31st October 2009

This collective work is the fruit of the COUPOLES ET HABITATS project, with the support of the Culture 2000 program of the European Union. The views presented in this publication reflect solely those of its authors and contributors. The European Commission shall not be liable for any act or use based on the information it contains. Scientific Committee Saverio Mecca, University of Florence Fabio Fratini, ICVBC-CNR Vassilis Koniordos, Hellenic Society Michel al-Maqdissi Directorate General of Antiquities and Museums of Syria Camilla Mileto, Polytechnic University of Valencia Patrice Morot-Sir, Ecole d’Avignon Önhan Tunca, University of Liége Editors Saverio Mecca & Letizia Dipasquale, University of Florence

Project Leader University of Florence, Italy

Partnership Directorate General of Antiquities and Museums, Syria

Hellenic Society, Greece

University of Liège, Belgium

Polytechnic University of Valencia, Spain

Ecole d’Avignon, France

Authors University of Florence, Italy: Saverio Mecca, Valentina Bonora, Maddalena Chiellini, Letizia Dipasquale, Natalia Jorquera Silva, Giuseppe Lotti, Alessia Nobile, Dalia Omar Sidik, Silvia Onnis, Mirta Paglini, Elena Peducci, Flavio Ridolfi, Luisa Rovero, Ugo Tonietti, Grazia Tucci Hellenic Society, Greece: Vassilis Koniordos, Maria Arakadaki, Clairy Palyvou, Konstantinos Tokmakidis. Ecole d’Avignon, France: Patrice Morot-Sir, Jean-Jacques Algros Polytechnic University of Valencia, Spain: Fernando Vegas, Camilla Mileto, Valentina Cristini, Adolfo Alonso Durá, Arturo Martínez Boquera, Verónica Llopis Pulido University of Liége, Belgium: Önhan Tunca, Emmanuelle Devaux, Katrien Rutten Institute for the Conservation and Enhancement of Cultural Heritage, CNR, Italy: Fabio Fratini Directorate General of Antiquities and Museums, Damascus, Syria: Bassam Jammous, Michel al-Maqdissi, Laila Alturk, Nazir Awad, Antoine Suleiman, Fadia Abou Sekeh Invited Authors John Hurd, ICOMOS International Scientific Committee for Earthen Architecture, Great Britain Abd Al-Qader Hariri, Aleppo University, Faculty of Architecture, Syria Alexis Castro, Culture Lab, Belgium Mario Cygielman, Superintendence for the Archaeological Heritage of Tuscany, Italy Borut Juvanec, University of Ljubljana, Slovenia Sabina Hajiyeva, Azerbaijan University of Architecture and Construction, Azerbaijan Mohamed Al Dbiyat, Institute Française du Proche-Orient, Damascus, Syria Marion Rivoal, Institute Française du Proche-Orient, Damascus, Syria Mohammed Dello, Directorate of Antiquities and Museums of Aleppo, Syria Photographer: Luca Lupi

CNR – ICVBC, Italy

Photographs: Sicily, Ivan Alicata; Abruzzi, Alessandro De Ruvo Guidance and logistical support: Mohammad Haj Ali, Mohamed Meftah

Culure Lab, Belgium

Graphic Design: Susanna Cerri Graphic, maps and drawings: Letizia Dipasquale, Emmanuelle Devaux, Natalia Jorquera Silva, Silvia Onnis English Review: Ben Birdsall

www.edizioniets.com

EDIZIONI ETS Piazza Carrara 16-19, I-56126 Pisa info@edizioniets.com www.edizioniets.com Distribuzione: PDE ISBN 978-884671XXXX

Photographic documentation: Borut Juvanec, Mohammed Dello, Saverio Mecca, Letizia Dipasquale, Silvia Onnis, Emmanuelle Devaux, Flavio Ridolfi, Fernando Vegas, Nazir Awad Graphic documentation: Borut Juvanec, Mohammed Dello, Valentina Cristini, Sabina Hajiyeva, Maria Arakadaki, Clairy Palyvou, Nazir Awad, Antoine Suleiman, Fadia Abou Sekeh, Mohamed Al Dbiyat, Adolfo Alonso Durá, Arturo Martínez Boquera, Verónica Llopis Pulido, Valentina Bonora, Alessia Nobile, Dalia Omar Sidik, Mirta Paglini, Elena Peducci, Flavio Ridolfi This book is copyrighted material, it is forbidden to make copies or reproduce any of the material herein: no photograph, microfilm, tape, electronic support, disk or other copies allowed. Permission or consent to use material is subject to authorization by Edizioni ETS and the Scientific Editor.

European Commission Education, Audiovisual and Culture Executive Agency Culture Programme 2000

Earthen Domes and Habitats Villages of Northern Syria An architectural tradition shared by East and West

editors Saverio Mecca, Letizia Dipasquale authors Fadia Abou Sekeh, Jean-Jacques Algros, Adolfo Alonso Durá, Maria Arakadaki, Nazir Awad, Valentina Bonora, Alexis Castro, Valentina Cristini, Mario Cygielman, Mohamed Al Dbiyat, Mohammed Dello, Emmanuelle Devaux, Letizia Dipasquale, Fabio Fratini, Sabina Hajiyeva, John Hurd, Bassam Jammous, Natalia Jorquera Silva, Borut Juvanec, Vassilis Koniordos, Verónica Llopis Pulido, Giuseppe Lotti, Michel al-Maqdissi, Arturo Martínez Boquera, Saverio Mecca, Camilla Mileto, Patrice Morot-Sir, Alessia Nobile, Dalia Omar Sidik, Silvia Onnis, Mirta Paglini, Clairy Palyvou, Elena Peducci, Abd Al-Qader Hariri, Flavio Ridolfi, Marion Rivoal, Luisa Rovero, Katrien Rutten, Antoine Suleiman, Konstantinos Tokmakidis, Ugo Tonietti, Grazia Tucci, Önhan Tunca, Fernando Vegas

FOREWORDS

Earthen Domes and Habitats

President of ICOMOS International Scientific Committee for Earthen Architecture, Lincolnshire, Great Britain

Since earth is the world’s most accessible building material, it is no surprise that about one half of humankind live, work or worship in structures made with unfired clay subsoils. As recently as the mid nineteenth century this proportion was significantly larger. Earthen buildings are represented across the globe in a range of forms, styles, and technologies that often contain an intangible tradition that has in many cases been continued through countless generations. The empirical wisdom of the builders, through the ages, has improved earthen building technologies into a sophisticated understanding of the evolution of structures appropriate to local cultural, climatic and even seismic conditions, from which we all have much to study and learn. In recent times the traditions of earthen building have been in some decline as ‘modern’ materials replace traditional systems, partly because of global ‘fashion’ trends, but also because of the search for low maintenance solutions in modern society. Earth is fragile and without proper and regular maintenance, structures decay and disappear, now a worldwide trend. This decline has given urgency to the matter of recording and documenting the many traditional and local typologies and their decoration, their ‘language’ if you will. Earthen traditions are far too valuable to dismiss as irrelevant to the modern world and indeed future generations, they must remain as an example to the caring and ecologically aware architects and builders that are emerging around the world. The importance of the conservation of

the traditions of earthen structures is reflected in a recent UNESCO World Heritage Centre, ten year initiative to deepen research and understanding in these traditions. Often, ensembles of earthen buildings within the macro or micro environment, as they emerge from the mother soil, present cultural landscapes of great beauty and strong complexity. The interaction of the population within this cultural landscape completes the stage, a stage set for the evolution and conservation of cultural tradition and identity. This European Union Project, and this book, have been achieved through a successful co-operation between the University of Florence, several European Universities and Institutions and the General Directorate of Antiquities and Museums in Syria, adds a valuable window, shedding light on the northern Syria tradition of striking domed houses. The ICOMOS Scientific Committee for Earthen Architectural Heritage applauds and encourages such excellent publications in the search for an accurate and useable worldwide typology and description of earthen buildings. This book contributes a great deal to these goals. I thank the Authors and editor and congratulate them, together with all those people who contributed to this book, for the production of a most valuable volume and of great international interest. This book offers an example to others around the world and I hope that this example will be widely replicated as an approach to the documentation of regional earthen buildings.

Earthen Domes and Habitats

Foreword to Earthen Domes and Habitats of North Syria, a shared Heritage between East and West

John Hurd

Earthen Domes and Habitats

Earthen architecture has very deep roots in the Syrian tradition. Excavations of ancient times have shown that in Mureybet, a Neolithic site in the middle valley of the Euphrates, the population used earth in combination with pebbles and elements of wood and straw to build the oldest type of circular houses of the region and probably in the world.1 If we try to see the development of these techniques during this period, which culminates in the site of Jerf el-Ahmar with its community house, we can also attest to the presence of stone sculptures decorating the interior of this type of circular architecture. 2 Similarly, the two cultures Halaf and Obeid, of the sixth and fifth millennia BC, will provide technical development, and it is due to the masterly study published in 1980 by the great scholar of Lyon, Olivier Aurenche, that we can appreciate the architecture of the prehistoric period.3 In the fourth and third millennium BC,4 earthen construction techniques were improved and the use of mud-brick walls and pisè spread almost everywhere among the most famous sites in Syria, such as Habuba Kabira-South5, Tell-Mardikh Ebla6 at Tell Hariri-Mari,7 at Tell-Beydar Nabada.8 This at times magnificent architecture was presented by Jean-Claude 1 2 3 4 5 6 7 8

Cauvin 1978, Aurenche 1980. Stordeur 1998, Stordeur 1999 and Stordeur 2000. Aurenche 1981. See for religious architecture: Tunca 1984. Vallet 1997 Matthiae, Pinnock & Scandone Matthiae (eds) 1995. See the excellent work on this site: Margueron 1995. See most recently: Lebeau & Suleiman (eds) 2007.

Michel Al-Maqdisi

Directorate General of Antiquities and Museums DGAM Ministry of Culture, Damascus, Syria

Margueron in his thesis published over 20 years ago, which has helped to reveal the secrets, and extraordinary techniques for achieving several elements of the building, namely: foundation, use of plaster for the walls, roofs, development of the floors and certain other very important elements.9 We are not aware of the oldest attestation of the domes in this type of architecture, but the available data allows us to visualise the dome structures that have been discovered, dating from the period known as “Halaf”.10 In the third millennium BC the presence of steps inside the rooms and the general shape of the corbelling can confirm that, subsequent to the former technique of the Bronze Age, this method was widely used and developed over several millennia until it took on its most complete shape.11 The discussion on earthen architecture and dome construction is thus becoming evermore fascinating and the several Syrian and European teams mentioned in this volume confirm that this system has a particular presence in our architecture, presenting us with the opportunity to work towards the most effective methods for its conservation.12

Margueron 1982. These are the structures of the type called ‘tholos’, see: Pelon 1976. See for example: Quenet & Souleiman 2003. 12 See especially Tunca 1991 and Bendakir 2008. 9

10 11

Earthen Domes and Habitats

In Syria: earthen architecture, mother architecture

List of References

Earthen Domes and Habitats

Aurenche, O. 1980, ‘Un exemple de l’architecture domestique au VIIIe millénaire, la maison XLVII du Mureybet’, in Jean Margueron (ed.), Le Moyen Euphrate, zone de contact et d’échanges, Leiden, pp. 35-54. Aurenche, O. 1981, La maison orientale, l’architecture du Proche Orient ancien dès origines au milieu du quatrième millénaire, Paris. Bendakir, M. 2008, Architecture de terre en Syrie, une tradition de onze millénaires, Damascus. Cauvin, J. 1978, Les premiers villages de Syrie – Palestine du IXème au VIIème millénaire avant J.-C., Lyon. Cauvin, J. 1979, ‘Les fouilles de Mureybet (1971-1974) et leur signification pour les origines de la sédentarisation au Proche-Orient’, AASOR, 44, pp. 19-48 (Excavations Reports from the Tabqa Dam Project-Euphares Valley, Syria). Lebeau, M. & Souleiman, A. (eds) 2007: Tell Beydar, rapport préliminaire sur les campagnes de fouilles 2000-2002 et les campagnes de restauration architectural 2003-2004, Turnhout. Margueron, J. 1982, Recherches sur les palais mésopotamiens de l’âge du Bronze, Paris. Margueron, J. 1995, Mari, métropole de l’Euphrate au IIIe et au IIe millénaire av. J.C., Paris. Matthiae, P., Pinnock, F. & Scandone Matthiae, G. (eds) 1995: Ebla, alle origini della civiltà urbana, di trent’anni scavi in Siria dell’Università di Roma ‘La Sapienza’, Milan. Pelon, O. 1976, Tholoi, tumuli et cercle funéraire, Paris. Souleiman, A. & Quenet, Ph. 2003, Trois campagnes de fouilles syriennes à Tell Abou Hujeira I (1988-1990), I, le chantier B, architecture et stratigraphie, Damascus. Stordeur, D. 1998, ‘Espace naturel, espace construit à Jerf el-Ahmar sur l’Euphrate’, in Fortin M. & Aurenche O. (eds), Espace naturel, escape habité en Syrie du Nord (10e – 2e millénaire av. J.-C., Quebec-Lyon, pp. 93-103. Stordeur, D. 1999, ‘Organisation de l’espace construit et organisation sociale dans le néolithique de Jerf et-Ahmar (Syrie, Xe –IXe millénaires av. J.-C.)’, in Bream F. & Cleuziou Coudart A. S. (eds), Habitat et société, XIXe Rencontre Internationales d’Archéologie et d’Histoire d’Antibes, pp. 131-149. Stordeur, D. 2000, ‘Avant la ville, l’apport des cultures néolithiques de Syrie’, BEO , LII, pp. 31-52. Tunca, Ö. 1984, L’architecture religieuse protodynastique en Mésopotamie, (Akkadica Supplementum II), Leuven. Tunca, Ö. & al. 1991, Architecture de terre, architecture mère, Liège. Vallet, R. 1997, ‘Habuba Kébira Sud, approche morphologique de l’habitat’, in Castel, C., AlMaqdisi, M. & Villeneuve Br. (eds), Les maisons dans la Syrie antique du IIIe aux débuts de l’Islam, Beyrouth, pp. 105-119.

Earthen Domes and Habitats

Project coordinator, University of Florence, Italy

The chief scientific problem related to vernacular architectures, undervalued for the past century or so on account of the difficulty of managing them from a standardized industrial and commercial point of view, lies in the reconstruction of value chains, knowledge and local production. The process of valorisation of earthen architectural cultures is an exemplary case, started many years ago and sustained by important international committees such as UNESCO and ICOMOS, founded partly on the elicitation of constructional knowledge, in compliance with the original contexts, and partly on the innovation of this knowledge through an evolutionary framework organized on the basis of social, economic, and technical expectations and requirements. The core goal of the ‘Coupoles et habitats’ project1, of which we present the results, is: - to document the unique historical landscape of earthen dome villages in northern Syria that has continued to express the complex relationship between the environment, people and architecture over thousands of years; - to examine the common roots between East and West demonstrated by the astonishing diffusion of corbelled architectural and building culture all over Europe and the Mediterranean; - to experiment and test an interdisciplinary approach to the analysis and valorisation of knowledge systems that we call Vernacular Architectural Heritage. Vernacular Architectural Heritage (VAH) is important for our own future because such architectures are characterized by: Culture 2000, Third Countries : Coupoles Et Habitats, Une tradition constructive entre Orient et Occident. Contract n.2007-1134/001-001 CTU COHANT

- a high level of technical variability and integration in geographical and cultural environments together with their traditionally ecological and effective energy performances, which is of the utmost relevance; - consistent levels of “tacit” and local knowledge, of technical and procedural competence and of information on local materials, resources and practices; - criticism, however, related to the durability (in the chemical and physical sense), to mechanical weakness and seismic vulnerability. Syrian earthen corbelled dome architecture expresses these characteristics at the highest level: the project offers to Syrian and international communities an analysis of its constructional system, based on a deep knowledge of local building culture, on local technical heritage and on experimental research into the physical, energy-related and structural behaviour of ‘earth’, stones, and ‘poor’ wood as building materials. The final goal of the project is, therefore, to increase the perception and consciousness of the value of this local earthen architectural heritage in an effort directed towards the sustainable development of this region. The complexity and the cultural, social and technical variability of Syrian EAH, together with insufficient levels of scientific knowledge of the causeeffect relationships between specific characteristics and total performances, is linked to a decay in the perception of this way of living and its social value, and to the loss of local and ‘tacit’ technical knowledge: the final result is a non-satisfactory qualitative and quantitative model of performances of earthen architecture. The conservation and valorisation of this heritage can be successful only if

Earthen Domes and Habitats

Corbelled earthen dome villages of Syria: from past to sunstainable future

Saverio Mecca

Earthen Domes and Habitats

such architecture is one of the building technologies of the future: we shall safeguard the values of diffused quality in a widespread architectural heritage only if they become a ‘living’ architectural culture. In this sense, even the conservation issue has to be faced through methodologies and tools concerning design and project management. The conscious design of new architectures and heritage conservation requires a combination of specific scientific and experimental knowledge, along with both the local and tacit knowledge systems that are at present dispersed, unconnected and, in some respects, lacking. Insufficient social value and a lack of knowledge is, in fact, at the base of the perceived poorness, inadequacy and unreliability of earthen technology, an ‘old’ material but, nevertheless, an indomitable expression of cultural diversity, variable in relation to the cultural and natural characters of places, capable of being a strategic material for the future of architecture and human settlements. Building in earth: cultural plasticity and sustainability Earth is an essentially original and misunderstood raw material with great potential ranging from its positive environmental/energy ratio, to its admirable capacity to integrate other materials such as stone, wood, brick, lime

and vegetable fibres, etc., capable also of constituting the sole material for whole buildings in climatically and geographically extreme situations. The technique of building with earth developed independently in all areas of economic and cultural development: in Mesopotamia in the Valley of the Tigris and the Euphrates (Syria, Iraq and Iran), in the Valley of the Nile (Egypt), in the Jordan Valley (Palestine and Jordan), in India and China, in Maghreb and Sub-Saharan Africa, in Central America and Peru. In particular, in regions with a hot/dry climate it boasts the considerable advantages of quick manufacture and ease of drying, with good resistance to fire and, when properly protected, even to the elements. It also has the capacity to keep buildings cool in summer and warm in winter through thermal insulation and inertia. Since the first Neolithic civilizations with the development of agriculture, we have seen the beginning of stable architectures in all fertile regions, often with both resources present: the alluvial deposits of clay and sand, and straw from fields of cereal cultivation, which facilitate the production of the most widespread key material in the world: the clay mixture that we call ‘earth’. ‘Earth’ possesses the great capacity to respond to the housing needs of millions of human beings, not only quantitative needs compatible with limited environmental harmony and resources, but also qualitative cultural requirements, as a result of its high cultural ‘plasticity’ and its ability to change and

Earthen Domes and Habitats

adapt in response to variations in the natural and human environment, being an expressive language of identities and differing histories. With fresh attention to the environment, we can return to earth as a new technology of architecture for the twenty-first century. In the most vulnerable regions, earthen building is the most effective and sustainable technology with which to produce volumes of houses and buildings in the short-term, capable of encouraging the development of local resources, materials and craftsmanship, of increasing technical and professional competence, and of reducing the share of imported goods and technologies related to building activities. In this era of globalization there is the definite need to enhance local cultures and earthen architecture, for which we should develop research and testing processes, and investment in the pursuit of knowledge, in order to explore and develop the significant strategic potential of the material, as was the case with reinforced concrete in the twentieth century. The future of earthen architecture Knowledge in the broad sense can therefore be identified as the main resource that can be produced, reproduced and disseminated to trigger the processes of self-development and creativity, training of new paradigms,

Oum Aamoud Seghir

methods and the design tools of human settlements. Research and experimentation are the main fields of international co-operation among Mediterranean countries, being one of the most powerful tools to rebuild such a Mediterranean community that only in recent centuries has been dismantled. The same trends of migration and climate change are accentuating the sense of human community, which, starting from the Mediterranean countries, is involving and integrating peri-Saharan and European cultures. These findings urge us to invest in a wider and deeper knowledge of earthen architecture and of all traditional techniques in general, towards a progressive enhancement of their potential performance, not just those traditional and physical, but also those relating to sustainability, till now insufficiently understood. We need investment in knowledge, in the rebuilding and development of constructional skills, combined with a common language and the sharing of scientific and technical culture regarding earthen construction, not only between technical and professional communities, but also between the peoples of the Mediterranean themselves.

Earthen Domes and Habitats

The results of this European Union Culture 2000 project contain some highly significant and valuable information concerning the earthen domes of Syria and related architecture of the Mediterranean countries. We may be grateful for the efforts of all the Syrian and European partners, headed by the University of Florence, in focusing on the importance of this culture of earthen architecture and the conservation of such knowledge, whilst also playing an important role in preserving and protecting against the loss of this whole heritage. As is well known, earthen architecture existed in Syria many thousands of years ago, and the country has to this day a great wealth of these architectural gems. The project studied contemporaneously the origins of corbelled dome architecture and â&#x20AC;&#x2DC;tholosâ&#x20AC;&#x2122; in the Mediterranean region (Syria, Greece, Etruria, the Near East, Italy and Portugal), and the Syrian earthen corbelled dome architecture of today in its rich variety of history, architecture, building methods, art and traditions, belonging to a deep-rooted custom of Syrian earthen construction. Many factors affect the character and distribution of corbelled earthen domes: geographical, climatic, the localization of building earth and water, traditional, social and economic factors. The geography of Syria has also influenced the distribution of corbelled dome architecture, architectural morphology and building details of different areas, while constructional culture and the structural concept have hardly changed over the different regions in thousands of years. The local words (the project presents also an Arabic glossary of architectural terms, of service to foreign researchers and students studying the architecture of this area) testify to this shared architectural heritage. This project responds to an increasingly important need: the growing necessity to learn from vernacular architecture, especially from earthen domes,

Abd Al-Qader Hariri

Dean of the Faculty of Architecture, Aleppo University, Syria

the techniques and materials, not only to register this information as historical knowledge and archival documentation, and to utilize such data and scientific research to protect this patrimony, but also to design and construct new sustainable buildings using what is natural and local as our forefathers and the ancients did long ago. The necessity of learning and transmitting this knowledge to students of architecture and architects themselves arises from the great responsibility we now have, that of addressing issues of environmental pollution to protect the natural world and local culture by a return towards traditional building materials and production, learning to reuse natural materials and techniques. Our role in these studies (as professors, architects and students) lies in knowing how to apply the best methods and tools for the conservation of earthen architectural heritage, and in knowing how to learn from it practically so as to work directly towards a future architecture in greater equilibrium between humanity and nature. This knowledge requires primarily a full understanding of the benefits of earth as a building material (being fireproof, durable, easy to maintain, and pleasant to work with) on the one hand, and to distinguish its natureand climate-friendly characteristics on the other, since this material is an available, renewable and recyclable resource, non-toxic and emission-free, requiring few transport resources, providing high thermal mass, good insulation properties and low energy costs. Earth as a building material also balances indoor climate, regulates air humidity and maintains comfortable surface temperatures. As this project has done, we need to study and analyze systematically our existing earthen buildings and the heritage of this architectural knowledge in order to arrive at an architecture in the future employing concepts gleaned from this culture, to find a balance between old techniques and new exigencies, between past and future.

Earthen Domes and Habitats

An important new contribution to Syrian architectural heritage

Corbelled dome architecture is a culture and construction technique common to both East and West. In particular, the corbelled domes or “tholos domes” are an ancient construction technique that produced remarkable urban and rural architectural habitats, from an aesthetic and anthropological point of view: thousands of examples of habitats are found all over the Mediterranean region, such as the Trulli of Puglia, the Specchie of Salento (Italy), the Cabanes of Vaucluse (France), the Chozos of Spain and Portugal, the Bombos of Castilla La Mancha, (Spain), the Pinnettas of Sardinia or the Qubbas of Syria. The corbelled dome reflects the common roots of a heritage, both tangible and intangible, a way of life and expertise shown in a cultural diversity that is exemplary of the balance between knowledge, resources, needs and values, that was developed over literally thousands of years. In the Mediterranean region, the architectural culture of corbelled domes is an expression of dry-stone building culture mostly connected to sheeprearing and the related nomadism of shepherds, with only a few exceptions, most notably in Alberobello, Apulia. In Syria, the culture of corbelled domes is an expression of earthen building culture and of semi-nomadic people living in this arid region. While the corbelled domes of the Mediterranean have been documented, until now very few studies have investigated the earthen corbelled domes of Syria.

Culture Lab, Belgium

Saverio Mecca

University of Florence, Italy

Valorise a cultural heritage shared between East and West The first goal is to valorise an architectural heritage ultimately at risk, an architectural culture shared between East and West, providing real evidence of the culture of a people at the origins of the Mediterranean identity, and their cultural diversity. The first action of valorisation is to identify the roots of this culture of construction to which archaeological evidence in Syria, the Aegean Islands and Etruria is testament. Through the documentation the core of the structural knowledge, which enabled people to use such simple resources like clay and limestone and to diffuse it over all the Mediterranean to solve the basic problems of architecture, can be found. The second action is to analyze and characterize the material and immaterial dimensions of the architectural heritage of earthen corbelled dome habitats in Syria The project has been based, therefore, on an interdisciplinary approach towards an in-depth study of local architecture and a representation of architectural knowledge, in other words, to increase specific scientific knowledge through an interdisciplinary scientific research. The scientific research action developed by the project included: • Geographical analysis of the arid region of Syria where the corbelled dome habitats are found • Morphological analysis of the urban structure of villages • Architectural analysis of houses and of domes • High definition modelling 2D/3D in order to document and realize a

Earthen Domes and Habitats

Coupoles et habitats, an EU Culture 2000 project

Alexis Castro

Earthen Domes and Habitats

•

• • •

database supporting technical and mechanical analysis; Characterization of building culture identifying and codifying building elements and building knowledge, the diversity of dome types and construction processes Characterization of the phenomena of degradation of materials by an archaeometric analysis Characterization of mechanical behaviour by structural experiments “in situ” and in the laboratory Analysis of living culture through the interiors of corbelled dome houses.

Contribute to safeguard a cultural landscape and support an effective approach to sustainable conservation of architectural heritage The third action is to support awareness to better understand the cultural value, conserve and protect this endangered world heritage through the promotion of training and awareness initiatives in conjunction with the public authorities, and an exchange of actions, experiences and knowledge between Syrian and European university specialists. Safeguarding vernacular architecture cannot be separated from the grass roots , the lives of the people and their hope of assuring better lives for their children: all strategies and activities of conservation must be tailored to the needs of modern life in a sustainable frame of development. The fourth action is to communicate to Europeans, Syrians and to the whole world the value of this cultural heritage and to disseminate the specific knowledge and skills related to this shared heritage through an exhibition in Europe and Syria, a scientific seminar in Damascus and the publication of this scientific catalogue of the exhibition including the results of research activities. Planned activities The project has been developed through a close cooperation and partnership among researchers of 6 countries, Italy, Syria, France, Belgium, Spain and Greece. The profiles of researchers and technical experts have been complementary in terms of archaeology, architecture, building technology, geomatics and mechanics. The index of the scientific catalogue reflects the structure of the project and the main axes of activities :

Axis 1: State of the art in archaeology and in vernacular architecture A historical and scientific state of the art assessment in archaeology and in vernacular architecture. The archaeological studies have focused on the corbelled dome in the archaeology of the ancient Near East, on the Prehistoric dome architecture in the Aegean and on the tholos tombs of Etruria, to investigate the origins of corbelled dome culture and its diffusion in the Mediterranean region. The vernacular architecture studies have been oriented towards a general overview of corbelled dome architecture in modern times in the Mediterranean region and to a comparative analysis of corbelled domes in the architecture of Spain and Portugal, in France, in Italy and in Greece, and looking further afield to Azerbaijan, identifying the diffusion of a shared architectural culture and its diversity. Axis 2: Original scientific research on architectural heritage Both a field and laboratory research on the corbelled dome villages of the Aleppo region. After an initial mission to select the sites, two missions have been developed for field surveys where several integrated methods and tools have been used by the partners as geomatic methods for a detailed 2D and 3D modelling, also architectural methods for characterising the urban and architectural morphology, either construction techniques, archaeometric methods for characterising the materials and the degradation processes, and mechanical methods for characterising the structural behaviour of earthen domes. Axis 3: Communication and dissemination of results Production of documents devoted to communication and dissemination of the project and awareness promotion of the value of cultural heritage. The strategy of communication is articulated in several coordinated actions: - a scientific and photographic exhibition to be held in Damascus and then in Aleppo (Syria) and in Florence, Thessaloniki, Valencia, and next year in Paris and other main cities (Europe); - a scientific seminar to be held in Damascus as an opening to the exhibition ; - a training seminar to be held in Aleppo at the Faculty of Architecture of the University of Aleppo to promote the documentation, analysis, preservation and enhancement of vernacular architectural heritage, the methods and practices of earthen dome habitat heritage conservation.

Earthen Domes and Habitats

The southeast Mediterranean has a millennia-old history and culture. Being the crossroads of the continents and the sea for different civilizations and religious denominations, the region has acted as a natural link between East and West throughout the centuries. This cultural integrity is unique, pointing back to common historical roots and mutual influences. Thus, cultural corridors recognize no borders, date back to various ages and have been created by diverse civilizations. They start from southern Europe, run through several continents and finish up in Africa. The word ‘vernacular’ was originally used by linguists to mean the ‘native language of a region’ as opposed to a superior (often imposed) language like Latin or Greek. Architectural historians borrowed ‘vernacular’ to mean the native architecture of a certain region. Vernacular architecture is a form of building that is distinctive to the region where it is practised, based on local needs and preferences. It is an aspect of cultural expression rooted to a particular place. Vernacular architecture brings with it an enormous artistic, functional and cultural wealth. This architecture is produced not by specialists, but by the spontaneous and continuing activity of whole peoples with a common heritage, bringing new values to the community experience. This architecture has often been considered as ‘primitive’, but today we all recognize the art-form in it, as a result of human intelligence related to different human modes of life. The skill and knowledge of the anonymous builders presents the larg-

Hellenic Society, Thessaloniki, Greece

est unutilized source of architectural inspiration beyond economic and aesthetic considerations, how to live and how to keep peace with one’s neighbours. Building knowledge in vernacular architecture is often transported by local traditions and groups of technicians, handed down as it is through the generations. The lifestyles of the occupants and the way they use their shelters is of great influence on building forms. The size of family units, who shares these spaces, the way people interact and other cultural considerations ultimately affect the layout and size of these constructions. Social interaction within the family is governed by the separation between the structures in which family members live. Culture also has a great influence on the appearance of vernacular buildings in accordance with local customs and beliefs. Despite the ‘passage’ of different nations, these types of houses have survived almost unaltered up to the present day, still serving the inhabitants well. Vernacular building heritage is important; it is the fundamental expression of the culture of a community, of its relationship with its territory and, at the same time, an expression of the world’s cultural diversity. Vernacular building is the traditional and natural way by which communities house themselves. It is a continuing process including necessary changes and continuous adaptation as a response to social and environmental constraints.

Earthen Domes and Habitats

Vernacular architecture as a cultural heritage shared by East and West

Vassilis Koniordos

Earthen Domes and Habitats

As these buildings and stories show, vernacular heritage constructions are often taken for granted and frequently undervalued. Many of these structures have had close calls and were very nearly demolished. Some hold on to life by a slim thread, ignored and generally forgotten. Vernacular building heritage occupies a central place in the affection and pride of everyone. It has been accepted as a characteristic and attractive product of society. It appears informal, but nevertheless orderly. It is utilitarian, and at the same time possesses interest and beauty. It is a focus of contemporary life, and a record of the history of society. Although it is the work of man, it is also the creation of time. It would be unworthy of the heritage of man if care were not taken to conserve these traditional harmonies, which constitute the core of a personâ&#x20AC;&#x2122;s very existence. The survival of this tradition is threatened worldwide by the forces of economic, cultural and architectural homogenisation. How these forces can be met is a fundamental problem that must be addressed by communities and also by governments, planners, architects, conservationists and by a multidisciplinary group of specialists. They represent a system of cultural values and historical links born out of the cultural exchange and dialogue among communities in the region. These communities are becoming increasingly aware of the need for joint efforts to reveal, conserve, use sustainably and promote the rich cultural heritage of Mediterranean vernacular architecture. A knowledge of vernacular architecture and the necessary initiatives to be taken for its salvage, is a process which unites people to joint actions in order to contribute concretely to the preservation of the cultural and environmental equilibrium which represents substantially a mission of peace and cultural education. Taking into consideration all the above the Project â&#x20AC;&#x153;COUPOLES ET HABITATSâ&#x20AC;? is promoting a research for the valorisation of the common architectural cultural heritage between East and West and the development of an interdisciplinary scientific research for the vernacular architecture focusing on the characteristic inhabited complexes with domes in Syria. The construction of domes represents a common cultural heritage and a constructive method of the larger Mediterranean region. This vernacular architecture of Syria testify the common roots of way of living throughout the region of South Europe till Africa, from Aleppo to Puglia, from Majorca to Sardinia.

Earthen Domes and Habitats

ARCHAELOGY OF CORBELLED DOMES

Earthen Domes and Habitats

Buildings probably covered with domes in the archaeological record As has been mentioned above, excavations uncover generally only the lower part of buildings, so the reconstruction of the roof in the shape of a dome can only be made on the basis of the ground plan. Present traditional houses provided with domes, display a ground plan which is either square or circular. As a result, we can assume that ancient architectural units with a circular or square plan could have been covered with a dome. Fig. 1: Map of Syria and northern Iraq with the sites mentioned in the text. TURKEY Chagar Bazar Tell Sabi Abyad Shams ed-Din Tannira

SYRIA

Nineveh

Arpachiyah

IRAQ

ris Tig

Modern cities Archaeological sites

Kha bur

ALEPPO

es rat ph Eu

Technological evidence in archaeological and iconographical documentation Even though stone is occasionally used, unfired mud brick is the principal building material for ancient Near East architecture. Unfired bricks make their appearance in a modelled form in the Pre-Pottery Neolithic A around 8000 BC. By 7500 BC, during the Pre-Pottery Neolithic B, the first moulded bricks are produced (Sauvage 1998, pp. 87-102). It is this particular material which has lent itself to the construction of arches, vaults and domes up to the present day. The technology of the vault appears to have been quickly mastered in the ancient Near East. Corbelled domes and barrel vaults were used in the construction of subterranean tombs in Ur in Southern Mesopotamia dating to the third millennium BC (Woolley 1934, pp. 228-237; Besenval 1984, pp. 164, pl. 107-108). From this moment on, the building technique is applied rather frequently in the ancient Mesopotamian architecture as it avoids the use of wood, a rare commodity in that region, in the roof structure (Novàk & Schmid 2001). We can therefore consider the use of the vault as the first phase prior to the mastering of the domed building technique. As far as we know, not a single decisive piece of evidence for roofing in the

shape of a dome has been found by excavations in the Near East. This could be the result of coincidence concerning the archaeological finds, but is probably also caused by a lack of careful observation during excavations. We can confirm with almost certainty that the dome was used as a method of roofing in at least certain parts of the ancient Near East. In fact, we can in this respect mention one example of iconographic evidence. A Neo-Assyrian relief, recovered at Nineveh (Fig. 1), dating from the reign of the Assyrian king Sennacherib (704-681 BC), represents a scene of wood transport (Layard 1853, pp. 3, pl. 17; Patterson 1915, pp. 19-20, pl. 119; Besenval 1984, pp. 117-118, pl. 147). In the background several domed buildings are depicted (Fig. 2), the shape of which is very much comparable to those known today.

Balikh

Domes constitute the upper part of buildings. Excavations of structures on Near Eastern sites are, however, frequently limited to the lower parts of walls. Exceptionally, the remains of collapsed superstructures can be recovered from the interior of buildings. The way in which a building could have been roofed is consequently the result of an interpretation of architectural remains in relation to the available technical possibilities. These can be found firstly in the archaeological record. Secondly, ethno-archaeological studies on the traditional architecture of the Near East have led to an increase in the number of possible hypotheses (Aurenche 1992).

University of Liège, Belgium

Earthen Domes and Habitats

The corbelled dome in the archaeology of the ancient Near East

Önhan Tunca Katrien Rutten

part of the structure equipped with a circular plan, a roofing of a corbelled dome was put forward (Fig. 3). Since then, many houses of this type were brought to light in the whole area covered by the Halaf culture, stretching from the Mediterranean to the Iranian plateau including Southeast Anatolia. Amongst the important sites which have produced remains of the Halaf period, we must mention Tell Sabi Abyad on the river Balikh in Syria (Verhoeven & Kranendonk 1996, pp. 61-62, 76-77, fig. 2.5). The reconstruction proposed for the structures with a circular plan of Tell Sabi Abyad is a cropped corbelled dome finished with a flat roof (Fig. 4). A similar roof reconstruction (Fig. 5) is suggested for circular houses at Shams ed-Din Tannira (Seeden 1982, pp. 74-75, fig. 79). Comparable structures are still known in present-day northern Syria. Until recently, these reconstructions have remained rather hypothetical, even though they are based on the technical possibilities acquired during the period concerned and on analogies with traditional modern constructions.

Earthen Domes and Habitats Fig. 2: Relief from the palace of Sennacherib at Nineveh showing the representation of houses with domes (After Patterson 1915, pl. 119).

In the archaeological record, the earliest constructions for which scholars have proposed a reconstruction with a dome-shaped roof date to the Halaf period, which corresponds to one of the latest phases of the Neolithic in the Near East (c. 5900-5300 BC). It concerns houses with a circular ground plan of which the diameter can reach up to six metres and which are sometimes attached to a structure displaying a quadrangular plan. Structures of this type were identified for the first time with certainty at Arpachiyah in Northern Iraq (Mallowan & Rose 1935). They were nominated â&#x20AC;&#x153;tholoiâ&#x20AC;? and for the

Circular structures at Chagar Bazar The evidence gathered during the excavations at Chagar Bazar since 2001, represents an important contribution to the reconstruction of the roofing of Halaf circular houses. Excavations were undertaken between 1935 and 1937 at Chagar Bazar by M. Mallowan (Mallowan 1936). A deep sounding of the tell demonstrated that the site had been occupied throughout the complete Halaf period. Recent excavations, resumed in 1999, confirmed Mallowanâ&#x20AC;&#x2122;s observations, whereas his conclusions were improved upon (Tunca & Baghdo 2006). Since 2001, several structures with a circular plan have been discovered in Area F. The walls in mud bricks were preserved up to several rows, but an important observation was made in the case of two houses: the surface of the upper row of bricks proved to show a slight inclination towards the interior of the structure. This inclination is very likely to correspond to the rows of bricks forming the base of a corbelled dome. More important, nevertheless, were the remains recovered from the interior of a large circular structure discovered in 2006. The diameter of this house measures around six metres. The walls have a thickness of 0.65 metres and are preserved up to 0.80 metres in height. The structure had been destroyed by fire and the complete roofing had collapsed into the interior of the building (Fig. 6). It was possible to detect in the debris a succession of some building materials which originally formed the roof. The top of the debris consisted

Fig. 4: Reconstruction of Halafian circular structures with a flat roof at Tell Sabi Abyad (After Verhoeven & Kranendonk 1996, fig. 2.5).

Earthen Domes and Habitats

Fig. 3: Reconstruction of a Halafian circular structure provided with a corbelled dome at Arpachiyah (After Mallowan & Rose 1935, fig. 8).

Earthen Domes and Habitats

Fig. 5: Reconstruction of a Halafian circular house with a flat roof at Shams ed-Din Tannira (After Seeden 1982, fig. 79)

Conclusion The Halaf examples demonstrate that the technique of the corbelled dome could have been mastered as early as the sixth millennium BC. It is therefore reasonable to assume that this technique was also employed during later periods. The fact that the use of this technique cannot to this day be confirmed by archaeological remains is most likely due to the lack of pertinent observaFig. 6: A Halafian circular structure with the remains of the burned and collapsed roof on Area F at Chagar Bazar (Photo Joint Expedition to Chagar Bazar, 2008).

tion in excavations. One can only hope that future excavations will provide us with clear archaeological evidence for the use of the dome in the ancient Near East. List of References Aurenche, O. 1992, ‘L’habitat dans le Proche Orient ancien et actuel: permanences et convergences’, Ethnoarchéologie: justification, problèmes, limites, (XIIe Rencontres Internationales d’Archéologie et d’Histoire d’Antibes: Actes des Rencontres 17-18-19 octobre 1991), Editions APDCA, Juan-les-Pins, pp. 377-389. Besenval, R. 1984, Technologie de la voûte dans l’Orient ancien, Editions Recherches sur les Civilisations, Paris. Layard, A.H. 1853, The Monuments of Nineveh, II. John Murray, London. Mallowan, M. 1936, ‘The Excavations at Tall Chagar Bazar and an Archaeological Survey of the Habur Region’, Iraq, vol. 3, pp. 1-59. Mallowan, M. & Rose, J.C. 1935, ‘Excavations at Tall Arpachiyah, 1933’, Iraq, vol. 2, pp. 1-178. Novák, M. & Schmid, J. 2001, ‘Zur Problematik von Lehmziegelgewölben’, Baghdader Mitteilungen, vol. 32, pp. 205-253. Patterson, A. 1915, Assyrian Sculptures, K. Kleinmann & Co, Haarlem/London. Sauvage, M. 1998, La brique et sa mise en œuvre en Mésopotamie. Des origines à l’époque achéménide, Editions Recherches sur les Civilisations, Paris. Seeden, H. 1982, ‘Ethnoarchaeological reconstruction of Halafian occupational units at Shams Ed-Din Tannira’, Berytus, vol. 30, pp. 55-95. Tunca, Ö. & Baghdo, A.M. 2006, Chagar Bazar (Syrie) I les sondages préhistoriques (19992001), Peeters, Leuven/Paris/Dudley (MA). Verhoeven, M. & Kranendonk, P. 1996, ‘The Excavations: Stratigraphy and architecture’ in Tell Sabi Abyad. The Late Neolithic Settlement. Report on the Excavations of the University of Amsterdam (1988) and the National Museum of Antiquities Leiden (1991-1993) in Syria, ed. P.M.M.G. Akkermans, Nederlands Historisch-Archeologisch Instituut, Leiden/Istanbul, pp. 25-118. Woolley, C.L. 1934, Ur Excavations II, The Royal Cemetery: a report on the Predynastic and Sargonid graves excavated between 1926 and 1931, Publications of the joint expedition of the British Museum and of the Museum of the University of Pennsylvania to Mesopotamia, New York/Carnegie.

Fig. 7: A circular structure with the remains of a corbelled dome dated to the Middle Bronze Age (c. 18th century BC) on Area I at Chagar Bazar (Photo Joint Expedition to Chagar Bazar, 2009).

Earthen Domes and Habitats

of slabs of mud of about 10 centimetres thick, which doubtless represented the top of the roofing. These slabs were deposited onto a layer of charred thatch. These building materials are similar to those used nowadays in the construction of flat roofs in traditional mud brick architecture. Even though the excavation has not revealed up till now remains of wooden beams, the evidence points towards a building covered with a flat roof. We can therefore imagine the roofing of this circular structure as a combination of a half-corbelled dome finished with a flat roof. The reconstruction proposed for the Halaf houses at Tell Sabi Abyad and Shams ed-Din Tannira finds some confirmation here. However, it remains possible that certain circular houses with a more limited diameter could have been provided with a complete dome. Excavations of the 2009 campaign on Area I revealed a circular structure dated to the Middle Bronze Age (c. 18th century bc). This structure of unfired mud bricks, measuring 4 by 4 meters, is covered with a corbelled dome, partly preserved up to the closing rows of slightly inclined bricks (Fig. 7). Its size and ashy fill points towards a function as a kiln or furnace, but further investigation is necessary to clarify its use and interior construction.

Earthen Domes and Habitats

The architecture that developed in the Aegean islands and on the Greek mainland from earliest times and prevailed throughout the prehistoric era was based on a rectangular plan and a post-and-beam system. Stone was the most popular building material in the rocky islands, but mud bricks were also used in certain regions where clay deposits were available. Timber, finally, played an important role as a means to reinforce the walls, especially in the later Bronze Age periods. The circle and the rectangle There are of course exceptions to this general rule. The all-purpose primordial hut, for example, on a round or elliptical plan, made of perishable materials such as wood and reeds, is a common feature of most human landscapes; this timeless, ephemeral structure is still present in the Greek countryside today. But the real ‘exceptions’, standing out among the rectangular buildings in a very powerful manner, are the domed circular buildings made of stone that appear in the Aegean as early as the end of the third millennium BC. They are almost exclusively funerary in function. The houses of the dead are thus distinguished from those of the living, and death is celebrated through the exclusive use of the circle. The choice of form in architecture is surely not arbitrary. The rectangle is a dynamic form, with distinct orientation and proportions, and may easily evolve into something else by expanding one or more of its sides or through the accretion of more rectangles, both horizontally and vertically. It thus facilitates the construction of an upper floor, present in the Aegean as early as the end of the third millennium BC.1 The circle, on the other hand, has no orientation other than the axis at its centre, a kind of

‘axis mundi’, and the direction of the break of the circle at the entrance; all its parts are equal in relation to the center and it is a passive form in the sense that it cannot easily evolve into something different (when circular units are attached to each other they still retain their autonomy). The circle is indeed a powerful emblematic form in many ways, alluding to archetypal forms such as the cave, the womb and Heaven. Naturally, such interpretations may be challenged as interpretations by our modern minds that should not be projected to a remote past. However, regardless of what the prehistoric peoples of the Aegean were thinking when putting aside the circle for funerary use only, there is no doubt that there was a deliberate act of choice and distinction and it is therefore significant in its own right. Circular buildings of a non-funerary function are not entirely absent in the Aegean, but they are very limited and ambiguous in form. Round structures, for example, are found in the West Courts of the Minoan palaces of Knossos and Phaistos, as well as the public court of the settlement of Pyrgos, all dated to the Middle Bronze Age. They are cylindrical in form, dug underground, and functioned most probably as storage spaces, as kind of silos, though other functions have also been suggested.2 At the palace of Mallia there is a double row of eight round buildings, all of the same diameter (approx. 4 meters) that seem to have had a similar function.3 They differ, however, in that they are built above ground (Fig. 1). Only the lower part of the walls survives, with no indication of a door, and five of them had a central pillar to support the roof. The form of their superstructure is unknown, but it is often assumed that they were domed. It is important to emphasize that this is a unique case of a circular, posCadogan, for example, believes that at least one is a cistern (Cadogan 2006, pp. 447-456). See Tiré & van Effenterre 1983, pp.8-9. Preziosi points out similarities between the Mallian silos and those found in Egypt and the possibility of an influence from Egypt (Preziosi 1983, pp. 108-9).

Upper floors are attested at the Early Cycladic settlement of Scarkos on the Island of Ios (Μαρθαʹ ρη 1997, pp. 362-382) and remained a typical feature of Aegean architecture throughout the Bronze Age.

Hellenic Society, Aristotle University of Thessaloniki, Greece

Earthen Domes and Habitats

Prehistoric dome architecture in the Aegean

Clairy Palyvou

Earthen Domes and Habitats a

section a-b

Fig. 1: The Palace of Mallia, aerial photo. Circular structures (grain silos?) built above ground (bottom left).

Fig. 2: Early Cycladic corbelled graves at Syros (after Tsountas)

sibly early domed, building that is not a tomb. Throughout the Aegean and the Greek mainland, from the earliest periods to the very end of the Bronze Age, it is in funerary architecture that the circle triumphs and with it, most probably, the dome or tholos as it is commonly referred to in Greek. Both words are Greek: ‘dome’ is a house concept, regardless of the form, whereas ‘tholos’ refers to a building with a circular plan, regardless of function.4 The examples known from excavations are numerous and

are presented here in three groups, corresponding to the three cultural entities that prevailed in the Aegean during the Neolithic and the Bronze Age periods. The overview that follows gives an insight into the formal and structural peculiarities of each group but also provides the basis for a final discussion regarding the three main questions that have tantalized scholars and experts in this field: form, structure and diffusion patterns. Function, at least, is the only issue beyond any reasonable doubt.

Liddell H.G. & Scott R.

Early Cylcadic corbelled graves Early Cycladic cemeteries are numerous and though severely plundered comprise the main source of information on this culture.5 Tombs are, as a rule, rectangular or trapezoidal cists built of upright slabs, but on the island of Syros there is a local type of small tomb of roughly circular shape (Fig. 2). They consist of a subterranean pit lined with stones up to a certain height and roofed with a corbelled structure. The opening on the top is closed with a capstone. There is a small doorway and a short entrance passage. There are, however, hardly any well-documented drawings of these structures and the technical descriptions available in the bibliography (mostly preliminary reports) are rather sparse. The examples of this type are few and localized and one may even dispute the concept of a true circular structure altogether, since the lower part is often roughly trapezoidal in shape. However, the use of the corbelling technique as a means to provide a shelter is undisputable and in that sense it is among the earliest attested in the Aegean (around 2300 BC).

5 6 7

See Barber 1987, pp. 74-80. See Branigan 1970. See Cavanagh & Laxton 1982, pp. 65-77.

Earthen Domes and Habitats

The Early, Middle and Late Bronze Age circular tombs in Crete Crete is a very large island and the excavations have brought to light a large amount of cemeteries and tombs. There are two major types of tomb construction, both built above ground: the circular and the rectilinear – the latter has been labeled ‘house tomb’ precisely because of its affinities to house architecture. Circular tombs are concentrated in the southern region of the island, in the Messara plain, and have puzzled scholars for years now as to their complete form and their origin (Fig. 3).6 The building technology applied for the construction of these circular tombs and their overall form is one of the most heated issues in the academic debate, and one that may never be resolved since none has survived intact.7 The walls are founded on the bedrock and consist of field stones and mud plaster (Fig. 4). Larger stones or boulders are placed along the interior face of the wall and wedged with smaller ones (wedging seems to be an important factor for the stability of the structure). In some instances there are small walls perpendicular to the outer face of the wall jutting out not more than a meter. Though they look like buttresses, they

RETAINING WALLS BURIALS

0 0

5m 20m

Fig. 3: The circular tomb at Apesokari, Messara, Crete and its annexes; a hypothetical representation of a domed upper structure (after Hood).

are too thin and flimsy to act as such. In earlier tombs doors often face in an easterly direction and are very low, under one meter. These structures are seldom free-standing; there are annexes attached to the circular building, usually at the eastern side, consisting of a group of rectangular rooms, serving most probably ritual purposes.

Earthen Domes and Habitats

The tombs vary greatly in size. The largest is tomb A at Platanos (18 meters exterior diameter, Fig. 5). In several cases, approx. 30 tombs, the walls survive high enough to show that corbelling was involved, an indication for most scholars that the upper part of the tomb was in the form of a vault. This is further suggested by the large quantity of stones found within the debris of the tomb during excavation (Branigan estimates a volume of 90 cubic meters for a tomb at Kamilari, 7.54 meters in diameter, sufficient to provide a vault). The problem however lies with the larger tombs, such as Platanos A, that tend to have relatively thin walls, in which case a vault would be improbable. It has been suggested that these were covered with a light timber roof supporting brush or reeds. In at least one case, at Kamilari, there is evidence of burnt wood among the debris. For the smaller tombs many scholars believe that they had the form and construction of the Cretan mitata (see M. Arakadaki, this volume). Chronologically, the circular tombs belong to the Middle Bronze Age. Recent finds, however, have changed the picture: the earliest examples date back to the EM I – Krasi, Nea Roumata, Ayia Photia and Archanes. These tombs are earlier than the few Cycladic types discussed above and are all found outside the Messara region. For some scholars they provide a link with the past and they are, in other words, the predecessors of all circular funerary architecture in the Aegean and on the Greek mainland. Branigan, in reassessing the ‘circular arguments’ for the origins of the Messara burial type,8 rules out any influence coming from cultures outside the Aegean, such as the vaulted round houses of Khirokitia in Cyprus, of the Neolithic period. Nearer home, he emphasizes the continuity of the Cretan culture. Evans and Xanthoudides believed that the tombs were built as imitations of the houses of the living (the hut?); but then again, the rectilinear form prevails in Crete throughout its history. Finally, Branigan suggests that the tholos may be an artificial alternative to the natural caves used for burials in the Early Minoan period. As to their function, circular tombs were in use for long periods of time and contain multiple burials, whereas ‘house tombs’, as the term implies, were used for family burials. The question, to my understanding, is why some of the inhabitants of Crete chose to emphasize the difference with the living, whereas others chose to do exactly the opposite by using emphatically a ‘house’ form to shelter their dead. Differences in the attitude 8

See Branigan 1993.

Fig. 4: The circular tomb of Kamilari, Crete. Fig. 5: The cemetery of Platanos, Crete (after Branigan).

10m

towards the dead are differences in ideology and are therefore of great significance. From the circle to the dome: the Late Bronze Age Mycenaean tholos tombs Life on the Greek mainland during the Neolithic and the early periods of the Bronze Age seems to have followed a parallel, though different, trajectory to that of Crete. By the end of the era, following the fatal events

Earthen Domes and Habitats

that ended the prosperous life in the palaces and the settlements of Crete, the people of the mainland, especially Peloponnesus and central Greece, take over power in the Aegean region and beyond. A new era of prosperity begins for the Mycenaean people, based on trade and seafaring that soon expands beyond the territories already explored by the Minoans in the Eastern Mediterranean and, for the first time, towards the West also, as far as Spain. The Mycenaeans have their own architectural traditions, and although they gradually become highly influenced by the Minoan culture they retain their distinct character. The circle is not part of the traditional architectural vocabulary of the mainland, except for funerary practices, this they have in common with the islanders. They also have in common, as do most cultures universally, the omnipresent and timeless hut made of organic materials and based on the circular plan.

Fig. 6: The Lion Tomb: one of the nine tholos tombs in the vicinity of the Mycenaean acropolis.

One of the earliest uses of the circle, before it is used for a true edifice, is in the form of a circular platform, at the cemetery of Lefkadia, dated to the Early Helladic II period (2400-2300 BC).9 The cemetery consists of several such platforms that include cist burials. These were covered over with earth forming tumuli, a burial custom quite popular in the broader area of Southeastern Europe. The construction of tumuli probably continued throughout the Middle Helladic period, though the finds are rather sporadic and not always convincing. During this period however, new types of burial practices appear and by the Late Helladic period, the Mycenaeans had developed a variety of tomb types aside from the cist, such as the shaft grave, the rock9

See Branigan 1975, pp. 37-49.

Earthen Domes and Habitats

peribolos reconstructed upper part outline of reconstructed tholos

trench

retaining wall

section

rock

earthen mound

reconstructed upper part

reconstructed wall identified wall

relieving triangle

outline of reconstructed tholos

retaining wall

subsidence

Stais excavation enclosure wall inside the dromos

section

Fig. 7: The tholos tomb at Thorikos, Attica (after H. Gasche and J. Servais).

cut chamber and, most impressive of all, the tholos tomb, a type that became popular during the period 1500-1300 BC. The first tholoi were excavated by Schliemman in 1876 at Mycenae. It was Wace, however, who dug systematically and studied the nine tombs in the vicinity of the acropolis of Myceneae, between 1920 and 1925 (Fig. 6). He consequently published the first detailed description of these tombs with drawings by Piet de Jong and arranged them chronologically in three types based largely on technological and morphological differences.10 Meanwhile, more tholoi were coming to light and it soon became obvious that the three

types Wace cautiously proposed were of little value11 (Fig. 7). Hood published an overview of the tholos tombs, in 1960.12 Pelonâ&#x20AC;&#x2122;s work, however, published in the late 1970s, is to this date the most comprehensive compilation of the Mycenaean tholoi of the Greek Mainland (he mentions more than 116).13 Scholars dealing with Mycenaean tholoi have been concerned with three main questions: a) their date of construction, b) the technology that ensures their stability and c) the origins of this type of structure. They are also concerned, of course, with burial customs and their social significance. Before we proceed to discuss these issues we shall first attempt a general 11 12

See Wace 1921-23.

For an insight to this matter see: Galanakis 2007, pp. 239-256. See Hood 1960, pp. 166-176. See Pelon 1976.

Earthen Domes and Habitats

Fig. 8: The tomb of Atreus, Mycenae (plan and section by W. Dรถrpfeld).

description of the form and construction of a Mycenaean tholos. Although there are, naturally, many differences among the almost 200 tholoi known to date, they do have several features in common, most remarkably the highly standardized bee-hive shape (Fig. 8). They are all made of local stone (not always clear if dry wall or if it includes some clay binding mortar, though the latter is far more plausible). They consist of a passage that gives access to the tomb proper, dromos, the entrance doorway, stomion, and the main chamber, tholos. They are cut into the rock of a hillside, as a rule, starting with the dromos (6 x 36 meters long in the case of Atreus) and widening immediately after the stomion to create the large circular cavity that will hold the tholos proper (Fig. 9). The length of the dromos varies, but it seems to have been cal-

culated so the level of the lintel at the entrance corresponds more or less to ground level; this facilitates the positioning of the huge and very heavy lintel stones by pulling them into place (the lintel stone at the Treasury of Atreus weighs 120 tons). The construction of the tholos within the cavity of the rock requires an enormous amount of stones. Usually they are rubble or roughly dressed, elongated, with their narrow sides looking inwards and kept tightly in place by smaller stones in the form of wedges. A small number of monumental tholoi are constructed with ashlar stones. Two such tholoi, the Treasury of Atreus and the tomb of Clytemnestra, had ornamental faรงades at the entrance carved in stone. The dome is built in courses (rings) each one slightly projecting inwards (corbelling) and the top is sealed with a large capstone placed over the uppermost ring. That which remains distinctly standard in all the tholoi is the bee-hive shape and the ratio of approximately 1:1 between

projecting above ground and seals the dromos and the stomion (Fig. 12). The tholos tomb is thus virtually hidden under the tumulus. The mound itself and sometimes a marker in the form of an upright slab (stele) on its top are the sole indicators of the material wealth and the technical ingenuity that lies below. Many tholoi still stand more or less intact, but sadly all but four have been looted.

Earthen Domes and Habitats Fig. 9: Views of the interior of the tholos tomb of Atreus, Mycenae.

the inner diameter and the height of the tholos.14 The size of the tholoi varies: they seem to fall into three categories: diameter under 6 meters, between 6 and 10 meters, and over 10 meters. The largest is the tomb of Aigisthos, made of rubble stones (13.95 m), and the Treasury of Atreus made of ashlar (14.5 m). These dimensions are unmatched in the history of technology and were only surpassed when the true dome was invented, many centuries later. A vulnerable point in this construction is the break at the entrance. The doorway is wide and tall and the walls framing the opening are very thick and taper inwards at the upper level (Fig. 12). The lintel consists of one or more large stones. Nevertheless, they can hardly cope with the enormous loads of the masonry above; to solve this problem, the Mycenaeans invented the ‘relieving triangle’ based on the idea of the corbelling (Fig. 10). Such a triangle above the lintel helps divert the loads to the massive walls framing the entrance (Fig.11). The triangular gap is closed with an upright slab or a stone wall.15 A typical feature of all tholos tombs is the earthen mound sealed with a water-proof layer of well-packed clay that covers the part of the stone structure On proportions see: Kamm 2000, pp. 19-71. The Tomb of Aegisthus is an interesting case in this regard. Wace was convinced that it had no relieving triangle and this was strongly embedded in the relevant literature. In 1997, however, during consolidation work on the monument, the triangle was revealed. Galanakis recently discovered in the Evans archive in the Ashmolean Museum unpublished drawings and commentaries by A. Evans and D. Mackenzie, written in 1924, on the existence of a triangle (Galanakis 2007, pp. 249). Actually, this is clearly visible on the inner face of the wall. 14 15

An effective yet elusive structural system Despite the large number of known tholoi and the excellent preservation of many, the structural system that provides their stability and endurance to this day remains an open question. This is due to: the absence of detailed documentation drawings but for a few; the inefficient knowledge of a crucial part of the structure, that of the wall behind the visible interior of the tholos; damage or deformation of the walls in several cases; and the lack of thorough technical knowledge and relevant analytical tools in order to approach this issue in depth. Since the 1980s, however, engineers have joined forces with archaeologists in an effort to understand the structural logic of these magnificent structures that rival our modern technical skill. Tholoi are now examined on purely technical grounds using calculations, computer simulations and structural analysis. Ambiguities, nevertheless, still exist; not so much regarding the method of construction – this, strangely enough, can be described fairly well – as the structural model that keeps these very large tholoi standing to this day, 3,300 years after erection. Two theories have been put forward: the corbelling theory and the horizontal ring theory. The former is more widely accepted.16 According to the corbelling theory, Pelon, Cavanagh-Laxton and others,17 forces work in the vertical. Because the forces operate vertically through gravity there is no need for buttressing devices to counteract horizontal forces; and because the forces operate through compression, corbelling can be achieved with a rubble stone structure. In this case, courses should be horizontal (as seems to be in most tholoi). The impressive standardization of the shape of all the tholoi in the form of a bee-hive is an argument in favour of the corbelling theory, for this shape corresponds well to vertical forces of gravity (Fig. 13). If it were the ring effect, on the other hand, there would have been no need for this standardization. Corbelling, above all, was well known 16 17

For a general discussion on the history of research see Cavanagh & Laxton 1981, pp. 109-111. Cavanagh & Laxton 1981, pp. 109-140. Cavanagh & Laxton 1988, pp. 385-395.

18 Santillo Frizell 1998, pp. 625-631. Santillo Frizell 1997-1998. Santillo Frizell & Santillo 1984, pp. 4552. Santillo Frizell & Santillo 1988, pp. 443-446. Santillo Frizell 1988, pp. 234-235. 19 Mee & Cavanagh 1999, pp. 93-101.

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to the Mycenaeans and was applied to many structures, such as the galleries at Tiryns, the Lion Gate and some bridges still standing. The horizontal ring theory was proposed by Santillo and Santillo Frizell18 and presupposes that the stones are very tightly built and compressed so as to overcome the tendency to fall inwards. Two factors are important in this respect for they add to compression: a) the earth piled over the dome (a standard feature in all tholoi but only for the upper part of the structure since the lower part is built within the rock cavity) and b) the oblique placement of the stones that adds to compression through gravity (a feature rarely attested with certainty because of the lack of visual contact with the back of the wall and the deformations which are common and can be misleading). In the ring effect the entrance (stomion) is a weak point as it introduces a dangerous break to the ring. This problem is overcome by friction provided by the huge masses of masonry framing the entrance. An argument against the ring theory is that far too many tholoi are partially preserved with large parts missing. Had their stability relied on the ring effect they would have collapsed entirely. The structural models described briefly above present issues that can be resolved only through systematic analysis based on safe, adequate and detailed data. Could it be possible, for example, that both theories are correct: the lower part of the tholos, up to the level of the lintel, based mainly on corbelling, and the upper part based on the ring effect? It is clear that the detailed documentation of the largest number possible of tholos tombs â&#x20AC;&#x201C; a documentation that will require experts, since this is a task that involves a large amount of interpretation â&#x20AC;&#x201C; is a matter that needs to be given priority in the future. One thing is certain: the construction of a tholos tomb required the mobilization of considerable resources and expertise that were most probably commanded by the palace, as indicated by tablets dealing with personnel. An attempt to evaluate and calculate such an operation for the largest of all, the Treasury of Atreus, offers an interesting insight into the scale of such technical work.19 Preparation work involved cleaning an area of 3,000 square meters and removing 5,000 tons of soil, an enterprise that required 1,250 man-days. The next stage, quarrying away the bedrock, would produce 3,500 cubic meters of debris (3,000 man-days). 3,000 tons of conglomerate stone were then quarried and transported to the site. The huge lintel, carried by

Fig. 10: The structural function of the relieving triangle (after Frizell and Santillo). Fig. 11: The relieving triangle above the entrance.

Earthen Domes and Habitats Fig. 12: The tholos tomb and the tumulus: an isometric reconstruction (after S. Hood).

sledge by 1000 men, would take two days to transport from even not very far away, and so on. All in all, it is estimated that the operation would require 20,280 man-days, not including specialists for bronze work, carpentry and supervision. If we assume that 30 men worked simultaneously on a daily basis, then the whole operation would have taken at least 2 years to complete. The origins of the Mycenaean tholos The highly sophisticated technology of the Mycenaean tholoi demands an explanation: are they the outcome of a local evolution (in which case there should be some sort of a local predecessor) or are they based on technology imported from outside the Mycenaean world (in which case we should seek for predecessors elsewhere)? Both theories20 have been put forward: the former is based on the earlier tradition of tumuli and grave circles (these are 20

For a general discussion and bibliography on Mycenaean tholoi see Rutter 1993, pp. 745-797.

cist graves set within a circular boundary made of a low stone wall, with no earthen mound on top). Yet, the earliest tholos appears in a region (Messenia) that has no such tradition. The second theory points directly to the circular tombs in Crete, mainly in the Messara region. The relationship between the Mycenaean world and that of Minoan Crete, with a diffusion flow pattern directed from Crete to the mainland, is well attested in many instances. An argument in favour of this view is that the archaeological finds in the earliest tholos tomb at Peristeria, Messenia, show strong connections with Minoan Crete.21 Those who object to this theory emphasize the following points: a) there is a large chronological gap between the two, though it now appears that circular tombs were still used (if not built) in Crete when the first Mycenaean tholoi were constructed; b) the Cretan tombs were built above ground whereas the Mycenaean are largely underground. New findings, however, show that this rule has a few exceptions; c) in Crete there are no earthen tumuli, no entrance corridors, the entrance tends to be characteristically small, and so on. A serious drawback to this comparison is the fact that the Cretan circular tombs are badly preserved, which makes it difficult to conclude with certainty on their upper form and structure. On the other hand, the very fact that they have all collapsed, although smaller than the Mycenaean, may be taken as an indication that the structural model differed. The most common theory, however, combines the traditions of the two places: the Mycenaean tholos may represent the merging of a mainland tradition of burial below ground in pits, cists, and small chambers set into a low round tumulus, and a Minoan tradition of burial above ground in large circular tomb chambers with corbelled side walls. However, even if the form and the main structural elements have much in common, the structural ingenuity of the Mycenaean tholos in all its details is surely a local achievement. A final note regarding the quest for origins, is that they go back to the first circular tombs ever to appear in the Aegean region. Such a question can never really be resolved; forms and technology travel around among people in close contact, and engravings produce endless hybrids. Moreover, people can just as well come up with similar ideas and techniques on their own. The Ιακωβίδης 1966, pp. 98-111. In the Peloponnese, in the region of Messenia, a number of tombs cut in the rock – known as rock cut chambers – were found imitating the characteristic bee-hive shape as well as other details of the tholos tombs. This is also the area were the earliest tholos tomb is attested, around 1,600 BC, at Peristeria. The tomb has yielded archaeological finds that relate the owner of the tomb to Minoan Crete.

inhabitants of the Aegean and the Greek mainland always built kilns and granaries of a similar form and therefore had acquired a relevant sense of the stability of the dome, albeit on a much smaller scale. This ‘diffusion anxiety syndrome’, as I have labelled it, need not exhaust us. What is interesting, to my understanding, is the almost exclusive and recurrent use of the circle for funerary architecture. Some believe that this refers to the primordial form of a ‘house’, the circular hut (why not the cave also then?).22 Somehow, I do not find this so convincing for the rectangle was attached to the idea of the house just as strongly and just as early (see for example, the ‘house-tombs’ in Crete, built at the same time as the circular ones in other parts of the island). It is the symbolic power of the circle and the dome as forms per se that can better explain such a choice along with the ‘exclusiveness’ of the use of this shape for funerary practice. Such a connotation is of a far more abstract nature, but man, after all, is primarily a maker of symbols.

22 Baldwin Smith 1951. See also Flannery 2002, pp. 417-433. According to latest research, sedentary life in many parts of the ancient world began with settlements of circular huts like those of the preceramic Near East.

Earthen Domes and Habitats

Fig. 13: Checking the bee-hive shape during construction (after Cavanagh and Laxton).

List of References Baldwin Smith E. 1951, The Dome: A Study in the History of Ideas, Princeton University Press. Barber, R.L.N. 1987, The Cyclades in the Bronze Age, London, pp. 74-80. Branigan, K. 1970, The Tombs of Mesara. A Study of Funerary Architecture and Ritual in Southern Crete, 2800-1700 B.C., London. Branigan, K. 1993, Dancing With Death. Life and Death in Southern Crete c. 3000-2000 B.C., Amsterdam. Branigan, K. 1975, ‘The Round Graves of Lefkas Reconsidered, BSA 70, pp. 37-49. Cadogan, G., ‘Water Management in Minoan Crete, Greece: The Two Cisterns of one Middle Bronze Age Settlement’, in Angelakis A.N. & Koutsoyiannis D. (eds) 2006, Water and Wastewater Technologies in Ancient Civilizations, Iraklio, pp. 447-456. Cavanagh, W.G. & Laxton R.R. 1981, ‘The Structural Mechanics of the Mycenaean Tholos Tomb’, BSA 76, pp. 109-111. Cavanagh, W.G. & Laxton R.R. 1981, ‘The Structural Mechanics of the Mycenaean Tholos Tomb’, BSA 76, pp. 109-140. Cavanagh, W.G. & Laxton R.R., ‘Problem Solving and the Architecture of Tholos Tombs’, in French E.B & Wardle K.A. (eds) 1988, Problems in Greek Prehistory, Bristol, pp. 385-395. Cavanagh, W.G. & Laxton R.R. 1982, ‘Corbel vaulting in the late Minoan Tholos Tombs of Crete’, BSA 77, pp. 65-77. Flannery K.V. 2002, ‘The Origins of the Village Revisited: From Nuclear to Extended Households’, American Antiquity 67:3, pp. 417-433. Galanakis, Y. 2007, The construction of the Aegisthus Tholos Tomb at Mycenae and the Helladic Heresy, BSA 102, pp. 239-256. Hood, S. 1960, ‘Tholos Tombs of the Aegean’, Antiquity 34, pp. 166-176. Kamm, W. 2000, ‘Mykeniscke Kuppelgräber: die Entsschlüsselung der Bauentwürfe’, AM 115, pp. 19-71. Ιακωβίδης, Σ. 1966, ‘Περί του σχήματος των λαξευτών τάφων εις τα Βολιμίδια Μεσσηνίας’, Χαριστήριον εις A.K.Ορλάνδον, Athens, pp. 98-111. Liddell, H.G., Scott, R., Jones, H.S. & McKenzie, R. 1996, A Greek and English Lexicon, Ninth edition, Clarendon Press, Oxford Μαρθάρη, M., ‘Από τον Σκάρκο στην Πολιόχνη’, in Doumas Chr.G. & La Rosa V. (eds) 1997, Η Πολιόχνη και η Πρώιμη Εποχή του Χαλκού στο Βόρειο Αιγαίο, Athens, pp. 362-382. Mee C.B. & Cavanagh W.G. 1999, ‘Building the Treasury of Atreas’, Aegaeum 20, pp. 93-101. Pelon, O. 1976, Tholoi, tumuli et cercles funéraires, Paris. Preziosi, D. 1983, Minoan Archtectural Design, n.174, 175, Berlin, pp. 108-9. Rutter J. B. 1993, ‘Review of Aegean Prehistory II: The Prepalatial Bronze Age of the Southern and Central Greek Mainland’, American Journal of Archaeology 97:4, pp. 745-797. Santillo Frizell, B. 1998, ‘Monumental building and propaganda at Mycenae’, Proceedings of the 1st International Conference on Ancient Greek Technology, Thessaloniki, pp. 625-631. Santillo Frizell, B. 1997-1998, ‘Monumental building at Mycenae: its function and audience’, Opuscula Atheniensia 22-23. Santillo Frizell, B. & Santillo, R., ‘The Construction and Structural Behaviour of the Mycenaean Tholos Tomb’, Opuscula Atheniensia 15:4 (1984) 45-52. Santillo Frizell B. & Santillo R. 1988, ‘The Mycenaean Tholos – A False Cupola?’ in French E.B & Wardle K.A. (eds) 1988, Problems in Greek Prehistory, Bristol, pp. 443-446. Santillo Frizell B. 1988, ‘The autonomous development of dry masonry domes in the Mediterranean area’, AJA 92, pp. 234-235. Tiré, C. & van Effenterre H. 1983, Guide des fouilles Françaises en Crète, Paris, pp.8-9. Wace, A. J. B. 1921-23, ‘Excavations at Mycenae. The Tholos Tombs’, BSA 25.

Earthen Domes and Habitats Populonia, Tomb of the Chariots, external views of the tumulus

Superintendence for the Archaeological Heritage of Tuscany, Italy

The Etruria of the first millennium bc saw the influence exerted by civilizations occurring in the eastern basin of the Mediterranean becoming increasingly pronounced in funerary architecture, making it one of the most interesting regions of the Mediterranean (Fig.1) in terms of the relationship between East and West. It was previously assumed that Etruscan architecture was influenced by domed roofs known in the megalithic period, affecting already the eneolithic period and various Mediterranean cultures in later ages, until the nuraghe of Sardinia and Corsica (Figs. 2-3) and the tumuli1 of Mycenaean Greece as described in the Homeric poems and well known archaeologically (see before Clairy Palyvou, Prehistoric dome architecture in the Aegean). These influences seem, however, no longer to have any foundation and it belongs instead to a distinct tradition (Karageorghis 1967, pp. 121 ss.), although a part of the scientific community does opt for a direct influence being exercised by the people of Corsica and Sardinia on the technical use of the shell of tumulus tombs, and, in more general terms, on the idea of stone architecture (Colonna 2000, pp. 255 ss.) with rooms covered by a dome or pseudo-dome. The tumulus tombs The case of a series of chamber tombs at Populonia (Figs. 3 and 4) dating from the end of the 9th to the 8th century bc is emblematic already in the first Iron Age (9th-8th century bc) in a comprehensive view of incinerations characterizing a large part of the burials of the Italian peninsula. Urns are placed within wells: the tombs are constructed on an elliptical or almost circular plan (with a pseudo-dome made of limestone slabs arranged in jutting rows and set on the floor of the cell) and a dromos bordered by stone walls (Bartoloni G. 2000, pp. 19 ss.). The architectural allusion to the cabin is obvi1

Tumulus is mound and the plural tumuli is mounds

Fig. 1: Map of Etrurian sites

Earthen Domes and Habitats

Tholos tombs in Etruria

Mario Cygielman

sistemare

Fig. 2: Tholos of the tower of the ancient Nuraghe Palmavera

Earthen Domes and Habitats

Fig. 3: Populonia, Poggio alle Granate, chamber tomb del raggio lunato di bronzo

Fig. 4: Populonia, Poggio alle Granate, tomb Cmera 1

sistemare

Fig. 5: Hut urns from Vetulonia and Tarquinia (from Rasenna)

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ous: in the same way in some southern communities of Lazio until Vetulonia, high ranking personalities were choosing cabin huts (Fig. 5) to deposit the ashes of the deceased, (Bartoloni G. 1987) in Populonia stone buildings mirroring royal houses were used. The earliest examples In Etruria the tumuli are, from the 8th century bc, the most widespread form of tomb, designed to fill pit tombs, becoming actual semata (indicating marks). These monumental forms were the most common type of burial in Anatolia from the 8th century bc onwards, as the discoveries made in Frigia in recent decades seem now to suggest. In Anatolia this kind of structure was a genuine innovation compared to previously: if the model of the chamber tomb can be found earlier in the Urartic area, the tumulus as a sema, visible from all over the surrounding territory, is the real ideological innovation of this architecture. We may understand their spread and the need to show the ‘kingship’ of the deceased through this model. The so-called ‘Midas Mound’ in Gordion, a tumulus 50 meters high and 250 meters in diameter, is an example. Without crepidine2 and entrance dromos, this enormous mound, restrained by radial walls, covered a small burial chamber, off-center to discourage attempts at intrusion. The burial chamber, built for a single depositional event, given the impossibility of reopening, was made of wood. In the architecture of the first millennium bc these tumuli marked the beginning of a new concept of construction in the eastern Mediterranean basin which was not slow in spreading west, although at present it is not possible to make direct comparisons between Phrygian and Etruscan tombs. The ‘orientalizing’ period The transformations taking place in Italy between the end of the Iron Age (9th-8th century bc) and the period of splendor that characterizes the 7th cen-

The crepìdine (krepis) is an element of classical architecture. In general indicates the basement or the plinth of a building (eg a greek temple). You may get the crepidine under an altar, a platform or even the simple step of a sidewalk can be called ‘crepidine’.

Fig. 6: Cerveteri, necropolis of Banditaccia, Tumulus del Colonnello

tury bc, conventionally defined in Etruria under the term ‘orientalizing’, open the doors to new contacts with Greece and, above all, with the people of the nearby eastern Mediterranean. The emporiums and ports of Syria and Cilicia (Al Mina, Tell Sukas, Tarsus) suffered a setback in the second half of the 8th century bc after the conquest of Palestine, Syria and Cilicia by the Assyrians. Phoenician merchants and sailors of Eubea sought new markets and new areas to exercise their trades and for the supply of metals in particular.

Fig. 7: Cerveteri, necropolis of Banditaccia, Tumulus II

Fig. 8: Vetulonia, Tomb of Diavolino II, plan (from Buffer 2000)

Earthen Domes and Habitats Fig. 9: Vetulonia, Tomb of Diavolino II after the restoration Fig. 10: Vetulonia, tomb of Diavolino II, detail of corner pendentives (before restoration) Fig. 11: Vetulonia Tomb of Diavolino II Fig. 12: Vetulonia, Tomb of Diavolino II, roofed dromos

While the western routes traveled by the Phoenicians appear to follow the North African and Sardinian coasts as far as the Iberian and the Atlantic coasts, with regard to the control of sources of metals, those of the Eubean people were oriented to the Tyrrhenian coast of southern Italy and southern Etruria. The new funeral rituals which flowed into Etruria, and to several Italic communities from contact with those people coming from the Near East and Greece, determined the requirement of enlarging tombs in new and wider spaces with a functional organization for the deposition of rich and heavy funerary objects. Heroic Homeric funeral rituals are assimilated as the most convenient indicators of the rank of the deceased as ‘hero’, while new symposia forms are also highlighted by the presence of the Greek tradition in funerary pottery.

Certainly Cerveteri with its necropolis of Banditaccia constitutes a privileged point of observation for these new styles. Here, beside the modest burial mound with a pit or chamber tomb, distinctive of the area of Laghetto, we can find large multi-generation mounds with very elaborate forms containing up to four chamber tombs. With the old ‘orientalizing’ period (end of 8th century bc) these changes result in the provision of some mounds with pseudo-chamber and chamber tombs. So begins what is known as ‘funerary architecture’, characterized by its own needs and techniques, which go to make up a manner of counter architecture parallel to the urban, and indeed often more important in terms of commitment and expenditure. The chamber tomb is primarily individual, as was usual for pit tombs, then became ‘dual’ to accommodate the remains of pater and mater familias and later multiple, for a long time reserved for a relatively small number of consanguineous relations. A practical entrance, although sealed by stone slabs, facilitated reuse. The oldest tombs have the appearance of larger or smaller rectangular or square pits, with rounded corners, recessed into the ground and covered with masonry blocks jutting out gradually to build a pseudo-vault. In the pseudo-chambers the use of a wooden floor boarding is frequent. However, subsequent developments seem to be influenced by the type of coverage: the pseudo-vault tends to extend the internal space by becom-

Earthen Domes and Habitats

ing a sort of corridor: The most famous of these is in the Regolini Galassi tomb at Cerveteri. A roof made of stones and earth to consolidate the elements, and also to build up a sort of sema or monumentum, is a regular feature. The morphology of the land of southern Etruria allowed the building of sepulchral spaces by excavating into the soft rock to make underground chambers, which do not differ in form and section to those actually built or half-built. This kind of architecture is established early on in southern Etruscan centers such as Cerveteri, already at beginning of the 7th century bc, adopting elaborate boundaries outside the tumulus, the crepidine, with frames carved into the soft tufo (tufa) as in the necropolis of Banditaccia in the Tumulus of the Colonnello (Fig. 6) or in the Tumulus II (Fig. 7). To date, this is the most ancient architectural stone decoration known on the Italian peninsula, predating in ancient times even the tombs of contemporary Greece and Anatolia. We may make an apt comparison with the stone bases of wooden columns in Zinçirli or Tell Taynat in northern Syria, if we accept, as the scientific community is doing, that such models arrived in Etruria and firstly in Cerveteri through that flow of workers arriving in Etruria after the Levantine diaspora of peoples (Phoenicians, Syrians, Cypriots, Anatolian), who were pushed west by the Assyrian invasion of Sargon II (722-705 bc). These workers were responsible for not only the architectural innovations, but also for the instigation of the earliest monumental Etruscan statuary. In this innovative mix of experience coming from the Near East we must remember the contribution provided by these people even in the artistic productions of luxury items (toreutics, metallotechnics, jewelry, etc.), so appreciated by the new Etruscan social group of «princes» who modeled their way of life on the eastern Satraps. Only in Etruscan territory have these architectural elements been so well adapted to the original structure of the mounds: the arch doors, which are common in entrances of tombs of the ancient and medium Orientalizing period, drew inspiration not from the tradition of the First Iron Age but from earthen masonry structures in the area of northern Syria. If the impetus for the creation of these monuments seems to come from the East, that which is typically Etruscan remains the adaptation to the monumental structure of the specific spaces of religion ; a possible example being the kind of podium attached to the mound as a rampant arch for surmounting the perimeter ditch, acting as access to a platform for acts of worship (Fig. 7).

Earthen Domes and Habitats

The constructed mound These architectures, the expression of such aristocratic groups at the head of the orientalizing wave of culture, transmigrate at the middle of the 7th century bc from southern Etruria to the north, especially to Vetulonia (Figs. 8-9) and Populonia, where the first small mounds of the Villanovian age are to be found and the wholly built mound was constructed. The exclusively square plan represents a rationalization of previous curvilinear or rectangular designs, gaining useful space particularly after the adoption of the ritual of inhumation. The roof remains a pseudo-dome with a system of false pendentives (Fig. 10), which recalls the adaptation from the testudo roof moving from ovalshaped structures to the rectangular. In Vetulonia (Fig. 12), where we can see the first monumentalizing of this architectural type, a central pillar was used to support the closure slab of the dome, a solution statically not essential, which seems to have been suggested by the central furca of huts. Other special features are the location of the grave in the center of the mound with a single chamber, rarely accompanied by cells, on a dromos with a plain roof tunnel, and an outer closing stone slab as for the chamber (Fig. 11). The walls of the chamber (Tomb of Diavolino II and upper Tomb of Pietrera) are made from small square sheets connected to the pseudo-vault, made from jutting out slabs through corner pendentives to discharge the weight. Inside the room there were stone funerary beds with decorated legs in the most elaborate form in the tombs of high-ranking personalities such as that of Pietrera in Vetulonia, which is also known for the series of eight stone statues most likely representing the ancestors of the family and spread along the dromos. It must be noted that in this tomb the older grave, the lower, collapsed for some unknown reason a few decades after its construction in the mid-7th century bc and was reconstructed on top using different materials, omitting the creation of a central pillar, as is always the case in the mounds of Populonia. In the latter place, the size of the tombs is much more modest, but made with care using panchina or alberese (local limestone), in the domes and exposed parts (Figs. 13-17). The cap is not accessible and, due to the absence of a podium, a pronounced overhanging stone eave (Fig. 15) is developed for the outflow of rain. The access to the dromos is not hidden, but shown by a projection of the tamburo

Earthen Domes and Habitats

or by the interruption of the paved sidewalk that surrounds the base of the mound (Fig. 14). The pavement can also be identified as a symbolic threshold to the house of the dead, as in the ditch in the tumuli of Cerveteri. The door of the dromos is the focal point of the monument, marked by a paved square area before the projection of the tumulus as that of Tomb of Pissidi Cilindriche (Fig. 16) or by the two great pillars at both sides of the door, as in the tomb of Flabelli. Little wonder then if the use of the chamber is maintained for several generations through a rigorous identification of the tumulus and of the tomb inside. In the context of relations between East and West it does not seem misleading to recall the cenotaph of Menekrate on the Island of Corfu, dating from the end of the 7th century bc, that recalls very closely the shape and dimensions of architectures in Populonia. Even though we still do not have wide archaeological evidence, the environment of Anatolia and in particular the extensive royal cemetery of Bin Tepe around Sardis, the capital of Lydia, offers suggestions for further contact with the Etruscan funerary architecture of the end of the 7th century bc. Cerveteri is again a point of observation for the phenomenon: architectural styles develop in such distant areas at the late 7th century bc and transmigrate with workers from Ionia, perhaps from Sardis itself, in the Etruscan area: we can observe marked similarities between the two environments highlighted by the use of elaborate crepidini built with limestone blocks and toro on top, strongly related, for example, to the top of the great Tumulus of Sorbo at Cerveteri. It is noteworthy how in Roselle, an Etruscan settlement, at the middle 7th century bc at the confluence of two hills, where later a Roman Forum was to rise, there is a unique complex of houses, interpreted as a ceremonial and political center of the community, consisting of a building with a double fence built with bricks and raw clay resting on a beaten clay layer. The main building has a circular chamber, externally rectangular and internally circular (diameter 4.5 meters), with a bench and a threshold. The inward slope of the walls and the definite absence of tiles seems to confirm the hypothesis by some scholars that the roof was covered by a brick pseudo-dome finished with litter or tablets, perhaps supported at the center by a wooden pillar: a real tholos such as is already seen in the Villanovian age at Populonia and as those characterizing the funerary architecture of northern Etruria near the sea during the 7th century bc. By the end of the 7th century bc the success of this kind of tomb is con-

Fig. 17: Populonia, Tomb of the Chariots, internal views of the tomb

Fig. 13: Populonia, Tomb of the Chariots, external views of the tumulus Fig. 14: Populonia, Tomb of the Chariots, external views of the tumulus Fig. 15: Populonia, Tomb of the Chariots, gutter Fig. 16: Populonia, Tomb of Pissidi Cilindriche

Earthen Domes and Habitats Fig. 18: Tomb of Casale Marittimo, internal layout and view of the tomb Fig. 19: Quinto Fiorentino, Tomb of Mula, plan (from Tampone 2000) Fig. 20: Quinto Fiorentino, Tomb of Mula, view of the chamber

solidated in northern Etruria: the chamber tomb also conquered areas such as Chiusi and especially internal Etruria, previously reluctant towards these architectural forms. Rectangular chambers roofed with pseudo-vaults were rising with giant tumuli in Cortona, Castellina in Chianti and Comeana. In the same way, in the middle Valdarno and in the area of Volterra the circular tholos with a corbelled dome such as that of Casale Marittimo (Fig. 18) or those of the more magnificent Mula (Figs. 19-20) and Montagnola near Florence (Fig. 21) or of Montefortino, (Fig. 22) became the fashionable architectural type: testament to the tangible riches of the heads of the Etruscan communities of Oltrarno, who controlled the roads that converged there from Vetulonia and the Chiana Valley towards Bologna. From an architectural point of view, the Tomb of Mula appears to be the earliest of the profile which starts directly from the floor and spreads to a height of approximately the radius of the base, and also for the absence of a central pillar and vestibulo, these characteristics deriving from the Villanovian experience as in the tholos of Poggio Granate in Populonia, already cit-

Earthen Domes and Habitats

ed. On a circular plan, it is built with limestone slabs (alberese) in horizontal layers, with lintels of vertically oriented slabs. In other tombs we may observe that a height reaching almost the value of the diameter is associated to a central pillar. If the reason for the pillar comes from the experience of Vetulonia, the cruciform plan of the vestibulo of the Tomb of Montagnola recalls the tombs of internal Etruria. It is obvious that the connections between Etruria and the eastern Mediterranean do not confin themselves merely to funerary architecture, given the similarity found by scholars between Etruria and Asian Ionia for domestic architecture, from architectural coroplastica3 to funerary symbols and burial statues of lions, to mention just some examples, demonstrating the complexity of these contacts which are positively and constantly expanding our knowledge. Imitators The upheaval of the 6th century bc in Etruscan society, determined by the rise of oligarchies to rule the Etruscan cities instead of the â&#x20AC;&#x2DC;princesâ&#x20AC;&#x2122; of previous generations, brings new funeral rituals and new funerary architectures which are articulated with different organizations and forms according the different areas: from the tombs like houses in Tuscania, or as cubes in Norchia and San Giovenale, to the more rational and less cumbersome, such as the aedicula4 tombs of Populonia Processing technique of pottery in the archaeological field. Khora from the greek, meaning earth, and plastica, meaning shape. An aedicula (plural aediculae) is a small shrine. The word aedicula is the diminutive of the Latin aedis

Fig. 21: Fifth Fiorentino, Tomb of Montagnola, plan (from Tampone 2000)

In other areas of northern Etruria near the sea as in Roselle (Fig. 23) and Vetulonia (Fig. 24) we may see small rectangular chamber tombs with a short dromos, built inside a mound and covered with diagonally jutting out slabs, without pendentives in the corners, and a depositional bench formed by vertically laid slabs. This was a legacy of the great tholos architecture, which had by then given way to new architectural forms. Conclusions The similarities found between sepulchral monuments located in different areas of the Mediterranean offer us the opportunity to recognize those individual influences on funerary architecture imported by workers driven west under Assyrian pressure at the end of the 8th century BC (North-Syrians, Anatolians, Cypriots), and later Ionian people in Asia emigrating west during the 6th century bc away from Persian invasions. or aedes, a temple or house; thus, an aedicula is literally a small house or temple. Fig. 22: Comeana, Tumulus of Montefortino

Earthen Domes and Habitats

The low number of mounds studied in those areas limits the precise reconstruction of the flow of contacts, especially for the 7th century bc, although the scarce evidence indicates cultural and technical routes already travelled. An increased concentration of investigations in those places, therefore, could fill the gaps in our knowledge of the 7th century bc, since we can now benefit from evidence mainly prior to this period with the series of Phrygian mounds and later with the known examples in Asian Ionia (Sardis). Fig. 23: Roselle, Campo della Fonte, tomb chamber. Fig. 24: Necropoli of Val Berretta, (Castiglione della Pescaia) chamber tombs Fig. 25: Populonia, Tomb of the Colatoi, internal view

List of References Barbi, L. 2000, ‘Analisi delle caratteristiche tecnico-costruttive della Tomba dei Carri’, Zifferero A. (ed.), L’architettura Funeraria a Populonia tra IX e VI sec.a.C., Atti del Convegno di Populonia, 30-31 ottobre 1997, Firenze, pp. 61 ss. Bartoloni, G. 1987, Le urne a capanna rinvenute in Italia, Roma Bartoloni, G. 2000, ‘La prima età del ferro’, Zifferero A. (ed.), L’architettura Funeraria a Populonia tra IX e VI sec.a.C., Atti del Convegno di Populonia, 30-31 ottobre 1997, Firenze, pp. 19 ss. Bartoloni, G. & Bocci Pacini, P. 2002, ‘Roselle una rilettura dei dati di scavo nell’abitato arcaico’, Manganelli M. & Pacchiani E. (eds), Città e territorio in Etruria. Per una definizione di città nell’Etruria Settentrionale, Giornate di studio, Colle Val d’Elsa, 12-13 Marzo 1999, Colle Val d’Elsa, pp. 187 ss. Bruni, S. 2000, ‘L’architettura tombale dell’area costiera dell’estrema Etruria settentrionale. Appunti per l’orientalizzante antico e medio’, Zifferero A. (ed.), L’architettura Funeraria a Populonia tra IX e VI sec.a.C., Atti del Convegno di Populonia, 30-31 ottobre 1997, Firenze, pp. 151 ss. Colonna, G. 1986, ‘Urbanistica e architettura’ in Rasenna, storia e civiltà degli Etruschi, Milano, pp. 371 ss. Colonna, G. 2000, ‘Populonia e l’architettura funeraria etrusca’, Zifferero A. (ed.), L’architettura funeraria a Populonia tra IX e VI sec.a.C., Atti del Convegno di Populonia, 30-31 ottobre 1997, Firenze, pp. 253 ss. Crome, J.F. 1938, ‘Löwenbilder des siebenten Jahrhunde’, Mnemosynon Th. Wiegand, München, pp. 50 ss. Cygielman, M. 2002, ‘Per una definizione di città nell’Etruria settentrionale: il caso di Vetulonia’, Manganelli M. & Pacchiani E. (eds), Città e territorio in Etruria. Per una definizione di città nell’Etruria Settentrionale, Giornate di studio, Colle Val d’Elsa, 12-13 Marzo 1999, Colle Val d’Elsa, pp. 166 ss.. Cygielman, M., Baldin, G., Ragazzini, S. & Tuci, D. 2007, ‘Roselle (GR).Collina sud-Campo della Fonte marzo-maggio 2006’, Notiziario della Soprintendenza per i Beni Archeologici della Toscana, Scavi e ricerche sul territorio, n° 2, Firenze, pp. 315 ss. D’Agostino, B. 1991, ‘Dal palazzo alla tomba. Percorsi della “imagerie” etrusca arcaica’, Archeologia Classica, n° 43, pp. 223 ss. Karageorghis, V. 1967, Excavations in the necropolis of Salamis, I, Nicosia. Lo Schiavo, F. 2000, ‘L’ambiente nuragico’, Zifferero A. (ed.), L’architettura Funeraria a Populonia tra IX e VI sec.a.C., Atti del Convegno di Populonia, 30-31 ottobre 1997, Firenze, pp. 101 ss. Naso, A. 1996, ‘Osservazioni sull’origine dei tumuli monumentali nell’Italia centrale’, Opuscola Romana, no. XX, pp. 69 ss. Paolucci, G. 1998, ‘La diffusione dei tumuli nell’area chiusina e l’errata provenienza della seconda pisside della Pania’, Gastaldi, P. (ed.), Studi su Chiusi arcaica in Annali di Archeologia e Storia Antica, n° 5-1998, pp. 11 ss. Prayon, F. 1975, Frühertruskische Grab und Hausarchitektur, Heidelberg Prayon, F. 1989, ‘L’architettura funeraria etrusca. La situazione attuale delle ricerche e problemi aperti’, Atti del Secondo Congresso Internazionale Etrusco, Firenze 1985, Roma, pp. 441 ss. Prayon, F. 1995, ‘Ostmediterranee Einflüsse auf der Beginn der Monumentalarchitektur in Etrurien?’, Jahrbuch RGZM, n° 37, pp. 501 ss. Rathje, A. 1991, The adoption of of the homeric banquet in Central Italy in the Orientalizing period, in Sympotica. A symposium on the symposion, Oxford, pp. 279 ss.. Tampone, G. 2000, ‘Le tombe a tumulo etrusche dell’Arno e di Populonia. Confronti’, Zifferero A. (ed.), L’architettura Funeraria a Populonia tra IX e VI sec.a.C., Atti del Convegno di Populonia, 30-31 ottobre 1997, Firenze, pp. 173 ss. Waelkens, M. 1986, Die kleinasiatischen Türsteine, Mainz am Rhein. Young, R.S. 1981, Three great early tumuli. The Gordion excavations final reports I, University Museum Monograph, 43, Pennsylvania Zifferero, A. 2006, ‘Circoli di pietre, tumuli e culto funerario. La formazione dello spazio consacrato in Etruria settentrionale tra età del Ferro e alto arcaismo’, MEFRA, n° 118-1, pp. 177 ss.

Earthen Domes and Habitats

VERNACULAR CORBELLED DOME IN MEDITERRANEAN

Earthen Domes and Habitats

Stone and clay are natural materials with very different characteristics that enable man to build objects. While stone is difficult to obtain and not much easier to work, clay is a material which, prior to building, must be processed and shaped. Stone and earth: needs, possibilities and constructions There are a number of types of stone: they are distinguished by hardness, colour, structure, by possibilities of working and by durability. Clay is a material that is mixed with sand and water in order to give it the appropriate necessary properties. It is known by various expressions, which relate to different types of material: clay, mud, earth. When someone works in the fields from the crack of dawn, he also needs food and drink. This soon becomes tasteless in the burning sun, sometimes even unusable and dangerous. The most simple object in stone is a wall. A wall offers shade, but when the sun is in its zenith the shade disappears. So the food must be hidden in a niche. This is only possible by setting apart the two stones in the lower string and covering with the upper. The food is then in the shade all day long. The same applies to human shelter: a small hollow is enough for a single man, more people need more space. This must be composed. Stone, hands and intelligence are available (Fig. 1). Principles of construction of corbelling in practice The crucial difference between stone and clay is hardness: stone is hard, clay brittle. There is also a difference in maintenance: stone needs practically none, but clay without running maintenance already disintegrates after only two cycles of change in moisture or temperature. While stone can be used in a single piece (exceptionally, and with a limited

University of Ljubljana, Slovenia

Fig. 1: Comparison of the size of shelters: for eating, there is a great difference in the dimensions of the ground plan between that for a single man right up to a group of herdsmen.

span), even for a span under strain, for example as a bridge, this cannot be done with clay. Because of its brittleness, clay has the possibility of being used for constructing simple compositions with a great deal of static stability, but they depend on maintenance during the course of operation. Corbelling is gradual overhanging that is repeated from layer to layer, rising all the way to the capstone. Experience suggests that the ideal height of a construction is √3/2 of the diameter of the base plus the thickness of the wall. The composition of a shelter, right up to the largest, with a diameter of more than nine meters, has three elements: – corbelling as the supporting construction; – an external frame, which leads off water, and weighting elements of the corbelling as a counterweight; – a filler in between which fills and, with volume, gives weight to the composition itself (Fig. 2). Objects thus occur in which the corbelling and frame are almost combined (trullo) and also those in which they are completely apart (el bombo). The external shapes of objects are of course completely different. Clay is more usable in mass when the wall is composed directly of a single piece. There are a number of techniques and, of course, there is also the possibility of a construction made of bricks. This is ‘adobe’ (earthen brick), consisting of kneaded, straw reinforced and shaped, sun-dried bricks. Such constructions are, technically, statically less demanding, and even corbelling is not ruled out.

Earthen Domes and Habitats

Corbelling of the Mediterranean

Borut Juvanec

Earthen Domes and Habitats

cross section

groundplan

covering and counterweight

Fig. 2: Corbelling in practice: the supporting element in cross-section is overhanging. In the ground plan there is a circle (which thus avoids problematic corners), and a counterweight – as a frame which also gives form/ shape – serving to lead off water.

The invention of the arch enabled the development of plane compositions in space. A vault with all its derivatives is thus obtained, which the Gothic developed to the full. The arch was first used by the Etruscans, but the Romans were smart enough at the time of the destruction of the Etruscan nation to take on the useful elements of their culture. Further technological and technical development took place in parallel: concrete as artificial stone has the characteristics developed from compositions of stone and clay. It is a matter of the deconstruction and technological processing of stone and then building on the principles of a clay wall: with reinforcement. This combination brought contemporary architecture unheard of possibilities.

The beginnings of architecture Architecture begins with a construction that is functional, that gives the possibility of shaping and using space. This, immediately after a menhir, is a dolmen, as a composition of two menhirs covered by a lintel. In the technical sense, this is the simplest construction of a space, but difficult to erect given the size of the lintel, finding it and its considerable weight. A string of dolmens form a longitudinal space called a corridor (Zupancˇicˇ 2003). The next phase is a room: at first small and then increasingly larger. At the beginning it is covered with a stone plate, but this is clumsy and difficult to achieve. A flat stone, weighing several tens of tons, is difficult to place on the supporting construction. So brain replaces brawn: the space has to be composed of small stones. The principle is overhanging, and the result a false cupola, false dome. The elements of construction are horizontal layers, and the ground plan is as circular a construction as possible (Juvanec 2005). In corbelling, the stone is not dressed or only partially dressed. An arch consists of dressed stones that carry the arch in which the stones are oriented towards the centre. The stones must be dressed, since they have to be narrower at the bottom than at the top. In the centre is the central and largest load: the keystone (Juvanec 2005). When stones are dressed in three directions, it is possible to compose a space: a cupola. A dome is the first modern architecture. Variety of objects Objects essentially differ between stone and clay in terms of purpose. While clay is unknown for marking, which is the first, simplest and oldest erection of stone, items for kings, the gods and the dead are made of stone and only rarely clay, since the objects of this devotion in architecture do not perform maintenance. In particular, classical and modern architecture uses stone and fired clay; there is no adobe system here. In relation to the use of clay, mention must also be made of its conductivity of heat: it is an excellent insulator and can be used for retaining heat. Wattle constructions are in general problematic: whether a wooden composition of a wall, which is bound and protected on the outside by clay, or a solid clay construction that is only strengthened internally with wood. We can thus consider the variety of objects separately in stone and in clay (Fig.3).

Earthen Domes and Habitats

Fig. 3: Corbelling has a constant form of construction in the interior: on the outside the architectural composition can be of any kind. It follows possibilities, needs, available materials and, above all, the creativity of the builder. Two elements are important and must be fulfilled: the composite parts of the corbelling must be weighted on the outside (counter-weighting) and atmospheric water must be led off. There can be filling between layers but this is not essential.

Fig. 4: A bridge links two banks: the greater the span the greater is the amount of water that it allows through. An aqueduct (a ‘bridge’ which leads water from its source to a cistern) in Matmata, Tunisia, is a classic example of corbelling in the simplest of practices.

Corbelling allows the bridging of a span by means of alternation. This is in two dimensions: it creates a false cupola in the space. The object is called a shelter, with a host of local names which more or less originally describe the construction or purpose: vrtujak on Korcˇula refers to the spiral construction towards the top, pont de bestiar in Menorca simply means a stable for livestock. Stone shelters can be found from Iceland to the Yemen, from the Isle of Lanzarote in the Canary Islands to Palestine. These objects have their own documentation, and according to the literature they exist in Georgia, Tibet, South Africa, South and Central America and probably many other places (Juvanec 2005). Bridges and aqueducts are vertical constructions that carry communication (a path for man, a ditch for water) across a hollow. Aqueducts can be found in Tunisia that take water from a collection point to a cistern (Matmata), in Southern Italy there are bridges made with corbelling, in Spain with a dry arch, in Devon (UK) there are bridges from a single stone (Fig. 4). Complexes of walls which have a special purpose as an object are the Maltese dura, which conceal hunters from game, or the French coup vent, which protects against wind. There are even ‘walls against plague’ in France.

A soot house in Ireland, an ash house in Devon (chickens also lived in the house and enriched it with their droppings) are purpose-built objects which are barely recognised and hard to find today. The construction of a sweat house in Ireland is similar. As a kind of sauna it purifies a person’s body and spirit when he is built into the hot object. Corbelling as the construction of superstructure is an important element of wells, which in Croatia collect water through a permeable roof, in Spain and in Montenegro fill with, retain or purify water or fertile soil (Tivat). Sacred wells in Sardinia are a particular challenge to researchers. In terms of design they copy the Egyptians (some are even from the same period) but outdo them in the introduction of a new construction principle: corbelling. The well of Sant’Anastasia is particularly important in this respect, which, on the saint’s name day, projects the sun’s rays from the opening of the well so that they appear to be coming from Earth. This is made possible by the corbelling of the well and the stepped entrance, using a physical phenomenon where the angle of incidence is the same as the reflection. Even the name stresses this, since the name Anastasia derives from the word anastaza which means rising, resurrection (Zupancˇicˇ 2003). It was a matter of politics: miracles attract people, the greater the

Earthen Domes and Habitats

miracle the more people, more people means more money, more money greater power, and power represents authority. There are far fewer remains in clay; if not maintained, they completely disappear after only a few decades. These examples are therefore mainly of more recent date, although some older ones can be found. Clay architecture can be compacted, massive, rammed or kneaded, and can also be composed from previously prepared sun-dried bricks. First, for durability it must be reinforced, the most prized are with juniper branches that harden over time and almost fossilise. Kasbahs in Morocco and the architecture of the Yemen also include high buildings with inwardly inclined outer walls, for static reasons as well as for â&#x20AC;&#x2DC;self-maintenanceâ&#x20AC;&#x2122;, when rainwater that collects on the terraces flows down the walls and daubs possible minor cracks. The adobe system has bricks that are reinforced with short pieces of straw, which are then built mainly into vertical walls using a technique of alternation. Residential architecture, as the most important, is normally protected on the outside with a coating that is today called plaster. It is possible to bridge a space using clay bricks with small alternations, essentially smaller than with stone, since the fragility of air-dried bricks is great and does not bear stretch tension. So constructions are higher than those from stone, and they have openings or wooden beams on the outside, which enable them to be reached for constant repairs and maintenance. The shape of clay dwellings also appears on the outside of the construction, in contrast to stone, which has a double wall (constructional and coating). The shape of a false cupola is a spindle, an object in clay is essentially higher than stone, so these compositions are also called beehive houses, after beehives of straw or husking. The best known are in the Lebanon, along the Turkish border, on both sides (Harran), but they also exist in Syria, and also in Spain, near Palencia, North of Madrid. The architecture of the Mediterranean is stone; clay is almost never found, except in details, since there is clearly too much humidity and rainfall (Fig. 5). Clay appears in vernacular architecture as a binding material, as insulation, for sealing, and as a crown material on walls, protecting them from external influences, and sometimes also as a colour wash. A technological process, firing, strengthens a clay brick and it becomes

Fig. 5: Corbelling in stone and in clay: because of the essentially lower hardness of adobe bricks, the height required for overhanging a span is essentially greater than in the case of a stone construction.

Fig. 6: Internal height determined by means of the height of an equilateral triangle.

Fig. 7: Theory of an equilateral triangle and calculation of height.

Fig. 8: Equilateral triangle in practice: the baseline looks difficult or even impossible to measure, but it is not: it is determined with a stick leading from the external edge by the entrance to the farthest point in the interior of the object.

Identified characteristics Stone shelters are in principle corbelled and this construction defines the interior space, which is the same in all compositions. In contrast, the external form is a matter for the author, heritage, local characteristics and natural possibilities, above all material and location. Corbelling is the principle of overlaying, overhanging. The rule that the alternation may not extend over the centre of gravity is crucial. Not just the element immediately below, but all lower elements. After analysing hundreds, if not thousands, of cross-sections, we have found that an equilateral triangle plays an important role in the construction (Fig. 6). In 2002, after detailed examination, we determined the height of 50 buildings from throughout the Mediterranean with the aid of this triangle. It appears that the ideal height of a stone shelter is half the square root of three (√3 divided by 2), if the baseline is the diameter plus the thickness of the wall. This is therefore proved. If the construction is lower, it falls down. If it is higher, essentially more work is required for it, which is unnecessary. Vernacular architecture never took one step more than was necessary. The essence of the use of half the square root of three is its simplicity: it can be made from three sticks of equal length. Three sticks are the simplest and most available tools for shepherds on the pasture, and the only figure which can be made from them is a triangle. It is true that builders of the past knew nothing about square roots, but they knew how to draw a construction if they had measured the depth of the ground plan from the beginning of the entrance: 2r+w (where r is the radius and w the thickness of the walls). As calculated in the case of 50 similar objects, the height is within a framework of plus/minus less than two centimetres. The exactness of the stone constructions using an equilateral triangle and with the aid of √3/2 is thus within an error of less than 1.5 percent. The stone constructions were actually built by genuine masters (Figs. 7-8).

Origin and examples from the history of corbelling While there are few historical remains in clay, primarily dried clay, since only traces of lost constructions can be found today, there are many stone compositions, also in vernacular architecture. The oldest known objects in corbelling are tombs in northern Yemen, on the border with Saudi Arabia, Ramlat as-Sabatyn. In areas which are today difficult to access, there are thousands of circular stone tombs dating from the sixth millennium BC (Steimer 1999 and 2001). An imitation of corbelling engraved in stone in Malta has been dated to between the third and fourth millennia BC: Hypogeum Hal Saflieni. The underground tomb or sacral space is part of a larger complex. It is a presentation of a circular ground plan and stepped construction of the roof, which indicates the existence of such constructions even before this. Compositions of actual corbelling are only about a thousand years more recent: Hagar Qim, Mnajdra on Malta and Ggantija on Gozo. Huge semidressed and levelled stones stand vertically as high as a man’s reach, and the construction then starts gradually to overhang inwards. If the compositions were finished – unfortunately there is no evidence of this (De Luca 1984) – they must have created a huge space, forming a cluster of shrines. The complex at Memphis in Egypt dates from the start of the second millennium. The best known are two pyramids, Bent and Red. The Red Pyramid contains a string of longitudinal rectangular chambers with a

Fig. 9: The most recent stone shelter – ‘vrtujak’ on the island of Korcˇula (Croatia) was erected in 2008.

Earthen Domes and Habitats

a permanent construction material in building. However, even fired clay does not bear stretch tension and with bricks, too, we can only build constructions with downward forces, an arch in two and a vault in three dimensions, in space.

Earthen Domes and Habitats

Fig. 10: While the interior supporting part is always the same, the outside can be very different: a. External frame follows the internal shape (examples: crot/scele, Switzerland, caprile, Elba, Italy, barraca, Catalonia, Spain, cabane, Provence, France) b. When there is no rim added later around the basic body, the visible part of the shelter is step-like (pont de bestiar, Menorca, Spain, trim, Hvar, Croatia) c. The external wall can be vertical or slightly inclined inwards – between the corbelling and the wall, metalling is used as a filler. The central opening is normally covered with a capstone, the ‘roof’ (metalling) is inclined outwards in order to ensure the flow off of water, while the internal ground plan is normally circular. The exterior of the shelter can be circular or square (examples: girna, Malta, trim, Hvar, Croatia, pont, Menorca, Spain). d. El bombo in La Mancha, Spain is a special and unique example, in which there is a multi-cellular complex in corbelling, surrounded by a relatively low wall, and the construction is filled with metalling. Around Tomelloso, as the stones slide, a completely natural shape of shelter is formed.

corbelled roof construction. The horizontal layers are at least a metre and a half to two metres thick. This is typical corbelling in cross section, in dressed stone. The same applies to the Lion Gate: the corbelled stones form an irregular arch, a triangle over the lintel. They clearly did not have faith in this construction, since a poorly decorated slab was placed in the centre to ‘assist’ the massive construction. This group also includes small, relatively poorly researched sacral objects with a corbelling construction and with the same or similar elements of construction, design, detail and dimensions: the Tomb of Comeana from the 7th century BC, the Tomb of Cortona from the 2nd century BC (Zaccaria 1991) and a number of unproven age: • Šuplja gromila by Šibenik, Glattjochkapelle in Austrian Styria and Gallarus Oratory on the Dingle peninsula, Ireland, the Verhnij Kokadoi tomb or shrine from the 13th or 14th century. • Šuplja gromila and Verhnij Kokadoi are almost identical compositions in terms of dimensions, shape, construction, in terms of elements (two niches) and the position of the niches. Four of the six monuments are located on the same longitude and run from east to west within achievable distance of influence. Stone shelters of the modern era are mainly two hundred or at most

three hundred years old. Their age can only be determined from tradition, since even C14 radiocarbon dating is fairly unreliable in this case. Enrico Degano, who found a plaque in a shelter with the date 1559, marked this with a question mark (Zaccaria 1991). Michelangelo Dragone shows the origin of a plaque from a neighbouring object in a vineyard (Marziola, Puglia I). Degano located a subsequent object in the vicinity (Il Bello) with the date 1672. Berislav Horvaticˇ reports an entry in the Katastik about comardaz, about two komardas (sing. komarda) on the island of Krk (Croatia) in 1577 (Horvaticˇ 2000), which indicates that these constructions were already there prior to this date. Christian Lassure found the oldest object in the Department of the Lot (Pierre Dallon: Cieurac) from 1653 (Lassure 1985) but there also exists an object with the date 1620. This appears to be the oldest such construction with a reliable dating. Absolutely the most recent vrtujak today (in 2009) was erected in the winter of 2008 on Korcˇula. It is a completely accurate construction, with an internal height of 3,05 meters (Fig. 9). Shelters as an object Shelters as an object began with layering: covering is the only way of ensuring some solidity without binding. Each vertical junction must be covered: in order to prevent the entry of water and to ensure by means of weight that the lower elements will not slide apart. When the lower two stones are spaced, the same effect is obtained, and the opening can be used for storage. To begin with this was a bottle with something to drink and some bread for lunch, later shade for a person; and protection from the heat and cold is already a larger object: for a single person, or two or more (Juvanec 2005). The theoretical start is within a wall, and many shelters are precisely that;

Earthen Domes and Habitats

clochane (IRL)

twlc mochyn Wales ash house (UK)

weinbergshaeuschen (D)

crot (CH) hiska (SLO) kazun (HR)

cabane (F)

komarda bunja trim vrtujak

caprile (I)

chozo (E)

pagliaddu (F) trullo (I)

barraca (E) pont (E)

pinnetta (I)

bombo(E)

gima (M)

mitata (GR) mantarah (PAL)

then of course it stood in front of the wall, in it, behind it or outside the wall, completely independently. Internal elements such as niches, windows, door openings, chimneys and ventilation are matters of need (Fig.10). External elements that appear are merely an expression of the builder and the desire of the owner for emphasis. The latter is connected with old religious beliefs, which are sometimes contradictory: for example, a pinnacle at the top of the roof is supposed to drive off evil spirits, as well as lightning. Others say that it attracts them so that men do not enter. In Spain and in the Yemen, the window frame is painted with lime: against

nawamis (Synai) howd (Yemen)

Fig. 11: Stone shelters can be found from Iceland to the Yemen, from Lanzarote to Palestine (Documentation: Borut Juvanec, University of Ljubljana, Slovenia).

evil spirits. In reality, insects like to breed in the dry-stone walling and lime inhibits their access into the interior of the object. Stone shelters generally stand on their own, each in its own area of pasture; only rarely are they set in a group (such as for example around Ĺ ibenik). Small ĹĄiĹĄka, as they are also called in Slovenia, can also be the fruit of an enthusiastic herdsman, who builds as many as five on his own pasture. In terms of type, stone shelters of the Mediterranean are as follows (Fig. 11).

Earthen Domes and Habitats

Barraca, Catalonia, Spain barraca, El pont de Villomara, Catalonia

Bunja, trim, Dalmatia, Island of Hvar, Croatia trim, Ager on the Island of Hvar

Mitata, island of Crete, Greece mitata on the Nida Plateau, Crete

Pagliaddiu, barracun, Corsica, France paghliaddiu near Santu Pietru, Corse

Pinnetas, island of Sardinia, Italy pineta on the Romana plateau, Sardinia

Pont de bestiar, Menorca, Spain pont de bestiar near Talati de Dalt, Menorca

Tazota, Morocco tazota or nwalla, not far from El Jadida

Trullo, Puglia, Italy trullo system, masseria Maccherone near Alberobello

Vrtujak, toreta, Island of Korcula, Croatia vrtujak on the hills over Vela Luka on the Island of Korcula

El bombo, La Mancha, Spain el bombo near Tomelloso in La Mancha

Cabane, France cabane in Provence

Caprile, Island of Elba, Italy caprile, Macinelle on the Island of Elba

Chozo, Extremadura, Spain chozo in Extremadura

Girna, Malta girna near Red Tower

Hiska, siska, Slovenia hiska on Slavnik Karst/Carso

Kazun, komarda, Istria, Island of Krk, Croatia kazun in Istria

Bunja, trim, Dalmatia, Island of Hvar, Croatia A bunja is a shelter in Dalmatia: at one time they could be found all the way from Zadar to Makarska. There are most in the vicinity of Šibenik and on some islands (Žirje). Some there are also found with a multi-cellular ground plan. A trim is an object on Hvar, where they stand both in the wine-growing plains behind Stari Grad and on the ridge of the island, as well as on the northern slope. They are relatively large objects with ring-shaped bodies, which testify to their ‘perfection’. The result is a stepped roof with stairs for access, repair and maintenance work. An important part of a trim is the collection of water in a cistern, which in many places is accessible from the inside, and viticulturists use them for watering and for water storage in numerous basins. They are still in use on Hvar. El bombo, La Mancha, Spain See the specific contribution on Spain and Portugal. Cabane, France See the specific contribution on France. Caprile, Island of Elba, Italy A caprile (plural: caprili) is a small object, almost semicircular on the outside and intended for shepherds, which has an enclosure behind for protecting the herd of sheep during the night. These enclosures also have a semicircular ground plan. Elba is a small island, and goats seek their own food. In places there are a number of caprili together and they stand with the entrance oriented towards a common courtyard, where the social life of the herdsmen takes place. Chozo, Extremadura, Spain See the specific contribution on Spain and Portugal. Girna, Malta A girna in Malta has its nearest example in shrines constructed in corbelling

thousands of years earlier. This kind of solution is therefore not coincidental (Fig. 13). A girna (plural: giren) can be circular or square, stepped or in the form of a truncated cone. Some giren have steps, or even a ramp, to the roof, where fruit is dried. The roofs are not emphasised and do not generally have a rim; occasionally they are fitted with a pinnacle, normally only with a flat capstone. Some are meant for animals, including pigs, others are for vineyard tools. Those which are for herdsmen have an inbuilt noose for fastening and an opening, plus a window for looking out. Stepped ones in particular are extremely harmonious, when they display their growth from a conical object with a ring-shaped circumference into stepped giren and thus show the exploitation of space, the functional execution and adaptation to the needs of the time.

Hiška, šiška, Slovenia A hiška, in places also šiška or kutja is a hut on the Karst. This is a small object, barely higher than a person, and may also only reach to the chest; it is built into a stone wall, stands in front of it or behind it, or can be in a corner or stand independently. The material is undressed grey stone of various shapes, larger stones are used only for the capstone and the entrance part. This is sometimes a conical opening to enable the herdsman sitting on the stone bench inside to watch the herd. The roof is conical, sometimes having a pinnacle at the peak and never has a rim around it. The ground plan is generally square or close to a square, it is not circular on the Karst. Kažun, komarda, Istria, Island of Krk, Croatia A kažun is a shelter on the Istrian peninsular in the northern Adriatic. It has a square ground plan (or close to a square), or a circular one. The external wall is vertical to the roof, the roof has a rim and rises to the central part, where there is a pinnacle. There are sometimes four additional pinnacles, at each corner of the roof. The interior is angular or circular, which is also followed by the roof: the corbelling sometimes approaches the capstone in four levels, which is rather unusual. A kažun normally has a bench inside and a space for a hearth in the middle. There is sometimes an opening at the capstone for smoke to escape. Niches

Earthen Domes and Habitats

Barraca, Catalonia, Spain See the specific contribution on Spain and Portugal.

Earthen Domes and Habitats

provide space for the herdsmans necessities. The positioning of a kaĹžun in space is extremely aesthetic, especially among the greenery of Istria, which we do not find elsewhere in the Mediterranean. A komarda is a smaller object on the island of Krk, which is normally in the framework of a wall and serves only for emergency protection. The entrance is often concealed from view to prevent access by animals. A komarda on Krk can stand high in the hills of the central part of the island.

Mantarah, Palestine Mantarah means â&#x20AC;&#x2DC;watchtowerâ&#x20AC;&#x2122;: enabled by the height and truncated cone shape. The massive construction has internal corbelling set eccentrically, so that in the dressed part of the wall there can be a spiral staircase to the roof. Fruit is dried there, and there is a view to the herd, the olive grove or even an approaching enemy. A mantarah is built from relatively large stones, which are finely dressed and well set into the inwards inclining wall of the object. They can be held by a wall, but a mantarah is never part of a wall: they are different also in terms of size. Several objects often stand in a certain space, relatively close together and in a prominent position, which also serves to give the object greater importance visually. Mitata, island of Crete, Greece See the specific contribution on Greece. Pagliaddiu, barracun, Corsica, France Pagliaddiu, (French pailleur) which is also written as pagliaddju or paghliadiu, is a rectangular object found in the northern part of the island of Corsica. On the outside it has a slightly inclined wall up to the edge of the roof, which is emphasised, and the roof is made of turf sods gently sloping to the ridge. The corners are from larger construction stones, which overhang outwards to enable someone to climb onto the roof for maintenance work. In the interior, in both axes there is a typical cross section of corbelling with a number of successive terminal stones along the length. There is a hearth in the end wall, the smoke from which escapes through a chimney that is almost unnoticeable from the outside. The entrance has a short projecting roof, sometimes a ventilation hole above the lintel, and beside the door are additional storage shelves. A pagliaddiu always stands on a hill, set back

Fig. 12: A tazota near El Jadida, Morocco

Earthen Domes and Habitats

Fig. 13: A girna in Malta

Earthen Domes and Habitats

Pinneta, Sardinia, Italy See the specific contribution on Sardinia. Pont de bestiar, Menorca, Spain See the specific contribution on Spain and Portugal. Tazota, Morocco Tazota is the Tamazight (Berber) name. The tazota is found in part of Morocco near El Jadida, about one hundred and fifty kilometres from Casablanca or Marrakesh (Fig. 12). A tazota is an object in reddish stone, on two levels, with two openings: below and in the upper part. Stairs lead to the upper part, since straw is carried into it here from a cart and then, when required, it is taken through the lower doors. Above is screened with branches, so that children do not fall into the tazota, and below there are wooden doors, to restrict use. A tazota stands in the courtyard of a farm and is continually watched over. The construction is corbelled in the interior to the capstone, it has a circular ground plan, and on the outside is rectangular with rounded corners. The stone is dressed on the outside. Trullo, Puglia, Italy See the specific contribution on Puglia. Vrtujak, toreta, Island of Korcˇula, Croatia There are three kinds of shelter on the island of Korcˇula: in the west there is the vrtujak, in the central part around the village of Smokvica there is the toreta and in the eastern part there are the bunja and toreta. Vrtujaks are erected in vineyards where they serve as shelters and for storing tools. In two cases the vrtujak has a tower, from which the sea can be seen. The erection is various, as is the shape: the ground plan is predominately circular, the roof more or less stressed with a rim and with a capstone: picun in the centre. Roofs depend on the builder. Some are excellent and harmonious and

they enrich the cultural landscape. Unfortunately, nature around them has today changed: at one time a vrtujak stood in the open in a vineyard, today they are overgrown with dense brush and they can be difficult to locate. A toreta is a shelter in local material, a stronger and darker stone which is also less dressed. A toreta has an oblong ground plan and is essentially higher than a vrtujak, it can be more than three metres to the internal capstone. Outside it is stepped, there are walls around a toreta which define the space for man (benches, table, niches) and a separate space for animals.

Outside the Mediterranean Outside the Mediterranean, a range of objects in corbelling exist, which serve as shelters, for storage, drying, etc. Ash house, Devon, UK is a high construction in which ashes are stored. The hens also live in the ash house, their droppings enrich the ash, which is then used as fertiliser in the fields. Clochane, Ireland is a shelter in dark, semi-dressed hard stone, the external shape of which follows the interior construction and it actually looks like a ‘beehive hut’, as it is also called. There are most clochanes on the Dingle peninsular in southwest Ireland, but the best known are on the island of Skellig Michael, which was inhabited by monks. Crot/scele, Switzerland is an object for herdsmen if it is far from the farm, and if it is closer to home it is used for cooling milk, and a stream may sometimes be directed through to lower the temperature. Howd, Yemen (Haraz Mountains) is a composition for herdsmen, pressed onto the hillside due to an extreme lack of space. Nawamis, Sinai (Ein Khudra) is very probably rough architecture of a circular or oval ground plan with a gently sloping roof of rubble. There is little likelihood that this was a granary from the time when the Sahara was fruitful and green (fourth millennium BC) because of the extremely small entrance openings. Soot house and sweat house, Ireland, are stone objects, the former for storing soot, which was then used for fertiliser, and the latter served as a kind of sauna. Twlc mochin crwn, Wales, UK is a circular object which served as a pigsty (as the name translates: ‘circular pigsty’).

Earthen Domes and Habitats

from torrent streams. They are still used today as stables for donkeys. A barracun or barracone is a circular object of simpler construction in the south of the island, but sadly there are only a few still left.

Earthen Domes and Habitats

Informing, documenting and analysing The problem of stone shelters is their existence today, when there are hardly any possibilities for their use. It is true that there are exceptions, such as the pont de bestiar in Menorca for horses, mitata on Crete for herds of goats, trullo in Puglia for human dwellings, but these are exceptions. The problem is the abandonment of activities, which means the abandonment of the objects. Because they are abandoned and falling apart, they are unimportant to the average person. The elements of the solution are informing, documenting and analysing. All this is professional and demanding work connected primarily with education and culture. People must be told what they have, why this architecture is so important for their culture, and they must be helped in raising awareness as to the value of their culture. National institutions for protection of the cultural heritage are not helpful in the majority of cases: they do not have information, or records, or documentation. These have been taken over by â&#x20AC;&#x201C; generally non-governmental â&#x20AC;&#x201C; organisations such as CERAV in Paris, SPS Le Val, ARTE Caceres, Patronat de Sant Calderic Barcelona, DSWA Milnthorpe, Cumbria, UK, and many others (Fig. 14). Documentation is the next step: this is above all an expensive procedure, connected to seeking, measuring, drawing, processing, photographing, taking the GPS coordinates, and composing documentary material. Analysis is highly professional work, we process the collected and selected data by various criteria: by geographic area, by ethnic origin, by use, by material, by construction, by technology, by composition, by proportional principles, by details, by shape, etc. Aesthetics depend to the greatest extent on the proportions and on the use. Protecting objects that are as vulnerable as dry-stone constructions is a special problem. Protection is dual: physical and through legislation. Protection through legislation is possible with the help of doctrines that have been adopted at various congresses of professional and scientific organisations (UNESCO, ICOMOS, etc.). In practice, it is possible to protect national property, but small objects of vernacular architecture are predominantly in private hands. This makes it difficult to enforce restrictions on non-professional interventions, which are quicker, cheaper or more achievable for the owner, since any restriction, even a positive one, limits the individual. There are also special problems in this regarding financing. The use of ver-

Fig. 14: Documentation presents first the location, then a description with all available data (origin, builder, ownership, materials, time of creation and maintenance work, old photographs, etc.), then technical plans, sketches, pictures, photographs, analyses and comparisons with other objects.

nacular architecture today is problematic since it does not provide real use, or comfort or effect, and it is extremely expensive in comparison with contemporary technical materials and technologies. Vernacular architecture as a museum exhibit is a dead thing. In part it is possible to use it to demonstrate its living function, but this requires exceptional effort and above all enthusiasm, since this cannot be successful financially. Tourism is an important element in this, but precisely in this we must be particularly careful: mass tourism does more harm than good. So it is necessary to choose a technology which explains the essence to the tourist, but shows it without his/her effort, using high-tech technologies, which are also the most comfortable for such a visitor: video, pictures, exhibitions and in computer simulations. We can take only the real connoisseur to the original object: and this represents tourism of the highest form for the smallest circle, and also with the greatest financial effect. Vernacular architecture is not possible directly in contemporary, modern architecture: we can only use it advisedly, in some features, in idea, in composition, in mass, colour, in some materials. Tomorrow and in the future, there are tasks for professionals in all the aforementioned elements: in informing, recording, documenting, analysing, protection and in conservation. The most important element is education, since it is necessary to tell people how important the heritage is for their culture, that it needs to be recognised, understood, valued and accepted as an asset of the cultural space, nation, time. Pride in the heritage is linked to recognising and understanding it.

Conclusion Vernacular architecture has been helped to a large extent by nature: fertile soil must be cleared of stones. A construction is the result of need, since stones thrown in a heap gradually disappear. A construction is necessary: and corbelling is the simplest method. And if an object is going to be constructed, it should at least be functional. Corbelling has been known as a constructional principle in classical architecture for several thousand years: a little less than three thousand years ago it was supplemented by the arch, which defined a vault and subsequently a cupola. The first cupola, the Roman Pantheon, is also the first modern architecture of our time. However: this was made by masters, who were acquainted with the achievements of high culture and had learnt there. On the other hand, unschooled but not unlearned masters were building smaller constructions in the simple method of overhanging much, much later, right up to today. It is important that this is a new invention of architecture each time, since local masters did not have the opportunity to travel, and were not acquainted with, had not seen and did not understand already existing solutions. If according to the great theoreticians (such as Vitruvius) architecture is the complex of needs, possibilities and opportunities, with the result being function, construction and aesthetics, vernacular architecture is simply the realisation of these starting points. Vernacular architecture is theory in practice.

List of References Anati, E. 1985, I Sardi, Jaca Books, Milano. Contu, E. 1999, Pozzi sacri, ipotesi riconstruttive, SACER, Sassari. Degano, E. 1990, Mostra documentaria della Puglia, Schena Editore, Fasano. De Luca, D. 1984, ‘Mediterranean Arch, The vernacular Identity’, Atrium 4, Malta Egenter, N. 1992, Architectural Anthropology, Structura Mundi, Lausanne Fsadni, M. 1992, Girna, Dominican Publication, Rabat Horvaticˇ, B. 1999, Mrgari, rozice od gromace, Krcki kalendar, Rijeka Horvaticˇ, B. 2000, ‘Puntarske komarde iz 1577. godine’, SACE 19, Punat Juvanec, B. 1996, Istarski kazun, Prostor, Zagreb Juvanec, B. 2001, Two Thousand Years and More in Architecture, UNESCO ICOMOS, Paris Juvanec, B. 2001, Reinventer les abris en pierre, ICOMOS Congress, Quebec Juvanec, B. 2005, ‘Kamen na kamen/Stone upon Stone’, I2, Ljubljana Juvanec, B 2006, ‘Tan lejos y tan cerca, Piedra con raices’, ARTE, Caceres Juvanec, B. 2008, ‘Chozo de extremadura, Joya en piedra’, ARTE, Caceres Juvanec, B. 2009, ‘Architecture in Slovenia 1, Alpine Part’, I2, Ljubljana Lassure, C. 1985, ‘Elements pour servir a la datation’, CERAV n° 5, Paris Lassure, C. 2004, Cabanes en pierre seche, EDISUD, Aix en-Provence Lassure, C. 2008, La pierre seche. mode d’emploi, EYROLES, Paris Oliver, P. 1997, Encyclopedia of Vernacular Architecture, Cambridge University Press, Cambridge Steimer-Herbet, T. 2004, ‘Classification des sepultures dans le Levant et l’Arabie occidentale’, BAR, International series 1246, London Steimer-Herbet, T. 2003, ‘Dolmen-like Structures: Yemen’, Proceedings of the Seminar for Arabic Studies 33, Archaeopress, Oxford Steimer-Herbet, T. 2001, ‘Le bronze ancien du Ramlat as-Sabatayn (Yemen)’, Paleorient vol 27/1, CNRS Editions, Paris Steimer-Herbet, T. 1999, Monuments funeraires megalithiques au Proche-Orient, Megalithisme de l’Atlantique a l’Ethiopie, Editions Errance, Paris Vegas, F. & Mileto, C. 2001, Memoria construida, Universidad Politécnica, Valencia Vellinga, M., Oliver, P. & Bridge, A., 2007, Atlas of Vernacular Architecture of the World, Taylor and Francis, London and New York. Zaccaria, C. 1990, Architettura in pietra a secco, Schena Editore, Fasano Zaragoza, C. 2000, ‘Arquitectura rural primitiva en piedra seca’, Politecnica 10, Valencia Zupancˇicˇ, D. 2003, Sardinija, arhitektura kamna, Univerza v Ljubljani, Ljubljana

Earthen Domes and Habitats

Weinbergshaeuschen, Germany are watchtowers in vineyards; the best known are from the time of the Napoleonic wars, which protected the wooden poles of the trellises from soldiers, who wanted to burn them during the cold winters. Fiskbyrgi, Iceland are fish drying houses (Gufuskalar), and fjarborg is a shelter for sheep near Rettarnes farm (Hella); a characteristic is the completely undressed, unshaped volcanic rock. Stone shelter, Lanzarote, Spain is a shelter in vineyards on this Canary Island.

Earthen Domes and Habitats

Politechnic University of Valencia, Spain

Corbelled dome architecture in Spain and Portugal is the result both of agricultural activities and, above all, the transhumant economy. Geographical, economical, climatic and geological context At the same time, the agricultural vocation of some rural areas on the border between Portugal and Spain is one of the other factors that generate the use of corbelled domes for stores, wells, drying places, wine cellars or granaries. In some cases, the combination of a need to keep an eye on crops and monitor livestock, as in Castilla La Mancha, may tally with such watchtower constructions as vineyard observers or cattle watcher huts (Fig. 1). On the other hand, the transhumant economy in a large part of Iberian Peninsula consists of the shepherds’ custom of moving livestock (mainly goats and sheep) from one pasture to another in a seasonal cycle, from the northeast zone of the Peninsula (in spring-summer) to the southwest area (in autumn-winter). For shepherds, place is recognized in terms of time, seasons, arrival and departure, aside from a separable object called ‘space’. For this reason, one of the forbears of their shelters could be the wooden stick structure covered by vegetation. Initially this hut, called chozo de muda could be moved by shepherds from one place to another according to requirements during the transport of livestock from one pasture to another (Fig. 2). From this point of view, it is possible to understand the settlements of shepherds made using corbelled dome shelters along transhumant paths. The relationship between the peasants and the local available resources may be useful in identifying key principles for the understanding of vernacular buildings, human settlements and sustainability. Credits. For the information provided: Miguel Cañas, Mariana Correia, Juana Font Avellano, Victorino Palacio, José Manuel López Osorio, Ástur Paredes, Juan Salvador López, José Maria Sastre, Miguel Sobrino, Museo de la piedra en seco, Villafranca, Castellón, Spain. Drawings from Vegas & Mileto Arquitectos Collection . Photos by Fernando Vegas, Camilla Mileto, Valentina Cristini and José Ramón Ruiz Checa

Fig. 1: Corbelled dome shelters close to dividing walls of estates

Urban and architectural morphology and function The features of Iberian corbelled domes may be outlined according to: • the surroundings of the hut: some shelters may also appear grouped in series. These constructions always occur close; • to the natural environment, both on agricultural plains and terraces or hilly pastures, depending on the geographical features of the surroundings; • the disposition of the hut: agricultural and shepherds huts are mainly free standing. Nevertheless, in areas divided by dry-stone walls, agricultural huts are found upon the edges or angles of these walls to save effort and to avoid the building of more walls (Fig. 3); Typologies of corbelling dome constructions in Spain and Portugal

Provinces with presence of adobe corbelling domes Provinces with huge presence of stone corbelling domes Provinces with medium presence of stone corbelling domes Provinces with few presence of stone corbelling domes Oviedo Santiago de Compostela

Santander Bilbao

San Sebastian Pamplona Zaragoza

Valladolid

Porto

Barcelona Tarragona

Salamanca Coimbra

MADRID Toledo

LISBON Evora

Faro

Teruel Castellon de la Plana Valencia

Merida Alicante Sevilla Malaga

Granada Almeria

Earthen Domes and Habitats

Corbelled dome architecture in Spain and Portugal

Fernando Vegas Camilla Mileto Valentina Cristini

Earthen Domes and Habitats Shepherds/livestock shelter construction Store/stock Paesant shelter construction Hydraulic construction Archaeological site

• the layout of the hut: it is common to find several variants, but in general the layouts may be summarized in circular, rectangular, squared and celllike (Fig. 4); • the cross section of the hut: it is common to see many regional changes, but in general the sections can be rectangular, triangular or circular; • the vault of the hut: it is usual to see cylindrical, cone, half-spherical or combined solutions for the corbelled dome. Also, regarding the materials and constructive details, it is possible to add some more characterizing features like:

Fig.2 Relationship between the shelter and the landscape (Maestrazgo area – Spain)

• the lintel of the hut: its shape may be triangular, rectangular or half-spherical and formed by some shaped stones or by just one single large lintel (Fig. 5); • materials and finishing solutions of the hut: the structural stone may be of granite, limestone, slates, bricks or adobes. The finishing of the wall in human dwellings is rendered and occasionally lime washed, both on the interior to guard against insect intrusion and on the exterior in order to protect against the elements. In general, animal enclosures or temporary huts are not rendered or lime washed. Simple dry-stone walls and soil is employed in, for example, pigsty and goat compounds. Another variation consists of crowning the top of the hut with a finishing layer of soil. This solution is used above all in the northwestern part of the peninsula (Extremadura, Galicia, Portugal), for protection against damp (Figs. 6-7-8). Other interesting aspects are the different functions that these shelters may assume: • for human dwellings: this is the case in constructions for shepherds, peasants, watchers, etc. The constructions have chimneys, rendered and limewashed walls, niches for kitchen tools and crockery, as in bombos, barracas and chozos; • for animal dwellings: in this case the space is mainly for goats, sheep, etc., and rarely for cows. The walls are not lime washed, the soil of the ground and the unfinished details may be visible, as in barracas and chozos. • both for animal and human dwellings: in this case the plan is cell-like, with narrow passages between the quarters of the shepherds and those of the animals for the purpose of heating, as in ponts, barracas, chozos and bombos. • stores: the spaces are relatively smaller compared to those constructions intended for people or animals, as in espigueiros and hórreos. • wells: these constructions are generally smaller in dimension than human or animal shelters. Their purpose is to protect well curbs or springs, at flowing water level, covering the source and safeguarding against external threats (Figs. 9-10).

Earthen Domes and Habitats

Fig. 3: Possible layouts of corbelled domes; free standing, close to or upon dividing stone walls, with rear side to crag rocks

Fig. 4: Variants of some corbelled dome structures according to different combination of layouts and sections

Material and construction tecniques The huts are made using two different and compatible dry-stone techniques: the dry-stone walling system and also the corbelled dome system. The walls, built either in limestone (East of the Peninsula i.e. Catalu帽a, Baleares, Comunidad Valenciana and Castilla la Mancha), granite or slate (Northwest of the Peninsula i.e. Portugal, Extremadura and Galicia), are erected by bonding the stones without cement or mortar. The dome, called falsa b贸veda or falsa

c煤pula, is built in horizontal layers, where each stone slightly overhangs the previous. In some cases we may find adobe corbelled domes, but only in the area of Castilla-Le贸n, called Tierra de Campos, which has is a long-standing tradition of earth constructions in the world of vernacular architecture (Fig. 11). According to regional variations, we may briefly mention some of the most traditional examples in the Iberian corbelled dome constructions. Fig. 5: Different types of lintels, according to regional variations

Earthen Domes and Habitats Fig. 6: 3D section of a common corbelled dome structure of chozos and barracas made with piled stones

Fig. 8: Sequence of the constructive process of a circular corbelled dome structure, with spiral form ( in Andalusia, in Jaen province, the huts are named caracoles, meaning snails, due to the shape of the dome).

Chozos (Spain: Extremadura, Cantabria, Asturias, Aragón, Andalucía; Portugal: Alentejo). These are shelters for transhumant use. According to the season, shepherds move in for the summer and graze their sheep. During this time, these chozos may shelter several people living together in a space of a few square meters. Some constructions are crowned with a corbelled dome in granite or slate, while others with fired bricks. Generally, several of them have an external roof of the same slates, while others incorporate a traditional ceramic tile roof or even a traditional dome, not corbelled. Sometimes the roofs are protected against the rain by a layer of soil or turf, and they appear like huts with grass roofs. Sometimes the stone walls are covered with a clay coating. Usually the section is triangular and the vault is quite conical. These shelters are distributed particularly in the Cáceres (Juvanec 2008), Oviedo, Teruel, Almería (Muñoz Muñoz 2006), Jaén provinces, and along the North Atlantic Range. The name of these constructions changes in each province (, according to regional dialect and variations (i.e. cucos, monos, choucos, torrucas, chafurdones, caracoles, cubillos, tambores, catxerulos, and so on) (Fig.12).

Barracas (Spain: inner Provinces of Cataluña, Comunidad Valenciana, Murcia). These are stone shelters for shepherds mainly to protect themselves and their livestock from bad weather conditions or to keep animals. These may be shelters specifically for agriculture, normally built upon stone walls dividing agricultural plots and terraces. The vault is corbelled, with almost horizontal and overhanging stone layers. The single stones slope slightly outwards of the volume for water drainage. Generally, on top of the dome may be found a horizontal stone plate set in place with the aid of smaller stones. The shape outside varies greatly from one area to another. Nevertheless, it is possible to define three types according to the position of the building: free-standing volumes in brushy wooded hills, shelters partially built upon dividing walls of estates, shelters built with the rear side against a crag rock (Gironés i Descarrega 1999).These are typically found in Cataluña, (Martín i Vilaseca 1990) north Comunidad Valenciana region( Meseguer Folch 20002001; Castellano Castillo 2001), inner Murcia province and the east Aragon region (the latter are known as the Maestrazgo area) (Figs. 14-15).

Fig. 7: Sequence of the constructive process of a rectangular corbelled dome structure

Pozos (Spain: Aragón, inner Regions of Comunidad Valenciana and Cataluña, Andalucïa, Tenerife and Baleares Islands). These are stone constructions used as wells, with traditional corbelled dome architecture, using horizontal layers of overhanging stones. The dry-stone constructive system is perfect for the gathering of natural water, allowing ventilation and shielding from dampness or the arising of salts. The shape and dimension vary widely from one area to another, along the dry and arid regions of Spain, like the Canarias or Baleares Islands, where water is a real ‘treasure’ for peasants and shepherds. It is possible to define different purposes for the shelters: they may be wells, reservoirs, cisterns and so on, in some cases the constructions can be ice stores, not only water deposits, half excavated into the soil, mainly in the inner rural areas of Jaen, Zaragoza (Rivas 2004) and Valencia province (Rodríguez Cervera & Domínguez Bell-Lloch & Galliana Bondía 2004).

Earthen Domes and Habitats

Ponts (Spain: Baleares Islands). These are shelters for shepherds and sheep and basically can have two forms, according to older and more recent examples. The interior region of Menorca holds the most ancient typologies, built with incredible precision as half cubes on a circular ground plan and in two or three stepped heights (Juvanec 2001). They are made of grey stone and carry a capstone at the top or else a devotional cross. The larger and more recent shelters, meanwhile, are located in the northern part of the plains, where horses or bulls are reared (Calviño Cels 1999). Unlike the older structures, they are made with yellowish dressed stone of relatively equal dimension, perhaps smaller than in the case of the more ancient buildings. Because of increased needs, the more recent ponts are also larger, accommodating some ten horses, stepped on the outside and pre-dimensioned for safety reasons. They have a stepped form to the top and the terraces are filled with small pebbles (Fig. 16). The front wall is always completely flat and mangers are built into both sides of the entrance, with triangular compound lintels. Ponts always stand within an enclosure that may be a signal of their presence, as exceptional elements in the landscape of the Isle of Menorca (Baleares Islands), both for their dimensions and shape (Consell Insular, Mallorca 2004).

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Fig. 9: Layout and section of the triple corbelled dome structure of a bombo (Castilla la Mancha, Spain) Fig. 10: Layout and section of the corbelled dome structure of a pointed chozo (Comunidad Valenciana Region, Spain)

Fig. 11: Examples of earth architecture with corbelled dome in Tierra de Campos (Castilla y León, Spain)

Earthen Domes and Habitats 1 2

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Fig. 12: Layout and section of a chozo corbelled dome structure, closing to a yard (Extremadura, Spain) Fig. 13: Layout and section of a corbelled dome structure of a pointed chozo, with dividing areas for shepherds and animals (Comunidad Valenciana Region, Spain)

Fig. 14: Layout and section of a barraca corbelled dome structure (Aragon Region, Spain) Fig. 15: Layout and section of a barraca corbelled dome structure of Catalu帽a Region, Spain.

Bombos (Spain: Castilla La Mancha). These are stone shelters mainly intended for shepherds. They usually have a multiple cell layout (two or three cells) and corbelled vaults to cover the space (with a final layer of gravel). There are rooms both for people and animals connected with low doors so that the shepherd may monitor the livestock. The final shapes appears most natural, like simple stone piles in the flat landscape of the outskirts of Tomelloso (Castilla la Mancha Diputaci贸n de Albacete 2001), as if hardly made by the hand of man (Pedrero Torres 1999). The bombo has a corbelled construction on the inside and a frame outside, with filler in between. The frame serves only to ensure that the filler

does not leak out, and natural slippage of the material results in a harmonious shape. For this reason, due to the presence of filler the interior of the construction remains so peculiar and special in the context of shelter typology, (Juvanec 2001). The shape of the external roof derives from the disposition of the stones falling naturally down the slopes of the dome. Today, the roofs are whitewashed each year with lime (Fig. 17).

Almacenes (Spain: Galicia, Portugal: Montesinho). These are dry-stone constructions used as granaries with a corbelled dome system (that may or may not appear in the outer volume). Sometimes, ow-

ing to weather conditions, the roof is covered by slates to improve impermeability. The shape is rectangular, with a long and narrow layout (Lozano Apolo 2004).The shape outside varies greatly from one area to another but the base is always made by two or more vertical stones and with overhanging slates (protecting against rodents and animals). These are typically located in the Galicia region, on the Portuguese border, where they are known as hórreos (Caamaño Suárez 1999).

Earthen Domes and Habitats

Chozos De Viñas (Spain: Castilla Y León, Spain). These are adobe constructions, usually built within the surroundings of vineyards in order to watch over and look after the estate. The walls are built with adobe and less frequently with rammed earth, approximately 90 cm high. The vault is corbelled, projecting the adobe progressively, as with stone shelters (Alcalde Crespo 1994). The edges between the vault and the wall are covered and smoothed with dihedral corners to drain rainwater. There are some constructions without the perimeter wall, which start directly to corbel the dome almost from ground level, with just a 30 cm high stone basement. Both constructions have a finishing protection coating made with earth mortar, renovated every other year. Occasionally some vineyard monitoring constructions complete with chimney are still visible, evidence of human dwelling inside. Casetas De Pozos (Spain: Castilla-León). They also are adobe or brick constructions, in the vicinity of drinking troughs, used to cover and shelter to wells (Sánchez del Barrio& Carricajo Carbaio 2005).The peasants and shepherds guard the well curb against animal pollution with such protective structures built with stones or even adobe. The vault is a corbelled, with progressively projecting elements. Outside of the construction but close to them, there may be found some basins or drinking troughs for livestock, directly fed with water through a channel from the curb (Fig. 18).

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Fig. 16: Layout and section of a corbelled dome structure of a pont (Islas Baleares, Spain) Fig. 17: Layout and section of double-corbelled dome structure of a pointed bombo (Castilla la Mancha, Spain)

Earthen Domes and Habitats

Casetas de Labranza (Spain: Rioja- Navarra- País Vasco). These buildings have much the same constructive features as chozos but are destined for a different purpose, in that the peasants use them to store the tools, equipment and instruments, etc., of their daily work. The inner space of the shelters, for this reason, may be divided according to the type of tools stocked. They are typically found in rural northeast areas of Spain, like Álava province, southern País Vasco and the southern Navarra region (Fig. 19). Espigueiros (Northern Portugal). These are stone constructions used as stores for drying corn (seldom grain). They usually have thatched roofs over the corbelled dome, or sometimes the corbelled vault with horizontal layers of stones appearing through to the exterior. These dry-stone shelters are ideal as they allow the breeze to permeate and facilitate the drying of corn. The shape outside varies considerably from the circular to the rectangular. The dry-stone compositions are bonded with impressive detail, as if not stone masonry but wood joinery. They are typically located in the north of Portugal (Moutinho 1979). Dólmenes and Tholoi (Andalucía). Some of the oldest examples of corbelled dome architecture can be found in the Magina area, a nature park, in the Almeria province (Andalucía). Here we have traces of Iberian villages with some archaeological remains of ancient Tholoi and Dolmenes structures, some of them close to cave typologies, with corbelled dome sheds (Escobedo Molinos 2001). Evaluation of the state of conservation Some of the most important problems related with corbelled dome architecture may be summarized in the following points: • the huts are no longer in use in the main part of the Iberian Peninsula; • very often shelters are under private ownership, not always “protected” by laws, rules or regulations; • the research on vernacular architecture and the associations of professionals are not always effective enough or powerful enough. There is the problem of localism and a lack of unification of works and research;

• there is also a lack of transmission of information between local welltrained professionals and preservation organizations; • local professionals are not always involved in the research; • only in few cases are professionals prepared and trained to maintain and preserve the corbelled dome; • in some cases, the corbelled dome system is treated with a rather folkloric approach and not a real scientific attitude in publications; • in general we can see the loss of knowledge concerning this construction technique and the presence of too few local-technical workshops (handson training). At the same time, a reflection may be proposed on the pathologies and the degradation of these vernacular shelters: • shelters made with dry-stone techniques can survive poor atmospheric conditions (in this case there are no such problems as pathologies related to the material, joints and mortar); • the presence of animals can damage the structure if not maintained properly. In these cases the huts usually suffer a lack of volume and stones; • the compact system of the corbelled dome may be seriously damaged in the case where some parts are missing (holes, fractures). The loss of a part of the overhanging vault may seriously affect the well-being of the hut; • huts are always in aggressive environments that may attack the structure (dampness, fungus, biological attacks, etc.), although in some cases this risk is reduced by the absence of windows and openings. Fig. 18: Well made using bricks with a coated corbelled dome structure (Castilla y Leon, Spain)

Meseguer Folch, V. & Castillo, J. S. 2001, El Patrimonio Etnológico agrario de Benicarló, Centre de Estudi el Maestrat, Castellón. Meseguer Folch, V. 2006, Arquitectura popular de pedra seca al terme de Vinarós, Centre de Estudi el Maestrat, Castellón. Meseguer Folch, V. & Castillo, J.S. 1997, El Patrimonio Etnológico agrario de Canet Lo Roig, Ed. Centre de Estudi el Maestrat, Benicarló. Moutinho, M. 1979, A Arquitectura popular portuguesa, Ed. Estampa, Lisboa. Muñoz Muñoz, J. A., 2006 ‘Los refugios de piedra de Uleila, Sorbas y Lubrín’, Alfa , no.13, pp.8-14, Sorbas, Almeria . Oliver, P. 2006, Built to meet needs cultural issues in vernacular architecture, Architectural Press, Oxford. Pedrero Torres, J. 1999, Inventario de los bombos del término municipal de Tomelloso, Ediciones Sobriet, Ciudad Real. Rivas, F. 2004, Construcciones pastoriles en la comarca de Monzón, Centro d’Estudios de Monzón y Cinca Medio Ed., Huesca. Rodríguez Cervera, L. & Domínguez Bell-Lloch, J. & Galliana Bondía, J.V. 2005, Els catxirulos de Benaguasil: una artesanía de pedra en sec, Ayto. Benaguasil, Benaguasil, Valencia. Sánchez del Barrio, A. & Carricajo Carbaio, C. 2005, Arquitectura popular, construcciones secundarias, Centro Etnográfico Joaquín Díaz, Valladolid. Fig. 19: Layout and section of a caseta de labranza corbelled dome structure, close to a well (Navarra Region, Spain)

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List of References Alcalde Crespo, G. 1994, Palencia, barro, madera, piedra, Ed. EST, Palencia. Asquith L. & Vellinga M. 2006, Vernacular Architecture in the Twenty-first Century- Theoryeducation and Practice, Taylor and Francis, New York. Arquitecturas de piedra en seco 2000, Actas del VII Congreso International de Arquitecturas de Piedra en seco. Peñíscola, 12-14 Octubre 2000, Ed. Centre d’Estudis del Maestrat, Valencia. Architettura in pietra a secco 1990, atti del I Seminario intenazionale Architettura inpietra a secco, Noci-Alberobello, 27-30 settembre 1987, Ed. Schena, Bari. La Pedra en sec, obra, paisatge i patrimoni 1994, IV Congrés Internacional de Construcció de Pedra en Sec, Consell Insular, Mallorca. Construcció de pedra seca 2005, Actes del 1er colloqui internacional de construcció de pedra seca. Barcelona 6,7 i 8 de juliol de 1990, Aguazul Ed., Tarragona. Actes del I Congreso Nacional de Arquitectura Rural en Piedra Seca 2003, Albacete 2001, Diputación de Albacete, Albacete. Bóvedas y cúpulas de ladrillo 1977, Instituto Eduardo Torroja Ed., Madrid. Els Homes i les Pedres. La pedra seca a Vilafranca: un paisatge humanitzat 2002, Ed. Disputación de Castellón, Castellón. I Congreso Nacional de Arquitectura Rural en Piedra en Seco Zahora 1993, Revista de Tradiciones populares Servicio de Publicaciones, Disputación Provincial de Albacete, Albacete, vol.1, n.38. La construcción de pedra en sec a Mallorca 1994, Ed. Documenta Balears, Mallorca. L’habitatge temporal, l’home i la pedra II 2004, Universitat de Valencia Ed., Valencia, vol. 2. Libro de la piedra en seco 2002, Edicions de Turismo Cultural Illes Baleares, Palma de Mallorca. ‘Parcourse de pierres’ 2003, Cahier de l’Aser, no.11, Ed. Culture 2000,. Bassegoda Nonell, J. 1989, El Gran Gaudí, Editorial Ausa, Sabadell, Barcelona. Bosch Navarro, M. D. 1995, La forma cúpula en la arquitectura y en la naturaleza: valores funcionales y simbólicos como motivo de una reflexión plástica personal, Phd final work, Universidad Politécnica de Valencia, unpublished. Caamaño Suárez, M. 1999, As construccions adxectivas, Ed. Caderno do Pobo Gallego, Santiago de Compostela, vol.9. Calviño Cels, A. 1999, Les Barraques de Llucmajor, una arquitectura popular, antropología i etnografía de la foravila llucmajorera, Ed. Fodesma, Mallorca. Castellano Castillo, J. J. 2001, Los cucos de la Sierra de Enguera, informe de su inventario y restauración, Ayto de Enguera. Escobeo Molinos, E. 2001, ‘Cuevas de piedra, caracoles y monos’, Mágina, Asociación para el Desarrollo Rural de la Sierra Mágina. Cambil, n.11. Escrig, F. 1994, La cúpula y la Torre, Fundación Centro de Fomento de Actividades arquitectónicas, Sevilla. Gironés i Descarrega, J. 1999 L’art de la pedra en sec a les comarques de Tarragona, Disputació de Tarragona Ed., Tarragona. Juvanec, B. 2001, Shelters in stone, research, short version, Liubljana University Ediciones, Ljubljana. Juvanec, B. 2008, Hut of Extremadura, Arte Ediciones, Extremadura. Lozano Apolo, G. 2004, Hórreos, cabazos y garayas, Lozano y As. Ct. Ed., Vigo. Martín i Vilaseca, F. 1990, Les Construccions de pedra seca a la comarca de les Garrigues, Ed.Ramón Serra i Batlle Pagés, Lleida. Meseguer Folch, V. 2000, La piedra en seco en las comarcas del norte de Castellón, Ed. Centre d’estudis del Maestrazgo, Castellón.

Earthen Domes and Habitats

Ă&#x2030;cole dâ&#x20AC;&#x2122;Avignon, France

Fig. 1: Le Contadour, Provence

Dry-earth buildings have been found in the south-eastern French region of Provence since prehistoric times with construction reaching a peak between the 16th and 18th centuries. Relative poverty, and its position as a rural area formed by a number of plains of extensive agriculture and pastoral farming, made Provence an ideal area for dry-stone building. This is the simplest construction method, where man intelligently makes use of the only material readily at hand at the required site of building: stone. Dry-stone buildings have a predominantly agricultural end: sheepfolds or stables, granaries, storage tanks and buildings for wine making. Apart from these traditional uses, one also comes across examples of dwellings and defensive observation posts that were later converted to hunting stations. Though rare, stone buildings can also be found serving as lime ovens and walls for bee keeping. This is a perfect example of recycling, since the stones used in building are collected at the site itself, the stones being found on site with no need for transportation. This task generally has two purposes: clearing fields of stones to enable the growing of crops and also the gathering of material that will be used to build the shelter at the edge of the field, enclosure walls and threshing areas. Nothing is predefined; the builder uses what materials he finds to hand. However, if the stones found on site are to be used for building, they are most often sorted and organised by thickness and length before building begins. This allows the building process to develop with a minimum of extra thought and optimal use of the stones. On the Vaucluse plateau, the plague wall is an uncharacteristic construction far removed from the initial reasoning behind dry-stone building. The wall was built in 1720 in an attempt to contain the plague brought to Marseille on the ship Grand Saint-Antoine. The wall is 27 km long and contains various additions such as sentry boxes, guardrooms, pens and shelters for animals.

A logical way of using the earth Beyond and also prior to the construction of buildings, the essential act of constructing in dry stone springs from an initial desire to inhabit and make best effective use of an area: - Development of the land: for a field to be farmed by plough, it will be necessary to remove the stones that are scattered around. Taking away these stones from the field results in the forming of a mound of stonesÂ (clapas in Provencal dialect). So as to most effectively inhabit the land, some of these piles of stones are therefore used for building, thus creating a process of sorting the stone. - Making the best use of the earth; levelling farmable fields and therefore increasing the amount of farmable surface area requires the building of retaining walls. Dry-stone building is ideal for this use, providing porous supporting walls that allow for the drainage of water. - Travel; dry stone also plays a role in the development of progress across the land, between villages, from the basic laying of a stone path to the building of staircases, whether they be suspended stepping stiles, integrated into the thickness of the wall or perpendicular to the terraces.

Earthen Domes and Habitats

Dry-stone buildings in Provence

Patrice Morot-Sir

Earthen Domes and Habitats

Circular plans

Quadrangular plans

Aberrant plans

Fig. 2a: Plans of dry-stone buildings

The various stones The stones are sorted in preparation for how each stone will be used in the building; each stone has a different usage and therefore a different name: - Facing stone; the main stone used for the facade and which gives the wall its final appearance. The stone, being outwardly visible, needs to have a good clean face. A facing stone with two clean faces will be kept for a corner stone. - Through stones; joining the two sides of a wall, essential for making the construction stable. As a structural element, the through stone must be robust and long. - Top stones; to cap the top of the wall, they are used solely for high or low walls. Building technique, from the wall to the vault First the walls are built. With this building technique the walls have to be built thickly, between 45 and 120 cm in thickness, gradually thinning out as the wall gets higher. The stones are mostly laid perpendicular to the direction of the wall (along the longest side of the stones). The wall is mostly made of two outer facing walls with a rubble core filling. In all cases, the facing stones in both outer facing walls are attached by through stones (a large stone keystone), which cross the width of the wall and are placed at regular intervals along the wall (ideally one every square meter). If the stones are not long enough, two half-keystones can be used with overlapping ends that bond strongly together. Gradually, the beginning of the vault starts to replace the continuation of the wall building.Â After the levelling course, which is placed at around 2 meters high, the wall starts to lean inwards and creates a vault. Each course is auto-

stable. The higher up in the vault, the less stones are required and the stones used become flatter in shape. Christian Laussure distinguishes between two main kinds of vault: the outward inclining corbelled stone vault and the mortarless keystone vault. The outward inclining corbelled stone vault This type of vault, when constructed on a circular basis, obeys two principles: the corbelling technique and the method of placing the stones tilting outwards. The corbelling technique consists of placing the stones in the same circular layer with a slight overhang over the previous course, like corbels. It is of the utmost importance that the centre of gravity of each stone should be kept within the depth of the underlying stone so as to obtain balance. Balance is obtained by loading the tail of each corbel to act as a counterbalance and to lessen the weight of the overhang by trimming them. It is also necessary for the corbels to be tapered so that their interface should radiate towards the centre of the circle. The basic principle of stones laid tilting slightly outwards consists of giving the stones in each course a slightly outward slope (about 15Â°). (If the stones were laid flat, they would strictly speaking result in a tas de charge vault made of horizontally laid courses). This inclination causes the slabs inside each course to buttress each other in a horizontal plane, resulting in a polygon of forces being closed: each course thus becomes self-binding and autonomous while being borne by the one below. The outward thrust exerted by each course is cancelled by piling up on top of material that serves as abutment. The succeeding layers curve inwards gradually until they almost meet, the final layer being topped by a single capstone or by several stones placed side by side. No formwork or framework is required in this vault with horizontal stress (as opposed to the conventional keystone vault with vertical stress). While the removal of the keystone from a mortarless keystone vault will bring about the fall of the whole vault, the final capstone in a corbelled vault can be removed without causing the vault to collapse. The mortarless keystone vault The mortarless keystone vault is much less widespread than its corbelled counterpart. A mortarless keystone vault is made of arch-stones, (cornershaped stones) a section cut would show that the joints between each layer (the angled sides with which one arch stone leans against the others either side) converge towards the same point. The dry-stone mortarless keystone vault is not a vault made of cut stone

Fig. 3: Le Contadour, Provence

Earthen Domes and Habitats

Fig. 4: Le Contadour, Provence

Earthen Domes and Habitats

voussoirs in courses, the manufacture of which is beyond the means of drystone builders as it requires studies in stereotropism, it is composed instead of slabs that are flat or worked with a hammer, or rough-cut blocks laid on a provisional formwork. A keystone cradle-vault is made with parallel layers of bricks and a wooden formwork is used – made with adjoining boards that are supported by cross braces and string-pieces and placed on the corbels or on a scarcement ledge at the base of the vault. They are moved across the support so that construction of other lengths can be continued. The vault follows the shape of the formwork. At the vault’s inner curved surface, a section cut shows that the layer joints are aligned and parallel to the rooftop line. To build a domed mortarless keystone vault with arch-stones that are either flat slabs or stone worked by hammer, or rough-cut inner surface blocks that are rudimentarily chiselled into shape, a hemispherical former is made and the cross braces are incrusted into the top of the vertical wall. Once the vault finished, the former is removed. This type of vault is closed with a keystone. A section cut at the domed mortarless keystone vault’s inner curved surface, would show that the joints between layers are concentric.For small buildings with a domed mortarless keystone vault, a wooden former was not used but rather piles of stones or facines were used and removed once the vault was finished. What is the future of this kind of constructional heritage? Considered as part of the heritage of an area, what is the future for dry-stone building and what is the future for existing structures? Many solutions exist and a middle ground may be found between the extreme views of those who celebrate this kind of building fanatically and those who oppose and hold condescending views of such techniques. As a starting point, let us consider dry-stone building for what it essentially is: a technical response befitting the times and a solution that matches the characteristics of an area (mainly building materials), a technical solution that carries a real message with regards to the economy of means and a way of living in harmony with the earth. Ecological understanding of the risks at stake due to energy creation has raised the general awareness of man’s impact on the environment, not least the impact of building. Dry-stone building is not a universal response but was certainly an example of eco-construction way ahead of its time. Figs. 7-8-9: Le Contadour, Provence

inside

In this kind of building technique, as in other traditional techniques, industrialization has lead to a great loss of technical expertise. Thanks to a relatively recent bout of activism, the recovery of these skills is today being encouraged by our present understanding of man’s impact upon our planet; such craftsmen cannot live on their skills if there are no economic possibilities, as there can be no supply if there is no demand. Dry-stone building is symbolic of traditional building techniques, of how intelligently local building materials were used, and of how intelligently the construction was built to work with the land, to the geographical situation and to the local history. There are surely lessons to be learned for the future from this kind of building. List of References

Architecture Traditionnelle Méditerranéenne 2002, Ecole d’Avignon, Avignon Coste, P., Cornu, C., Larcena, D. & Sette R. 2008, Pierre Séche, Le Bec en l’air, Dominique, Fl. 2009, 25 balades sur les chemins de la pierre séche, Le Bec en l’air Lassure, Ch. 1993, Essai d’analyse architecturale des édifices en pierre sèche, L’Architecture Rurale en Pierre Sèche, suppl. n° 1, pp. 1-27 and 36-60, Paris, CERAPS Massot, J.-L. 2004, Maisons Rurales et vie paysanne en Provence, Actes Sud, Marseille

type 1

Fig. 10: Auribeau, Provence

Fig. 2b: Sections of dry-stone buildings Fig. 2c: Detaile section of a dry-stone building

G M g m

Earthen Domes and Habitats

In the ancient Hellenic world, beehive corbelled domes reached a notable level of technical evolution very early on and created not only brilliant monumental forms, such as the Late Minoan tombs in Crete and the famous Thesaurus of the Mycenaean kings in Peloponnesus, but also simple adobe or stone habitats widely spread over the historical Hellenic world from Macedonia to Cyprus. This tradition survived in the following centuries with no significant innovations from then on, though the relation to the ancient forms is not always clear. In the case of dry-stone corbelled buildings, in particular, the precise date of construction is usually uncertain, since, though their age understandably cannot exceed two or three centuries, they maintain the unchanged primordial forms. Here we are focusing on corbelled dome constructions of Greek vernacular architecture during the last millennium, with a concise reference to some earlier examples of the AD era or before, still in use at that time. Geography, natural environment, socio-economic context Corbelled dome habitats of southern Greece are strongly related to dry and arid climatic conditions unfavorable to wood production; they can be found mostly in small, rocky islands and in barren, windy landscapes, often at high altitudes where the sole construction material remains stone. Stone is usually abundant in such harsh grounds anyway, in different types of rock, limestone, schist, etc. (Fig. 3). Vernacular corbelled dome constructions are scattered around the south of Greece in regions close to the sea; functionally similar forms in the north of the country are the paraboloid straw huts of nomad pastoral clans like the Sarakatsani. These huts are considered to be prototypes of the primitive stone and adobe built beehive dome forms. In modern times corbelled dome buildings can be found in Dodecanese, on the

Hellenic Society, Aristotle University of Thessaloniki, Greece

Fig. 1: Diffusion of corbelled building culture

Mani peninsula, on some of the Ionian Islands and, mostly, in Crete. Their geographical distribution is therefore localized along an Ionian IslandsCrete-Dodecanese line, as part of a tradition diffused from the western Fig. 2: Corbelling dome architectures in Greece in the AD era

THRACE

MACEDONIA

EPIRUS Ioannina Corfu Igoumeni 12 Lefkada

Larissa THESSALY Volos 0 CENTRAL GREECE

AEGEN ISLANDS

EUBOBEA

IONIAN ISLANDS

Patras 1 11 Zakynthos PELOPONNESE

Athens

CYCLADES

Aeropoli DODECANESE 8

9 9

Heraclion 8 7 CRETE

6 Karpathos

Earthen Domes and Habitats

Corbelled dome architecture in Greece

Maria Arakadaki

Urban and architectural morphology and function In examples of Greek corbelled dome architecture, no ‘urban’ character is discernible; these are usually desolate buildings scattered among fields and remote pastures. Occasionally, when a number of them are grouped together in a region, they do present some kind of remote connection to each other, as happens in certain groups of mitata in Crete or in the voltoi “village” of Englouvi in Lefcada. Otherwise, the only connection of note concerns the grouping of 2-3 domed units together serving as habitation and as product storage (Fig. 8). Even in the rare cases of corbelled settlements, presented below, the edifices are situated haphazardly and separated from one another.

Earthen Domes and Habitats Fig. 3: Geological formation and corbelling construction: landscape from mount Idi, Crete

Mediterranean to the Near East: Asia Minor, Syria, Palestine and the Sinai peninsula (Fig. 1). Corbelled forms are unlikely to be seen in Cyprus, though local earthen bricks terraced vernacular architecture suggests a connection to the raw earth examples of the Euphrates region. Moreover, the corbelled dome buildings of southern Greece are almost exclusively related to rural life, mainly to that of shepherds, such as the mitata of Crete, but also to that of peasants, such as the voltoi of Lefkada (Fig. 10a-b). They have an annual circle of use, clearly of a seasonal character, which follows the natural rhythm of the changing seasons, the perpetual migration of people from the mountains to winter pastures and vice-versa, and the successive phases of land cultivation and harvest. These are temporary shelters, closely linked to the agricultural society and economy, in direct response to the natural environment. In Greece there are no permanent corbelled dome villages like the Italian trulli di Alberobello or the Syrian settlements of the Halep region.

Architectural morphological analysis As stressed above, the corbelled dome architecture of southern Greece concerns mainly dry-stone structures. This also strongly influences morphology, since dry-stone masonry requires an outside escarpment for purposes of static. Naturally, the escarped forms are often applied even in constructions with mortar, giving corbelled buildings a unique character of their own. Sometimes the structure may be so modest that the result resembles little more than an irregular mass of stones. The external form does not always correspond to the internal structure; square or rectangular volumes can equally be covered with curviform corbelled domes. Some typical cases of corbelled architecture along the already mentioned Ionian-Crete-Dodecanese line are presented below. “Mitata” and “calyvia” in Crete In Crete, seasonal shepherds habitats, called mitata, fall into two basic categories: the truncated-conical or cylindrical corbelled type, found only at high altitudes (1,500 meters asl or more), on the central mountain range of Idi or Psiloritis and on the White Mountains or Madares to the west of the island (Fig. 4); and the mitata of the eastern regions, which are rectangular and terraced. Small, structurally modest mitata situated on mountain slopes at lower altitudes served as temporary dwellings along paths to and from winter pastures. Corbelled mitata have close similarities to the Minoan corbelled tombs discovered in Crete. The use of the term mitato, deriving from the Latin metatum (rural military habitation), also suggests that the forms in question have their origins in the distant past. A possible reason why only mitata aged 150-200 years sur-

Gaeon, Tholos sanctuary, Voura, Peloponnese (after N. Moutsopoulos),

Drakospito on mount Ochi, Euboea

Krefti, Nisyros island (after D. Vassiliades)

Spilia, Telos island

Kypha, Chalki island

vive is that whenever a mitato was destroyed over time and by climatic conditions, the huge stone masonry served as a precious raw material for new constructions. The most technically advanced structures are the corbelled mitata (about 25 in number) on the plateau of Nidha (1,700 meters asl) on Psiloritis, and those in the Rouvas Wood on the south eastern slopes of the same mountain. On the White Mountains, besides a few circular mitata, rectangular examples covered with small corbelled domes supported by arches, are a local particularity (Fig. 5). Terraced mitata, nevertheless, are also more frequent here. The term mitato usually describes a group of 2-3 corbelled domes (Fig. 5), including a coumos (habitation for men), a space for cheese-making and a tyrokelli or kleidospito for the preservation of dairy products, together with an open-air dining room and an ample yard with a dry-stone enclosure (mandra) for the everyday routine of milking ewes (Fig. 6). A typical domed single coumos has a maximum internal diameter of 3.5-6.5 meters with a height of 2.8-4.5 meters and huge walls 1,0-1,90 meters thick. The only opening is the narrow entrance, with in some cases a central opening at the top of the dome for air circulation. Internally there is a stone-built platform for seating, a fireplace for cheese making and a smaller one for cooking. A mitato complex usually belonged to a clan of shepherds, brothers or cousins, who lived there from May to November. A deep change in shepherds lives in the decade of the 1980s, namely the construction of roads for automobiles up to the mountains, brought the use to an end. The ethno-anthropological context concerning men working in the mitata, and the detailed customary regulations about the sharing of dairy products among them, is too rich to be covered here. Corbelled forms found in eastern Crete are the so-called calyvia, small scale corbelled dry-stone huts of primitive structure (Fig. 15b) with diverse types of ground plan (circular, ellipsoid, horse-shoe shaped), used as temporary shelters for 1-2 persons each (pastors, cultivators, hunters), in the dry and windy country landscapes along the rocky northern shores of the island. The â&#x20AC;&#x2DC;Palatiaâ&#x20AC;&#x2122; settlement of Saria Saria is the name of an arid rocky islet close to the northern end of the island of Karpathos (Fig. 9). On the east coast of the islet there is a small

Earthen Domes and Habitats

Conaki, straw made hut of Sarakatsanoi nomads, Central/ North Greece (after C. Kouremenos)

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Earthen Domes and Habitats Venetian watchtower Calyvi

Mitato (Crete)

gorge, extending down to an isolated anchorage. A Roman-paleochristian town, now in ruins, once existed here. A second settlement is distinguishable on a bare hill to the north of the site of that town, its sparse, peculiar little houses circulated by a dry-stone fortification wall. Most of the houses are rectangular and vaulted; a few of them follow a second, very interesting type: cubic outside, with a beehive corbelled dome over an interior circular ground plan of c. 2.5 x 2.5 meters (Fig. 9a). All these small dwellings, most of them with entrances protected by tiny vaulted porches, are dominated by a large edifice of the second type with a cylindrical external form which presents two grades towards the top (Fig. 9b). Its appearance was inspiration for the placename, Palatia (palati: palace, mansion). The houses are stone-built with strong mortar; a thick layer of hydraulic mortar covers the domes. The building techniques would seem to be quite sophisticated. In this desolate and peculiar medieval village researchers detected strong influences from the architecture of Syria (Halep region) and of southern Turkey (Harran region), though the construction material of the latter is earth. The settlement is dated around the years of largescale pirate invasions in the Aegean, before 1,000 ad. One should bear in mind that the sea channel between Karpathos and Crete has always been a favorite ambush point for Muslim pirates, possibly the founders of the little village of Saria. The â&#x20AC;&#x2DC;Voltoiâ&#x20AC;&#x2122; settlement in Lefkada On a plateau near the village of Englouvi, Lefkada, Englouvisan women still maintain the traditional cultivation of a local species of lentils, considered to be one of the best in the world. With this and other agricultural occupations is connected the seasonal corbelled settlement of Voltoi. Its Italian name (volto: arch, vault), and the nearby existence of the small rural chapel of St. Donatus, gave rise to the opinion that the remote settlement was founded in the Venetian era by local people suffering from pirate raids and from the heavy taxation imposed by Venetian, and later by English, sovereigns. Indeed, the solid structure of the domes with the use of mortar to give a certain permanence over time, supports this hypothesis. About 50-55 voltoi are preserved on the plateau , together with a score of voroĂŹ (small dry-stone huts). They have circular or ellipsoid ground plans and corbelled domes which, facilitated by their construction with mortar,

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False-vaulted country-chapel, Mani

Venetian vardiola, piramidoid-domed watchtower, Zakynthos (after D. Zivas),

have an almost hemispherical shape with a height not exceeding 3.0-3.5 meters from the floor. The strength of the local corbelled constructing tradition is obvious in the fact that, up to the end of 1960s, Englouvisan boys knew how to build tiny dry-stone voltoi with small stones and broken tile pieces. The one who completed his own without it falling in was held to be the winner. The groups of voltoi constitute of 2-3 corbelled spaces with a threshingfloor for each. They are wisely placed on terraces up the slope to take advantage of the incline for protection against climatic conditions, without preventing the wind draughts that are essential for winnowing of harvests (Figs. 10a-b). The storage of straw was simple, through special openings left on the domes of the barn chamber. The rest of the chambers were designated for the use of people, the stabling of animals and storage of crops. Isolated units or groups of voltoi are also spread over the countryside of Lefkada. Origins and influences: a diachronic approach The origins and connections of modern to primordial Greek corbelled forms are not always clearly visible; some examples of the evolution of corbelled dome constructions from ancient to modern times are cited below. The probably Hellenistic ‘Drakospita’ of southern Euboea The Drakospita (Dragons dwellings) are square or rectangular megalithic structures with solid corbelled walls more than 1.0 meter thick, dry-stone built with cyclopean ashlar stones and covered at the top with huge schist slates. The most significant among them is situated on the summit of Mount Ochi (Fig. 11), at an altitude of 1,400 meters. The internal dimensions are of 4.80 x 9.80 meters and it is considered to be a kind of peak

Voltos, Lefcada.

sanctuary. Other drakospita of similar size (about 4 x 10 meters, or 4 x 4 meters the square examples), though of less impressive structure (Fig. 12), are found in the surroundings of the town of Styra and are likely to have had a diachronic use by peasants and pastors of the region. The Hellenistic beehive tholos ‘Gaeon’ of Voura, northwestern Peloponnese The Gaeon (sanctuary devoted to the goddess Gaea) of the ancient town of Voura is an impressive beehive tholos with an interior diameter of 5.1 meters and a height of 6.25 meters (Fig. 13), dated between the great earthquake of 373 BC and the years AD 173-174, the date of the noted traveller Pausania’s visit. Later the monument was incorporated by the post-Byzantine Monastery of St. Trinity, for which it served as a dining room and also as a model for the shape of its church. Gaeon is a key monument, an important link between ancient corbelled constructions and the vernacular buildings of modern Greece. Small-sized Venetian watchtowers in Crete (16th-17th cent. AD) Of a probable large number of watchtowers erected by local guardians all around the Cretan seacoast, only rare ruined examples survive as testimony to a type of edifice following the form of the truncate-conical mitato. These buildings were constructed using mortar, with an interior diameter of about 3.0 m and a height of 2-2.5 m. The covering was of hemispherical corbelled dome, protected with an external layer of hydraulic mortar coating (Fig. 14). ‘Kyphes’ and ‘kreftes’ in Dodecanese Besides the above-mentioned case of Saria, corbelled constructions in Dodecanese are located in several of the smallest and most barren islands, such as in Nisyros, Telos, Chalki and, close to the latter, the islet of Alimnia.

Earthen Domes and Habitats

Palati, Saria islet (after N. Moutsopoulos),

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corbelling mitata calyvia

Fig. 4 Geographical distribution of corbelling dome structures in Crete island.

6.2. dry-stone mandra enclosure Fig. 6a: Dry-stone mandra enclosure

Fig. 6b: Pinakopetra (pinaki means bucket for milking) Fig. 6c: typical access

Fig. 5: Xirouchoghianniâ&#x20AC;&#x2122;s rectangular corbelling domed mitato, Asfendou, White Mountains, West Crete (after Deligiannakis): 1 coumosmen residence, 2 tyrokelli (cheese deposit), 3 yard, 4 mandra (yard for milking the ewes) Fig. 6: Typical mitato with a single coumos from Nidha plateau (plan after Vallianos)

Fig. 7: Cross section of the mitato of Fig. 6

1 1

6.3. Pinakopetra (pinaki=bucket for milking).

Synopsis of typology In Greek lands, a crossroads of Mediterranean civilizations throughout history, most types of corbelled domes have appeared, with the exception perhaps of the conspicuous conic examples, as the trulli type (Fig. 17). Cylindrical and truncate-conical volumes enclosing beehive domes (mitato type) are the most frequent. Sometimes they have an outside square plan, for purposes of static (as in the ‘Saria’ case). There are also ellipsoid domes on elliptical or rectangular volumes (drakospito type), but in this particular case the dome is mostly truncated at the top and covered with a terrace (kypha type). ‘Corbelled dome’ is not the exact term here, but rather pseudocupola, corbelled side walls leaving a void at the top, then covered with stone slates or beams and a layer of earth (Figs. 15-16). It must be stressed that the practice of corbelling the side walls to facilitate covering of an edifice with slates and terrace is commonplace in South Aegean islands, especially in Cyclades. Fig. 8: Examples of grouping of the parts of a mitato. C coumos, T tyrokelli or kleidospito, X xocoumos (chamber leading to main coumos), k open-air or terraced calyvi, a open-air dining-room, m mandra, E dry-stone country chapel. Double mitato from Rouvas Wood, Mount Idi

MULTIPLE

ELLIPSOID

103

RECTANGULAR T

C a T

DOUBLE

SINGLE EXPANDED

SINGLE

CIRCULAR

Earthen Domes and Habitats

In these parts, as in the whole of the Aegean, the great pirate raids of the 8th-9th centuries AD forced people to take refuge far from sea shores for many hundreds of years. In Chalki and Alimnia, kyphes, humble shelters, (kypha: head in ancient Greek and kyphòs: curved) are scattered across the countryside, dry-stone built and almost indistinguishable from the surrounding rocky landscapes. The ground plan is usually ellipsoid, resembling the form of certain calyvia of Crete and Mani, and also the Valearian navetas. They have dimensions of 6-8 x 2-2.5 meters and very thick walls of massive cyclopean stones (Fig. 15a). They were in use up to the first decades of the twentieth century, as seasonal habitats in the sowing and harvesting periods. In Nisyros, kreftès (adj. Kryfòs: hidden) are found, oil and wine dry-stone warehouses, usually grouped with seasonal habitats and barns, called spiladia (small caves). In the circular krefti of Fig. 16 the interior diameter is of 3.0 meters, which at the top of the beehive dome is reduced enough to be covered with one large slate and a layer of earth above. The nearby rectangular spiladi has corbelled walls and the narrow spaces between its supporting arches are covered with small false vaults.

C T

T k

X m1 a

C1 m

k C

m C1

C2 E

T a

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0 1

Figs. 9a: Corbelled domed types B1 and B2 (after Moutsopoulos)

Figs. 9b: Corbelled domed types B1 and B2 (after Moutsopoulos)

Fig. 9: Saria, Palatia, site of the settlement

SARIA ISLET

Palatia

Materials and building techniques Materials Corbelled dome vernacular constructions are made of stone, mostly dry stone and CARPATHOS ISLET only occasionally employing the use of mortar. The raw material is usually abundant in the surroundings where only the hewing of a rock to pieces is necessary. At CASOS ISLET high altitudes stone fragments are naturally produced by the disintegration of rocks by frost (Fig. 18). Schist stones are ideal for corbelled constructions, since they can be gathered on site and put to use immediately, with hardly any need for further tools. Understandably, corbelled architecture is more frequent in regions where schist rocks are present. Analysis of building techniques Though the constructions in question are often modest in structure, an

examination of the techniques behind these forms reveals constructional skills that were far from primitive. The case of the Cretan mitata is the most sophisticated and didactic from this point of view. Their construction proceeds for the inner and the outer parietal surfaces simultaneously, the intermediate space filled with smaller stone fragments. The corbelling of the dome starts at a height of only 1.2-1.5 meters. The flat stones used are placed with a slight inclination towards the outside, for the prevention of penetration by rainwater. Furthermore, outside the main wall ring, many of them have a second dry-stone ring (exofillo), for better acceptance of the pushing forces of the domes and support of the structure when frost causes a loosening of the joints of the stones (Fig. 20). A detailed mathematical and mechanical analysis of their static function, elaborated in the National Technical University of Athens (Fig. 20), has proved that the dimensions of the mitata, the escarpment of their side walls, the length and thickness of every single stone of their domes, the projection of the rings of corbelling above each other and the proper inclination of the stones towards outside, are all perfectly balanced for

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Fig. 11: Drakospito on the top of mount Ochi, Euboea

0 1 2

Fig. 10a: Typical layout, after Apostolou (1 sitting-room, 2 stall, 3 barn, 4 threshold-floor)

Fig. 12: Square drakospito at Pali Laca, Styra, Euboea. Plans (after Moutsopoulos) Fig. 13: Gaeon, tholos sanctuary at the ancient town of Voura, Peloponnese. Section (by Moutsopoulos)

the ideal function of the whole. The original masons, fully exploiting the possibilities of dry-stone building, have produced technically exemplary results. In rectangular edifices the corners have a special structure with projecting slates, to safely accept stepping of curviform corbelled domes. The case of corbelled walls covered with slates or stone beams and terracing is technically simple, hence adopted in modest structures, such as kyphes of dodecanese and certain calyvia of Mani (Figs. 22-23).

Evaluation of the state of conservation and pathologies Most common pathologies The greater part of Greek corbelled constructions are of dry-stone structure; their main â&#x20AC;&#x2DC;enemyâ&#x20AC;&#x2122; is Englouvi therefore unfavorable climatic conditions. Usually located at high altitudes and in inhospitable environments, they are exposed to humidity and vulnerable to frost; in winter, crystallized ice among the stones pushes the joints, and dry-stone masonries are therefore gradually dispersed. If abandoned or not regularly maintained, these edifices are threatened with rapid collapse. For the same reason, if built Fig. 10: Lefcada, Voltoi, site of the plateau of Englouvi with mortar, special care is taken for the protection of the domes from humidity with thick coverings of mortar. Evaluation of the state of conservation The vernacular corbelled architecture of Greece is nowadays almost totally abandoned. In Crete, only a few of the mitata remain in use, on the White Mountains and in the Rouvas Wood (Fig. 23). On the deserted plateau of

Fig. 10b: Aspect of a ruined voltos (Photo by Eleonora Fiorou)

LEFKADA

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Earthen Domes and Habitats Fig. 14: Plan and section of the Venetian watchtower (Skinias, East Crete)

Fig. 15a: Chalki and Alimnia Islands, types of kyphes, falsedomed (below) and terraced (above), after Moutsopoulos

Types of ground plan

Fig. 17: Corbelling dome forms in the Greek space. Types marked in grey color do not exist in Greece

Types of corbelling

Fig. 15b: the false-domed calyvi (Northeast Crete)

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Fig. 18: Natural disintegration of schists on the Mount Idi, Crete (foto: C. Chachlakis) Fig. 19: Mitato with external dry-stone ring (exofillo) in Rouvas wood, Mount Idi, Crete (photo by Cha-chlakis) Fig. 16: Nisyros island, group of beehive-domed Krefti and rectangular false-vaulted spiladi (plans by Vassiliades)

Nidha some mitata have begun to fall into ruin. The local authorities try to preserve them through restoration programs; however, only one or two masons remain who still have sufficient practical knowledge of these techniques. In the case of other small islands it seems that very little can be done. Only the voltoi of Lefkada remain partly in use, and this because the cultivation of lentils is maintained to a certain extent. Even so, the voltoi, as with all similar buildings, are in danger of damage through inappropriate repairs, due to the use of cement and other improper materials adopted by owners trying to adapt these primordial forms to the needs of contemporary life. Aesthetic and cultural merits Corbelled dome architecture constitutes a significant part of the Hellenic vernacular heritage, which has unfortunately not had the acknowledgement and concern it deserves. Its morphological and functional primitive-

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Earthen Domes and Habitats Fig. 20: A step of the analysis of the static function of cretan mitato, by Syrmakezis Fig. 21: The NE corner of the drakospito, mode of supporting of a circular dome by a square volume (drawing by Moutsopoulos)

Fig. 22: covering of a rectangular corbelled calyvi of Mani with macronia (stone beams) (drawing by Saitas)

ness places it in another age and the dramatic change in life conditions during the second half of the twentieth century has condemned such constructions to abandonment and extinction (Fig. 24). The Cretan mitata in particular can be counted among the most significant megalithic monuments in Europe. Their perfect static function and aesthetic merits are entirely due to the talents of brilliant, self-taught folk masters.

Earthen Domes and Habitats

List of References Arakadaki, M. 1999-2000, ‘Dry-stone constructions in Eastern Crete. ‘Calyvia’ in the province of North Mirabello’, Cretologica Grammata, vol. 15/16, pp. 249-286 (in Greek). Delighiannakis, M. 2003, The corbelled mitato in Crete: vernacular architecture and monument, Technical Chamber of Greece/ Section of West Crete, Rethimno (in Greek). Kouremenos, C. 1987, ‘Sarakatsanoi’, Greek Traditional Architecture, vol. 5, Melissa, Athens (in Greek). Fiorou, E. 2006, Englouvi, Lefcada, History of a Village. Women Priestesses of Land, the Lentils Feast and the Voltoi, Athens (in Greek). Moutsopoulos, C. 1958, Architectural monuments in the region of ancient Voura. History and morphology, Athens (in Greek). Moutsopoulos, N.C. 1975-77, ‘Karpathos. Historical, topographic and archaeological notes’, Scientific Annals of the School of Architecture, AUTH, vol. 7, pp. 39-744 (in Greek). Moutsopoulos, N.C. 1978-80, ‘The “Drakospita” of SW Euboea. Contribution to their architecture, typology and morphology’, Scientific Annals of the School of Architecture, AUTH, vol. 8, pp. 265-479 (in Greek). Moutsopoulos, N.C. 1989, ‘“Kyphes”; les maisons en encorbellement à caractère particulier, de Chalki au Dodecanèse’, Skopelos Symposium Proceedings “Space and History, Urban Architecture and Space”, Thessaloniki, pp. 157-167. Moutsopoulos, N.C. 2003, ‘Researches on circular constructions, from prehistoric straw huts to the Mycenaean tombs’, Proceedings of the International Convention on Vernacular Architecture of the Balkan Area (Veria, 12-15/10/2000), Thessaloniki, pp. 5-40 (in Greek). Petrakis, G. 1991, ‘The mitata of the plateau of Nidha on Psiloritis’, Taf, Journal of the Technical Chamber of Greece/ Section of East Crete, no. 1, pp. 15-19 (in Greek). Saitas, Y. 1987, ‘Mani’, Greek Traditional Architecture, vol. 5, Melissa, Athens (in Greek). Syrmakesis, C. 1988, The mitata of Crete. Researches on their static function with contemporary methods, Museum of Cretan Ethnology-Research Center, Voroi, Crete (in Greek). Vallianos, A. 2003, Traditional cheese making. The mitata of the central White Mountains, Benaki Museum-Photographic Archive, Athens (bilingual, Greek-English). Vassiliades, D.V. 1955, Introduction to the architecture of the Aegean space, Athens (in Greek). Vassiliades, D.V. 1966, ‘Rural edifices from Nisyros’, Laografia, vol. 24, pp. 343-361 (in Greek). Vassiliades, D.V. 1976, The Cretan Habitat, Hestia, Athens (in Greek). Warren, P. 1973, ‘The Mitata of Nidha and Early Minoan Tholos Tombs’, Archaeological Analecta of Athens, vol. 6, pp. 449-456. Zivas, D. 2003, ‘The ‘vardioles’ of Zakynthos’, Thesaurismata, vol. 33, pp. 303-310 (in Greek).

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Fig. 23: Siphakides mitato in Rouvas Wood, Idi Mountain, still in use (photo by Chachlakis) Fig. 24: Corbelled dome mitato in Rouvas Wood, Crete (photo by Chachlakis)

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Geographical and socio-economical context The use of temporary residences1 was very common in Sardinia (Fig. 1) due to the presence of compact built-up areas and the absence of rural dwellings in the countryside. Shepherds and farm workers used shelters or temporary residences, to various degrees of complexity as regards materials and techniques employed, and to various degrees of permanency considering duration and resistance through time, in order to defend their cultivated lands or livestock in places which were often some distance from the villages. A pinnetta was a transitional house used by agricultural labourers and grape growers while working in the countryside and was also convenient for shepherds during summer transhumances (Figs. 2-5). In cultivated areas away from villages it is possible to find clusters of farm-workersâ&#x20AC;&#x2122; pinnettas where each pinnetta has its own plot of land. On the other hand, shepherdsâ&#x20AC;&#x2122; pinnettas are more isolated, generally far from each other, since a breeder needs relatively large spaces for pasture.2 Climate and characteristics of transhumance in Sardinia In order to avoid the cold winters during the breeding period, which lasts from November to January, flocks were moved in winter down from the mountains, where the shepherd left his home and family, and brought to warmer areas on the plains or the seacoasts. In addition to those longrange displacements, the farm-worker effected summer shifts towards the mountain pastures, where the shepherds built the pinnettas to make cheese.

University of Florence, Italy

Shepherdsâ&#x20AC;&#x2122; pinnettas were lodging houses for several months, and so had to fulfil satisfactory services regarding performances as thermal comfort, fire resistance and durability. For these reasons choices of building materials were carefully made; generally stone and wood of the best quality were preferred, depending on their availability in the surrounding environment. Fig. 1: Corbelled domes distribution in Sardinia Distribution area Villages with presence of pinnettas Villages with high density of pinnettas Sassari MEILOGU Romana

Giave Illorai

PLANARGIA

Nuoro

MARGHINE

Samugheo Oristano

CAGLIARI The phenomenon concerns the whole island. Besides many local variations, the hut is called pinnetta in the north, barraca in the south. 2 The shepherd lives outdoors with his flock; from December to May he sells milk to industrial workers, so he does not need the pinnetta for cheese making, and for this reason pinnettas are only found in summer mountain pastures. 1

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Corbelled dome architecture in Sardinia

Silvia Onnis

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Fig. 2: Pinnatzu in a slope near Samugheo

Fig. 3: Pinnetta on a large limestone rock near Giave

Fig. 4: Pinnetta and dry-stone walls in Meilogu Fig. 5: Pinnettas near Giave

Origins and influences Essentially, scholars agree on the derivation of pinnettas from the nuragic hut.3 The nuragic dry-stone hut has a circular plan, with a thick wall resting directly upon the ground, with no foundations. Just draft polyhedral blocks were used outside, while regular courses were utilized inside, with the frequent use of wedges. Sometimes the hut plan becomes elliptical or irregular, in particular when it is joined with other huts. In some cases, traces of plaster have been found together with cork and the remains of rammed earth floors. Among the finds of those ancient settlements, we can identify some features which have been constant up to the present day in the diverse typologies of huts. Samples of nuragic hut have been found both with wooden coverings and straw, and also with tholos coverings. Constructive techniques have been handed down through the millennia and centuries by oral histories, together with the tradition of a seasonal housing model, which was adapted to the geographic and social context. There is also a hypothesis based on a Middle Eastern influence concerning habitat models and constructive techniques. This effect was produced by the arrival of the Byzantine monks who settled in Sardinia for the whole of the Byzantine age, before the 11th century (Sanna 2006). In the same areas involved in the diffusion of the tholos pinnettas (Meilogu), the remains of Byzantine churches could confirm this hypothesis. The churches were actually rural sanctuaries surrounded by small dwellings inhabited by believers and pilgrims during the days dedicated to the Saintâ&#x20AC;&#x2122;s celebration. The compound, named cumbessĂŹas or muristenes, was organized around a central space often closed by a portal. In some of those sites we can see remains of domes (Santa Maria di Saccu, Bolotana), in others toponomastic indications may be found (San Nicola di Trullas, Semestene). Organization and morphology of pastoral settlements In settlements characterized by tholos constructions, the morphology changes in relation to the typology and to the morphology of the site where the settlement rises. The pastoral settlement is the most complex and also the most constantly used among those installations distinguished by a pinnetta (domu â&#x20AC;&#x2DC;e bing3

Nuragic age: from 1800 to 238 bc (Romans landing in Sardinia).

Fig. 6: Rectangular tholos hut for sheeps close to the shepherd hut

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ia for the grape grower, hut for the farmer and for the breeder). Because of the needs of the cattle farm, the herder had to stay out of his village for long periods, lodging in areas rich in pasture. Herders’ temporary residences (named pinnettu/a – pinnatzu) were part of a cluster of structures, called su cuile, which was utilised during pastoral work (Fig. 6). The pinnetta was a residence for different people, accommodating the herder and the assistant herders, besides containing a workshop used for cheese production. The shepherd’s pinnetta always towers over the whole of the cuile and also over the surrounding territory. Around the pinnetta there is a complex of stockyards (Fig. 7), in the largest of these the shepherd milked the sheep or goats. Once the animals were milked, they were put into a second stockyard where the lambs, waiting in another smaller covered stockyard, could be then be nourished.4 The morphology of the rural settlement is simpler: the pinnetta is situated in a central position or behind a river, with a dry-stone wall enclosing the property. The site morphology conditions the functional organization of the settlement both rural and pastoral; animal shelters either contain shady trees and bushes or they are situated behind large surface rocks. Natural elements are utilized to create twilight and cool zones (su meriagu) and also to influence the microclimate of the cuile. The shepherd’s hut is protected against (Fig. 8) the wind by a right-angled wall (s’antanile) behind the entrance (s’enna o sa janna). The door is almost always orien4 Also the first stockyard is called cuile, the second one su passiali, the stockyards for lambs sos anniles (Le Lannou 1941).

tated eastward/south-eastward, in the opposite direction relative to the prevailing wind. Architectural morphological analysis The shape of the pinnetta is influenced by the materials available, which are worked according to the constructive knowledge handed down orally. For this reason, in spite of the presence of different typologies of temporary residences, every subregion is characterized by a model of huts (Fig. 14). ‘Su pinnatzu’ of Samugheo The Lithic hut (Fig. 12) is most wide-spread in Samugheo, having a circular plan, an almost vertical wall and a low cone-shaped testudo roof, and between these latter two elements there is a notable geometric separation. The trachyte tufa is available on site, found in natural slabs or workable pieces. This kind of tufa permits a regular construction and the result is a building with quite harmonious proportions. The pinnettas spread around the village are homogenous in size and form. The circular plan has an internal diameter of about 3 meters, and the wall is 0,80 meters thick. The internal height is 3 meters, while the height of the opening of the tholos, called boveda, coincides with the superior line of the lintel, that is 1,60 meter. Also in the countryside of the village, there are rectangular tholos and large circular stepped constructions. The ‘pinnetta’ of Meilogu The pinnettas (Fig. 11) are widely present in Meilogu: they are built with organogenic limestone which can be found in large areas of northern Sardinia. Here the typical pinnetta (Fig. 9) is characterized by a clear separation between the perfectly plumb wall and the skyward conical cover: the division between those two elements is marked by a line of flat protruding stones. The circular base has a diameter 3 meters long; from 1,20–1,80 meters height of erection and the tholos is built with slab stones. The height

Fig. 7: Drawing of a cuile, with dry-stone walls and the pinnetta

Fig. 8: Pinnetta of Giave with antanili Fig. 9: Typical pinnetta of the country of Giave. Fig. 10: Traditional Pinnetta between Planargia and Meilogu. Fig. 11: Traditional pinnetta of the country of Giave. Fig. 12: The most diffused type of pinnatzu of Samugheo. Fig 13: Ruined Pinnetta in Giave.

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Earthen Domes and Habitats Fig. 14: Different kinds of hut

changes according to the base diameter and the availability of certain stones but also in accordance with the function of the hut. The ‘pinnetta’ of Marghine and of Planargia In the subregions, basalt stones are present as “spheroidal rocks which are difficult both to work and to fit” (Baldacci 1952). The laws of drystone building and the final shape of this small building depend on the form and the size of the lithic material; the result is “a rough and heavy hut” (Baldacci 1952) which can also be appreciated for its unusual form, one could say, almost like a hedgehog rising from the earth (Fig. 10). That

effect is produced by the harmonious union between the wall and the covering. The base is made by a slightly scarped wall, its tapering becomes emphasized over the height of the door lintel that is in concomitance with the beginning of the tholos inside. A conical cover persists on this volume, in general it is very low and is made up of a mantle of flat stones or by a vegetation covering. Materials The tholos pinnettas occur in those lands that offer slab stones5 such as 5

The slab stone is called pedra lada in the north, teggia o tella in the south

sandstone, tufa, limestone and granite (Giotta & Piccitto 2006). However there are samples of tholos huts also in lands rich in basalt stones. This stone is utilised in large rocks6, without any working into slabs. In Samugheo7 trachyte tufa was used because of its good workability (Baldacci 1952): the wall was built with the stones found in the surroundings, without any working on their diverse forms and sizes. The dome, on the other hand, was built with the finest and flattest stones, i.e., slabs (Figs. 15-16) (loc. Teggia) found in the countryside or obtained by cutting bigger stones with the help of iron wedges (Cozzas) and slaphammers.

The pinnettas Orosai and Marta Maria in Birori (Marghine) prove that smaller slabs are not necessary to build dry-stone. Interview with Antonio Loi (class 1926), 12 gennaio 2009 , Samugheo. When he was young, the interviewed took part in the building process of many pinnaztos in his village.

Earthen Domes and Habitats

Analysis of building techniques in Samugheo The building of the Samugheo (Fig. 15) pinnatzos started with what is defined as â&#x20AC;&#x2DC;assisted self-buildâ&#x20AC;&#x2122; today. After having removed the rocks and stones, the landowner and his whole family enlisted the help of the builders of pinnatzos. Usually the builders worked in twos: one arranged the stones of the tholos, the other checked the correct disposition of the stones with particular attention to the overhangs. The first step of the building plan was to draw the perimeter of the construction by means of a string which was fixed by a nail or a picket embedded in the ground. This was a rudimentary compass by which a circle was drawn (usually with a diameter of 3 meters) on a clean area, though the presence of surfacing rocks could work as an advantage because of the absence of foundations. The builder arranged the first row composed of stones with an equal or greater thickness relative to the wall; over this first row, another one was put in lengthways (a sorelle) with regard to the prevention of water infiltration. Over the second row, the real walls were built with two distinguishable decorations (one internal, the other one external) not linked by cross blocks, fixed instead by an alternating use of stones of different length. At a length of 140-160 cm, above or on the same level of the extrados of the lintel, the internal decoration was interrupted and the stones of the tholos began to overhang, while on the outside the wall was still vertical or just tapered up to certain height (215-240 cm). Here the stones acted as a support to give balance to the building, well-fixed, however, by the

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Fig 15: Building detail of a typical Pinnatzu of Samugheo. Fig 16: Detail of Ruined Pinnetta in Giave.

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C첫bburo, corbelled domes of the Nebrodi Mountains (Sicily)

Earthen Domes and Habitats

The c첫bburo is a small tholos building which spread to Sicily and in particular to the area of the Nebrodi Mountains. The cubburi, called also casotti, or cubo and cuba (Arabic origin words), were built in areas formerly devoted to grazing and were used as shelters by shepherds. They are particularly diffused in the villages of Montalbano Elicona (Monte Castellazzo), San Piero Patti (Contrada Taffuri), Raccuja, Floresta, Roccella Valdemone, Tripi (Pantano 1994). The c첫bburo, already built in the megalithic age, was being built and used up until the early years of the twentieth century. The c첫bburo is architecturally reminiscent of the nuraghes and pinnettas of Sardinia or the trulli of Puglia, and was built with the same purpose of the caciare in Marche and Abruzzo or the dammusi in southeastern Sicily. Generally they are built near dry-stone walls or natural shelters, on gentle slopes, not requiring the use of mortar. The architectural structure is circular. Starting from the base, the stone blocks are arranged in a concentric manner, so that each row supports the upper. The construction ends with a hemispheric corbelled dome, which took a spiral form during the period of the Arab domination. The entrance, consisting of a trilithic structure, is generally open on the outside and, in some cases, is low and narrow. The buildings are variable in height: the first were small, but over time were built larger to become residential shelters. We can observe that over the centuries, the buildings remained very similar to the initial structures. List of References Pantano, G. M. (1994), Megaliti di Sicilia, Edizioni Fotocolor Cubburo, http://it.wikipedia.org/w/index.php?title=Cubburo&oldid=20357032 (2 May 2009).

Fig. 1: Cubburo in Montalbano Elicona (Photo by Ivan Alicata) Fig. 3: A double Cubburo in Montalbano Elicona (Photo by Ivan Alicata)

Fig. 2: Cross-section of two types of cubburi. Redrawn from the original picture of Filippo Accordino at it.wikipedia

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stones of the tholos, the longest available. The closure was composed of one or two slabs on which a large round pinnacle was placed to hold down the closing slab. Some small thin slabs were put on the frame of the tholos as a covering to keep out rainwater. Most of the ancient buildings have only one opening, whereas the recent constructions have two opposite doors, perhaps to encourage draughts and to improve ventilation. The entrance, slightly splayed towards the exterior, characterizes all lithic huts in Sardinia (Sanna 2006). The floors were all made with paving slabs, apart from a little central square area surrounded by standing slabs, this being the room with a fireplace. Sometimes the internal part of the wall was plastered with clay up to the beginning of the tholos, a protection against the wind, whilst allowing smoke to escape through the stones of the tholos.

Conclusions: Aesthetic and cultural qualities The pinnettas and their respective dry walls are buildings of great simplicity with no marked and no formal qualities. They are well-integrated and characterize the rural and pastoral landscape of Sardinia, an attestation of a nomadic culture that has been present in the region for millennia. At present, for the first time, the Region of Sardinia is trying to include rustic residences in the plan to safeguard Sardiniaâ&#x20AC;&#x2122;s monumental heritage. The aim is to make the best of this territory and to attract a particular kind of tourism interested in rural and pastoral culture. The recovery could possibly lead to the establishment of the presence of able workers on this island, which would also promote the passing on of knowledge from the elder, holders of ancient learning, to younger workers.8*

Evaluation of the state of conservation and pathologies The pinnetta does not need ordinary maintenance; it can be damaged by lighting or by animal action on the roof, for example by goats that can alter the disposition of the stones causing infiltration of water. If it is abandoned for long periods, it can also be damaged by wind-sown plants growing in deposits of earth among the stones. In those cases the owner would carry out maintenance directly, mounting the roof with a rudimental ladder created from a tree trunk using the fragments of branches as rungs.

8 * Credits: For the information provided: Antonio Loi, Roberto Marongiu. Drawings and photos by Silvia Onnis.

List of References Angioni, G. & Sanna, A. 1988, Sardegna, Laterza, Rome. Baldacci, O. 1952, La casa rurale in Sardegna, Centro di Studi per la Geografia Etnologica, Florence. Chessa, S. 2008, Le dimore rurali in Sardegna, con particolare riferimento al Monteacuto, al Goceano, al Meilogu e alla Gallura, Documenta, Cargeghe. Giotta, C. & Piccitto, M. 2006, Pinnettos. Antichi ovili della Sardegna, PTM Editrice, Mogoro. Le Lannou, M. 1941(rist. 2006), Pastori e contadini di Sardegna, Della Torre Editions, Cagliari. Sanna, M. 2006, Trulli e Nuraghi della Sardegna, PTM Editrice, Mogoro.

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Ogival shape and basalt stone Pinnetta in the Marghine.

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Geographical, economical, climatical and geological context Dry-stone corbelled dome constructions of major importance are present all around the Apulia region (southern Italy), showing different features and shapes in close rapport with the diverse characteristics of local building materials and with the production and environmental context (Fig. 1). The generic name for this type of construction is “trullo”, which refers to the most common type in the Itria Valley, while in the rest of the region the corbelled dome buildings have a variety of local names: Pagliariu, Capanna, casedda, pajaru, trullo, furniedoi, pajara, chipuro, specchia. The hinterland of Apulia is composed of three distinct plateaus, not exceeding 700 meters above sea level, called Murge: northern Murgia, the Murgia of Trulli and the Murgia south Salentine. The subsoil is mainly made up of a permeable limestone. The hinterland limestone layer, in the slopes towards the coastal plains to the south, is surrounded by a strip of “tuff”, a homogeneous sedimentation of volcanic fragments and marine shells, very friable and similar to sand conglomerate. The construction of rural landscapes in dry stone originates from the necessity to rid the land of rocks for the planting of crops. The stones were piled up randomly at the sides of the fields to be then used as fencing, shelter and construction owing to the ease in cutting this type of rock. The small stone walls called pareti, a common sight in the Apulian area, are not only stone hedges to divide and demarcate the boundaries of the property, they also serve to retain the land and protect it from wind. The dry-stone construction, with its considerable thickness and limited openings, is the type of construction more suited to the climate of the Apulian countryside, with its very hot summers and relatively harsh winters.

University of Florence, Italy

Origins and influences The origins of the tholos construction in Apulia go back to the protohistoric period, according to researchers, the form of the trullo originally having been used for tombs and fortifications and later for domestic applications. The word trullo is assumed to come from the late Greek τρουλλος, meaning dome, or from the Greek-Byzantine term torullos, which indicated the domed hall of the Imperial Palace in Constantinople. Fig. 1: General distribution of corbelling dome

Foggia

Barletta-Andria-Trani BARI

Taranto

Brindisi Lecce

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Corbelled domes of Apulia (Italy)

Letizia Dipasquale Natalia Jorquera Silva

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Earthen Domes and Habitats Fig. 2: Landscape in Itria Valley

Despite archaeological finds from prehistoric times, and foundations of stone huts dating to the Bronze Age found in the development areas of the trulli, no trulli of ancient date have been found; in most cases it was easier and safer to demolish and rebuild rather than repair. However, looking at maps and notary documents dating back to the 16th-17th century, there is a considerable presence of dry-stone constructions spread across the territory. In the Itria Valley, dry-stone construction has a particular history: between the 16th and 17th century, following an order by the Count of Covers John Acquaviva of Aragon, owner of the manor, the entire village of Alberobello was made with dry-stone corbelled dome constructions. When the edict â&#x20AC;&#x153;Pragmatic of Baronibusâ&#x20AC;?, imposed by the Bourbon court of the of Naples, introduced a charge on all new towns and buildings, the count forced his subjects to use dry stones without mortar for building their homes, and so in case of direct inspection, it was possible to disassemble the stones quickly, spread them around on the ground and then rebuild them later. In 1797, when the dominion of the Counts of Conversano ceased, the use of mortar was reintroduced, but the trullo typology remained rooted in local construction culture.

Urban morphology analysis In most of Apulia, buildings in dry stone are part of a complementary rural architecture to houses in villages, used as a daytime shelter for farmers, storage for agricultural tools, or accommodation during harvest. Only in the Itria Valley are the trulli buildings permanently inhabited. In rural areas, dry-stone buildings are isolated, with a main body to which one or two smaller units are sometimes attached (Figs. 3-4); they are at the center of the primary unit or on the border area to leave greater room for crops. Surrounding the building is frequently a farmyard, a storage tank, and sometimes an enclosure for animals beside the entrance and a container for pressing grapes. In the Itria Valley rural housing has a more complex and advanced character: from the isolated unicellular trullo (Fig. 5) to the complex consisting of multiple cells. The aggregation of one or more trulli of various sizes forms a dwelling. A greater number of trulli grouped together form the masseria trullaia or set of buildings with small courtyards, farmyard, spaces for animals, small fenced gardens and orchards (Fig. 6). Buildings for residence are normally accompanied by other trulli designated for palmento (an area for the processing of grapes with a collection tank below the floor), ovens, stables and storerooms for straw. These latter are recognizable by the removable plate for the input of straw and fodder into the vault, and the presence of stone stairs in the outer wall for access to the top.

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Fig. 3: Furneddu near Martano (Lecce)

Fig. 4: Furneddu near Collepasso, (Lecce)

Fig. 9: Trullaia near Cisternino

Fig. 5: Isolated trullo with alcova Fig. 6: Trullaia near Alberobello (Bari)

Fig. 7: Group of trulli in Aia Piccola district, Alberobello Fig. 10: District of Rione Monti, Alberobello Fig. 11: Aia Piccola, Alberobello

Earthen Domes and Habitats

Fig. 8: Corbelled domes near Martano (Lecce)

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Fig. 12: Primitive dome with ogival profile, simple or with steps Casedda near Canosa (Barletta-Andria-Trani)

Casedda near Polignano a mare (Bari)

Fig. 13: Dome with truncated cone profile, simple or with steps Furneddu near Calimera (Lecce)

Pajara near Racale (Lecce)

Fig. 14: Dome with truncated pyramid profile, simple or with steps Furneddu near Melendugno (Lecce)

Furneddu near Calimera (Lecce)

Fig. 15: Composite dome with circular base and conical cover, simple, or with a protruding base Trullo in Alberobello (Bari)

Trullo near Locorotondo (Bari)

Fig. 16: Composite dome with quadrangular base and conical cover, simple, or with a protruding base Trullo in Alberobello (Bari)

Trullo near Locorotondo (Bari)

Fig. 17: Complex trullo composed of a central volume with smaller added rooms Body of trulli near Locorotondo (Bari)

Body of trulli in Alberobello (Bari)

Architectural morphology analysis In Apulia we can see a wide variety of dry-stone domed building, distinguishable in two parts: the internal structure consisting of the base wall and the dome, and the wall structure of skin render, of which the architectural shape varies from area to area reflecting the characteristics of the stone material, inspiration of the manufacturer and local building traditions. According to the external shape of the dome structure, they can be classified as: - Primitive dome with ogival profile, simple or with steps (Fig. 12) - Dome with truncated cone profile, simple or with steps (Fig. 13) - Dome with truncated pyramid profile, simple or with steps (Fig. 14) - Composite dome with circular base and conical cover, simple, or with a protruding base (Fig. 15) - Composite dome with quadrangular base and conical cover, simple, or with a protruding base (Fig. 16). While the first three types are more or less widespread in all rural areas, the last two are present only in the Itria Valley. Each type presents many variations in size, number of steps, presence and shape of the outer stairs, shape of the internal plan (circular, pseudocircular, quadrangular), and shape of the base profile (circular, oval, quadrangular with rounded corners or square corners). The primitive dome is the simplest, usually with an ogival profile, and

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Alberobello This form of architecture reaches its highest expression in the urban area of Alberobello, where the districts of Rioni Monti and Rione Aja Piccola comprise exclusively of trulli. In the grouping of individual cells we can generally identify three possible types of aggregation: the housing unit developed parallel to the road (Fig. 7), orthogonally, or in both directions. The Rione Monti district of Alberobello (Fig. 10), separated from the rest of the village, is the largest settlement of the city of trulli (1,030 trulli); built on a considerable slope, it opens fan-like towards the hill and extends for 15 hectares . The Rione Aja Piccola district (Fig. 11), with its 590 buildings, is the second largest settlement of trulli. Its houses converge towards a common farmyard, where up until the end of the feudal age farmers were required to thresh grain publicly.

Foggia

Barletta-Andria-Trani 3

BARI 4 Taranto

Brindisi

Lecce 5

Fig. 18: Distribution areas of dry stone corbelled domes in Apulia: 1. Gargano and Tavoliere zone, 2. Zone on the left bank of the lower course of the Ofanto River, 3. Coastal plain around and north of Bari, 4. Itria Valley, 5. Peninsula Salentina

serves as a shelter: the walls are thick and low, with a circular plan without openings, except for a small and very low entrance with a trilithic arch. Over time the shape of the ground plan, both internal and external, evolved toward the square base to improve internal use, streamlining the space and the area-volume ratio. The entrance is generally oriented towards the southeast, to protect from cold winter winds coming from the north. Inside the rural buildings the only furniture elements are niches cut into the wall to store objects. Only a few homes were equipped with a bed made of stones or wooden boards over the straw, threshed barley or worn garments. In the Itria Valley we can see the evolution from the rural type to a newer, less rustic type and one more suitable to permanent housing: to the central core of an almost square shape smaller rooms are added, the alcove and the small trulli that generally contain the niches for beds and fireplaces, connected to the main trullo by semicircular or segmental arches (Fig. 17). Dry-stone rural architecture in Apulia is concentrated in the following areas (Fig. 18).

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Hight density Medium density Low density

Fig. 19: Distribution of corbelling dome constructions in the Itria Valley

3 2 1

Fig. 20: Organization of spaces in a trullo: 1. Main room; 2. Kitchen with fireplace; 3. Alcove

Fig. 21: Casedde in Pietragea, near Polignano a mare, (Bari)

Gargano and Tavoliere zone (comprising the municipalities of Manfredonia and San Severo, Ischitella, Sannicandro Garganico and San Marco in Lamis). Local name: Pagliariu. Dome construction is related to agricultural and pastoral activities, and to the construction of containment walls in dry stone for terracing the hills. The form is generally of truncated cone, and in some cases tiers, covered with clods of earth. Zone on the left bank of the lower course of the Ofanto River (comprising the municipalities of Cerignola, Trinatapoli, San Ferdinando di Puglia). Local name: Capanna. The presence of capanne in dry stone in this area comes from the seasonal migration of farmers from the north of Bari (for occasional or seasonal work such as plowing, sowing, harvesting of olives and almonds) and shepherds from Abruzzo (for animal shelters and places for the collecting, elaborating, processing of products related to sheep farming). The capanne are simple, with an internal circular or quadrangular perimeter and an exterior that is generally circular. The most common forms of the outer profile are: ogival, tiers, truncated cone, or more rarely truncated pyramid. The stone used is crusta, a local limestone formation, while the door and window have jambs and arch (almost always semicircular) in tuff. The stone, non-compact and of a heterogeneous composition and structure, is not easy to work and is more often used in small blocks. The capanne still existent are few, while in 1954-57 hundreds of capanne were recorded in topographic mapping: the replacement of olive cultivation with vines and peach trees has profoundly altered the landscape, destroying most of the rural structures.

binder. The outside shape of the trullo has evolved from lower forms of circular plan with thick walls. In recent examples where the spaces are contained in rectangular form, the cones are set to greater height, with a flat facade to the main front where the entrance and two windows open symmetrically. In the trullo, the smaller spaces, the separated domes, or the alcove separated with an arch, are organized around a large central area with an open entrance (Fig. 20). The area of the fireplace and the kitchen has openings on several sides for a more effective diffusion of heat and often it has a corner in the room for a bed. In the largest dome, we can find an intermediate floor, made with planking laid over two or three beams set between the stones of the cone at the level of the vault, which is accessed through a trapdoor and wooden ladder. This environment (orije, from Latin horreum: granary or warehouse) was used to store dried food products, grains, flour and other foodstuffs for household use. Wooden beams, placed horizontally at the top and still visible in some trulli, had the function of hanging food, supplies, kitchenware and tools in order to keep them well raised off the ground. Inside the trullo are also overhang shelves and niches for storage of goods and furnishings. In the trulli made from the 18th century onwards, the interior walls, the exterior bearing wall and the upper parts of the roof near the pinnacles, are plastered. The entrances of the oldest trulli are characterized by a stone lintel and discharge arch which reaches the height of the eave line of the cone. This architectural solution has evolved up to the semicircular arch surmounted by a triangular tympanum. The windows in the trulli are quadrangular in form and very small, mostly located below the gutter line. In some cases, the window is a little protuberant from the coverage, in others, the window is set directly into the dome to air the space above the central compartment. In some trulli, flat jutting stones called cianche are arranged neatly on the exterior walls as decorative elements and shelves to support objects. Disposal and collection of rainwater from roofing occurs through channels made with concave slabs of limestone along the intersecting lines of the domes.

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Coastal plain around and north of Bari (comprising the municipalities of Molfetta, Terlizzi, Bitonto, Ruvo di Puglia, Rutigliano, Mola di Bari, Polignano a Mare). Local name: casedda, pajaru. The territory of the south of Bari on the coast and north to the hinterland is very rich in dry-stone constructions. In some areas there are primitive domes with ogival profiles, quadrangular bases and domes with a double wall unit, without abutments. The domes are small in dimension, especially the internal cell, often on a square plan. External stairs are rare, more common is the use of protruding stones set into the dome for inspection and maintenance access to the upper parts. The construction of the Pietragea zone, on the coast near Polignano a Mare (Fig. 21) is a special case: dry-stone buildings with ogival dome or truncated pyramid, the remains of peasant settlements erected at the end of the nineteenth century and now abandoned, are widespread on the plain facing the sea, creating a rather special landscape. In the domed buildings in the northern area of Bari, due to the porosity of the limestone used, horizontal surfaces are coated with lime plaster. Itria Valley (comprising the towns of Alberobello, Locorotondo, Costernino, Putigliano, Noci, Castellana, Martina Franca, Ceglie Massapica) (Fig. 19). Local name: trullo. In the Itria Valley domed buildings have become permanent homes by modifying the shape and structure of rural buildings, preserving the building technique and the covering dome in dry stone. In the trullo we can identify three basic components: the wall base, the false inner dome, and the coating coverage, all made of limestone without

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Earthen Domes and Habitats Fig. 22: Furneddo near Martano (Lecce) Fig. 23: Furneddi in Salento 0 1 2 3m

Peninsula Salentina (in the Salento area, comprising the municipalities of Martano, Maglie, Melendugno, Gallipoli, Racale, Salve, Ugento, Pat첫, Castrignano del Capo Leuca and Corsano). Local name: furniedoi, pajara, chipuro, specchia. The agrarian landscape of Salento, characterized mainly by olive trees, is full of dry stone constructions with an extraordinary variety of shapes and sizes. The most widespread architectural form is the truncated cone or truncated pyramid (Figs. 22-24), arranged singly or in twos, and we can find them with greater concentration in the area to the southeast and north of the peninsula close to Martano. Towards the southwest of the peninsula the presence of other structures with steps is frequent, where the outer part is formed by overlapping sections of the pyramid or cone decreasing

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Fig. 24: Furneddo near Racale (Lecce)

in width and height, and the number of steps can vary from one to three. The internal perimeter may be circular or quadrangular, with dimensions ranging from 2.5 to 6 meters approximately. The height of the domes (3 to 10-15 meters in the most exceptional cases) not only varies according to the diameter, but also to the size of the stones available. Longer stones allow a larger overhang of the rings, thus allowing faster closing of the coverage, on the contrary, where the rock is smaller, the reduction of the diameter of the dome is solved with a larger number of rings, so the building is raised considerably and it becomes necessary to reinforce the outside through one or more steps of abutment. The corbelled dome was completed by a large slab over the ring, removable if necessary, to aerate the room or to put the straw or cereal into the building when used as a deposit.

Inside we can find niches cut into the wall to store items and often as a fireplace in the corner, called camino di fuoco. The floor is generally of hard clay, rarely of stone slabs. Outside we can see stairs often shaped into the outer layer of stone, to allow the cleaning of the surface of the conical dome, to facilitate original construction, for maintenance purposes and to access the cover where figs, peppers and other foods are placed to dry. In the step constructions, the opening of the door is often preceded by a sort of vestibule cut into the wall of abutment (Costantini, 1988). The cover has a â&#x20AC;&#x2DC;roundedâ&#x20AC;&#x2122; form, in some cases it is almost flat for use as a farm area for the processing of agricultural products.

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Limestone or dolomitic rock Sandstone Gravel and conglomerate rocks Marlstone Incoherent deposits with sandy components. Alternate rocks Leccese stone (local sandstone) Fig. 25: Geological map of Pulia

Analysis of materials and constructive techniques Materials The spread and characteristics of dry-stone buildings is determined by geomorphological characteristics (Fig. 25) that generate this type of architecture in various, often original configurations and structures. The development of dry-stone domes in Apulia is linked to the abundance of limestone (Fig. 30); its physical characteristics such as workability, high compressive strength, low coefficient of thermal expansion and low freezing, make it particularly suitable as a construction material. The equipment used for cutting and sketching out the stone is quite basic, it often consists just of hammers (martellina), one or two serrated tips (martidde), and chisels (stambe). Where the stones are present in the form of small and unformed pinning stones, it is frequent to use a mortar of lime and earth, to mason the stone and as a plaster inside the building. Where present, an easily workable sandstone (tufo) is used for the jambs and lintels of the openings.

Building techniques The constructive process of dome building is constant with few variations, as determined by the size of the stones available (Fig. 28). Once the site has been chosen, the farmer or the master builder, draws the plan of the shelter directly on the ground. If the rock is outcropping, it is leveled properly to create the ground plane and the floor, otherwise the layer of soil covering the limestone layer is removed, and the wall of the block is built, consisting of two parallel rows of large stones, which will support the others. The technique is that of the double wall. The wall is tissued by laying the individual stones so that the flat side forms the level, taking care to offset the joints and to fill gaps with slivers of stone. The space between the two walls, filled with small irregular stones, has a variable thickness depending on the size of stones available for the external wall. In some buildings the foundation becomes a wider, more solid base, 40 cm high, which is both a seat near the entrance and a stair at the side of the building. The outer walls are constructed up to height of about 1.5 to 2 meters with the help of a guide consisting of two taught strings. The section of the wall, of considerable thickness that goes from 150 to 180 cm, has a trapezoidal shape. The internal wall, with some exceptions, is always vertical. The pieces of stones are arranged more or less aligned according to the regularity of form, in some cases they are arranged in a tilted way depending on the installation. There are some cases where interior walls are painted with lime and some parts are plastered with mortar of lime and earth. At a height ranging from 1 to 1.8 meters, the transition from the square plan to the circular base of the dome begins, through a change in form of the masonry set at the corners, which takes on a circular form course after course. Often in the corners four protruding stones act as a support to start a sort of â&#x20AC;&#x153;pendingâ&#x20AC;?. The stones (coperte), are placed one next to the other, taking care in closing the most evident cracks with chips and flakes of stone. The roughness and weight combined with the pressure generated from inclusion of the flakes into the joints, prevent the sliding or overturning of stones. The last link in the vault is closed with a large plate (chianca) often decorated with a cross. The corbelled dome that forms the internal structure of the cover, is completed by an outer shell which constitutes an abutment to the dome and has a form dependent on the type of construction; between the two layers

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Fig. 26: Inner view of the dome in a furneddu Fig. 28: Constructive section of a furneddu in Salento

Fig. 30: (a-e). Different types of limestone.

Fig. 27: Inner view of the dome in a trullo Fig. 29: Constructive section of a trullo

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Earthen Domes and Habitats Fig. 31(a-e): Details of a rural corbelled dome; fig 31a. Door with semi-circular arch; Fig 31b. Door with semi-lintel of two monolithic blocks; fig 31c. Cianca,arranged on the exterior walls as decorative elements and shelves to support objects; fig 31d. Roof , fig 31e. Stairs

nails. The shutter rotates around a vertical stick set between two stones, the upper the lower bore being excavated.

Fig. 32: Different tipes of lintels Fig. 33(a-e): Details of a trullo; fig 33a: Door, fig. 33b. Eaves; fig. 33c: Opening; fig.33d: Section of the vault: fig 33e: View of a semicollapsed dome

some smaller stones are placed as filling. The internal dome and outer shell are erected simultaneously, according to horizontal planes, starting from the implementation of the internal rings. To determine the radius of the rows of stones set in a ring, the manufacturer uses a rope on a stick fixed at the center of the ground plan of the dome (Ambrosi, 1997). When there are external stairs, they follow a spiral form, the development of the dome, and/or are embedded into the wall structure by reducing the thickness of the walls of containment, or they are formed by larger embedded stones that form lagged stairs. The outer shell of the building is made up of flat stones placed carefully in concentric rings to waterproof and stabilize the whole. The extrados of the summit is usually covered with clods of earth, though in many cases it is paved with mortar consisting of a mixture of clay, lime and brick fragments. Openings in relation to the rocks available range from the primitive trilithic, to the lintel of two monolithic blocks, and to the semi-circular arch, sometimes surmounted by a triangular niche to reduce the upper loads (Fig. 32). The fixture is usually made of olive wood planks fixed together with wooden

Building technique of trulli The constructive process of the Itria Valley trulli is slightly different: the trullo is composed of two distinct elements, for both the form and the stone used: the base and the vault (Fig. 29). The construction of the trulli was originally performed by the inhabitants, and only after the time was it given over to skilled workers called â&#x20AC;&#x153;trullariâ&#x20AC;?. The first operation consists of removing the ground to the bedrock substrate, and proceeding to cut the rock into pieces up to a depth of 80-90 cm. The best stones are set aside for construction, others are scattered on the rock layer, taking care to put the smaller pieces on the bottom and the larger pieces on top. A layer of red earth taken from the vicinity (bolo) is spread on the layer of broken limestone. If the trullo is being equipped with a collection tank, it is carved and finished with a barrel vault or with a dome made of stone and mortar, which in many cases serves as a support for the floor of the upper construction. The rocks are separated according to size: the larger sizes are used to construct the edges of the base or the lintels of doors and windows, and those of medium size for the walls and vaults; slabs of medium thickness are used for floors, thin plates (chianche) and as a coating for roofs. The construction of the trullo starts with the walls of the base (muredda),

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which rise above the altitude of the floor for about 2 meters, with a thickness that varies from 1-1.5 meters up to 2-2.5 meters. The technique is still that of the double wall with the vertical internal wall plumb and the external tilted. The space between the two walls is filled with rubble and waste. During the construction of the wall, the possible windows and the niches with vaults are cut into the thickness. The small openings for windows are generally surmounted by a stone lintel and the door is made with a double lintel, made partly of stone and partly of wood, and often complemented by an overlying semicircular discharge arch. The fixtures are generally made in oak wood with double thickness, with an independent smaller opening and stone hinges. Once the desired height is reached, the vertical wall is leveled to start the construction of the conical structure of the trullo. Stones arranged obliquely are placed at the corners of the openings and the masonry set of the wall is progressively altered at the edges until a circular horizontal section is reached. From this point the corbelled dome is raised, obtained by overlapping layers of horizontal rings. Each ring is made up of carefully chosen stone blocks, similar in each course in form and size, arranged in concentric circles decreasing upwards to close the last ring with a large flat stone (chianca or serraglia); the stone blocks are specially cut, with the face oblique and the setting plan turned inwards. Each stone is settled in order to fix it between the two side ones, slightly overhanging in relation to the underlying ring; the stones of the same layer are in lateral tension with each other, forming an almost rigid annular system. The tendency of the elements of the corbelled structures to topple in-

wards is contrasted by the internal stresses of the arches that compose each horizontal ring, and by friction between the different rings. The roundness of the dome is achieved with no methods or tools, but only by visual control and the skills of the craftsman. Once the internal structure is completed, the creation of the outer shell layer is carried out with limestone slabs (chiancarelle), presenting fracture plans easily leafed in slabs from 5 to 7 cm thick, eventually taking on a dark gray uniform patina due to surface alteration. The chianchiarelle are inclined towards the outside and placed with joints staggered over the underlying stone blocks, in order to facilitate the outflow of water. In the meantime the ring of chianchiarelle is completed and the intermediate space is filled with small stones, in that way the dome is composed of three distinct layers. The cavity is an air chamber that acts as isolation to the interior. The stones of the base of the cover are connected to create a gutter for water runoff. The last stone of the compluvium, is modeled “a canala “, possibly serving to convey water into the tank below the house. A similar profile completes the steps on the ground. The apex of the dome is surmounted by the spire, an architectural element in limestone covered with lime without specific function, which was used to satisfy the aesthetic and spiritual needs of the owner-builder. In the same way, the symbols painted on the outside face of the vault, introduced only in more recent years, do not have a function or specific meaning, related instead to the spiritual leanings of the occupants, or are mere decoration. The courtyard in front of the trullo is paved with “chianche”, stones of a thick-

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The caciare have a structure similar to the trulli of Apulia. Transhumance over the centuries has created a close relationship between the shepherds of the central Apennines and of the Tavoliere in Apulia. The circular caciara vault is a corbelled dome. List of References Micati, E. 2001, Pietre d’Abruzzo. Guida alle capanne e ai complessi pastorali in pietra a secco, Pescara, Carsa Edizioni, Collana “Gli Scrigni”; Cappelli, C. 2007, Le caciare, capanne di pietra con copertura a tholos della montagna dei Fiori (Ascoli Piceno), Ascoli Piceno, Lamusa, 2007, collana «I Galletti», ISBN: 8888972218 Caciara, http://it.wikipedia.org/w/index.php?title=Caciara&olid=22283116 (2 May 2009).

Fig. 1: The caciara, typical dry-stone hut, in Montagna dei Fiori during winter. Photo by Alessandro De Ruvo Fig. 2: The caciara in Montagna dei Fiori. Photo by Alessandro De Ruvo

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Caciara of Montagna dei Fiori (Abruzzi, Italy) The caciara is a dry-stone hut built and used by the shepherds of the Apennines in Central Italy. Commonly known as a Tholos hut, in Abruzzi and Marche it is called a caciara (Micati 2001). The structure is built of stone without the use of mortar. The shape of the corbelled dome is semi-spheric or ogival. The technique allowed shepherds to build them without the use of complex equipment or wooden ribs. The caciare were used by shepherds for personal shelter and for the manufacture and storage of cheese. The term derives from caciara which means precisely a place to make and store cheese. The caciare are present on the Gemelli Mountains, and particularly on the Montagna dei Fiori (Mountain of Flowers) to the north-east of the Monti della Laga on the border between the provinces of Teramo and Ascoli Piceno (Cappelli 2007). Over 50 huts are still visible and some of them are in a good state of preservation.

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ness from 10 to 30 cm, of the same width but variable length, which rest on a layer of gravel. The interior walls are in some cases plastered with lime mortar and earth, and usually bleached with lime, in order to reflect the light that penetrates through the shaft of the door and small windows, and for better hygiene. The painting is a job entrusted to the women, and it is generally performed before local festivals or other celebrations. Evaluation of the state of conservation of architectural heritage In the last few decades, also in Apulia a transformation of the rural economy and agriculture has occurred to radically and irreversibly alter the countryside. Structures in dry stone were developed with an important contribution by self- construction and today prove expensive considering the labor costs (labor-intensive technique), and so they have been replaced by buildings in masonry and reinforced concrete, abandoned to decay or modified by interventions or tampering incompatible with the original structure. The stone structures, while having a high resistance to external factors, if ignored may quickly undergo degradation processes that slowly lead to the collapse of the whole structure. Infiltration of water, attacks by vegetation and other external factors determine the flow of one or more elements and hence the static imbalance of the dome. The outer layer is the first to be affected: sliding of the external elements does not directly determine an internal collapse of the dome, as they are two structurally separate entities, but does make it more unstable and vulnerable to factors of degradation. In the northern region, lack of maintenance is also linked to the shortage of limestone: the recent installation of new vineyards and tree crops, which have replaced olive trees, has tampered with the surface layers of soil, and there is also the removal of the layer of stone to access the sand below. The case of the Itria Valley trulli is an exception: the level of conservation is satisfactory despite the discomfort of the inhabitants living in homes with small openings. The power of the urban settlement of Rioni Monti and Aja Piccola districts, the stability of the local building tradition and the relative cultural isolation of the area, have allowed the integral preservation of the old town over the centuries. To emphasize the importance and the value of these buildings, in December 1996, UNESCO approved the registration of the trulli of the Itria Valley on the World Heritage List.

Since 1930, punitive regulations have been applied to prevent uncontrolled and rapid transformations of this architectural heritage. In 1976, the Region of Apulia under a regional law provided public assistance for the recovery and restoration of the trulli. Since this, many small steps were made to establish a more decisive and detailed intervention that has led to a series of policy documents for the restoration of the trulli. The current technical standards on new measures stipulate the maintenance of materials and traditional building techniques, allowing changes of use and the addition of new buildings only if they are compatible with the original and maintain identity. Despite the rules, the materials and some construction methods risk being changed: the limestone blocks are often replaced with those of tuff, being faster to prepare, and instead of the mantle of coverage with the hand-split chianchiarelle limestone slabs, pre-cut plates of the same thickness are preferred. The objective of conservation of cultural and architectural heritage such as the dry-stone constructions of Apulia, and the Itria Valley in particular, may be achieved not by taxation and regulations, but with an integrated system of knowledge schemes, information, incentives and behavior patterns, in order to keep alive and perpetuate not only the forms, the visually perceived elements, but also the constructive and material culture that gave birth to this extraordinary habitat. List of References Allen, E. 1969, Stone Shelters, Massachusetts Institute of Technology, Cambridge. Ambrosi, A., Degano, E. & Zaccaria, C.A. (ed.) 1990, Architettura in pietra a secco, atti del 1’ Seminario internazionale, Noci-Alberobello, 27-30 settembre l987, Fasano. Ambrosi, A., Panella, R. & Radicchi, G. 1997, Storia e destino dei trulli di Alberobello. Prontuario per il restauro, Schena editore, Fasano di Brindisi. Battaglia, R. 1952, “Osservazione sulla forma e sulla distribuzione dei trulli pugliesi”, Archivio Storico Pugliese, V, pp. 34-44. Berteaux, E. 1899, Etude d’un type d’habitation primitive, Colin, Paris. Calderazzi, A. 1984, Architettura rurale nel territorio pugliese; ed. Schena, Fasano. Castellano, M. 1960, La valle dei trulli, Leonardo da Vinci, Bari. Costantini, A., “Le costruzioni in pietra a secco nel Salento leccese”, Italia Nostra Parabita, Lecce. Defacendis, S. 1991, Le ultime Capanne a Tholos. Nel territorio a sinistra del basso corso dell’Ofanto, Schena editore, Brindisi. Esposito, G. 1983, Architettura e storia dei trulli : Alberobello, un paese da conservare, Casa del libro, Roma. Grasso, G., 2000, Architetture in pietra a secco nel Salento, Edizioni del Grifo, Lecce. Simoncini, G. 1960, Architettura contadina in Puglia. Le forme a trullo, Vitali e Ghianda, Genova. Sisto, O. & Angiulli, G. 1961, Alberobello, città dei trulli, tip. De Robertis, Putignano. Tosi Di Mizio, E. 1983, Pietra, vita di trullo: descrizione, problemi, risorse, Vito Radio, Putignano.

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Azerbaijan University of Architecture and Construction, Azerbaijan

Saverio Mecca

University of Florence, Italy

Azerbaijan is notable for its architectural and archaeological monuments. Architectural monuments preserved up to the present day represent valuable information on the succession and progress peculiarities of typologically different buildings. The diversity of architecture and details, construction methods and decoration of corbelled domes in this region, situated in a region between the East and the West, has considerable importance in a wider scenario. Geography, natural environment, socio-economical context Variety and abundance of natural-climatic conditions has contributed to the development of Azerbaijan’s territory since ancient times: Azykh cave (Fizuli region of Azerbaijan), where eleven cultural layers belonging to different historical stages were discovered during archaeological excavations, is testimony to that. Such a variety of conditions posed differing architecturalconstruction problems for architects, creating a large number of varying types in the architecture of dwelling houses. Peculiarities of historical development in various regions of Azerbaijan influenced the appearance and the spread of different architectural types. Considerable seismic activity in several regions of the country has influenced construction methods also. Thus, local building materials, seismicity of the region, insulation, etc., all interacted on the architectural, artistic and constructional peculiarities of Azerbaijan’s corbelled architecture. Fig. 1: Family houses of Bronze Age

Urban and architectural morphology and function The ability of local architects to adapt the volumetric and planning composition of dwelling houses to local conditions and materials clearly demonstrates a certain level of local architectural and artistic development. Family houses (Fig.1) from the Bronze Age, dis-

Fig. 2: Corbelled erections in immemorial settlements (Reconstruction)

covered during archaeological excavations, as well as cave dwellings, are the most ancient dwelling type. Judging by a great amount of the immemorial settlements (6th-1st millennium bc), dwellings of that period were corbelled and round in layout. There were also several rectangular ground erections and semi-dugouts. Mud brick or cobblestone in combination with a rammed loam structure was used as building material. Such buildings had the aperture in their upper part Fig. 3: Distribution of corbelled domes

Presence of corbelling domes Qubba

Tovuz Göyçay

Gäncä

Agˇdam Xankändi Füzuli Sahbuz Naxçivan

BAKU

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Garadam, corbelled dome architecture in Azerbaijan

Sabina Hajiyeva

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Earthen Domes and Habitats Fig. 4: Corbelled erections in immemorial settlements (Plan of archaeological excavation)

Fig. 5: Interior of ancient Garadam with wooden overlapping structure over fireplace

Fig. 6: Different types of overlapping structures

over the fireplace, situated in the center of room (Gargalar tepesi, Gazakh region, 5th-4th mill. bc; Karakepektepe, Fizuli region, 3rd mill. bc; Gul-tepe, Nakhichevan, 5th-4th mill. bc; Ilanly-tepe, Garabakh, 5th mill. bc; Shomu-tepe, 6th5th mill. bc) (Figs. 2-4). Dwelling walls were clayed using minced straw for increased durability and floors were strewn with gravel (Mamed-zadeh 1983). Iron Age dwellings were mostly of the Garadam1 type, one of the most ancient kinds of housing. Garadam is a dwelling with a wooden corbelled dome, supporting columns (or without), an upper light-smoke aperture (badja in Azeri language) and a fireplace (tendir) in the middle of the room (Fig. 5). The main feature of garadam is the overlapping structure where the wooden corbelled dome (Fig. 6), with an upper light-smoke aperture in the middle of the roof, is formed by the forces of horizontally laid beams and timbers. A solid floor from converted timbers, small-scale branches and a dense earth bed is laid over the overlapping structure. The name garadam may originate from the Turkish as garanligdam, ‘dark house’, or without windows. It can otherwise be translated as ‘large house’ (Mekhtiyev 1987, p. 8). We may identify 3 types of garadam in Azerbaijan: - underground garadam (Fig. 7), - semi-underground garadam (Fig. 8), - above ground garadam (Figs. 9-12). Above ground garadams were more widespread than others. The existence of only one aperture (a door) demonstrates that the underground type was the first, semi-underground and above ground garadams being developed later. One could suppose that garadam is an upgraded dugout, with the burial mound remaining outwardly (Useynov 1963, p. 6). The house with its wooden roof supported with inner pillars could be cited as one of the most ancient houses in Transcaucasia.2 As a result of deep embedding of underground garadams, the entrance was like a narrow, covered and inclined corridor. The garadam itself remained a modest earthen mound. Interiors of garadams were very simple: walls were usually faced with coarse masonry; black smoke in the course of time covered the supports and beams with a solid, dark, sparkling tint. Change of social-economical conditions and gradual thinning of forests caused the appearance and development of new progressive dwelling types, 1

Fig. 7: Underground bi-cameral (segmental) garadam

Fig. 8: Semi-underground unicameral garadam

Garadams existed in some regions of Azerbaijan up to 19th century The region was described by Xenophon (5-4th centuries bc), and later by Vitruvius.

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Fig. 9: Above ground unicameral garadams

Fig. 11: Tri-cameral garadam

Fig. 10: Bi-cameral (segmental) garadam

Fig. 12: Multicameral (complex) garadam

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Fig. 13a: Djuma mosque in historical part of Baku- Icheri sheher

Earthen Domes and Habitats Fig. 13b: Multicameral (complex) garadam

Fig. 14: Djuma mosque in historical part of Baku- Icheri sheher

where only the back and partially the side walls were cut into the hillock. The overlapping structure was the same but without any internal supporting column and a facilitated construction. The main lower square of the corbelled dome was supported by walls. The upper aperture was for lighting only; smoke was allowed to escape via a special smoke duct. A classification of garadams Through a comparative analysis of all surviving garadams, we may propose the following classification: - unicameral house (where people live together with animals under a single roof) (Figs. 8-9); - bi-cameral (segmental), where living quarters are separated by a partition from the cattleshed (Figs. 7-10); - tri-cameral house (Fig. 11) consisting of two cattle sheds and a living room; - multicameral (complex) house (Mekhtiyev 1987 p.15) (Fig. 12). A unicameral garadam house has a corbelled dome resting on 4 (or 3 or 2) self-supporting inner columns. Two different wooden vault structures, rectangular and multi-angular (Fig. 5), were used in the overlapping of such a garadam. This type is similar to the Greek megaron (Mekhtiyev 1987, p.13). Other garadam types (bi-cameral-segmental and tri-cameral or multicameral) also included different utility rooms: cattleshed, granary, etc. We must note that garadam type overlapping was used not only for dwellings but in religious buildings as well. Djuma mosque in the old town of Baku, Icheri Sheher, was built in the place of two temples dedicated to fire (Fig. 13) (results of archaeological excavations: Useynov 1963, p. 36). A corbelled dome, ornamented with blue and green slip glaze, can now be seen in old photographs from the 19th century (Fig. 14). Unfortunately, that mosque was burned down and another mosque (which exists now) was built in its place. Garadams at Absheron peninsula. The Village of Gala Absheron peninsula is of especial interest as a region rich in architectural heritage: the history of Absheron began long before the ad period. Burial mounds of 3rd-2nd millennium bc discovered during archaeological excavations and the rock petroglyphs of Gobustan demonstrate the deep historical roots of that area. Unfortunately garadams have been preserved only in a few villages of

Azerbaijan. One of such village is Gala3, situated in the north-east of the Absheron peninsula. It is different from the other Absheron villages for its unique architectural character. The architecture of the village of Gala corresponds to the Absheron traditional architectural features, which were connected first of all to natural factors: lack of timber but large quantity of limestone, cold winds in winter and hot, dry winds in summer, lack of water sources, etc. Archaeological excavations are testimony to the existence of pre-historic settlements in this area dating from the 3rd millennium bc. However, dwellings and utility buildings preserved today could date from the 14th-19th centuries. The villageâ&#x20AC;&#x2122;s territory is over 200 ha. There are 5 mosques, 3 bath houses (hamam), 4 water reservoirs (ovdan), dwellings, utility buildings, tombs, mausoleums, burial mounds and ruins of fortifications, all preserved to date. The historical ambience of the 3rd millennium bc is well preserved there due to its distance from Baku and other villages which left this area little known up to middle of the 20th century. Some erections preserved in this village are of the unicameral type (Figs. 15a-b). Mostly, however, houses consist of two rooms: one was used as a living room, another one as a kitchen (Fig. 16). Some houses consisted of many rooms (Figs.17a-b) with an oven for bread baking (tendir), as well as a fireplace located in the kitchen for food preparation and the heating of water. The presence of a tendir and fireplace led to the appearance of double (twin) cone-shaped cupolas with upper apertures (Figs. 18a-b). There is a peculiar water course in the corner of one of the rooms. The water course in the form of a deep channel was constructed at floor level and does not have any partition from the kitchen. Opposite the water course there is small platform surrounded by a low wall (15-20 cm) connected to building. A hole on the platform surface drains the water toward to the street. Rainwater was used for washing and the Islamic ritual lavabo (gusul) before prayer. One could mention that this was a unique element, a prototype of the modern shower cabin in the medieval houses of Gala citizens. Not simply a bath house, which were widespread in the East, but precisely a shower cabin, The Gala Village was proclaimed State Historically-Ethnographical Preserve by order nÂ° 457, by Azerbaijan Ministers Cabinet in 1988.

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Fig. 15b: Houses in Gala Village, unicameral type Fig. 19: detail of corbelled dome in Gala Village Fig. 20: detail of corbelled dome in Gala Village Fig. 17b: House in Gala Village, double-domes type

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where people were washed 5 times a day before prayer. One other interesting feature is that, in spite of the enfilade of rooms, each room has its own gate to the yard. In reference to investigations, twin-dome houses appeared as the result of further development of the semi-underground domed utility building, usually dug into the earth 2-2.5 meters or placed at ground level. Interiors are of particular interest: there are special feedboxes and stone fastenings to the walls for animals. It is necessary to note that houses situated in the area surrounding a cemetery are also of special interest. The type of building contributes to temperature reduction inside the house: a dome shape, compared to a flat roof, contributes to reduced heating of the overlapping and faster cooling. Materials and building techniques Houses in Gala were constructed from white limestone (Figs. 19-21). They Fig. 15a: Houses in Gala Village, unicameral type Fig. 16: Houses in Gala Village, bi-cameral type Fig. 17a: House in Gala Village, double-domes type Fig. 18: House in Gala Village, tendir and fireplace corresponding to the double (twin) cone-shaped domes with upper apertures

usually have domes over ovens, smoke ducts and stone rainwater leaders. According to Atakishiyev K. (Aliyeva R. 2007, p. 73) “these are the first garadams in stone.” “In many Azerbaijan regions, garadams were constructed from wood, but here, in Absheron, lack of wooden and abundance of stone materials created a new type of stone garadam. We may find such houses only in Absheron (within Azerbaijan)” (Aliyeva R. 2007, p. 4).4 Architrave beam-type construction was used as an overlapping structure in corbelled erections. Architrave structures through trumpet arches cover all the space over walls, forming a cupola. There are several types of overlapping constructions: - The Arch structure, which transfer the vertical and horizontal load to the walls. Walls are of 70-90 cm thickness to maintain the inner microclimate and are constructed in clay mortar. The floor is stone or of clay and thatch mix. - The flat post-and-beam structure is very rare. It consists of wooden beams with clay laid down over a clay and thatch overlapping. Kepfer, European traveler of 17th century, gives some ethnographical features of Gala village (Aliyeva R. 2007, p. 4); Zelenskiy, Lerkh and Berezin write in their works about village. Drawings of Pakhomov and Csheblikin are of special interest.

1 2 3 4

Evaluation of the state of conservation and pathologies Gala corbelled buildings are of special interest as rare types. Their layout peculiarities demonstrate a genetical connection to ancient garadam

houses, but at the same time have their own originality and uniqueness. Unfortunately there is a lack of preservation and rehabilitation of the houses as much as the historical ambience around them. Some architectural monuments, well known from previous investigations conducted 20-30 years ago, no longer exist. Many have lost their originality as a result of incorrect restoration or repair works. On the initiative of the Foundation Heydar Aliyev, the first historical-ethnographical open-air museum complex was founded in Gala in 2008, a move to promote the preservation of the monuments of Gala.

List of References Akhoundov, D. A 1986, Arhitectura drevnego I rannesrednevekovogo Azerbaidjana (in Russian), Architecture of Ancient and Early Medieval Azerbaijan, Baku Alizadeh, G., 1963, Narodnoe zodchestvo Azerbaijana I ego progressivnie traditsii (Russia)/ Azerbaijan folk architecture and its progressive traditions, Publishing House of Academy of Science of Azerbaijan, Baku Aliyeva, R., 2005, ‘Gala kendi-Tarix-etnografiya gorugu (Azery)’ (Gala Village- Historically-Ethnographical Preserve), Gobustan, vol. 4, Baku Aliyeva, R., 2006, Gala kendinin mulki memarligi (Azery), (Civil architecture of Gala village), Chashioglu, Baku Aliyeva, R. 2007, Unikal Gala kendi (Azery) (Unique Gala village) Teknur MMC, Baki Mamed-zadeh, K., 1983, Stroitelnoe iskusstvo Azerbaijana (Russian) (Construction art in Azerbaijan), Elm, Baku Avalov, E., 1983, Arxitektura (Russian) (Architecture), Yazichi, Baku Bretanitskiy, L. 1966, Zodchestvo Azerbaijana 12-15 vekov (Russian) (Architecture of Azerbaijan of 12th -15th centuries), Nauka, Moscow Fatullayev, Sh. 1986, Gradostroitelstvo I arxitektura Azerbaijana 19-nachala 20 vekov (Russian) (Town planning and architecture of Azerbaijan of 19 th-early 20th centuries), Stroyizdat, Leningrad Fatullayev-Figarov, Sh. 2003, Zodchestvo Absherona (Russian) (Architecture of Azerbaijan), Chasioglu, Baku Guliyev, E. 1998, Absheronun yashayish evleri va tikinti medeniyyeti (Azeri) (Residential houses in Absheron and construction culture), Azerneshr, Baku Hajiyeva, S., 2005/2006, ‘Residential houses of North-Western District of Azerbaijan’, Science without borders, Transactions of the International Academy of Science H&E Volume 2, ISBN978-9952-25-049-7, ICSD/IAS, Innsbruck Mekhtiyev, A.M. 1987, Derevyannoe zodchestvo Azerbaidjana (in Russian) (Wooden architecture of Azerbaijan), Elm, Baku Mekhtiyev, A.M. 2001, Narodnoye jilicshe Azerbaidjana (Russian) (Folk dwelling in Azerbaijan), Tebriz Salamzadeh, A., & Sadigzadeh A., 1961, Azerbaijanuin 18-19 esr yashayish evleri (Azery) (Azerbaijan residential houses of 18th-19th centuries), Azerneshr, Baku Useynov, M., Bretanitskiy, L., & Salamzadeh, A. 1963, Istoria arxitektury Azerbaijana (Russian) (History of Azerbaijan architecture), Nauka, Moscow

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- Mix roof from arch and post-and-beam structure. The existence of several overlapping systems does not influence the exterior of the building. However, it can sometimes be seen in the different height of the rooms. Interiors are also of special interest. There were wooden niches, shelves or ref, on the upper part of the walls as decorative elements. Cups, copper tableware, trays and such were put on the shelves. Chests, mattresses and blankets were put into niches and act as so-called interior decoration. Lamps and small niches for the Koran are other decorative elements. New houses were constructed later, at the end of the 19th and beginning of the 20th centuries. Those were houses with many rooms, integrated to old houses (mostly houses of affluent people or large families); new twostoreys houses; and one-storey houses with many rooms and twin cupolas (as result of traditional house development).

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AN INTERDISCIPLINARY METHOD

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University of Florence, Italy

The corbelled dome architecture of Syria represents a valuable example of vernacular architecture and a unique cultural landscape that is the result of a process of interaction and adaptation of communities to the environment with scarce natural resources over thousands of years. Vernacular architecture is the result of this rich and complex process that begins with the formation of a particular social and cultural structure in close relation with the environment, and this is reflected through the establishment of certain rituals and traditions, where the architecture is the technical response of the community to the need for spaces. In Syria, this technical response materialized in a particular kind of architecture: corbelled dome buildings with the earth as the basic and almost sole constructive material. These constructions, so removed from well-known typologies, are the result of the immaterial heritage (local constructive knowledge transmitted from generation to generation) together with the material (the architectural objects, made with earth as a natural resource suitable for building material), and so they cannot be studied separately. A deep interdisciplinary method of analysis is required that includes the architecture as part of a system that has to be studied along with, and not detached from, its environment, a deep knowledge of the environmental and cultural context and all the factors that brought about the architecture being necessary. The cognitive system that is behind vernacular architecture is part of a much more complex knowledge system, for which practices and representations are integrated and mutually dependent, including language, relationship with place, beliefs and world views, and so ‘tacit local knowledge’. This tacit local knowledge must be codified in a systemic way for its understanding, in order to collect information and transfer the knowledge as a way of documenting cultural heritage (Fig.1).

Codified Knowledge

Tacit Knowledge

General Knowledge

Knowledge as Common Goods.

Tacit General Knowledge

Generally applicable and accessible, can be transferred with the conventional vertical teaching and its rediscovery enhances ownership Local Explicit Knowledge

(Grammar rules of the language), taught in a horizontally way and can be partially codified and taught vertically

Local Knowledge

Local Tacit Knowledge

Even if available from the centre, it should be The heart of the problem. reinvented for local ownership Characterizing a local system. Combines horizontal learning and local reinvention. Figure 1: From local tacit knowledge to local explicit knowledge

An interdisciplinary approach The project has been based on an interdisciplinary scientific research joining an in-depth study of local architecture, the representation of architectural knowledge and a theoretical and experimental scientific analysis and interpretation. The interdisciplinary scientific method of research started with the in-depth study of local architecture during the on-site mission of MayJune 2008, where the all experts worked on the different aspects of architectural heritage. The fieldwork focused on the analysis of three geographic areas of northern Syria: – the west region of the lake Jabboul; – the west region of the lake Al Assad; – and the east region of Hama. These regions were studied at several investigation scales, in order to have a complete analysis. The tools used on this first approach were: – Technical sheets for the identification, documentation and analysis of: urban and architectural morphology of villages; architectural morphology of houses; building technology;

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An interdisciplinary approach to a cultural and architectural heritage

Saverio Mecca Natalia Jorquera Silva

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building elements; building pathologies and causes; lifestyle; – Direct surveys: manual methods; topographic methods (theodolite); three-dimensional (laser scanner); photographic survey; – Mechanical testing; – Sampling of materials; – Interviews with builders and inhabitants. The fieldwork produced a large set of data and qualitative and quantitative information, which has been the basis for the more traditional scientific analysis and interpretation through the collaboration and integration of different scientific approaches to urban, architectural, technical, archaeometrical, structural, geographical and environmental dimensions. The different scientific activities were organized so that each partner has been intertwined with the others in a multi-directional way sharing data, information and knowledge, all converging at the goal of the project: the vernacular architecture knowledge system analysis and modelling (Fig. 5). Within this structure as exemplified in Figure 5, each research line worked with different modes, procedures and methods using both traditional and advanced data gathering techniques. Thus, the urban and landscape, the building system and the architectural and functional analysis, were mainly based on data and information directly extracted in the field through traditional survey methods, which were integrated with the information produced by the geomatic analysis, using all the direct surveying methods up to the 3D modelling by a laser scanner. The mechanical analysis made use of both traditional survey and on-site testing methods integrating them with the information coming from building system and geomatic analysis. The mechanical tests conducted in a laboratory on materials, on a scale model and on a numerical model to simulate the structural behaviour were supported by the detailed information on shape and dimensions of the dome produced by geomatic analysis; on the other hand, the archaeometric analysis used the latest analysis tools and techniques for the accurate laboratory analysis of mineralogical composition of materials sampled during the Fig. 2: Different phases of the fieldwork: observation of a maintenance process. Fig. 3: Different phases of the fieldwork: interview with the inhabitants. Fig. 4: Different phases of the fieldwork: direct survey.

Fig. 5: Conceptual scheme of analysis and modelling of a tacit local knowledge system

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field mission. The resource and environmental analysis, as well as the ethnographic analysis has been developed in field by several interviews with people living in the villages and with building specialists, integrated with the scientific literature on people living in the selected regions of corbelled dome villages. The new information and knowledge was consolidated in order to gain a complete perspective of the subject for each discipline, but at the same time, a systemic information that enabled the modelling of a detailed representation of the architectural knowledge, and so a codification of tacit local knowledge. Tacit local knowledge representation The tacit local architectural knowledge is the result of several factors, and to understand them and make them explicit and sharable, we need an interdisciplinary approach based on knowledge such as that outlined and applied in the project. As shown in Figure 1, the analysis and modelling of local knowledge systems is at the heart of the work of cognitive inquiry, as a result of an integration process of all the specific knowledge areas, that is the basis for initiating a recovery process. Urban and Architectural analysis The urban and architectural analysis of architectural forms and functions starts from the identification of the basic architectural elements, their technical, functional and morphological characteristics and of spatial and functional relations. In this way the modes of aggregation of individual cells that give shape to urban and housing units, are analysed and characterized. This type of analysis is based on direct observations and documentation,

Fig. 6: A cultural landscape: a natural environment transformed by a community.

through analysis cards, implementation of direct measurements and information collected from interviews with inhabitants. Geomatic survey The whole set of geomatic surveying methods has been used, from direct and topographical methods to sophisticated methods of acquisition such as photogrammetry, â&#x20AC;&#x2DC;laser scanningâ&#x20AC;&#x2122; and digital photogrammetry for a 3D model and information on materials and surfaces. Building Technical analysis The analysis of the local tacit constructive knowledge system has been based on the direct observation and surveying of building elements, on the identification and characterization of materials, on building technique and construction process identification. Archaeometric Analysis The archaeometric analysis is based on sampling materials of the buildings for characterizing the mineralogical composition, determining particle size, the physical (plasticity index, porosity) and mechanical parameters, the origins of materials, the mixtures of soil and additives, the methods of mixture and characterizing the degradation process.

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Earthen Domes and Habitats Fig. 7: A cultural landscape: a natural environment transformed by a community.

Mechanical Analysis The structural or mechanical analysis is based on the direct surveying, the deep insight of building elements and their static schemes, identification and diagnosis structural pathologies, and an archaeotechnical interpretative analysis of the construction. The purpose of this analysis is the understanding and identifying of the structural characteristics of constructive culture, structural pathologies and failures.

Conclusions The traditional architectural techniques and the local, cultural, social organization and rituals of people living in the arid margins region of Syria highlight the close relationship that has existed over the centuries between human communities, technology and the natural environment, and so they have to be studied with a systemic approach. An interdisciplinary systemic approach may allow better understanding of the architectural local knowledge in order to identify, characterize, document and outline the actions for a sustainable conservation of a cultural landscape.

University of Florence, Italy

Konstantinos Tokmakidis

Hellenic Society, Aristotle University of Thessaloniki, Greece

Metric documentation of cultural heritage requires a thorough understanding and careful observation of the site and suitable graphic restitution of the data collected, as well as dimensional quantification using appropriate instruments. Documentation projects are particularly important in cases where the heritage is, for whatever reason, in a precarious state. It is, therefore, important to collect documentation as thoroughly as possible: geomatic methods can be applied to generate permanent records from which information can be extracted (Fig. 9). The complexity is an inspiring challenge and contingent difficulties constitute an effective stimulus towards finding better solutions and to improving research methods for vernacular architecture: - as the preliminary knowledge of the villages is most of the time limited, we need a certain flexibility when setting up the on-site survey operations; - environmental and climatic conditions often constrain the use of surveying instruments; - the presence of experts from diverse fields may highlight different and new requirements for spatial data collection. Recording is a key activity in the conservation management of cultural heritage. Conservation-related information is usually obtained (certainly in the case of this project) from multi-disciplinary research activities. In project teams with multi-disciplinary expertise, geomatic techniques can be used to construct a reference base that enables all members to meaningfully participate in both investigative procedures and project development and application. The management of spatial data The management of spatial data often requires specialist skills making it

Fig. 8: The geomatic study as a part of the analysis and modelling of a tacit local knowledge system.

difficult for experts in other fields to use raw data. So geomatics not only plays a vital role in the data acquisition phase but it is also important for data management and interpretation, acting as a â&#x20AC;&#x2DC;filterâ&#x20AC;&#x2122; between raw data and graphical information (Fig. 13), (i.e. the transition from the points model to characteristic sections) that has to be structured in such a way that experts in different fields with a basic or mid-level knowledge of CAD, image processing and new technologies can use it autonomously. Recording spatial data requires, in the first instance, the collection of available materials, on the basis of which preliminary observations are made and further operations are planned. So there is initial off-site activity, followed by on-site verification and integration: - Off-site: existing sources are generally available for smaller-scale documentation: small-scale topographic maps, satellite images, aerial photos and sometimes, architectural sketch drawings; satellite images are now available almost everywhere though their quality should always be checked

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Geomatic methods of surveying

Grazia Tucci Valentina Bonora Alessia Nobile

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(image resolution, cloud coverage, data acquisition, spectrum, etc.); - On site: photos and instrumental survey: GPS, total station, photogrammetry, laser scanning, direct measurements; The level of detail Recording should be undertaken to a level of detail that provides the information required for appropriate and cost-effective planning and development. The need to provide documentation at different scales highlights the usefulness of integrating the various levels of detail in the same project. At the apex of the pyramid-shaped drawing are the inventories, the most basic form of documentation. They require ‘identification’: in our case every village had to be first recognized, then geo-referenced and memorised; sometimes other basic attributes were associated with a given position. At the base of the pyramid drawing are the highly detailed 3D models, where the level of detail is such that even the texture of the constituent materials is described (Fig. 13). The various operations undertaken in the Syrian villages occupy the middle area of the pyramid: - positioning the various villages in the territory; - documentation of the arrangement of the settlements, i.e. the spatial relations between the habitative units which, despite being quite autonomous, share spaces of which the ‘pseudo-urban’ nature is one of the elements being studied; - survey of a single dwelling, including the rooms used for living, the central court and the accessory structures (oven, stores, animal shelters); - documentation of the technical characteristics of a typical cell. The survey methods Survey methods and the resulting documentation have to meet project requirements and objectives and be appropriate for the cultural context and the resources available. Geomatic techniques are almost always not intrusive as remote sensing is deployed at a distance from the object being surveyed. This technique has the advantage of completely preserving the object but it can usually only be used on the external surfaces of the object. Fig. 9: Scheme of geomatic base map. Fig. 10: Traditional photographic image. Fig. 11: A 3D model image.

Fig. 12: From raw spatial data to information: recording improves understanding. Fig. 13: Pyramid scheme showing relations between graphical scale, data resolution, and level of detail. Fig. 14: Orthoprojection: for each pixel of the orthophoto (above) the corresponding pixel on the frame (bottom) is calculated, depending on the model of 3D form (centre). Through the appropriate interpolations we may obtain a photographic image in orthogonal projection, free from any perspective deformation.

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In this context the term multi-resolution survey is appropriate because data density is gradually optimised by applying different instruments or by regulating the acquisition parameters: in this way the information density is correlated with the formal complexity of the object to be measured. If we consider a village observed from a long distance away, i.e. from a viewpoint that sets it in the context of the surrounding territory, it can be represented as a point on a map or on an aerial photo, or stored in a DB as standard longitude and latitude coordinates. Moving the observation point closer, it may be useful to schematise the structure of the buildings that make up the village. To this end the buildings can be considered modular. The modules are defined with an approximation that highlights only the most relevant dimensional differences of the cells without making the description less effective. It is possible to distinguish larger and smaller modules (the first are generally used for dwellings or as stores, the second as kitchens, ovens or secondary rooms), identify the open areas associated with the modules, ascertain the position of the mastaba and indicate the presence of external dividing walls. A more detailed observation will focus on just one of the dwellings. At this scale the following factors have to be considered: are the structures aligned or not; how do the dwellings vary with respect to the module; what type of terrain morphology (particularly important for water drainage); and how are the dwellings aggregated (isolated, aligned along a road or path, grouped in other ways)? When the observation point is moved even closer, the technological elements of the structure are revealed: arches which connect the internal spaces, niches in the brick-work, openings for aeration, window and door frames, the integration of elements in wood and stone in the architraves of the openings, the tantour of the domes, and individual bricks. Manual inspection, sketches and recording of detail are usually indispensable at this analytic scale. To obtain such results a possible approach is to combine different sensors, such as GPS, satellite imagery, total station, digital cameras, and laser

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Earthen Domes and Habitats Fig. 15: Total station surveying in Oum Amoud Seghir village. Fig. 16: The multi-resolution survey by applying different instruments.

scanners (Fig. 16). A data fusion approach involves measurements at different levels: wide-range measurements are based on satellite or topographic systems, while close-range photogrammetry or laser scanning is suitable for small-scale detailed recording. A multi-resolution approach requires the application of multi-sensor acquisition techniques. The presence of different scales in the same survey project shows the usefulness of integrating the various levels of detail. On the technical side we currently have a broad range of recording techniques at our disposal: these need to be combined in order to best match project requirements because of the complexity of some heritage structures and the lack of a single method capable of providing satisfactory results in all measuring conditions. The principle that can be derived from the above-described approach is the same as that which guides all correct survey procedures: it prescribes starting with general information and then proceeding to more specific

detail, i.e. a very small number of points are ascertained with high precision (the number of points has to be kept as low as possible because operational costs increase proportionally to the degree of accuracy required). A ‘cascade’ procedure utilizing measuring procedures that become increasingly simple is then adopted to determine the detail points that describe the form of the object. A common reference system, usually defined by topographic parameters, makes it possible to acquire different objects and to highlight the relationship between them. It is important that the data acquired in the various phases be subjected to quality controls, i.e. its usefulness and accuracy should be checked. Rapid acquisition on-site is important when distance and inaccessible sites make long survey campaigns both difficult and expensive. Among the factors influencing the choice of instruments used in Syria were portability and operational autonomy. A GPS receiver, a total station, a digital camera, and a laser scanner were used. A common characteristic of all the data acquired is its numerical nature: information management is facilitated when digital heritage recordings are used and there are immediate benefits in terms of project planning, interdisciplinary communication and result evaluation. A digital model obtained using modern metric surveying techniques is always three-dimensional and it can provide structural and architectural outlines, profiles, cross-sections and contour lines and also detect features of interest and print a solid model. Digital images The simplest and most widely used technique for documenting cultural heritage is certainly photography: the content is richly informative (albeit exclusively qualitative) and easily acquired. The use of digital images for metric surveying is well consolidated: photogrammetry and some scanning systems are classified as ‘image-based’ survey techniques. Among the digital images used in the project for taking measurements were: - Satellite imagery: an established technology that has yet to be fully optimized; for a given area, views (generally monoscopic) acquired at different times are often available and this enables any changes that have

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taken place in a dwelling structure over that time period to be interpreted. Both raw and ortho-rectified images (accurately geo-referenced, â&#x20AC;&#x2DC;map readyâ&#x20AC;&#x2122; images) are available; - Photograms: the generic definition for both aerial and land photographs that can be used to obtain dimensional information in a photogrammetric project. The following graphic representations can be obtained: vectorial restitution of the main features or detail points, range maps, rectified images and orthophotos. The synthesis image, another type of image that was widely used for the project, does not depict real objects but renders the views of models

Fig. 17: Comparison between the laser scanner survey model and the picture (pag. 162) of the real housing unit.

acquired using a laser scanner: a quite realistic texture can be achieved directly from the intensity value provided by the laser scanner as an attribute of each point. The points model can be visualized with various degrees of shading and on different chromatic scales. Efforts were made so the renders used in the project evoked black-and-white photographs as much as possible (Fig. 17). On the render it is possible to identify the pattern of the brickwork,

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Earthen Domes and Habitats Fig. 18: Comparison between the laser scanner survey model (pag. 161) and the picture of the real housing unit.

recognize a wall built of the same-sized stone blocks, stones and earth or bricks (the difference between stone work and mud bricks can be perceived) and to ascertain the existence of plaster and its state of conservation.

Information relating to colour can also be obtained: although there is not a complete correspondence with real colours, there is a clearly visible difference between the walls that have been white-washed and those that have been plastered using mud and straw, and paintings on the facades testifying to pilgrimages to Makkah are recognizable.

Politechnic University of Valencia, Spain

Letizia Dipasquale

University of Florence, Italy

The northern Syrian villages retain a strong formal expression of the nomadic Bedouin culture, which is manifested in the way the different units that shape the settlements are grouped, in the organization of the community space, in the use of housing for basic needs (sleeping, eating) and the predilection of the outer space for the remaining activities. The shape of the house that evokes a tent, and also the shape of the urban settlements, were born spontaneously and evolved over time as a response to human needs in relation to the environment; therefore, the morphology does not respond to an aesthetic factor, but to a thorough knowledge of the territory and to social and cultural needs. The urban and architectural analysis is the first approach to the research: ranging from a general to a particular scale, the urban and architectural analysis provides a primary overview of the various villages, in order to compare them and make an initial identification of the different architectural forms. At the same time, the architectural analysis is the basis for understanding a language developed by a culture as a way of modifying its natural environment, and as a result formed a cultural landscape of such exceptionality as northern Syria. Research method The urban and architectural analysis is focused on the recognition and understanding of the architectural elements, their technical, functional and morphological characteristics and of spatial and functional relations that gave origin to the individual cells and to the settlements of corbelled dome architecture, in order to: - identify, characterize and document the different types of settlements (the components and their relations); - identify the use of the different spaces in each village;

Fig. 19: The urban and landscape analysis and the architectural and functional modelling as a part of the analysis and modelling of a tacit local knowledge system.

- identify the state of conservation of each village; - identify, characterize and document the different architectural typologies of domes; - identify the use and relation between the inner spaces of housing units; - identify and characterize the architectural elements, their forms and dimensions (access, openings, stores, etc.). The research method is based on different kinds of analysis, like direct observations, documentation, elaboration of analysis sheets, implementation of direct measurements and information collected from interviews with inhabitants. After the first visit to the villages and its respective fieldwork analysis, the urban and architectural study was divided into two parts, each one with its own methodology: the urban morphology of villages and the architectural morphology of houses.

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Urban and architectural analysis

Fernando Vegas Camilla Mileto Valentina Cristini

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The urban morphology of villages The goal of the analysis is to obtain a simplified, ordered and standardised reading of the urban landscapes, to establish a comparative analysis of their morphology and components. The study starts with the production of graphic material (pictures, plans) that is the base for the urban morphology analysis. The analysis process As a part of the process, two levels of studies were chosen, one of a larger scale, the country level, useful for the comparison of different villages, and one specific, the village level, that is based on the analysis of the components and their relations to each other inside each village. Country analysis goals - identify and classify villages; - identify types of villages: with dome buildings/without dome buildings; - highlight their geographical location and context. Village analysis goals - identify the components of the village: buildings, squares, paths, canals, vegetation; - classify the types of buildings and their state of conservation: domed/flat roof building, in use, abandoned, private, public, etc. Documents Elaboration of graphic material - aerial picture from Google Earth use as the base for elaboration of first preliminary plan (scale between 1:2,000 and 1:4,000); - aerial more detailed picture as the base for analysis plan; - identification of the state of conservation of the villages through the incorporation of symbology in each plan: types of buildings, use, materials, etc.; - complementation of the information with photographs taken in the fieldwork. Descriptive sheets Elaboration of descriptive sheets with information about: accessibility to the villages; village development; housing unit development; trails in the village; water paths; vegetation.

Figs. 20-21-22: The elaboration of graphic material: the analysis plan made from an aerial picture and photographs taken in the field work as a complement to the information

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Earthen Domes and Habitats Figs. 23-24: The different scales of the architectural morphology: the analysis of the outdoor and indoor spaces, their function, distribution and the relations among them

The architectural morphology of houses Through the housing units survey made with the topographic and laser scanner methods it is possible to analyze the distribution, functional and constructive character of the buildings in order to: - analyze the possible forms of combination between the basic cells (single or double dome); - identify and compare the basic functional areas of the housing unit and the architectural solutions adopted (materials and types); - compare the different types of spatial and functional organization to identify variants and constants;

- understand the ways to inhabit; - analyze the system, distribution and drainage of the water; - document examples of significant housing units. Additionally, it is possible to identify different dome typologies to allow us to: - define the most recurrent and significant constructive types from the variety of domes observed; - identify the main characters that distinguish one dome from another; - describe the main characteristics for each type and possible variants; - understand the relationship between the aesthetic and formal aspects from the structural aspects of the buildings. The analysis process Fieldwork research - photographic documentation; - direct observation of a large sampling of domed buildings; - fill-in of analysis sheets and survey of typological, distribution and constructive characters; - geometrical survey of a housing unit. First elaboration phase archive; classification; comparison. Second elaboration phase description of aggregation types; description of architectural elements: dwellings, access, openings, courts, terraces, stables, stores, bathroom and kitchen; description of domes typologies: simple dome, Sultan dome, stone basement dome, flat roof dome, cob dome. Documents Elaboration of graphic material Graphical representations of the types of housing units and domes typologies were elaborated from the examples observed and surveyed, in which shape, size, and materials used are highlighted. Descriptive sheets The descriptive sheets define: - the structure of the housing, with the identification of the main types of combination of basic cells; - the organization and the use of the spaces in complex housing; - the identified dome typologies, with the description of the diffusion area, the geometrical, dimensional, and constructive aspects; - the bioclimatic aspects of the domed houses.

University of Florence, Italy

Patrice Morot-Sir Jean-Jacques Algros Ă&#x2030;cole dâ&#x20AC;&#x2122;Avignon, France

Research on vernacular architecture such as the corbelled domes of Syria needs to deepen tacit building knowledge, working on the analysis of building materials and techniques, on the constructive process modelling and on technical risk analysis. Therefore the technical research is focused on the recognition and understanding of the building elements and systems of corbelled dome architecture in order to: - identify, characterize and document the building system (elements and relations); - identify and model the building process; - identify the points of weakness, technical risks and the degradation dynamics; - identify actions and methods for the technical conservation of architectural heritage. Research method The research method is based on different kinds of analysis, aiming to collect more significant and reliable data and information. Direct observation and surveying, material, building elements and construction process identification are all part of the different study phases. The fieldwork began by visiting the selected village and conducting a careful and systematic analysis of buildings, according to the following steps of investigation: - reconnaissance and detection: geometric survey, material survey, - construction process method; - interviews with local experts; - direct observation of the construction process; - collection of samples; - identification of pathologies and failures and degradation diagnosis. As a supporting tool we elaborated a set of analysis sheets, in order to maxi-

Fig. 25: The technical study as a part of the analysis and modelling of a tacit local knowledge system.

mize the data collection on the fieldwork, to guide the retrieval of and to compare the gathered data and information. The geometric survey provides a detailed observation and measurement of the various components of the building and the connections between them. The material survey leads to the identification of the materials and layers of the building. A deeper analysis of the materials has been achieved through archaeometric analysis. A specific attention was devoted to the environmental analysis, for an understanding of the relationship between building technology and the local availability of materials. All this data and information was the basis for the questionnaire and the interview scheme. Interviews with local experts and observation of the production of earthen bricks and construction sites have focused on the construction process and building rules. The integration and elaboration of gathered data and information through different methods, to comprehend a modelling of the constructive culture of the corbelled dome villages of Syria, relied on the experience and competence of researchers.

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Constructive analysis

Saverio Mecca Letizia Dipasquale Natalia Jorquera Silva Silvia Onnis

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Documents Inventory of building elements The elements have been classified according to their role within the building (foundations, walls, roofs, openings, domes, pendentives, etc.) and to the materials. The different sets of building elements have been identified. The goal is to draw up a glossary of typical elements in order to represent them in a systematic way. Descriptive sheets A technical description of building elements has been defined. The set of data gathered on the fieldwork has been processed into descriptive sheets in order to highlight and compare the different parts and the constructive process of each item. The descriptive sheets define: - the single parts of the item, specifying the materials, size and disposition; - the integration modes of single parts (the use of mortar for masonry, or door jambs in the case of wooden structures); - the integration modes with other building elements (building assembly details); - a detailed representation of the elements through plan, vertical section, elevation, and axonometric and perspective views, highlighting the dimensions and relationship between the parts. A technical description of building elements allows comparison of the various techniques for evaluating the strong and weak points, the technical risks and give the basis for the structural analysis of mechanical behaviour. Modeling the constructive process A constructive process modelling, based on information gathered from interviews and site observations, allows us to identify each part of the construction process for the achievement of the examined element. By studying each elementary operation and the possible steps of the process control, the points that create risk factors or weakness into the system are further identifiable. This step is crucial in building systems analysis, as it facilitates the identification of possible weaknesses and potential improvements to the traditional technique.

Fig. 26: Direct observation of the rendering maintenance process of a housing unit. Figs. 27-28: Identification of different constructive elements.

University of Florence, Italy

Adolfo Alonso Durá

Politechnic University of Valencia, Spain

Any strategy directed to the conservation and protection of architectonic heritage needs to involve structural and mechanical aspects. In order to correctly identify such aspects and to find static analysis able both to describe and to understand the examined architectures, various structural surveys and specific methodologies of testing are necessary. This extended approach is particularly needed whenever we study traditional and vernacular buildings. These architectures and the related techniques are too far from well-known typologies, but even the building material appears certainly non-standardized and variable. In all these cases the mechanical behaviour and durability strictly depend on specific (local) conditions. So we need a deep knowledge of all the elements involved and characterizing the building process: we can reach such an aim through a specific methodology of investigation.

Fig. 29: The mechanical study as a part of the analysis and modelling of a tacit local knowledge system. Fig. 30: Direct observation of the building techniques.

Mechanical surveys and on-site and in laboratory testing The methods of investigation used to identify the main characters – from a mechanical point of view – of the domed buildings, are based on an awareness of the profound bond that exists between construction aspects in the strict sense, the nature and properties of materials, and structural functioning. The analysis of the artefacts was therefore carried out on three main levels. First level of analysis A first level of analysis has been developed in the field, through the survey of geometry, dimensions, technical solutions and the general organization of the devices (Fig. 30). The aim of the analysis is to discover within the great variety of cases the underlying shared building rules, which have few variations upon which to base an interpretation aimed at identifying the deeper structural reasons. It is now clear that building knowledge specializes according to several factors, whether environmental, social, economic or cultural. Among them the reasons of ‘firmitas’, or the need for the artefacts

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Structural analysis

Mirta Paglini Luisa Rovero Ugo Tonietti

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to last and possess good statics and functionality (given the conditions), are essential. In this regard, therefore, we tried to discover the motivations behind the solutions observed (type of laying bed equipment, slope, quality of toothing, special devices, etc.) discovering, within the context of blatant weaknesses (cracks, unbalances, collapses and subsidence), a vehicle for the comprehension of structural behaviour within the context of an interest in the construction processes (highly important for the mechanical performance). Interviews with master builders on the different stages of the building process were performed in order to gain information on the building processes and in order to further comprehend the buildersâ&#x20AC;&#x2122; intentions. Second level of analysis A second aspect of the method of enquiry concerns the identification of the materials employed and their role in endowing good mechanical performance (Fig. 31). This further level of analysis is aimed at identifying the nature and state of components and their quality from the purely physical-mechanical standpoint. We therefore begin with understanding the production process of the basic elements of the construction (bricks and mortars), analyzing the methods of mixing, forming, drying, implementation and protection; and we then proceed with understanding their physiochemical make-up (granulometry curve, Casagrandeâ&#x20AC;&#x2122;s plasticity index), in close connection with the archaeometric analysis, and finally we assess the characteristics of resistance to compression, elasticity, guided load displacement (with expression of ductility, etc.). To this end, during the survey campaign, many samples have been taken, both of brick and mortar and of plastering, with the intention of examining them. Third level of analysis Finally, a decisive phase in the analysis process concerns a simulation of the static performance, made through a comparison of complementary methods. This consists of a reproduction of the object consisting of an in-scale model and in the analytical and numeral assessment of the static performance of the devices based on specific hypotheses (Fig. 32). Both these methods have as their objective the perfecting of our comprehension of the building mechanism, highlighting efficiency, weaknesses and limitations.

Fig. 31: Setup tests. Fig. 32: Earthen in-scale model building.

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The making of a scale model is essential every time some construction processes appear obscure or difficult to simulate in a virtual manner, certain geometries, distortions and load conditions, both for the difficulties in managing the analytical model and for the intrinsic complexity of the real system. Wherever the simulation through a physical model has as its aim the comprehension of the construction process, the need to adopt a reproduction scale where basic elements, the bricks, are given their proper role and are identified in the execution technique, is essential. In the eventuality that we should need to carry out a real mechanical simulation, scale models may be subjected to a load test with a check up of tensions and movements, in a perfect mechanical analogy, following the protocol which refers to the Buckingham theorem. Analytical simulations, then numeral, are indispensable survey instruments for the assessment of the behavioural quality of the structure and, most of all, are useful for examining the variation of solutions alongside the variation of hypotheses or of assumed models. With such simulations we may discover which, among many, are the interpretations closer to reality, and

having tested (perhaps in relation to the results of experiments) the functionality of such hypotheses, we come to a classical description of the mechanical performance where tensions, prevailing directions, movements, maximum and minimum levels of stress, etc., are evidenced. As we know, calculation models that may be assumed, go from elastic-lineal models to models which take into account a scarce resistance to the traction of materials and of possible and compatible damage levels (until the introduction of slotted systems). The aim of analysis focuses on the conditions of the realization process, on the quality of the mechanical result and, finally, it is aimed at studying the compatibility with materials and the detection of optimal form conditions. All the procedures put into effect had as their fundamental objective the understanding of the structural arrangement, highlighting quality, originality and mechanical contents. The final description tries to capture, despite intrinsic uncertainties, the weaknesses and/or critical aspects, which would allow for maintenance or emergency measures to ensure the survival over time and the safeguard of these constructive devices that possess such originality and beauty.

The sciences of archaeometry and conservation concern the application of scientific methodologies respectively to the knowledge of the materials of the cultural heritage and to their preservation. Archeometry involves all the scientific disciplines, techniques and methods (material diagnosis and provenance, dating, paleotechnologies, etc.), able to extract from findings, artefacts and sites all the possible information necessary for a better knowledge of the objects. Conservation science is strongly linked and overlaps with archeometry; it deals with the study of decay processes, maintenance, and restoration of artistic and historical monuments and artefacts, being the basis for the preservation of cultural heritage. Extending from the original link with archaeology, archaeometry can be divided into the following areas: - physical and chemical dating methods, which provide archaeology with absolute and relative chronologies; - studies of materials incorporating provenance, technology, and use; - environmental approaches which provide information on past landscapes, climates, flora, and fauna, as well as diet, nutrition, health, and the pathology of people; - mathematical methods, such as tools for data treatment, also encompassing the role of computers in handling, analysing, and modelling the vast sources of data; - remote sensing and geophysical survey applications comprising a battery of non-destructive techniques for the location and characterisation of buried features at the regional, micro-regional, and intra-site levels. With regard to the study of the materials, the contribute that Archaeometry and Conservation Science, can give to the knowledge and preservation of earthen architecture concerns the possibility to get information on the

Institute for the Conservation and Enchancement of Cultural Heritage, CNR, Italy

Fig. 33: The archaeometrical study as a part of the analysis and modelling of a tacit local knowledge system.

provenance of the raw material, possible mixing of two different earths and additives, kneading methods, amount of water in the mixture). The material of the earthen architectures Earthen architectures are realised with a material, the earth, which has a pseudo-coherent consistency, constituted by a prevailing mineral component and an organic fraction composed of vegetal residues. The former is has a fine granulometry fraction mainly composed of clay minerals (which have dimensions < 4 mm) and a coarse granulometry fraction (silt, sand and gravel fractions) composed of rock fragments and non-argillaceous minerals. The composition (amount and type of clay minerals and amount of coarse fraction) determines the behaviour of the earth, namely its plasticity, shrinkage, workability, mechanical characteristics and durability of the artefacts.

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Archaeometrical analysis of earthen architectural materials

Fabio Fratini

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Plasticity Plasticity, in particular, is a peculiarity of the clay materials manifested when the material absorbs water and disappears when the water is lost. This behaviour is due to the lubricant and binding action of the absorbed water that creates a liquid film around each clay particle. Each kind of clay is characterised by a well-defined range of water content in which a plastic behaviour is exhibited. Below that water content the material displays an â&#x20AC;&#x2DC;earthyâ&#x20AC;&#x2122; character because there is not enough water to completely coat the clay particles, while with a higher amount of water the material becomes fluid because the clay particles are too far from each other to be able to interact. Because of this characteristic to be plastic above a certain water content but stiff below that water content, as previously reported, clays and earths are considered pseudo-coherent materials and they can be distinguished in the following two categories: lean earths - constituted by a high % of clay minerals; - retaining a high amount of water and losing it slowly through evaporation; - suffering major shrinkage during drying; - displaying high plasticity. fat earths - having a strong content of coarse fraction constituted by non-argillaceous minerals; - retaining a minimal amount of water and losing it easily; - displaying low shrinkage during drying; - displaying low plasticity. Mechanical characteristics Regarding the mechanical characteristics and durability of the artefacts made with earth, fat earths give a high cohesion to the dry product but problems arise due to the development of strong shrinkage fissuring. Therefore, in order to have good mechanical characteristics of the dried product, a quantity of clay minerals to confer good cohesion (hence a low intergranular porosity) is necessary, though not too much to prevent the development of cracks during shrinkage. Regarding the characteristics of plasticity and the development of cracking during drying, considerable influence is also played by the type of clay minerals, in fact the presence of swelling clay minerals

Fig. 34: Example XRD spectrum of a mineral.

such as smectite and vermiculite may increase the shrinkage with very pronounced cracking and worsening of the mechanical properties. From what has been reported, it is easy to understand the importance of knowing the mineralogical composition of the artefacts in order to understand their conditions of conservation. In the following, the methods used in the archaeometric study of the earth materials are reported, referring particularly to the determination of the mineralogical composition. Further investigations not strictly archaeometric are those involving the study of physical characteristics (plasticity) and granulometry. The mineralogical composition The study of the mineralogical composition is made by X-ray diffraction, a method of analysis that permits the recognition of the phases with crystalline structure in a material. The principle of the method is based on the fact that each crystalline substance is formed by a structure defined by an ordered lattice (crystal lattice), which is characterized by families of reticular planes with special reticular inter-planar distance (d). The analysis proceeds as follows: - the sample is hit by an X-ray beam of defined wavelength (l) with a hit angle (q) variable during the analysis; - each time the Bragg law (nl=2dsenq) is satisfied, a reflection of X-rays is produced that is recorded. Each mineral is characterized by a well-defined sequence of reflections, caused by several families of planes, that is possible to recognize (Fig. 34). Therefore, it is possible to determine the so-called principal mineralogical composition and the composition of clay minerals. The former concerns particularly the minerals of the coarse fraction and is determined on the powdered sample. The most common minerals present in this fraction are quartz, feldspars, calcite and dolomite. The analytical data of the principal minera-

Fig. 35: Ternary diagram TCF: T = tectosilicates, [quartz, feldspates]; C = carbonates; F = fillosilicates [clay minerals].

layers sequence

distance between the basal planes (Å) not treated

ethylene glicol

450°C

600°C

caolinite

7-7.2

illite

TOT

chlorite

TOT+O

13.5-14

smectite

TOT

14.5-15

vermiculite

TOT

14.5

illite-smectite

12.5-13

13-13.5

chlorite-vermiculite

14.5-15

11.5-12.5

Clay minerals: reticular distances of the basal planes as a function of various treatments.

Calcium carbonate content The quantitative analysis of CaCO3 is normally performed through a calcimeter. The volume of CO2 developed during the reaction between hydrochloric acid and calcium carbonate is measured. Such a method can be applied only in absence of dolomite because this mineral participates to the reaction, though at a slower rate, and therefore it cannot be distinguished from calcite.

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logical composition (a semi-quantitative estimate for routine analysis) can be represented in a ternary diagram TCF (Fig. 35). The clay minerals are studied on ‘enriched’ samples obtained by removal from the starting material the granulometric fraction > 4 mm (Fig. 39). The samples are ‘oriented’, so that the clay minerals lie on the holder oriented according to the planes of the basal lattice (Fig. 37). This is because these minerals are characterized by a differing distance between the planes of the basal lattice and allows better investigation of this aspect also as a result of heat treatment and the absorption of substances like ethylene glycol (Fig. 39).

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Fig. 36: Process of enrichment in clay minerals through sedimentation. Fig. 37: Preparation of an ‘oriented sample’ in order to study the clay minerals through X ray diffraction.

Organic substance content The content in organic substance can be determined gravimetrically through hydrogen peroxide attack. The reaction causes the disruption of the organic substance with development of CO2 (volatile) and H2O. After the attack, the sample is dried at 60 °C to a constant weight. The weight loss expressed in % respect to the initial weight can be attributed to the % of organic substance. Fig. 38: XRD spectra of smectite, untreated (blue) and treated with ethylene glycol (red). It is possible to observe the expansion of the crystal lattice of the treated smectite.

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AN ARCHITECTURAL CULTURAL LANDSCAPE

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When Neolithic man first began to comprehend how to interact with and use nature, developing a process of domestication of spaces and habitats, the forming of human culture began. Hunter-gatherers embarked upon a process of appropriating natural spaces, progressing from the linear and temporary to the central and permanent, defining the fundamental necessities of a site for permanent settlement relevant to this day, and which in the arid or semi-arid regions are met with difficulty, above all, the particular necessity of water. The need to adapt to arid conditions, to scarce energy supplies, and the difficulties of satisfying the parameters of hygrothermal comfort, has determined the development of a technical culture of resource management, not only of agriculture and stockbreeding, but also of settlement and construction. The region southeast of Aleppo The region which has developed to the south and east of Aleppo, from the Euphrates to Salamiya, has been inhabited since Neolithic times by settlements of sedentary and nomadic peoples. Archaeological investigations have brought to light and identified hundreds of sites. The few most ancient sedentary farming populations have been identified from the Neolithic Pre-ceramic B period (9600-8000 BC), with populations settling near readily available water resources and corresponding to a climatically favourable period. In the Chalcolithic period (6000-3700 BC) there are traces of sedentary settlements, despite unchanged soil and climatic conditions, though this may be due to the difficulty of identifying the ceramics of that period. In the Fertile Crescent, the Neolithic period saw the development of agriculture and stockbreeding. The arid lands of Syria and the Aleppo region were quickly inhabited and became an area of contact, exchange and con-

University of Florence, Italy

flict between the nomads and settled populations that represented two distinct ways of life and two antagonistic ways of using the land, two different cultures, that of the sedentary farmers and that of the nomadic stockbreeders, alternatively dominating this region, and each coming to terms with the demands of the environment in their own particular ways. A heritage of exceptional value. The main interest for a study of domed habitats in northern Syria is closely linked to this exceptional fluctuating culture of uncertainty. Throughout the centuries not only have sedentary peoples substituted nomadic tribes, but the populations have fluctuated between the two lifestyles, often integrating into and present in the same communities or even the same families.

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An architectural culture of uncertainty

Saverio Mecca

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The various peoples who have lived in these regions down the ages have had to restrict their living and develop strategies to deal with climatic uncertainties, and chiefly with the supply and availability of clean drinking water. The arid climate has dominated the character of this region for millennia, a determining factor as regards settlement, architecture, building culture, use of land and various resources in relation to different kinds of topology, hydrology and geomorphology. Interaction with the environment in uncertainty Primarily, it is in the interaction with the natural world, the social and the political, in the capacity to adapt and maintain systems of settlement, that we can find the value and interest of this heritage on a global scale: the domed architecture, its form, the construction technique with its variations and adaptations, and the organisation of the houses and villages, reflect both ways of life, the two cultures of the nomad and the sedentary. The climate, in particular regarding the fluctuating presence of clean water over time, has influenced the expansion or contraction of these ways of life in relation to the capacity to adapt to or mitigate adverse climatic and natural conditions. A present closer to the distant past Secondly, the strategies and solutions of settlement, and the use of resources observed today, are similar to those developed in past millennia, reflecting a situation of continuity even through the vicissitudes of both natural and social conditions. Despite the difficulty of reconstructing in detail the history of these places and populations, often reusing as they have places, materials and structures, the technical cultures that gave form to the settlements of the territory transmit today antique signs of the relationship between the nomad and the settled, between rural populations and urban powers, between the forces of nature and an uncertain climate, technical cultures and social practicalities. Since Neolithic times, such factors have marked out these borderlands, through oscillations between crisis, abandonment, growth and development. A culture of uncertainty Thirdly, there is the architectural expression of a culture of uncertainty in relation to the environment. The specific object of the Culture 2000 project is to contribute to the general awareness of this heritage and, in

particular, to bring to light the value of architecture as an intense and permanent expression of local and indigenous systems of knowledge, together with the strategies activated to manage the relationship between man and his environment. This catalogue documents, and goes some way to conserving, a mobile culture on the border between the settled and the nomadic, a culture of uncertainty that finds in its essence the potential capacity of flexibility, of adaptation to the unforeseen mutability of nature, of passing from the sedentary to the nomadic when social and natural conditions dictate. The regular availability of drinking water. The agricultural development of the arid zones finds its own equilibrium over time between the cycle of cultivation and the distribution and quantity of rainwater. Farmers and stockbreeders, however, need daily supplies of clean water, particularly in the hottest seasons. The localisation of water and its supply points are determining factors for the site of a settlement, whether permanent, seasonal or temporary. In arid climes, springs can be few and far between. Nowadays, natural springs are limited in number in the region, rivers and streams are slow flowing, particularly in summer, and are often further weakened through drawing off by centres of population or irrigation. Among the techniques used in the region to distribute water for agricultural and stockbreeding purposes are: - The birkĂŠ, a simple hollow with a base made impermeable by clay to collect rainwater. Mostly found towards the coast, but also further eastwards inland towards the Wadi Abu Hawadid, associated with stockbreeding activities. - Rainwater cisterns, excavated into rock and under less compact strata, rectangular or pear-shaped, with stone walls in the upper part and fed by surface water. - Small dams, of which only two examples are known.1 - The hydraulic infrastructure, which is the major characteristic of the region, is the quanat, or underground drainage tunnel. The longest are in the region south of Lake Jabboul, towards La Fayda, the central clayey 1

Jaubert, R. & Geyer, B. 2006. pag. 42

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A basic constructive strategy: the spiral The spiral is the most ancient symbol found on every civilized continent, most likely representing the cycle of “birth-death-rebirth”, or symbolizing the continuous cycle of the sun. The spiral archetype has always been part of our natural and man-made landscapes: in the natural world spiral seashells have fascinated us for thousands of years, man has always gathered spiral-shaped objects and waded through spiral eddies and whirlpools, or seen similar patterns while making cheese in the pot. The ability to carve spiral shapes on rocks expresses the process of appropriating and managing the concept of the spiral, which has been identified as a powerful structure of nature in a positive but also negative and destructive way. In traditional cultures there was no separation between function, shape, symbol and relation to nature: so the spiral dynamic form is the core of many processes invented to shape nature: spirals are at the heart of basket weaving and pottery making, and also central to the concept of raising an edifice. Basket weaving is a widespread craft in any human civilization: the oldest known baskets are (according to radiocarbon dating) between 10,000 and 12,000 years old, earlier than any archaeological ceramic finds. Pottery making is one of humankind’s first inventions and better conserved because of the durability of fired clay. The earliest known pottery dates to about 10000 BC in parts of Asia with other evidence from the Middle East dating to about 6000 BC. Corbelled dome construction follows the same strategy of shaping and adapting nature to human needs, imitating and respecting natural pat-

terns and structures. As for weaving baskets a continuous building pattern can progressively produce a new ‘natural’ shell adapted to basic human needs, and also on a greater scale, can generate the tallest of buildings as a veritable bridge to the heavens. Living in the arid margins The habitats under study are situated principally in a region crossed by the 200 mm isohyet, which marks the border of the steppe lying to the east of the line (classification by the Ministry of Agriculture of the Syrian Arab Republic). The diversity of habitats in relation to the uses of the land for agriculture and stockbreeding are linked to the aridity of the area, or rather, to two principal differentiating factors: the climate and the soil. The different factors constituted by the climate, orography, hydrology, pedology and soil, in combination and interaction with the available water resources, all come together to determine a great variety of habitats. Corresponding to the variety of habitats, a great homogeneity exists in the temporal continuation of architectonic and constructional strategies that determines a highly individual panorama of earthen settlements and architecture. The homogeneity and continuity down the millennia is based on a capacity to adapt to the natural materials available: clay, earth, limestone, basalt, and materials recovered from previous settlements, notably villages of the Byzantine era, and to the identifiable construction techniques from these settlements. The characteristic of cultural plasticity2 of earthen architecture finds in the lands of the arid margins one of its most explicit affirmations. For agriculture and stockbreeding, even slight changes in climate and soil, in orography and water supply, demand the development of fresh cultures and strategies. Indeed, an immense cultural capacity to adapt and change is required, one that induces a behaviour characteristic of nomadic populations, that of mobility, flexibility, and reversibility, the capacity to pass from the sedentary to the nomadic lifestyle, depending on social or physical conditions, for the ultimate survival of the group. For architecture and settlements a different, inverse strategy develops, ‘Earth’ offers a great capacity to respond to the housing needs of millions of human beings, not only quantitative needs compatible with limited environmental harmony and resources, but also qualitative cultural requirements, as a result of its high cultural ‘plasticity’, its ability to change and adapt in response to changes in the natural and human environment, and to be an expressive language of identities and differing histories.

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lemon plains (Al-Andarin), while others are found on the chalky levels, fed by the water table or artesian springs. There are some longer, constituting real and proper canals that terminate in distributing basins, and shorter examples destined for more local usage. They were utilised for the supply of water for both domestic usage and irrigation. - Finally, wells positioned at the height of the water table. The variety and thoroughness of the technical culture for the production and conservation of clean water testifies to the importance of this factor, explaining the localisation and permanence of the settlements over time.

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predisposed to reproducing or adapting its constructional and architectural culture under diverse conditions. The sensitivity to climatic and social factors is in some way altered, on a larger geographical and temporal scale, stronger on a symbolic level for the conservation of a nomadic vision of their relationship to the environment. Apart from stone materials, the presence of cultivatable land usually coincides with the presence of construction materials, such as clay and sand. To sum up, the conditions of settlement are: - the availability of cultivatable earth with the presence of soil suitable for sowing; - a level of rainfall or water supply sufficient for the growth to maturity of certain species of plant, and the availability of clean water; - the availability of easily utilised construction materials, with an experienced constructional culture, accessible to the family group; - A basic constructive thinking for generating three-dimensional objects such as corbelled spiral domes. On the whole, the aridity of the climate constitutes an overriding influence, not only over agro-pastoral production, but also over the production of habitable settlements and the transformation of the territory by populations occurring in the region. Beyond Architecture Architecture can give shape to the invisible pulses and rhythms of life, expressing the ‘magic’ power that is present in all elements of nature. Architecture is a process which gives sense and structure, organizes and composes in a systemic way different interrelated energies into a material and cultural whole. The physical manifestation of architecture is always an expression of tension, taking what is invisible and immaterial and making it visible and human. This tension we may perceive in the domes of Syrian villages, and in the dry-stone domes of all Mediterranean regions.

List of References Bocco, R., Jaubert, R. & Metral, F. (eds) 1993, Steppes d’Arabies. Etats, pasteurs, agriculteurs et commerçants: le devenir des zones sèches, Presses Universitaires de France, Paris, et collection Cahiers de l’IUED n°23, Genève, pp. 403. Geyer, B. & Jaubert, R. (eds) 2006, Les marges arides du Croissant fertile: peuplement, exploitation et contrôle des ressources en Syrie du nord, Maison de l’Orient et de la Méditerranée, Lyon.

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Institute FranĂ§aise du Proche-Orient, Damascus, Syria

Syriaâ&#x20AC;&#x2122;s position on the eastern side of the Mediterranean gives it a complex natural context that is characterized by a tendency to change rapidly from an area of high rainfall to arid steppe, turning to desert during the dry years. The country possesses a modest littoral border onto the Mediterranean Sea with 183 km of coasts and a surface area of 185,180 square km. It boasts a considerable population for a country dominated by a semi-arid Mediterranean climate, and more than half its territory is occupied by steppe (55%). According to the last census of 2004, Syria had a population of 18 million (c. 21 million at present). The main cities are in the west part of the country: Damascus, Aleppo, Homs, Hama and the main port of the country, Lattakia (Fig. 1). Syrian territory is dominated by the coastal mountains, leaving little space for the narrow plain (Fig. 1). This modest and inhospitable massif (Nabi Younes rising to 1,568 meters) holds little potential for economic activity. The coastal mountains present a real obstacle for precipitations coming from the west as well as for maritime influences. In a journey of about 100 km eastward, the yearly precipitations range from 1,000 mm on the coast to 200 mm in the interior, from the perpetual snow on the summits of Hermon to the oasis of Palmyra and the steppes of the inner parts of the country. The Homs Gap, between the Syrian coastal mountains and the Mount of Lebanon, allows maritime influences to penetrate towards the interior, which shifts the precipitation isohyets (Fig. 1) eastward, so watering the vast areas of cereal agriculture on the high plains of Central Syria. Beyond the coastal mountains and the chalk mountains of the west, a vast tableland of steppe slopes towards the east and cedes progressively to stony desert: the desert of Djezirah to the north and the desert of Chamiya to the south.

The Region of Aleppo On the plains of the region of Aleppo rise two small basaltic tablelands, known locally as Djebel. They are covered with lava, giving them a prominence that breaks somewhat the monotony of the inland countryside (HamidĂŠ 1959, 65). These are the tablelands of al Hasse, with an altitude of more than 600 m in places, and the Chbeit toward the southeast of no more than 500 m. They are separated by the plain (or couloirs) of Khanasser. The two rise more than 100 m above the salt marshes of Jabboul and their surfaces are covered with basaltic boulders and stones, resulting from the disintegraFig. 1: Map of Syria with the study area

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A geographical analysis: the regions of Aleppo and Central Syria

Mohamed Al Dbiyat

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Fig. 2: Settlement phases in Syria

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tion and decomposition of lavas, and are furrowed by the valleys that form the present hydrographic network. The earth in general is difficult to plow with the exception of the alluvial pans. However, impressive works of stone removing have permitted the planning of important arable spaces mainly for rainfed barley. This is the ideal culture for sheep breeders who have lately populated the region (cf. below). Here livestock is limited to the fallows, to post-harvest or, during the dry years, unripened fields, and to uncultivable lands. Some management of the area goes back to more ancient times, notably to the Byzantine period. One finds traces of the vestiges of this time everywhere in the two tablelands, and also on the plain of Khanasser that separates them. Remains can be found of hydraulic works, notably the qanat (underground gallery), called locally: qanat romaniyah. These ensured food for the city of Khanasser through means of irrigation. They are currently dry, mainly due to the intensification of wells on the plain in the 1950s and to the effects of a long period of drought that Syria experienced between 1955 and 1960. Also in the tableland appear, besides the elevations already mentioned,

closed depressions of which the most significant in the region of Aleppo is the sebkha of Jabboul (308-315 m altitude) occupying an inconstant surface area, considering the seasonal water of the valleys, which can reach up to 150 square km. It is also an important salt marsh, producing about 10,000 tons of salt per year, so ensuring the survival of the neighboring populations, such as the villages of Oum Aamoud Kebir and Oum Aamoud Seghirs. The other sebkha to the south of Djebel Chbeit is the lesser sebkha of Moragha (340m). To the south of the tableland of al Hasse spreads the sebkha of al KharaĂŻj, while to the west one finds the sebkha of al Matkh into which the river of Koueik empties. All these areas are barren as regards agriculture and livestock. To the north of our study area and to the west of the region of Aleppo, spreads an important plain that has benefited since the end of the 1980s from the large planning project of Maskaneh-west. It is the zone of cotton cultivation with an irrigation system relying on water from the dam of Assad on the Euphrates. The most significant sector is that of the Sfireh, the largest city to the west of Aleppo before those of the Euphrates valley. This scheme is a recent extension of the Maskaneh-west project and was inaugurated in 2008. It covers about 65,000 ha. Central Syria The zone of study in Central Syria is in the eastern part of the region where the village of Sheikh Hilal is located. It is the most arid part with a precipitation ranging between 200 and 250 mm per year. The relief is, in general, markedly flat with a certain featurelessness on the plains that characterizes the tableland of the Syrian interior, though here and there a second level of tablelands in the form of hills occurs with an altitude of between 400 and 500 m. To the south of this zone the mountain of Balâ&#x20AC;&#x2122;as rises to c. 1000 m. This is the western part of the Palmyrian Chain of mountains of the north. There is higher rainfall due to the altitude, where precipitations can reach 300 mm per year, allowing a denser plant cover with scattered centennial trees, mainly wild pistachios (Pistacia Lentiscus). Northbound from this mountain stretch the main valleys that are part of the endorheic basin, with its center towards the south of the region of Aleppo in the territory of the ancient Byzantine city of Andarine (the antique Andarona). The village of Sheikh Hilal is located on the high plain to the north side of the mountain of Balâ&#x20AC;&#x2122;as in a small depression

Fig. 3: Dromedaries in the steppe at south of Khanasser 189

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Earthen Domes and Habitats Fig. 4: The road near Cheikh Hilal village Fig. 5: Fields near Cheikh Hilal village

with quite significant potential in its ground water table. It is this resource that permitted irrigated agriculture in the village, through the qanats, and later with motorized pumps from wells. The climate As for the climate, it is Mediterranean to the north and on the coastal plain. The rainfall assures good vegetation and the slopes are covered with forests of pines and cedars and also olive groves.

Further inside the country the climate becomes continental: hot and dry in summer (up to 42Â° C), cold from December to March. The climate is marked by one long season without precipitation that continues for about 5 months, from May to September. This type of continental Mediterranean climate transforms the steppes into desolate plains during the dry period. In theory this land is reserved for grazing but, since the 1990s, a state-controlled project of development for the steppe has resulted in the replacement of the natural vegetation with fodder crops. The arid margins correspond to a strip of land to the east and the west of the 200 mm isohyet, at the limits of the steppe, and this is our study area (Fig. 1). The width of the arid margins can be estimated as 50 km west to east in Central Syria and north to south in the region of Djezirah. But it is a mobile area linked to precipitations, due to the mobile line of 200 mm. In years of higher rainfall, it advances further east, while moving back westward in arid years. Population density is closely linked to the climatic conditions and to the industrial zone of Syria. The highest population density and superior to 150/square km is in the west and in the cities, while in the steppe it descends to less than 5/square km. The Syrian territory is divided in two parts, the Mâ&#x20AC;&#x2122;amoura and the Badia. The former is reserved for the non-nomadic, the cities and farming villages, the Fertile Crescent. The latter is the land of the Bedouin tribes who practice the nomadic style of life, though about twenty years ago this started to become a place of winter transhumance for big non-nomadic and semi-nomadic livestock farmers from the arid margins area. Since the nineteenth century the arid margins of the Djezirah, including the course of the Euphrates, have again become new territories of the Ottoman population and settlers. Economic development politics have aimed to expand agricultural estates and to control the nomadic tribes seen as threatening the security of trade routes and agricultural lands in the Mâ&#x20AC;&#x2122;amoura (Fig. 2). In these arid margins one finds a mosaic population of varied communal or ethnic origins. All came in search of improved economic opportunities compared to their regions of origin, notably those coming from the coastal mountains: Ismailis, Alawites and Christian, the Kurdish or Circassian refugees, or tribal nomads. All wished for a slice of the distribution of the state lands by the Ottoman authorities, who encouraged them to

The character of settlements in the arid margin areas The arid margins of the Fertile Crescent are characterized alternately by two lifestyles, nomadic and settled, which for about ten millenniums have dominated alternately, according to climatic and demographic variations, the vicissitudes of history or technological progress. The region of study experienced several phases of expansion of the cultivated estate, of agricultural colonization of the steppe, demographic growth and relative economic prosperity. These periods have been followed by phases of decline, of receding agriculture, of abandonment of villages and re-appropriation of lands by nomadic tribes. The Mongol invasions in the fourteenth century repulsed westward the settled populations of the arid margins. Travelers who crossed the Syrian steppes during the eighteenth and nineteenth centuries testified to the general abandonment of the villages after ravaging by nomadic tribes. In the middle of the nineteenth century, when the movement of re-occupation commenced, seen now in contemporary villages of the arid Margins, the western limit of the Badia was located on the Homs-Aleppo axis. The movement of re-colonization was initiated and sustained by the Ottoman administration, in a double goal to strengthen sovereignty over the western parts of the empire and to spread cereal agriculture eastward, in order to increase agricultural production. This politics of settlement was instigated by the Sultan Abdul Magid (1839-1861), who was concerned about protecting the Mâ&#x20AC;&#x2122;amoura, the lands of settled farmers and villages, subject to incursions by Bedouin tribes. To encourage populations of different origins to settle in the arable areas of the steppe, the Ottoman authorities gave political incentives such as exemption from military service and a system of reduced taxes. State police stations were created to ensure the security of the new occupants, authorized to detain weapons and to raise defense militias.

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settle and to practice the agriculture of rainfed barley in the arid margins. What is interesting in this diagram is the lifestyle of each community or ethnic group, and also the type of habitation that interests us in this work. In general, dwellings are in earth, but the forms differ from region to region or from one community to another. These constructions are suited to the arid environment as well as to the means of poorer inhabitants well-adapted to the uncertain climate.

Fig. 6: Olive tree near Cheikh Hilal village

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Earthen Domes and Habitats Fig. 7: A view of Cheikh Hilal village

The process of re-occupation by non-nomadic populations or semi-nomadic was not however uniform. Sensitive differences over matters of population and fundamental structure can be observed between the villages of the arid margins in the provinces of Hama and Aleppo. These differences generally go back to the origins of the contemporary villages. The repopulation of the region of Homs and Hama in Central Syria The farming population of the region of Salamya has mainly come from the west, notably Ismailis and Alawites, and from the Bedouin members of local nomadic tribes, or from the east of the country. Typically, the process of occupation of the region of Salamya to the east of Hama saw the creation of points of colonization, of mother villages, from which new agricultural villages were then established. Some attempts at implantation failed at first due to pressure from nomadic tribes. These abandoned sites were subsequently reoccupied. Though the Ismailis were the most numerous, they were not the only farmers to settle in the region. Alawites, originally from the same inshore region as the Ismailis, participated in the process of agricultural coloniza-

tion of the region of Salamya, as did Circassian refugees. The descendants of the latter populate several villages currently in the western part of Central Syria, to the north of Salamya and north east of Homs. The settlement of the Circassians and the Alawites is on the same diagram as the Ismailis. The first villages created by these two agricultural communities were built on archaeological sites, where arable lands were once irrigated with qanats. The spatial distribution of villages of Ismailis farmers, Alawites and Circassians in Central Syria is bound closely to agricultural potential and to the presence of ancient hydraulic works. This explains the agricultural re-occupation process of dwellings between which spread large expanses of steppe, occupied subsequently by semi-nomadic Bedouins. That most important of resources, water, was provided incontestably by the networks of qanats distributed across the region. Numerous depressions or plains have been irrigated using the waters of these qanats, restored then by pioneering populations. The most extensive plain was the Salamya plain, which had a significant network of irrigation fed by three main qanats. However, the spread of individual pumping since the 1950s dried the qanats quickly before exhausting the stock accumulated in the superficial water sheets. Many wells dried up and the once irrigated plain has seen the abandonment of numerous farms.

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The settlement of nomads The settlement of the Bedouin tribes to the east of the Orontes River, from 1871 onwards, followed the application by Subhi Pasha, the Wali of Damascus, of an active politics of settlement of the nomads. This aimed to reinforce control of the nomadic populations and to increase the production of cereals for the provision of the empire. The settlement was, nevertheless, partial; most nomadic families who were settled in the region kept up the activity of transhumance, classifying them in the category of semi-nomads. The best land, notably the irrigable surfaces, were occupied by farmers come from the west. The lands on which the Bedouins were settled only allowed rainfed cereals of uncertain yield. Otherwise, this partial settlement served the interests of the political authorities anxious to preserve the pastoral economy for the production of meat whilst reinforcing its control over the arid Margins. The movement of settlement intensified under the reign of Sultan Abdul Hamid II, 1876-1908, (Fig. 2). The Sultan appropriated a million hectares to the east of Homs and Hama in the state lands. “He provided security in this vast private estate. He exempted the tenants from military service, protected them against the aggression of the nobles and granted them credit without interest; so these zones were inhabited after having been constantly ravaged by the Bedouin” (Kurd Ali 1926, p. 214).

The chiefs of the tribes held control of the mousha lands (lands of common property) and decided upon distribution among the tribe’s members. The rights of use were sold by the tribal chiefs, which continued to be the custom in the big latifundium properties of Central Syria until the application of the agrarian reforms of the 1960s. The resettlement of the region of Aleppo The process of reoccupation of the north of our study area is appreciably different from that which can be observed in the region of Salamya or to the east of Homs in Central Syria. There are several reasons for this. Compared to the arid margins of Central Syria, underground water resources are less abundant and ancient hydraulic management less common. For this reason the region was less attractive for farmers. The best lands, suitable for the production of wheat and lentils in pluvial conditions, situated on the tableland of the Djabel al Hass, belonged to the Sultan’s estate, and were not monopolized by urban owners as was the case in the Djabel al Ala, where the agronomic features are comparable. With the exception of the village of Khanasser, established on the site of the antique Anasartha, populated by Circassians in 1907, the population of the arid margins of the province of Aleppo is of Bedouin origin. The movement of settlement in this region started at the end of the 1840s and intensified following

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a military campaign led by the Wali of Aleppo against the raids of the region’s Bedouin tribes. These last submitted to the Ottoman authority in 1868. The installation of Bedouin families, mainly from the Malawi tribes and Hadidiyns, was encouraged on the Sultan’s lands from 1876 by incentive measures such as the supply of agricultural tools and a reduced taxation scheme (Fig. 2). For a long time the village of Khanasser remained the only agricultural implantation in the east of the Djabal al Hass. The lands of the Djabal Chbeit and a part of the valley were assigned in 1870 by the Wali of Aleppo to the Sheik of the powerful tribe of the Fed’anses. The agricultural exploitation of his lands began in the 1930s. Crops were sown by Bedouin sharecroppers of the Sheik of the Fed’anses who claimed 50% of the production of grains. The exploitation of the lands remained extensive until the beginning of the 1960s. Tractors were used for the first time in 1963, permitting farming over the entire arable surface of the region. This intensification followed the drought of the years 1955-1960 which led to the almost total disappearance of the herds and to the agrarian reform that freed the sharecroppers. Conclusion The reoccupation of the arid Margins of the provinces of Aleppo and Central Syria (Hims and Hama) operated in a notably different way. More abundant water resources attracted farming populations to the province of Hama, mainly Ismailis, from the coastal mountains. The less favorable spaces permitting only pluvial agriculture were essentially occupied by Bedouin families. In the case of the villages of the province of Aleppo, only the village of Khanasser was inhabited by isolated farmers in a population of Bedouin origin depending extensively until the 1960s on livestock transhumance. In general, the agricultural villages possess a denser urban structure than the villages of the agro-pastors or the semi-nomadic pastors. This is the case in the Sheik Hilal village that is occupied by Ismaili farmers, or Khannassers with its Circassians farmers. Significantly, the earthen houses in these regions are closely correlated to the economic situation. The houses are generally modest both on the outside and inside, with the exception of the landowner’s rather more noteworthy dwelling, often built in stone.

The people of the arid margins, especially the non-nomadic, are more or less directly subject to the difficulties of climatic aridity. Thus, these regions are marked by the mobility of their populations, a mobility especially linked to the very difficult economic conditions, notably: the poorness of soils, low rainfall and the scarcity or modest quality of public services. The effect of this mobility of inhabitants on the habitat is clear. Either the abandoned dwellings are in a ruined state, as in the village of Sheik Hilal, or new houses are constructed in cement financed by emigration. In the region of Sfireh, with its new project of irrigation from the waters of the Euphrates, one notes a certain stability of the populace in relation to the development of irrigated agriculture, notably cotton. This is the case of the villages in the surroundings of Sfireh, such as the village of Qobtaine. List of References Ababsa, M. 2004, Idéologies et territoires dans un front pionnier: Raqqa et le Projet de l’Euphrate en Jazîra syrienne, doctorat de Géographie de l’Université de Tours, pp. 560. Al- Dbiyat, M. 1980, Salamiya et sa région, Thèse de 3ème cycle, Université de Tours, pp. 300. Al-Dbiyat, M. 1995, Homs et Hama en Syrie centrale. Concurrence urbaine et développement régional, IFEAD, Damas, pp. 370. Al-Dbiyat, M. & Jaubert, R. 2006, ‘Le repeuplement sédentaire des marges arides à l’époque contemporaine (1948-1960)’, Geyer, B. & Jaubert, R. (eds) (eds), Les marges arides du Croissant fertile: peuplement, exploitation et contrôle des ressources en Syrie du nord, Maison de l’Orient et de la Méditerranée, Lyon, pp. 71-80. Amine, M. 1982, Salamiya durant cinquante siècles, Salamiya, pp. 390. Douwes, D. & Lewis, N. 1992, ‘Taxation and Agricultures in the District of Hama, 1800-1831. New material from the records of the religious court’, Philpp Th. (ed.), The Syrian land in the 18th and 19th Century, Berliner Islamstudien, Bd. 5, FranzSteiner Verlag, Stuttgart, pp. 261-284. Gathier, P.-L. 2000, ‘Une frontière sans limites’, Nordiguian, L. & Salles J.F., Aux origines de l’Archéologie aériennes, Presses de l’Université Saint Joseph, Beyrouth. Geyer, B. & Jaubert, R. (eds) 2006, Les marges arides du Croissant fertile: peuplement, exploitation et contrôle des ressources en Syrie du nord, Maison de l’Orient et de la Méditerranée, Lyon. Hamidé, A.-R. 1959, La région d’Alep, Etude de géographie rurale, thèse d’Etat, Université de Paris. Hazoury, J. 1984, L’habitat en terre, Direction des travaux militaire, Alep. (en arabe). Kurd Ali, M. 1926, Les plans d’Al Cham, vol. 4, Beyrouth. Lewis, N. 1987, Nomads and settlers in Syria and Jordan, 1800-1980, Cambridge University Press, London, pp. 223.

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The traditional architecture of western Syria1 has not yet been the object of a general summary, and the few available studies tell us about some elements of architectural types or buildings in earth and in stone. R. Thoumin attempted at the time of mandate to publish an analysis on the architecture of Damascus and the region of Qalamoun with the aim of presenting a first overview on the relationship between the architectural types and the different geographical features of central Syria. There are several publications on this matter, but without a global view.2 Gh. Al-Jundi has provided, in collaboration with UNESCO, a first synthesis combining a rich architectural documentation on Syria with plans, sections and photographs.3 Önhan Tunca, as part of an exhibition, with a team of the Belgian Mission, brought together documentation provided on the northern extremes of Syria around Sabkhat el-Jabboul. The purpose of this study was to provide a clear vision of the site of Umm el-Marra.4 K. Putt presented in a widely documented book a comprehensive overview on traditional architecture in Syria with a typology after several field missions.5 Finally, Mahmoud Bendakir has recently published a study of architecture with numerous illustrations and sometimes detailed documentation (graphic and photographic).6 Overview of the region The region chosen here is at the western edge of the Syrian steppe in an area relatively rich in water resources and agriculture. The average rainfall never exceeds 200 mm, which hardly allows for profitable agriculture. However,

For the development of domestic architecture in Syria from the Neolithic era to the Arab-Islamic period see: Aurenche 1981 and Castel, Al-Maqdissi & Villeneuve (eds) 1997. 2 See: Thoumin 1933. 3 See: Al-Jundi 1984. 4 See: Tunca, Meunier, Lamisse & Stockeyr 1991. 5 See: Pütt 2005. 6 See: Bendakir 2008. 1

Directorate General of Antiquities and Museums, Damascus, Syria

water management systems, renowned since ancient times, encouraged the cultivation of land and settlement. The available archaeological documentation reveals a complex situation characterized by several phases of development.7 The first major development in this region must go back to 2,600 bc to the time of the second urban revolution in the Middle East. This first mass settlement left important remains in the study area, particularly in cities8. At the beginning of the second millennium, a further phase begins with the arrival of the Amorites, leading to the creation of the city of Qatna and communication routes connecting the Mediterranean coast to the valley of the Euphrates. The third development phase occurs after the settlement of the Aramaeans towards the ninth century bc, which sets up the conditions capable of promoting economic progress in the kingdoms of Hama and Aram. The takeover by the neo-Assyrian empire in this region then tails off and it is not until the arrival of Alexander the Great in 333 bc that the region experiences one of its most brilliant periods. Its development is to focus directly on the Orontes at the sites of Aréthuse (Hellenistic period) and Emes (RomanSee in this regard: al-Dbiyat 1995. See for the documentation for Mishirfeh and its region, Al-Maqdissi 20081, pp. 3-41; Al-Maqdissi 20082, pp. 5-10 and Al-Maqdissi 2009.

7 8

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Domestic earthen dome architecture of Central Syria

Michel al-Maqdissi Antoine Suleiman Fadia Abou Sekeh

Byzantine era). The western edge of the steppe sees a situation characterized by intense agricultural activity and the foundation of several cities under the control of the two capitals. This situation continues until the Islamic period (Mamluk).9 During the twentieth century, movements of populations from the mountains and the steppe have resulted in new settlements with favourable economic conditions and renewed agricultural possibilities. This migration, which dates from the time of the French Mandate and the first decades of independence, has had positive consequences for the use and maintenance of traditional earthen architecture. This was interrupted by the economic boom, during which modern materials have gradually replaced earthen, thus serving to justify our approach and our intention to save what remains of this heritage before it disappears entirely.

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Hama

Salamiyeh Bural Sharqi

Buwaidetl’ Mkharam Tahtani

Rihaniyey

Foqani

Mishrfeh Mkharram Homs

Al Hraki Tal Shnan As’Sayed

Al Fruqlos

Ar’Raqama Holayeh Ash’eirat

Qnayyeh

Khirbet Ar’Rdefat Hasya

Sadad Ar’Rhebeh Al Breij

Hawarin Mahien

Fig. 1: Map of the distribution of identified villages in Central Syria region

Al Qaryatein

The material presented The body of material focuses on domed buildings identified in 17 villages at the western edge of the Syrian steppe (Badiyat al-Sham) according to the following list: - El-Rhaibeh - Mkhurem Fouqani - Sh’airat - El-Herak - Chenan - Saeid - El-Naamieh - Fourqlass - Sadad-Mhina - Kharbeit el-Rdyfatte - Qnya - Houlaya - Mkhurem Tahtani - Boydet el-Rihanieh - El-Raqama - Deir Mar Elyane - Salhieh 9

For a first summary report on all materials pertaining to the exploration of the region Mishirfeh north-

east of the city of Homs see: Al-Maqdissi 2007, pp. 19-27 and Al-Maqdissi 20083, pp. 42-44.

List of References Al-Dbiyat, M. 1995, Homs et Hama en Syrie Centrale, concurrence urbaine et développement régional, Damas. Al-Jundi, Gh. 1984, L’architecture traditionnelle en Syrie, Collection Établissements humains et environnement socio-culturel, 33 UNESCO, Paris. Al-Maqdissi, M. 2007, ‘Note d’Archéologie Levantine, X, Introduction aux travaux archéologiques syriens à Mishirfeh/Qatna au nord-est de Homs-Émèse’, Urban and Natural Landscapes of an Ancient Syrian Capital, Settlement and Environment at Tell Mishrifeh/Qatna in Central-Western Syria, Morandi Bonacossi, D. (ed.), Udine, pp. 19-27 Al-Maqdissi, M. 20081, ‘Réflexion sur Qatna et sa région’, Studia Orontica, III, pp. 3-41. Al-Maqdissi, M. 20082, ‘Matériel pour l’étude de la ville ancienne en Syrie’, Studia Orontica, IV, pp. 5-10 Al-Maqdissi, M. 20083, ‘The Development of trade Routes in the early Second Millennium bc’, Aruz, J., Benzel, K. & Evans, J. M., Beyond Babylon, Art, Trade, and Diplomacy in the Second Millennium bc, New York, pp. 42-44. Al-Maqdissi, M. 2009, ‘Notes d’Archéologie Levantine XVI, remarque sur l’organisation urbaine dans la région Homs à l’âge du Bronze’, forthcoming in the proceedings of Colloque de Lisbonne. Aurenche, O. 1981, La maison orientale, l’architecture du Proche-Orient ancien des origines au milieu du quatrième millénaire, Paris. Bendakir, M. 2008, Archtitecture de terre en Syrie, une tradition de onze millénaires, CRAterre, Grenoble – Damas. Castel, C., Al-Maqdissi, M. & Villeneuve, Fr. (eds) 1997, Les maisons dans la Syrie antique du IIIe millénaire aux début de l’Islam, pratiques et représentations de l’espace domestique, Beyrouth. Pütt, K. 2005, Whonen und Bauen im ländlichen Syrien, Zelte, Kuppeln und Hallenhäusen, Michael Imhof Verlag, Petersberg. Thoumin, R. 1933, La maison syrienne dans la plaine hauranaise, le bassin du Barada et sur les plateaux du Qalamoun, Paris. Tunca, Ö., Meunier, J.-M., Lamisse, J.-Cl. & Stockeyr, E. 1991, Architecture de terre, architecture mère, Liège, Université de Liège.

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In most cases, this architecture has been preserved under exceptional circumstances: - a lack of economic means to transform the former habitat; - the abandonment of a town for economic reasons; - the remoteness of a village development network established by the state after independence; - by the expropriation of former villages such as Mishrifeh-Qatna. The earthen houses studied are usually located on the outskirts of villages and have little varied architectural morphology, controlled technically by the builders of this region. The dome may include one or more parts, building a storage area or a poultry house, or extending throughout the dwelling. Broadly speaking, we present the available material and we hope, by involving all of the attestations of earthen architecture in Syria, to lead to valuable conclusions for the future study of such construction techniques. A comparison with findings preserved in the archaeological record will identify the characteristics of this ancient architecture, which could date back to very remote periods indeed. We present all documentation obtained during the fieldwork in the following summarised descriptions of each selected village.

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El-Rhaibeh Localisation of surveyed domes: southeast Sadad In the village of El-Rhaibeh we identified and surveyed a complex of 23 abandoned domes, complete and in good condition. Separated from the village, the complex is articulated in several parts: a first part is U-shaped with 8 domes on the west side, 3 to the north and 4 to the east; a second part continues east, made up of 3 domes with 2 linked to each other and 1 separated by a wall; and finally a set of 5 domes to the south; the majority of doors open onto the courtyard formed by the complex. The lower part of the wall is made with stones: 4 to 7 layers of stone masonry up to a height of 0.40/0.75 m; the cone-shape domes starting at 1.10 m. The doors are made of wood and measure between 1 m to 1.70 m in height and 0.90 m to 1.10 m in width. There are communicating doors inside between the connected domes, also windows and chimneys. The domes are used as storage room in winter, the interior courtyard is divided by a stone wall forming an enclosure for sheep.

Localisation of surveyed domes: South of Mkhurem Tahtani Mkhurem Fouqani, a town of 600 hectares and 3,658 inhabitants, is located in the middle valley of the Orontes, on a plain 42 km east of the city of Homs. At the northeast of the city, there are several tells. The old town is on the tell-El Shayb. The modern city is developing on 12 km around the old city, which has itself remained a commercial and residential area. The inhabitants rear cows and sheep, and cultivate cereals in dryland farming, vegetables on the plains, grapes, pistachios and olive trees in irrigated agriculture in the mountains. This agriculture is integrated with an environmental project called the “Green Belt”. There is the presence of large-scale production of carpets, a place of storage of animal seeds, and a system of water pipes under the city. There are also schools and vocational colleges. The city has a weather station. A circular cone-shaped dome 2.45 m in diameter has been surveyed; the base is made with stone and adobe and the maximum height is 3.40 m. Standing alone, it is built in mud brick and stone. We may observe 13 openings, either square or triangular, in the upper part of the dome. The height of the dome base is 2.07 m; the wooden door is 1.70 m high and 1 m wide. It is abandoned and, situated beside the entrance to a home, is used as a stable or barn.

Sh’airat Localisation of surveyed domes: southwest of Fourqlass Sh’airat is a village of 1,097 inhabitants on an area of 816 hectares, located southeast of Homs, on a plain facing north. It is administratively part of the city of Raqqama. The earth is brown and limestone is present. The village is located on an archaeological tell 6 km southeast of Raqqama. Traditional houses are built with earth and covered with wooden roofs. In the courtyard of the houses, domes are used as storage room. The people breed sheep and cultivate 2,900 hectares of cereals, almonds and raisins in dry farming. 20 hectares are devoted to irrigated agriculture. There is a school and a governmental grocery. In the village of Sh’airat we identified and surveyed six small domes near Tell Sh’airat; two domes are connected in a court against the enclosure wall, two connected and one independent dome stand outside the court against the wall, and one with a flat roof stands alone in the courtyard of a house. The walls and the dome are made with red mud brick, the doors are from 0.70 to 0.80 m high.

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Earthen Domes and Habitats

Mkhurem Fouqani

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El-Herak Localisation of surveyed domes: South of Mkhurem Fouqani, north of Saeid, south-east of Mishrifeh In the village of El-Herak we identified and surveyed 2 domes, one independent and one associated with a house. The former is abandoned, derelict and at the time not used; it served as a storage room, has a door 1.10 m high and 1 m wide; the lower part of the wall is made with 4 layers of stone masonry up to a height of 0.45 m, the cone-shape dome starting at a height of 0.45 m. The latter dome, used as a barn, has a 2 m high and 1.05 m wide door.

203

Localisation of surveyed domes: North of Saeid In the village of Chenan we identified and surveyed 6 associated domes. Two linked domes were found isolated in a field of olive trees. The domes have a square base of 4 m, the mud-brick walls are 0.72 m thick; the lower part of the wall is made with three layers of stone masonry 0.50 m high. The cone-shape dome starts at a height of 2.15 m. We observed a basin for water or the storing of seeds. There are two doors (1.90 m high and 1.05 m wide) and windows that look north. The four other domes are inside the village: one is close to a house, but now abandoned, with an undefined use but probably a living room. The dome has a square base of 4.80 m per side, the adobe walls are 0.55 m thick, the cone of the dome is incomplete, with an upper edge highlighted by a row of stones. The door is 1.80 m high and 0.80 wide. Two other connected domes are associated with a five-room house and a dovecote. The domes have a square base, the arch between them is 2.50 m high and 3.25 m wide; the total length of all is 11.10 m, the width

is 5.20 m and the wall thickness is 0.70 m; there is only a single exterior door, 1.70 high and 1.00 m wide. The last dome, associated with an isolated house, is abandoned and derelict, and used as a barn; the dome has a circular base of 2.85 m diameter, the wall is 0.45 m thick; the door 0.80 m high and 0.75 m wide; the window is 3.65 m above the ground.

Earthen Domes and Habitats

Chenan

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Saeid Localisation of surveyed domes: Northwest of Fourqlass and southwest of Homs In the village of Saeid we identified and surveyed four domes outside the village. The domes are built with gray mud bricks, the doors are low, with the opening at the top. We identified and surveyed also a triple-domed house in the east of the village with a height of dome ranging from 4 m to 5.50 m, now used for storage and as a barn. The domes have a circular base; the lower part of the wall is made with three layers of stone masonry, 0.30/0.40 m high, the wall thickness is 0.45 m. The doors are oriented to the west, 1 to 1.20 m high and 0.95 to 1.10 m wide. The fourth dome is located in a field of olive trees. The dome has a square base and the lower part of the wall is made with four layers of stone masonry, 0.40 m high.

In the village of El-Naamieh we identified and surveyed nine domes, seven of them in one house where three sets of two domes are connected by an arc and accessible by a door, a unique feature characteristic of this village. The cone shape of the dome begins at 2.35 m height, corresponding to the height of the vertical walls. The walls are built with mud bricks and stone, and the doors of the rooms open to the inner courtyard. The house is organized according to an alternation of domes and terraced rooms, though now it is abandoned and unused. It served as place of residence with the exception of one part which served as a kitchen (now destroyed), function evidenced by the presence of an oven. The seventh dome is circular, and standing alone, it is destroyed and now used as a barn and a henhouse.

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El-Naamieh

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Fourqlass Localisation of surveyed domes: South-east of Homs on the road HomsTadmor In the village of Fourqlass we identified and surveyed thirty-two domes spread over a large territory, sometimes independent, sometimes connected, near or distant from each other. The lower part of the wall is made with stone masonry to a height of 0.25 m. The domes have a square base with a height of 1.83 m. The walls are made with brick laid horizontally and filled with vertical bricks. The dome is completed outside by two layers of stones with steps to facilitate construction and maintenance. The external doors generally have a rounded lintel and open onto the southeast side, 1.80 m high and 0.80 m wide. Inside the house we observed doors (1.85 m high and 1.60 m wide ) also with rounded lintels, windows, chimneys and niches (at 1.10 m height). The dome served as a dwelling or as a stopping off place for merchants and camel caravans in summer and winter.

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Sadad-Mhina Localisation of surveyed domes: on the road of Sadad-Mhina We identified and surveyed an abandoned complex of thirteen domes, some complete or ruined and unusable at present. The domes are connected or independent and of varying degrees of distance apart. The lower part of the wall is made of three layers of stone masonry 0.30 m high. The domes have a square base with a height of 1.70 m. The walls are made with mud brick 0.50 m thick. The cone shape of the dome starts at a height of 1.70 m, corresponding to the height of the vertical walls. The housing complex is comparable to that of Fourqlass: it served as a dwelling or a stopping off place for merchants and caravans as it is on the road of Sadad and Mhina, Qariataine, Tadmor and Qasr el-Heir el-Gharbi, where there are Hellenistic and Roman towers and Byzantine churches.

208

Earthen Domes and Habitats

Kharbeit el-Rdyfatte Localisation of surveyed domes: South of Qnya In the village of Kharbeit el-Rdyfatte we identified and surveyed four domes of which three form part of an inhabited house and are interconnected through communication openings. The domes have a square base with a height of 1.70 m. The lower part of the wall is made with two layers of stone masonry 0.50 m high with a flat, coned top to the dome. The maximum length of the whole is 16.60 m, 5.80 m in height. The mud-brick walls are 0.75 m thick, each room measuring 4.50 m long and 4.80 m wide. The doors face east, with windows on the west side wall. The three are surrounded by an enclosure that forms a courtyard for animals; they were once used for housing and are currently used as a henhouse. The fourth dome is independent.

209

Earthen Domes and Habitats

Qnya Localisation of surveyed domes: South of Houlaya In the village of Qnya we identified and surveyed sixteen domes in the village, some of them in good condition. The domes often have a circular base. The lower part of the wall is made with stone masonry, while the rest of the wall is built with mud bricks and rubble (rubble is broken stone, of irregular size and shape). The dome has a flat end to the cone. Some domes are found in the courtyards of houses and used as stables, others are restored and used as dwellings, while others are abandoned and in ruins.

210

Earthen Domes and Habitats

Houlaya Localisation of surveyed domes: South of Fourqlass In the village of Houlaya we identified and surveyed nine domes in the abandoned village; the domes are dispersed and built with mud bricks. Three domes have a square base of 1.80 m high and are connected to one another. The lower part of the wall is made with stone masonry 0.15 m high, the mud-brick walls are 0.45 m thick. The niches in the interior walls served as living quarters and indicate that it was a dwelling place. All three domes measure 16.20 m. The doors are 1.0 m wide, those of the first and third domes are filled; their function is undefined, perhaps serving as an entry for animals.

211

Earthen Domes and Habitats

Mkhurem Tahtani Localisation of surveyed domes: north of Mkhurem Fouqani and northeast of Mishrifeh In the village of Mkhurem Tahtani we identified and surveyed eleven domes in the village, independent or connected, serving as houses, barn or storage; they are located in the courtyards of the houses and have square bases: - two domes at the corner of a house; there is an oven in one and the other was used as a barn. The lower part of the wall is made with three layers of stone masonry 0.50 m high. There is a door 1.70 m high and 0.90 m wide. Three rooms of the house are used as habitation, demonstrated by the presence of niches and reinforcements of the walls for storage, and wells near the house. - two domes are on the west side of a house, one complete and one destroyed, once served as dwellings and currently used for storage. - three domes with a square base are connected to a house; one is ruined, the others complete, once served as dwellings and currently as stable and barn. - two domes in good condition are connected as part of a house, there is an oven in one of the two. - two domes in good condition are connected to a house; they were once used for dwelling and currently as storage, henhouse and hutch.

212

Earthen Domes and Habitats

Boydet el-Rihanieh Localisation of surveyed domes: between Mkhurem Fauqani and Mkhurem Tahtani. In the village of Boydet el-Rihanieh we identified and surveyed one abandoned and isolated dome in an olive field outside the village; it is ruined and not used at present but served as a barn. The lower part of the wall is made of four layers of stone masonry 0.50 m high. The domes are of a circular base 3 m in diameter, the wall of the partially destroyed dome is made of stone and mud bricks 0.40 m thick and 2.50 m high; the door is 0.90 m high and 0.80 m wide.

El-Raqama Localisation of surveyed domes: South-east of Homs and south of Shâ&#x20AC;&#x2122;airat El-Raqama is a district of 10,531 inhabitants located in the region of Homs. It includes 16 villages and 5 farms, plus the small village of ElRaqama. This is 34 km south-east of Homs. Traditional houses are built of earth and stone, and are covered with wooden roofs. The inhabitants cultivate dryland cereals and grapes and almonds in irrigated fields. They also breed sheep. In the village of El-Raqama we identified and surveyed a dome to the north side of the village. It is complete, but abandoned and unusable, and is built with red mud bricks. The dome has a square base with a wall 2 m high and an east facing door.

Salhieh Localisation of surveyed domes: north-east of el-Herak Salhieh is a hamlet of 172 inhabitants located at 550 m altitude in the upper valley of the Orontes (in the territory of the village Alnzarih). It is located at 1 km from Alnzarih, on a plain which gently descends from the north to the Orontes, at about 2 km distance. To the south and east there is the Lebanese border. The total area of this small village is 300 hectares, including 250 of farmland (potatoes, beets, corn and peas for irrigated lands, cereal for dry lands). The population breed cattle and sheep, working in a co-operative association. In the village of Salhieh we identified and surveyed three domes in an abandoned three-roomed dwelling house with courtyard. The one single dome and two joined have a rectangular base. The lower part of the wall is made with layers of stone masonry 0.60 m to 0.70 m high. The interior door connecting the two domes is 1.64 m high and 0.90 m wide.

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Earthen Domes and Habitats

Deir Mar Elyane Localisation of surveyed domes: Near the town of Qariataine Deir Mar Elyane is a monastery located 3 km northwest of the town of Qariataine. In the village of Deir Mar Elyane we identified and surveyed two modern cupolas in front of the entrance of a former convent. Built on the initiative of the head of the convent and used for housing or guest accommodation, it is an example of an ecological building.

214

Earthen Domes and Habitats

The area of earthen dome houses is extended from Ar-Raqqah city, belonging to ‘Al-Jazira and Euphrates Region’ (from the east), passing through Aleppo region to Idlib city (in the west), known as ‘Aleppo Hadaba (hill) Region’, covers two of eight geographical regions of Syria, which is divided into fourteen Administrative Regions.1 Before analyzing the mud architecture distribution in Syria, it is necessary to outline briefly about the relation between rainfall and number of existent human settlements or villages in each geographic region: for this reason we organized a table that demonstrates these important data and information which illustrate the relation between them under the effect of geographic division, and to imagine the probable effect of this relation on the distribution of earthen architecture in whole Syria. Rainfall mm/year Geographical Region

Min.

Max.

Aver.

Area Km2

135 521 275 51,000 1 Al-Jazira and Euphrates 2 Aleppo Hadaba 190 500 336 20,000 3 Al Hass River Basin 208 1,221 517 16,310 4 The Coast and coastal mountains 1,078 1,530 1,270 6,700 5 The Syrian Centre 129 150 140 20,100 6 The Syrian Desert 58 104 81 58,100 7 The High Mountains 136 1,133 633 5,129 8 The Western South Region 116 483 256 12,650 Total 189,989

Population Habx1000 1,806 2,454 1,907 1,911 45 50 386 3,399 11,958

Directorate of Antiquities and Museums of Aleppo, Syria

these data we can observe that the minimum density of Population distribution is found in Syrian desert region, the maximum one is noticed in Syrian coast and coastal mountains, and also that Al-Jazira Region has the higher number of human settlements and villages (2,175 ones) while the desert region has only 20 aggregations according to the geographic information of 1990. From the other hand we can mark the relation between the rainfall and the number of aggregations through the following diagram, and notice that this relation is defined by many factors: the different rainfall registrations of various stations spread on the area of each region, the proper region climate and its geological and morphological characters.

Population Number of Density Settlements Hab/Km2 35 2,175 122 1,400 119 1,310 318 1,315 2 100 0.8 20 77 53 283 589 63 7,002

Tab. 1: Main data concerning the geographical regions of Syria.

In table 1 we may see the data of the minimum, maximum and average rainfall of the geographical Syrian regions related to area, absolute number of people, people density and number of settlements.2 Through The Geographic Regions in Syria are: Al-Jazira and Euphrates, Aleppo Hadaba and Ashamia Ashamalia, Al Hass River Basin, the Coast and coastal mountains, the Syrian Centre, the Syrian Desert, the high mountains, the Western South Region. While each administrative division is known as ‘Muhafazah’, the administrative divisions ‘Muhafazat’ are fourteen: Al-Hasakah, Aleppo, Ar-Raqqah, As-Suwayda, Damascus, Daraa, Deir ez-Zor, Hama, Hims, Idlib, Latakia, Quneitra, Rif Dimashq, Tartus. 2 The data are from: Abd Assalam 1990.

Saverio Mecca

University of Florence, Italy

Fig. 1: Relation between rainfall and number of human settlements.

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Earthen Domes in Northern Syria. Ar-Raqqah, Aleppo, Idlib

Mohammed Dello

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Earthen Domes and Habitats

Fig. 3: First use of inclined roofs in Mureybet site (Cauvin 1984).

Annual Rainfall Average (according 1990) 81 mm/year 140 mm/year 256 mm/year 275 mm/year 226 mm/year 517 mm/year 633 mm/year 1270 mm/year

Hight density Low density

Fig. 2: Map showing the distribution of mud architecture and the geographic division of Syria with their annual rainfall average according to 1990.

On this basis we can reflect on the distribution of earthen architecture in Syria: the earthen architecture is distributed basically in three large regions: Al-Jazira and Euphrates, Aleppo Hadaba and the Syrian Centre, besides to the eastern part of Al-Hass Basin and the northern part of the Western South region.3 We can justify this distribution and localization of earthen architecture by the following reasons: - The Coast and coastal mountains region is generally bare from earthen houses, because it has highest annual rainfall in Syria which influence the durability of mud architecture from one part, from other part the mountains cover the biggest area of that region, and the stone can be good important alternative material from earth as a material construction - All Al-Hass Basin region, high mountain region and Western south region do not have earthen architecture except some plains, because they are rich of stones which allow people to construct their houses. - The Syrian desert is completely poor of earthen houses, because of its

not appropriate earth for making bricks and its hot and arid climate which reduced the number of human settlements and villages. - Usually there are dense and slight distribution of mud architecture in the regions of Aleppo, Al-Jazira and the Syrian centre; this distribution depends on the variety of local earths in each zone and its validity for construction, on the number of human settlements and the density of population and depends on the number of masonry experts in each zone. Elements of earthen dome architecture history in Syria. If we want to understand the architectural culture of earthen domes of northern Syria, we need to look at them in the frame of the history of Syrian earthen architecture: the today dome architectures have very deep and far roots4: - In the 9th millennium bc, Aswad site (near Damascus) knew a circular houses dug in earth, covered probably with cane treated by mud. - The early architecture started in Al-Jazira and Euphrates region at the middle of the 8th millennium bc, as houses dug partly in earth or rock (Abu Huraira site), while Mureybet site has in the same period circular houses dug in earth, built from mud. Both of these houses perhaps were roofed with a light trunks treated with mud (Fig. 3).5 - The beginning of using the dome, can be probably identified in the inclined roofs of circular houses in Mureybet site (8th millennium bc) which were the first step to joint the dome, because the roofs were generally flat from the 9th millennium to 5th millennium and made from cane treated with mud, brushes and poplar, as in the following sites: Um Al-Dabbaghiyah (9000 bc), Abu Huraira (8000 bc), Buqros (6800 bc), Tell Hasan and Tell Aswad (6500 bc). See the contribution of Ă&#x2013;nhan Tunca & Katrien Rutten, The corbelled dome in the archaeology of the ancient Near East. Cauvin 1984, p.53.

The map is elaborated from many resources, mainly from Abd Assalam 1990 and Ali n.d.

- The early dome was, probably, built in Halaf Civilization (5000 bc) and in Arpachiyah site (5000-4000 bc).6 - The attempts to use earthen domes did not stop in Mari architecture and Al-Salankahiyah site in the third millennium BC besides to arches and vaults in Tell Arramah and to use flat roofs in Tell Brak in the same period. - In the second millennium bc the roofs in Tell Bderi, Tell Al-Khwaera and Ashaikh Hamad site were flat, while they were inclined (in two directions) in Mozan site. Urban morphology of earthen dome villages Among the earthen dome architecture villages of north of Syria which have been examined we may identify two main urban morphology types: 1 spontaneous villages, where the houses are spread spontaneously, there are not shaped streets, squares or precise limited urban spaces, (Fig. 4) 2 semi-regular villages, which have a general public space, semi-private spaces, main streets and more narrow streets, Zuqaq, besides to mosque, 3 Regular villages, which have a principal square, small squares (semiprivate space), perimeter roads, interior main streets and more narrow streets, Zuqaq, besides to mosque and open market, Bazar (Fig. 5). A first classification of Syrian dome houses In order to outline the earthen architectural culture we examined about twenty examples distributed in three regions, Al-Jazira, Aleppo Hadaba and Al-Hass basin, as followings: 1 Al-Jazira region (Ar-Raqqah Muhafazah): Al-Baeda and Laqta village. 2 Aleppo Hadaba region: a. (Aleppo Muhafazah): Al-Aremeh, Al-Bab, Bzaâ&#x20AC;&#x2122;a, Soran, Tyara, Khan Toman, Al-Wdehi, Abteen, Al-Safirah, Blas and Hamedeeh. b. (Idlib Muhafazah): Kelli, Ezmareen, Al-Mastumeh Maâ&#x20AC;&#x2122;arrat an Numan and Kafranbel. 3 Al-Hass basin region (Hama Muhafazahh): Salamiyah.

Mellart 1990.

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Earthen Domes and Habitats

Fig. 4: Spontaneous urban spaces in Aleppo (Blas). Fig. 5: Shaped and limited urban spaces in Aleppo (Abed).

218

Earthen Domes and Habitats Muhafazat of Aleppo: 1 Al Aremeh, 2 Bzaâ&#x20AC;&#x2122;a, 3 Soran, 4 Tyara, 5 Khan Al Asal, 6 Khan Toman, 7 Al Wdehi, 8 Abteen, 9 Al-Safirah, 10 Blas, 11 Hamedeeh Muhafazat of Ar-Raqqah: 1 Al-Baeda, 2 Laqta Muhafazat of Idlib: 1 Kelli, 2 Ezmareen, 3 Al-Mastumeh, 4 Kafranbel Muhafazat of Hama: 1 Salamiyah Fig. 6: Localization of the selected villages.

The elements of a basic earthen house may be the followings: one or more rooms with various functions (living, sleeping or for visitors), kitchen, bath, store, stable, toilet, fences, garden, small store for hens and pigeons, earthen traditional bakery Tannur, stage Mastaba, and well (Fig. 7). On the basis of plans and shapes of mud houses we may identify several types of houses affected by social, economic, religious and traditional factors. We may distinguish between two principal typologies according the openness level: - enclosed houses, - and unclosed ones. Fig. 7: Plan of enclosed domed earthen house in Aleppo (Blas), composed of typical parts.

Under these two main typologies we can see other secondary ones: - line-houses, - dome-houses, - plot-houses - and single-room houses.7 The enclosed houses are nearly more spread in Idlib and Aleppo than ArRaqqah, because: - most people of Idlib and Aleppo region are peasants, while there is a high percent of nomads in Ar-Raqqah and Al-Jazira region (and some eastern areas of Aleppo) which move and work as pastors of animals and do not spend long time in their unclosed houses. - these typologies are related to the privacy concept adopted from proper habitants: because the habitants of unclosed houses (in some eastern villages of northern Syria), are not so interested of privacy as the habitants of enclosed houses (as in some villages in Aleppo and Idlib) because of religious values or social traditions. Sometimes the economic factor influences positively the number of enclosed houses, because rich people can feel more safe and protected from strangers or animals. Examples of enclosed houses are in Aleppo (Argel, Al-Safirah, Blas, Bzaâ&#x20AC;&#x2122;a, Kelani, Khan Toman and Soran), Idlib (Al-Mastumeh, Ezmareen and Kafranbel) and Hama (Salamiyah). According a second classification criterium based on shape of domed houses we may identify these architectural types: 1 Line-house: with a row of non-interrelated rooms, sometimes this line is extended in one direction, in two or three directions (Fig. 12). 2 Domed circular rooms: sometimes they are separated as in Idlib (Jobas) or connected as in Hama (Salamiyah) (Fig. 13). 3 Plot-houses: can be enclosed, or without fences built on regular plot defined by a large base mastaba; they are a characteristic urban feature of 3rd millennium Northern Mesopotamia. 4 Single-room-houses: are typical of the 3rd millennium sites of Tell Raqai and Tell Halwa. Examples of them can be found in many villages, especially in Idlib (Abu Kansa) and in Aleppo (Hamedea and Al-Wdehe) as in figure 8.Two or three rooms can be on the same row with one or more doors, examples of these are in Ar-Raqqah (Al-Baeda), In Aleppo (Tyara, Al-Safirah, Khan, Al-Asal, Azzan, Hamedeeh and Abed) and in Idlib (Abu Kansa and Murrat Al-Numan) ( Fig. 9). 7

Pfalzner 1996, p. 74.

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Fig. 8: Single room house in Aleppo (Hamedeeh). Fig. 9: Two rooms house in Aleppo (Khan Al Asal). Fig. 10: Three attached rooms in Idlib (Kafranbel).

Fig. 11: Four attached rooms in Aleppo (Bza’a). Fig. 12: Line-house in Hama (Salamyia). Fig. 13: Two connected domes in Hama (Salamyia).

5 Attached-rooms-houses: these houses are rare, sometimes we saw three domed rooms situated together as in Idlib (Kafranbel), Aleppo (Azzan) and in Ar-Raqqah (Laqta village) (Figs. 10-11). According a third classification criterium based on shape of dome we may identify these architectural types: 1. Circular domed rooms: in this typology the dome starts from earth level (Fig. 14). 2. Quadrate domed rooms: they are named ‘normal dome’ and ‘Sultan dome’, Qubba Sultanya, which means ‘the dome of the Sultan’; they are basically similar to circular domed rooms but the dome does not start from earth level, but it rest on walls starting from different heights (normal dome: 10-90 cm; sultanya dome: 1-2.5 meters). The Sultan domes usually have been built by rich people, as their construction (as we will see in the next paragraph) is more complicated relating to the first type (Fig. 15).

Construction technique of earthen domes. Most of the earthen domes in North of Syria are built with three main earthen building techniques: earthen bricks (adobe), cob and mud-stone technique. There are other mud building techniques used in northern Syria as torchis and pisè techniques. If we look for the history of earthen architecture techniques in Syria, we may see that the local techniques were discovered many thousands of years ago: - The most ancient evidence of the torchis technique is in the interior walls of the circular houses in Tell Mureybet8 at the end of the 9th millennium bc,

Fig. 14: Simple domes in Idlib (Giobas).

Fig. 15: Sultan domes in South Aleppo.

The site of Mureybet, along the middle Euphrates River, was occupied from the 12th to the 8th millennium bc. It can be considered one of the earliest known agriculture-based settlements, the domestication of plants was traced in successive strata, making of Mureybet one of the reference sites for the progress of the Neolithic in the Ancient Near East. In 1971, Jacques Cauvin began the excavation at Mureybet, and discovered that the people of Mureybet at the earliest levels lived in round houses made of limestone bricks, with a clay mortar. In later strata, houses were rectangular. 8

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Earthen Domes and Habitats Fig. 16a: Earthen brick technique (adobe) in Hama region (Salamiyah). Fig. 16b: Earthen brick technique (adobe) in Hama region (Salamiyah).

Fig. 17a: Cob technique in Idlib (Giobas). Fig. 17b: Deatil of cob technique in Idlib (Giobas).

- The oldest pisè technique evidence is almost known in the roofs of Tell Mureybet (8000 bc) and in Tell Ashaekh Hasan (7000 bc).9 - The oldest adobe technique evidence has been found nearly in, Tell Mureybet, Abu Huraira site (7000 bc), then in Tell Ashaekh Hasan site and Tell Aswad (6500 bc); this technique was used also in Mari site, Hammam Turkman, Tell Arramah, Tell Brak and Tell Khazna (third millennium bc). In the second millennium BC Tell Al-Bae’a, Tell Ashaeekh Hamad and Leilan site have walls of adobe. - The oldest cob technique evidence is known nearly in Tell Halaf (5000 bc) and Arbagiyah site (5000-4000 bc). The today all the earthen architecture techniques are present in Syria: earthen bricks masonry or ‘adobe’ (Attub or Al-Leben), cob (Teen or Dewar), mud-stone (Teen-Hajar) (Figs. 16-18), ‘pisè’ (Turab Madkuk) and ‘torchis’ technique (Khashab-Teen). Earthen bricks, cob and mud-stone masonry techniques are approximately common in all the three regions: Ar-Raqqah (Al-Jazira and Euphrates region), Aleppo and Idlib (Aleppo Hadaba region), and Hama (Al-Hass Basin region). Instead ‘pisè’ walls are less present because this construction technique needs more complex instruments and more work than cob technique. The ‘torchis’ technique is not present, except used in few small examples as animals stable, otherwise this technique is very common in the old city of Damascus. The main reason of the scarcity may be connected with the poor availability of raw materials employed by the proper technique, because the regions of Al-Jazira and Aleppo Hadaba are poor of wood and trunks, the main material of ‘torchis’ technique.

The mud-stone technique is diffused mainly in Idlib and in the western parts of Aleppo Hadaba region. This technique is very similar to cob technique except that the mud mixture of walls contains small unshaped stones and gravels, while the walls built with cob contain only mud with gravels and generally have not small stones in them. the diffusion of this technique in the up cited zones could be caused by the following factors: - Idlib and the western parts of Aleppo Hadaba are more rainy than the other regions (East of Aleppo or Ar-Raqqah), because mud-stone walls resist rain and water more than cob walls. - The clay in Idlib and western parts of Aleppo Hadaba is red and more rich of the ‘montmorillonite’ mineral than other regions; this mineral (as it is known) is responsible of water absorption and then of following shrinkage after the evaporation, for this reason it is impossible to build walls made completely of red mud mixture without supporting materials as small stones (the difference between cob and mud-stones). - In some zones of Idlib area the cob technique is named Dewar, the

Cauvin 1984, p. 53.

Fig. 18: Mud-stone technique in Aleppo (Saint Simon).

walls are constructed by an orange earth named Gedare which means ‘valid earth to build a Gedar (a wall)’. The name of this technique Dewar is derived from the word Dawr (course), because the technique consists of building one dawr or two ones (courses of mud) in one day, one at the morning, second at the evening (Fig. 19).

Dome shapes Although there are many differences of dome shapes in different areas the common character is that all of them, built with adobe technique, are corbelled domes, because their courses are set horizontally or better slightly tilted inwards, each course is laid out according to a spiral and cantilevered over the one before. Main forms of earthen corbelled domes in Syria are parabolic, catenary, conic or multi-conic and truncated (Figs. 21-22-23). The comparison between domes shapes gave us the following results: - The normal simple domes in all regions (which start directly from earth level) are higher than sultanya domes, this means that the ratio ‘height/

Earthen Domes and Habitats

Earthen domes shape and structure in northern syria. We may identify two principal typologies of earthen domes: normal dome and Sultan dome ‘Qubba Sultanya’, this classification depending on the height from which starts the bottom circular base of the dome and on relation between the proper dome and the squared basement wall. We may observe the difference of mud dome shapes in Ar-Raqqah, Aleppo, Idlib and Hama and the method of dome construction in these regions according to diverse techniques. In ancient architecture of Syria the initial shapes of earthen houses roofs were flat for thousands of years, then the domed roofing started nearly in Tell Halaf (5000 millennium bc) and continued till nowadays and have been in use for centuries in traditional Syrian rural architecture. It is well known in Syria that domes are better than flat roofs because their ogival shapes is cheaper, resist rain leakage, having less surface exposed to sun in the summer reduce solar radiation, achieving generally good climatic conditions in the interior space of the domed rooms. Generally the thickness of the Syrian earthen domes at the bottom depends on singular adobe brick dimension, between 35-50 cm, it is more slim at the top, between 15-20 cm (Fig. 20).

221

Fig. 19: Dewar technique or cob, is composed of earthen rows of mud in Hama region. Fig. 20: Thickness of dome base is variable from place to another in South Aleppo.

Fig. 21: Triangular Domes in Ar-Raqqah city.

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Earthen Domes and Habitats Fig. 22: Parabolic Domes in South Aleppo.

radiusâ&#x20AC;&#x2122; is higher in normal domes, for that they seemed to be more slim (Figs. 24-26). - The Sultan domes in Ar-Raqqah are wider at the bottom than ones at Idlib and Aleppo (the ratio â&#x20AC;&#x2DC;height/radiusâ&#x20AC;&#x2122; is lower). - Only in rare cases earthen sultanya domes built on stone can be found (Fig. 27). - The ratio between dome height and supporting walls height in Sultan domes is variable from 1/2 to 2 (Fig. 28). - basically, while the exterior shape of the dome tends to be parabolic, the interior shape tends more to be conic or better composed of many truncated cons with three or four divers inclinations (Figs. 29-30). Dome Construction methods About construction method we may distinguish two principal techniques depending on the type of dome: normal dome (circular or square basis) and Sultan dome (supported on walls). - The first type which start at ground level or above on a foundation wall, is the simple and the same in adobe or cob technique Dewar. We may distinguish two sub-types: circular basis or square basis - the circular normal dome is the basic dome type, there are not complicated details, nor specific structural elements because the builder begins to form the dome shape from the ground level with a circular plan and do not need transition from one shape to another. - the square normal dome is an evolution of the basic dome type, there are not complicated details, nor specific structural elements although the builder begins to form the dome shape from the ground level with a square plan and start to lay the bricks smoothing the corners in order to get transition from square shape to circular shape with 8-15 layers.

- The second type is the Sultan dome which is built on high or low square perimeter walls made of adobe, getting the transition from square to circle with the perimeter wall. We may distinguish two sub-types: dome supporting on perimeter wall with an external and an internal course or dome supporting on whole perimeter wall with an internal side shaped to get transition to circle. - The dome supporting on an internal course are structurally close to the square normal dome, the exterior adobe or stone course stops nearly when the interior wall reach a circular shape or a little higher above it. - The dome supporting on whole perimeter wall with a partial integration of pendentives. The transition from square to circle The building culture developed through thousands of years in Syria many ways to achieve the transition from square shape to circular one for realizing or supporting earthen corbelled domes: Fig. 23: Triangular Domes in Euphrates region. Fig. 24: Sultan domes in Hama region.

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Fig. 25: Truncated Domes in Hama (Salamiyah).

Fig. 26: Simple domes are higher than Sultan ones in Hama region (Cheik Hilal).

Fig. 27: Domed stone rooms in Ar-Raqqah.

Fig. 28: Height ratio â&#x20AC;&#x2DC;dome/room wallâ&#x20AC;&#x2122; in Aleppo (Habbuba).

Fig. 29: Exterior shape of a Domes in Hama region (Cheikh Hilal).

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Fig. 30: A dome built in 2008 in Hama region (Cheikh Hilal).

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- Domes on ‘false’ pendentives: this is the most diffused way: the transition to circular start with a corbel (a stone, a piece of wood or an earthen brick) in the angle on which the internal side of the wall is progressively, layer by layer in a corbelled way, shaped and adapted to a circular internal perimeter on which the corbelled dome will rests (Fig. 31). - Domes on pendentives: in this case the dome rests on lower parts which have regular pendentives10, at the corners of the square walls (Fig. 32). - Buttresses: there are buttresses integrated with the walls, they form a first circular course of the dome, then the dome is so designed and lifted row after row of bricks adjusted by the expert mason muallem according to radius and inclination (Fig. 32). - Squinch dome: whose lower circle is inscribed on the square and the interconnecting surfaces, called squinches11, are composed of a series of arches of increasing radius or truncated dome resting on the inscribed diagonal square with the surfaces thus left being the squinches.12 List of References Abd Assalam, A. 1990, Syrian Geographic Regions (in Arabic), Damascus University. Ali, A. n.d., Al-Insan wa Al-Amara (in Arabic), Aleppo. Aurenche, O. 1981, La maison orientale, l’architecture du Proche Orient ancien dès origines au milieu du quatrième millénaire, Paris. Besenval, R. 1984, Technologie de la voûte dans l’Orient ancien, Editions Recherches sur les Civilisations, Paris. Cauvin, J. 1984, Al-Wahda Al-Hadariyah Fe Belad Al-Sham 9000-8000 bc, translation of Twer Q., Damascus. Mellart, J. 1990, The oldest civilities in the near east, translation of Tallab M., Damascus. Pfalzner, P. 1996, ‘Early Bronze Age Houses in the Syrian Djezireh’, International Colloquium The Syrian Djeireh – Cultural Heritage and Interrelations. Deir ez-Zor, Minke, G., 2006, Building with earth. Design and technology of a sustainable architecture, Berlin.

A pendentive is a constructive device permitting the placing of a circular dome over a square room or an elliptical dome over a rectangular room. The pendentives, which are triangular segments of a sphere, taper to points at the bottom and spread at the top to establish the continuous circular or elliptical base needed for the dome. In masonry the pendentives thus receive the weight of the dome, concentrating it at the four corners where it can be received by the piers beneath. Prior to the pendentive’s development, the device of corbelling or the use of the squinch in the corners of a room had been employed. http://en.wikipedia.org/wiki/Pendentive. 11 A squinch in architecture is a piece of construction used for filling in the upper angles of a square room so as to form a proper base to receive an octagonal or spherical dome. It was the primitive solution of this problem, the perfected one being eventually provided by the pendentive. Squinches may be formed by masonry built out from the angle in corbelled courses, by filling the corner with a vise placed diagonally, or by building an arch or a number of corbelled arches diagonally across the corner. http:// en.wikipedia.org/wiki/Squinch. 12 Minke 2006, p. 118. 10

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Fig. 31: A complex relation between basement, â&#x20AC;&#x2DC;falseâ&#x20AC;&#x2122; pendentive and dome masonries. Fig. 33: Domes based on buttresse in Ar-Raqqah city.

Fig. 32: Domes on pendentives in Idlib (Giobas). Fig. 34: Domes based on a squinch in Fourqlass

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Central Syria, namely the region situated east of the Hama-Aleppo highway, is characterized by a rapid succession of different environments. This background has always required populations to adapt their settlement strategies and modes of subsistence to these environments. In this region we may observe the main earthen dome habitats to be still active. The Byzantine period (4th–7th centuries) witnessed a strong trend of people settling eastward, a process which would result in greater climatic constraints. These new settlers developed the capacity to adapt to their environment. Among those distinct environments, there are three basalt anticlines situated east and northeast of Hama, which can illustrate this capacity to adapt and the great diversity of settlement patterns. Those plateaus all show the same geological features, but their individual geographies permit the distinguishing of each of them in turn. On the one hand, the group formed by the Jebel al-Hass and the Jebel Shbeyt, 80 km northeast of Hama, surrounds the al-Jabbul salt-water lake. Both reach an elevation between 450 and 500 m, quite similar to that of Jebel al-‘Ala. On the other hand, the Jebel al-‘Ala, situated 15 km east of Hama, is, like the two other tablelands, a basalt plateau coated with a flow of basalt, at an elevation of around 500 m (Fig. 1). Climatic features First of all, differences between these three plateaus relate to climatic issues. Their situation in Central Syria entails rainfall variations affecting both cultural habits and subsistence strategies. The Jebel al-‘Ala is located in an

Altitude (m) 72-330 340-450 460-610 620-850 860-1400

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Marion Rivoal

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Byzantine settlements and management of environmental resources in Central Syria: the case of the basalt uplands

Nazir Awad

Directorate General of Antiquities and Museums DGAM Ministry of Culture, Damascus (Syria)

Institute Française du Proche-Orient Damascus, Syria

village hamlet Monastery Other scattered habitat

Fig. 1: Map of areas surveyed

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area endowed with average rainfall of 300 to 400 mm p.a., whereas in most parts of the Jebel al-Hass and the Jebel Shbeyt, the amount of annual precipitations fluctuates between 200 and 300 mm. Theoretically, these totals allow rainfed agriculture without any additional irrigation. In fact, irrigation is supposed to be essential for cultivation below an annual rainfall mean of 200-250 mm. However, one of the most important restrictions when it comes to precipitations in Syria happens to be the significant variability of rainfall from one year to the next. This, therefore, implies that the location of the 200 mm isohyet changes and, as a result, the limits of the areas of rainfed and irrigated crops migrate depending on how dry the year is. This variability in rainfall grows in magnitude as one moves away from the seashore and from the area of Mediterranean climatic influence. In terms of rainfall, the Jebel al-‘Ala, the westernmost basalt plateau, is subject to lesser variability than the other two areas. During arid years, both the Jebel al-Hass and the Shbeyt receive less than 100 mm of rainfall, whereas the Jebel al-‘Ala maintains an amount of precipitation between 100 and 200 mm. In fact, below the 100 mm line, one should not speak of a ‘steppe area’, but rather of a ‘desert’. Background studies Several studies were carried out on these basalt tablelands, the earliest at the end of the nineteenth century and the beginning of the twentieth.1 A major aerial survey, undertaken by René Mouterde and Antoine Poidebard in the mid-1950s yielded new data concerning occupation features of these regions, and showed that a great number of ancient sites developed on and around these basalt tablelands. Generally associated with a field survey, sometimes with sketches and plans, these aerial observations remain an essential tool for the study of this area. Much later, in 1983, Claus-Peter Haase discussed their work in the Jebel Hass and the Jebel Shbeyt in a short article, which, for the first time, reconsidered the military hypothesis supported by the two French scholars, and also the chronology, until then generally considered Roman. From 1995 up to 2001, a new survey over a large area, involving several speHoward Crosby Butler has focused as early as 1899 on certain ancient settlements of the Jebel Hass and the Jebel Shbeyt. Some twenty years later, he published others studies dealing with some sites located in the Jebel al-‘Ala. In a more systematic way, the same area has been surveyed soon after by a French scholar, Jean Lassus, in the 1930s. His study is closer to an inventory.

cialists from different scientific fields, was carried out under the supervision of Bernard Geyer. It focused on the ‘arid margins’, i.e. a fringe between the dry farming and the irrigated zones, and its results revealed various occupation phases, the most important lasting throughout the Byzantine period; this phase of settlement was even more substantial than the one currently taking place. An element of this program was Jean-Baptiste Rigot’s PhD in geography dealing with the diachronic occupation of the area around the al-Jabboul, essentially the eastern slopes of the Jebel al-Hass and the northwestern ones of the Jebel Shbeyt. In 2006, I undertook a brief survey focusing on the top of Jebel Shbeyt and the southern and eastern valleys of the plateau.2 Naturally, the amount of available data varies widely between the various basalt plateaus. For instance the whole Jebel al-‘Ala, together with the Hass plateau summit, remains insufficiently investigated. Only a few buildings, mostly churches, sometimes towers and very rarely houses, caught scholars’ attention during the first half of the twentieth century. Features of the various towns and settlements have not yet been studied and one will only find a few remarks concerning perimeter walls; the chronology of some strongholds, moreover, remains unclear. Various settlements (mostly in the Jebel al-‘Ala) were reoccupied during the Ayyubid period, and once more as early as the first half of nineteenth century. The result is that Byzantine buildings underwent various adjustments, which prevent us from understanding not only each construction on its own, but also the internal organization of the nucleated settlements. Nevertheless, in spite of the disparities between the sets of data, an identity for this area based on the plans provided by the first inventories, these being compared in turn with observations of the northeastern basalt uplands, shall be attempted. Construction features In terms of typology, the contrast between materials used on the one hand in the Jebel al-‘Ala, and on the other in the Jebel al-Hass and Jebel Shbeyt, has a deep impact on architecture. In the Jebel al-‘Ala, most of the buildings were made of basalt, usually squared and roughly faced stones on both sides of the walls laid in clay mortar. Stone is generally used for the whole building, sometimes with

This survey had been made possible thanks to the financial support of the Institut Français du ProcheOrient and with the authorisation of the Syrian General Direction of Antiquities, to which I would like to express my grateful thanks.

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stringer courses: this is especially visible on photographs of towers (Fig. 2). Some architectural characteristics, derived from the use of basalt, are similar to those found in Southern Syria (the Hauran), and therefore deserve to be examined more closely. In those buildings entirely made of basalt, several transverse arches and vaults, built in order to support roofs, can be observed in houses and towers; these vaults divide the length of rooms. Basalt slabs, laid perpendicularly to the axis of arches, are used to create the ground floor of the upper level. In the Jebel al-Hass and the Jebel Shbeyt, however, very few buildings have been shown to be exclusively made of basalt: this is true in the case of a few churches (for instance, those of Zebed), towers and other atypical constructions. The features characteristic of the Jebel al-â&#x20AC;&#x2DC;Ala, such as those present in the Byzantine constructions of Southern Syria, can, nevertheless, be traced in the few basalt constructions of those tablelands: such is the case of the At-Tuba warehouse, the Rasm al-Hajal basalt building. According to another technique, corbels were also used to support the long basalt slabs of roofs or intermediate floors (for instance at Al-Burj tower). Otherwise, in the two eastern basalt plateaus, mud brick was the common construction material. In this area, mud-brick walls were raised on a foundation made of available stone, i.e., once more in this region, basalt. This short foundation could be built of pebbles or roughly squared stones, and would have preserved mud-brick walls from moisture. A general, but not exclusive, form of roofing in these jebels was a mud-brick dome, the length and width of rooms being specially designed to adapt to this feature, as with the mud-brick domes we may observe today in the region. Nevertheless, basalt buildings appear to have been mostly covered with a frame and roofed with tiles. Some mud-brick constructions (including churches and houses) seem to have been roofed in the same way, but the ratio between the mud-brick buildings covered with mud-brick dome and those covered with frame and tiles is not known. Fired bricks do not seem to exist in the Jebel al-â&#x20AC;&#x2DC;Ala, whereas one can find some buildings made of this material in the easternmost mesas. Scattered in a region between the Jebel al-Hass and the Jebel Shbeyt, they seem to be confined to large settlements, and appear to be slightly more frequent than one would expect. During the last survey, I recorded three of those constructions in the village of Rasm ar-Rbeyt, on the foothills of Jebel al-Hass, and one at Rasm al-Hajal, on the eastern side of Jebel Shbeyt. Brickwork was

Fig. 2: Tamak tower (Butler 1920, fig. 8)

Fig. 3: Traditional architecture: mud-brick dome on basalt foundations at Rasm al-Hajal Fig. 4: Rasm al-Hajalâ&#x20AC;&#x2122;s baths: baked-brick masonry on a basalt base

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supported by the very same stone base seen in mud-brick buildings: two rows of basalt squared stones are filled with earth and clay (Fig. 4). Large Nucleated Settlements As seen on the global map showing the distribution of agglomerations (Fig. 1), this type of settlement is to be found on each of the basalt hills, although they are more concentrated in the Jebel al-‘Ala. Twenty of the 42 listed settlements of this plateau belong to the ‘large nucleated type’, but this is the case in only 15 of the 45 listed for the Jebel al-Hass, and in 13 of the 48 settlements recorded in the Jebel Shbeyt. Several types of nucleated settlements, however, need to be distinguished here: what are described are clustered settlements; these can be anything from hamlets, whose main characteristic is the absence of a church, to cities. During antiquity, only one settlement was granted with ‘city’ status in the area under discussion, namely modern Khanaser, ancient Anasartha, situated in the Munbatah corridor between the Jebel al-Hass and the Jebel Shbeyt. Hamlets are characterized by an organic form of development, a consequence of a family’s increase in numbers, which entails the construction of new houses, but without any preconceived, organized pattern. The village, somewhere between a hamlet and a city, possesses at least one church, which allows us to distinguish it from the hamlets. Villages Most of the settlements identified as ‘villages’ are located on or around the Jebel al-‘Ala (Fig. 1). Very few of them have been found with certainty in the Jebel al-Hass. Evidence for the presence of churches are very scarce if not totally absent from previous publications and, as mentioned above, the last survey did not focus on this upland. However, to connect pieces of scattered data, village organization and development tend to vary greatly according their location on the different basalt plateaus. Some are enclosed by surrounding walls; others appear to possess a more impressive building that can tentatively be described as a ‘fortlet’. Some might also be endowed with a kind of atypical construction belonging neither to a type of housing nor to a place of worship. These constructions sometimes use unusual materials, or have uncommon functions occasionally specified by inscriptions. Fig. 5: Village of Rasm ar-Rbeyt (Mouterde & Poidebard 1945, p. 51) Fig. 6: Settlement of Zebed (Mouterde & Poidebard 1945, p. 88) Fig. 7: Village of Rasm al-Hajal (Mouterde & Poidebard 1945, p. 99)

‘Fortlets’ The so-called ‘fortlets’ can be encountered in a few villages (6) of the Jebel al-Hass and Jebel Shbeyt, but none of Roman-Byzantine date have yet been identified in the Jebel al-‘Ala. The fortresses hypothetically listed for that jebel (Halban, Tamak) belong instead to earlier periods. Yet this construction,

whether Roman or Byzantine, appears in areas further south, namely in the Jebel Bal’as (Khirbet ad-Dawsa). Built upon and around the basaltic mesas, this type of construction shows the same quadrangular plan as houses and mud-brick wings are added to each side of a courtyard. Nevertheless the ‘fortlet’ is obviously much more impressive than houses or even churches: the mud-brick mounds are much higher than others, and clearly the size of the buildings cannot be compared to that of constructions in the village. A few of the ‘fortlets’ are sometimes located in the village centre (2 of the 6 listed); some are to be found in the periphery (4 of the 6 recorded). The ‘fortlets’ of Mu’allaq and Rasm al-Hajal are separated from the main settlement by a wadi (Figs. 10-11, in both cases, the ‘fortlet’ is one of the buildings located on the south bank of the wadi, if not the only one). Moreover, if we exclude the case of Rasm al-Ahmar, ‘fortlets’ established near the village limits appear to be deeply associated with various agricultural structures: Fig. 8: Rasm al-Hajal, wall flanking the main access to village

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Surrounding walls The only city in the whole area under discussion, Anasartha, was surrounded by a basalt wall with doors and reinforced by square towers. The same features may be found, with some variations, in a few villages among the largest ones. Only two villages in the Jebel al-‘Ala were surrounded by a wall: Qasr al-Mharram, whose enclosure fortification includes towers and is dated by inscription to 570; and Halban, where the wall surrounds some 30 ha. It is very likely that some other villages possessed the same feature, but the available data does not permit further discussion for the Jebel al-‘Ala. At the foot of the Jebel al-Hass, one settlement alone was enclosed with a surrounding wall. In the village of Rasm ar-Rbeyt, in accordance with the architectural traditions of the area, the enclosure wall was built of mud bricks laid upon a partly reused basalt foundation, as indicated by trenches (Fig. 5). Two villages in the Jebel Shbeyt possess a surrounding wall: firstly, Zebed, clearly the most important nucleated settlement of that mesa, located at the bottom of a valley (Fig. 6); secondly Rasm al-Hajal, also situated in a valley. The surrounding wall of Zebed was built like that traced at Rasm ar-Rbeyt, whereas Rasm al-Hajal was isolated from downstream by a quite complex system of intersecting walls, flanking the access to the village (Fig. 7). Made only of heavy basalt pebbles or laid blocks, without any mud-brick superstructure, those walls were much larger and higher than the stone foundations of houses (Fig. 8). However strange they may look, they reveal a boundary between the settlement and the cultivated area, even though this might be the consequence of stones being removed from fields downstream. Thus one of the paths, flanked by north-south walls, marks out a border between those two separate areas of the settlement. Speaking of an ‘enclosure wall’ may thus seem excessive, yet, as in the above-mentioned examples, if we exclude those with towers, the aim of this pattern distinguishes limits within the settlement between the housing and agrarian areas rather than providing an effective military fortification, which could not be much more than an elementary protection.

Fig. 9: Carved basalt stone in the village of Twall Dabaghein 232

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enclosures on the lower part of the slopes (Mu’allaq, Rasm al-Hajal), terracing fields (at Rasm al-Hajal), or plots of land presumably used as fields or groves (Dreyb al-Wawi, cf. Fig. 12). Inside three of the six ‘fortlets’, a church was built, in all likelihood a short while after the construction of the ‘fortlet’ itself. At Rasm al-Ahmar, the church seems to be standing alone, whereas at Zebed (Fig. 16) and Mu’allaq, a tomb was erected nearby, inside the ‘fortlet’. A fourth settlement might have possessed a church: at Rasm ar-Rbeyt, in the centre of a large building, one can find tiles, baked brick, pieces of marble, gypsum (used as window pane), and painted coating, all of which are elements usually found in a religious building. In three cases (Mu’allaq, Dreyb al-Wawi and Rasm ar-Rbeyt), the ‘fortlets’ possess some unusual, namely military, features. The mud-brick superstructures at Mu’allaq and Dreyb al-Wawi seem to have been built on a basalt glacis. Moreover, at Dreyb al-Wawi as well as at Zebed, a square tower flanks each corner of the construction (Fig. 12). At Rasm ar-Rbeyt, a ditch was dug around the ‘fortlet’; another noteworthy feature is the short esplanade on the north side of the building (Fig. 5). The primary purpose of these ‘fortlets’ requires further examination. We can only assume that they were originally military outposts, as indicated by certain defensive features observable in some. In that case, as they occupied the central part of the village and were included in the surrounding walls (Zebed, Fig. 6; Rasm ar-Rbeyt, Fig. 5), they were arguably at the very origins of the settlement. This is especially obvious in the case of Rasm ar-Rbeyt’s ‘fortlet’, where the rubble (limestone) mined in the ditch was partly reused in the village’s surrounding wall masonry, mainly made of basalt and mud brick. In that case, the ‘fortlet’ and the settlement’s surrounding wall appear to be contemporaneous, and both go back to the foundation of the village. Other ‘fortlets’, though built on the periphery of the settlement, may have acted as a focal point around which the village began to expand. When not located in a central position, as mentioned above, those ‘fortlets’ seem to be connected with several agricultural structures; this easily fits in with the hypothesis of a military post. Association with a church at the centre of a building posits the presence of a religious complex, or, more tentatively, of a village monastery. In any case, it is highly probable that the church did not initially occupy the middle of the ‘fortlet’. As one can see in the plan of Zebed (Fig. 16), the orientation of the ‘fortlet’ itself and that of the whole church are slightly dissimilar, which could indicate that, originally, the two buildings

Fig. 10: Settlement of Mu’allaq, (Mouterde & Poidebard 1945, p. 41). Fig. 11: Plan of the village of Rasm al-Hajal (made with a GPS by Rivoal & Vigouroux). Fig. 12: Dreyb al-Wawi, ‘Fortlet’ and associated plots (Photo by Y. Guichard)

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Earthen Domes and Habitats Fig. 13: Carved basalt stone from the village of Twall Dabaghein Fig. 14: Carved basalt stone from the village of Twall Dabaghein

were not planned together. It could therefore be surmised that the original military function of most of these ‘fortlets’ evolved and became religious or even monastic. However, in other areas, for instance in the settlement of AlAndarin, churches are surrounded by walls. Further examination in the field is therefore necessary to solve the issue of the initial function of ‘fortlets’. Atypical buildings Some previously mentioned buildings cannot be linked to either domestic purposes or to devotional. A few of them have been identified in the last re-

connaissance, as well as during the initial surveys. In the 1950s, in the village of Rasm ar-Rbeyt, a large construction, exclusively built of basalt and showing the same roofing technique as in southern Syria, was described by Antoine Poidebard and René Mouterde (Mouterde & Poidebard 1945, pp. 80-81). Although during the last survey it was no longer possible to trace that building (all construction materials having since been stolen), its purpose was, in all likelihood, quite different from other buildings identified in common villages. It is even possible that the ‘basalt building’ already mentioned by Antoine Poidebard and René Mouterde still visible at Rasm al-Hajal (which unfortunately will probably not survive for long), much resembles the one at Rasm ar-Rbeyt. At Rasm al-Hajal, the ‘basalt building’ bears an inscription referring to ‘Stephen’, mentioned also in the oratory text (Jalabert & Mouterde 1939, p. 320), and the same name also appears at Rasm ar-Rbeyt, this time associated with baths dated A.D. 530 (Jalabert & Mouterde 1939, p. 333). There is obviously a striking similarity between those two villages, if not a special link. Both contain a ‘basalt building’, and in both of them, ‘Stephen’ appears as a prominent individual. Moreover, if the presence of baths is attested by epigraphy at Rasm ar-Rbeyt, chances are that Rasm al-Hajal also had one. In fact, some fifty meters east of the ‘basalt building’, I have recognized three rooms, all belonging to the same construction (as shown by the baked-brick masonry on basalt foundations), recently unearthed by looters. The first room, of rectangular shape, is entirely covered by a barrel vault; the second bears many resemblances to a vestibule with at least four doors and plastered walls. Finally, the third room includes a small apse (Fig. 4), oriented not eastwards, which excludes any religious purpose, but fits in perfectly with bath installations encountered in Syria, particularly at al-Andarin, being the nearest. Those scarcely attested atypical constructions are especially significant for the study of central Syrian villages since they actually provide evidence that those settlements cannot be seen as simple clusters of crude peasants. In some of those villages – and the examples above do not take into consideration the largest clustered settlements in the neighborhood of the basalt mesas – some ‘urban’ aspirations, if not facilities, are particularly noteworthy. Circulation networks Street networks within villages can only be examined in a very few cases, exclusively in the Jebel al-Hass and the Jebel Shbeyt. Old aerial photographs provide some information, but mud-brick architecture can obliterate oth-

Fig. 15: Carved basalt stone from the village of Twall Dabaghein

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Citadel of Zebed earthen visible walls basalt walls hypothesized walls 0

Fig. 16: Zebed, Plan of the ‘fortlet’, with the church and the tomb (Mouterde & Poidebard 1945, plan 6)

erwise apparent passageways. Hopefully, the general rule was precisely to bound passageways with walls on either side, those specifically designed to mark paths, or built as part of houses and enclosures. Some scholars have spoken of orthogonal networks and regular housing layouts; even though pathways were actually deliberately created. To assume that an orthogonal plan oversaw the creation of the village seems excessive. On aerial photographs of Zebed taken in the 1950s, a network of paths clearly appears. Sometimes bounded with low basalt walls, lanes are also limited by enclosures and house walls, as well as by some walls defining strange empty spaces. Nevertheless, until excavations are undertaken, we have scarcely any idea whether or not these streets were paved, or whether they were related to particular arrangements. In all probability, they consisted of minimal earth pathway. Aerial photographs enable one to distinguish a network of ways at Rasm al-Hajal (Figs. 7-11); outside the village itself pathways lead from the plateau and foothills deep into the settlement. With walls on either side high enough to resemble enclosures, these large roads enter the village and their features immediately change. The pathways turn into narrower alleys, only bordered by houses or enclosure walls. Nevertheless, as rustic as those pathways appear to be, there can be no doubt that these were a real network, since, as opposed to what can be seen in other regions, these passages cross the village from one end to the other. They do not disappear when they reach a house but simply bypass it and go on until the whole village has been dis-

sected; they also appear much more coordinated than in other areas, particularly in the Limestone Plateau. Unlike at Zebed and Rasm al-Hajal, aerial photographs of Mu’allaq do not make it possible to observe a network of alleys. Yet the layout of houses appears to be especially regular: they seem to be ordered in several rows, and some pathways follow this pattern (at least in some areas). The apparent consistency of street networks in villages is a specific characteristic of this part of Syria. This quite coherent system of pathways makes the entire region relatively different from other parts of Syria, and above all, from the Limestone Plateau where circulation networks and also the layout of houses seem to be much more random. Hamlets Generally, most clustered settlements listed in the Jebel al-‘Ala can be associated with a church either partly preserved or deduced from architectural remains (chancel posts, reliquary, etc.). These sites have to be considered villages. To find hamlets one has to look at the Jebel Shbeyt. Even though some must have existed in the Jebel al-Hass, this category of sites has not been surveyed as systematically as in the Jebel Shbeyt, either during the last survey or during the previous ones. Hamlets recorded in the Jebel Shbeyt are located either on the plateau, on the foothills, or at the bottom of valleys (Fig. 1). One can distinguish between two main types of hamlets: The first category consists of a close association of a few buildings. They are built adjacent to one another and thus reflect natural development of the family over several generations and the gradual expansion of the initial farmhouse (Jinqaseh Batush 2, Fig. 17). The second type of hamlet consists of an assemblage of scattered constructions, sometimes separated from one another by a space of more than 50 m, without any structures in between. Some large enclosures, whose sizes vary greatly, may be associated to the dwellings (Fig. 18). Scattered Units Mainly noticed in the Jebel Shbeyt due to the disparity of data between the Jebel al-Hass and the Jebel Shbeyt, it seems rather logical that, as a consequence of greater climatic constraints, a larger number of isolated settlements developed around this plateau. They are of several types: some may have existed for worship, while others may simply have been isolated farmhouses.

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building wall enclosure wall undetermined wall mud brick mound plundered area posterior wall

Fig. 17: Plan of the hamlet of Jinqaseh Batush 2 (made with a GPS, Rivoal & Vigouroux). Fig. 18: Plan of the hamlet of Tuwehineh 4 (made with a GPS, Rivoal, E. Vigouroux).

Mouterde & Poidebard, can be found at Qasr Leben, 5 km north of this last settlement (Mouterde & Poidebard 1945, p. 168). Within a large enclosure, the main mud-brick building included a small basalt construction, with the orientation of a church. The slopes to the east are terraced, from the edge of the jebel to the building itself. This settlement might very well have been a monastery, although these scholars had not ventured such a hypothesis. Finally, on the same side of the jebel, though founded at the bottom of a valley, Tuwehineh 3 is undoubtedly a monastery. The receptacle of a shrine was found in situ along the eastern wall of the building. Its lid lay a few meters to the east, and was pierced with a hole, which clearly points to a sacrificial function. The building itself, even though very large (more than 50 m in length), looks like a farmhouse from the outside, but the finds retrieved are not those of a simple farmstead. The construction is the centre of a system of enclosures, void of stones and connected with cisterns.

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Monasteries A few other buildings have been interpreted as being monasteries, with various degrees of certainty. They should be divided into two categories: the first includes constructions on promontories, whereas the second type takes into account buildings essentially established at the bottom of valleys. Belonging to the first group of presumed monasteries, Ramleh, situated at the southern edge of the Jebel al-Hass, is largely hidden under a modern construction and a cemetery. The contemporary building reuses column shafts, capitals, pieces of cornice marked by a chrism, and some numerous tiles taken from Byzantine edifices. The cluster of Byzantine buildings was associated with a terrace system built lower down against the slopes. The whole surface of the upper terrace is strewn with tesserae, baked bricks and tiles, and some small square chambers around one or more courtyards have been noted. This settlement has been interpreted as a monastery because of its situation, inappropriate for a farmhouse. Moreover, the architectural elements scattered all around seem to point in the same direction. Thus, even if we cannot be certain that a monastery once existed at Ramleh, the probabilities are nonetheless quite high. The case of Tuwehineh 1 appears to be very similar, as it belongs to the same kind of construction: terraces and enclosures were built against the slope of a promontory where a building was erected, completely covered by a small modern construction. The summit of the promontory formed an esplanade where both a sarcophagus and its lid were found. This last element weighs most heavily in favor of a monastery, although there is still no absolute certainty. Another group of buildings, taking advantage of similar locations, was previously considered a possible monastery. This site (Tell Drehem 1) includes three consecutive enclosure walls, surrounding a courtyard in the middle of which stands a strange cruciform construction, described by some scholars as a church (Mouterde & Poidebard 1945, p. 171; Haase 1982, p. 71). Terraces climb the promontoryâ&#x20AC;&#x2122;s slopes. Some other buildings in locations significantly different from the previous ones can safely be interpreted as serving monastic purposes. Tell Drehem 3, for instance, is situated in the eastern foothills of the Jebel Shbeyt. A Syriac inscription mentions an archimandrite, the head of a monastery (Mouterde & Poidebard 1945, p. 227). The building itself, surrounded by enclosures, is built in mud brick. Another very similar construction, whose existence has been reported by

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Farmhouses More representative of scattered settlements, farmhouses are numerous and all follow the same model. Between two and four wings border the sides of a courtyard, therefore forming the centre of the farmstead. Some enclosures, which sometimes completely surround the building, are always associated with the farm, as are terraces and some smaller arrangements on the hillside. However, and most importantly, farmhouses are always located in valleys, understandably close to areas of high agricultural potential: soils are deeper in valleys, and water is more available, at least at certain times of the year, due to neighboring wadis. All settlements, whether clustered or scattered, are intrinsically connected with the milieu on which they depend. Accordingly, the smallest changes in the environment bring about various degrees of adjustments in subsistence strategies. Agricultural structures There is currently no way of studying in detail the agricultural practices of the Jebel al-‘Ala. Existing cultivated areas are too widespread for various ancient organizational arrangements (plot distribution, surface of soil devoted to gardens, animal husbandry, annual crops) to be traceable. We can only presume that cereals must have grown as rainfed crops (wheat, barley), and that gardening was in all likelihood restricted to the vicinity of villages. Some holes, dug into calcareous crust sealing soils, were clearly used for arboriculture, allowing trees to have direct access to soils, and the calcareous crust prevented water from evaporating. Fortunately, far more data is available from the easternmost uplands, even if many questions remain unanswered. First of all, remnants of agricultural structures can be observed everywhere (on plateaus, slopes and valleys). Some of the main nucleated settlements discussed above provide good examples of the variety of structures well adapted to their local environmental setting. Firstly, the summit of plateaus was used for cultivation, as proven by the numerous outstretched plots. Some of the latter, particularly around Dreyb al-Wawi (Fig. 12), have been seen as tree groves, since the stone heaps were considered holes where trees were planted (conclusion based on aerial photography) (Rigot 2003, p. 119). There can be no doubt, however, once the ground is surveyed: those ‘holes’ are piled up stones, clearance from fields.

Rather than having been used for arboriculture, these plots were more probably for rainfed agriculture, generally the cultivation of barley. Dreyb al-Wawi, located at the very beginning of a valley, may have had sufficiently deep and humid soils to allow for the growing of wheat. This, however, would be a geographical exception. For villages founded deep within valleys, for instance at Zebed, Mu’allaq, and Rasm al-Hajal, some terraced fields were built on the upper half of slopes, running down the hillside. They might have been for olive tree or vineyard cultivation. In support of this hypothesis, it should be mentioned that elements of presses have been found, for instance at Mu’allaq, Rasm ar-Rbeyt (crusher/olive mill and press orthostats). Enclosures, sometimes also supported by terrace walls, can run from the highest cultivated terrace down to the foot of hills (Rasm al-Hajal). They can also be observed in close association with villages, clustering on the edges, in the vicinity or within dwelling areas (Fig. 11). Further down the valley, in two villages (Rasm al-Hajal and Mu’allaq Figs. 7-10), as well as higher up at Zebed, a different kind of enclosure, more regular in shape, smaller, and adjacent to one another, can be distinguished. It borders the wadi bed or is framed by two wadis (at Rasm al-Hajal). In these cases, enclosures must have been irrigated and probably worked as gardens. Those plots are grouped within a larger enclosure at Rasm al-Hajal, something which fits very well with the current shape of gardens: closer to dwellings and more or less protected by a rough wall in order to prevent the incursion of livestock. Hydraulic features Apart from wells and springs available in valleys and cisterns dug on plateau summits, some specific installations must have optimized crop yields and provided some water to settlements. Nevertheless, qanats are not as frequent as expected, since only a few have been recorded. One, in the hamlet of Al-Hammam, at the southern end of the Jebel Shbeyt, is supposed to have once supplied the city of Anasartha some 17 km to the northwest (this is known from an inscription, Mouterde & Poidebard 1945); other shorter ones also watered this urban centre. Another, built in a valley, presumably reached Rasm al-Ahmar, on the northern foothill of the Jebel Shbeyt. A qanat has also been identified in the Al-Awina valley, on the western side of the Jebel Shbeyt, but does not seem to be linked to any settlement at its outlet. Open channels can be observed in at least two hamlets: at Shellaleh Srir, a channel

Animal husbandry Stalling The only data available concerning animal husbandry in the Jebel al-â&#x20AC;&#x2DC;Ala can be deduced from house plans. It appears that cattle breeding in this area implied stalling: ground floor plans show a series of small pillars between which troughs were inserted. This kind of installation recalls the plan used in houses of the Limestone Plateau and in southern Syria (the Hauran). The practice of stalling was probably linked to the breeding of cows and donkeys. This does not, however, entirely exclude sheep husbandry, which left far fewer traces than cattle breeding, since sheep did not necessarily need housing. Pastoralism In the Jebel al-Hass and the Jebel Shbeyt, stalling has not left any traces, whereas pastoralism (essentially sheep husbandry) is clearly everywhere. This type of breeding, as is still the case nowadays, can be easily deduced from the frequency of enclosures inside settlements (Fig. 11, 18), farmhouses and monasteries. The spaces enclosed, almost systematically connected to dwellings, have been carefully cleared of stones. Their location, compared to that of wadis, do not allow us to see them as gardens, given the complexity implied by an irrigation system in such a position. Moreover, as in the case of Rasm al-Hajal and Muâ&#x20AC;&#x2122;allaq, gardens have been already identified. These enclosures can be associated with cisterns, a characteristic of penning. Basalt troughs are also very common. Most of these enclosures, in nucleated settlements or on scattered sites, have almost all been systematically reused by circular stone pens, which shows that they were perfectly designed for this purpose originally. On plateaus, rather smaller settlements are associated with large enclosures and cisterns. Those observed in some nucleated settlements have since been reoccupied: the largest ones have been divided into several plots separated by crude walls. Although these upland settlements were linked to plots, cave shelters on the other hand clearly point to pastoralism. More generally, it seems that the Jebel al-Hass and the Jebel Shbeyt were always appreciated by shepherds and the frequency of circular stone pens, attributable to nomadic or semi-nomadic populations, whether on plateaus

Fig. 19: Basalt stone foundations in Rasm Hamd

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lead from a short qanat and forwarded the water to the settlement. Another one collected spring water upstream from Muâ&#x20AC;&#x2122;allaq and brought it to the village.

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or in valley floors, next to cisterns or wadis, testify to their continuous presence. These circular pens should probably be attributed to nomadic or seminomadic shepherds. Some of them date back to before the Byzantine period, while others were clearly built later. Without any doubt, pastoralism is an aspect of every settlement on the plateau. Cultivation and sheep husbandry are two interconnected activities in this area of hardly sufficient rainfall, with the constant uncertainty of crop yields as a result of the large variability in precipitation levels. Pastoralism, therefore, emerges as an essential economic complement. Conclusion Following the reexamination of all data from the three basalt plateaus, and while taking into consideration the current disparity in available information, one can observe that settlement features vary slightly from one plateau to another. First of all, the nature of occupation itself changes (Fig. 1). The Jebel al-‘Ala mainly brings together settlements which for the most part possess one or several churches. In this anticline, villages appear to dominate settlement patterns. The situation in the Jebel al-Hass is not very different from that of the Jebel al-‘Ala: there too, villages seem to be the most significant form of settlement. Villages can also be found in the Jebel Shbeyt, though hamlets and scattered habitat prevail over the entire range. Even if hamlets are more numerous than villages, scattered sites are paramount, since they dominate the plateau and the eastern foothills, locations where several monasteries were observed. Moreover, differences between settlement patterns and subsistence strategies are easy to make between the Jebel al-‘Ala on the one hand and the Jebel al-Hass and Jebel Shbeyt on the other. In the Jebel al-‘Ala, occupation seems to be undifferentiated and covers the entire plateau. This can easily be explained by the relative absence of climatic constraints. Thus, seeking the most favorable place to settle does not appear as essential as in the eastern ranges. Further east, for instance in the Jebel al-Hass, settlements seem to be mainly restricted to valleys, especially villages needing larger soils and more significant water resources. This trend appears to be stronger in the Jebel Shbeyt, where each settlement with an agricultural function (both nucleated settlements and scattered habitat) is in fact located at the bottom of a valley.

In the latter jebel, however, the economy is not only based upon crop cultivation, but appears to be diversified and clearly includes animal husbandry. Settlements can, therefore, equally be established upon plateaus or at the foot of hills where soils are thinner and water resources more scarce than elsewhere. To briefly conclude, it must be pointed out that these basalt lands, especially the ones furthest to the east, show features different from other areas of Syria, where villages and rural life have already been studied in detail. Nevertheless one finds confirmation of a hypothesis first expressed by Georges Tchalenko in his essential monograph (Tchalenko 1953, p. 2): results yielded in the Limestone Plateau as well as in southern Syria (Hauran) cannot be applied to other regions. Syria is made up of a patchwork of environments and settlements, mostly Byzantine. Populations took into account the specific milieu, they then developed adaptation strategies that had a deep impact upon settlement patterns. As a consequence, village organization in the Jebel al-Hass and the Jebel Shbeyt shows important divergences with that observed in other areas: streets are attested, and so are enclosure walls, though both belonged not to cities but to villages. List of References Butler, H.C. 1903, ‘Publications of an American Archaeological Expedition to Syria to 18991900’, Architecture and Others Arts, 2, New York. Butler, H.C. 1920, ‘Syria, Publications of the Princeton University Archaeological Expeditions to Syria in 1904-1905 and 1909’, Architecture, 2, Section B, Northern Syria, Leyden. Gatier, P.-L. 2001, ‘Grande ou petite Syrie seconde ? Pour une géographie historique de la Syrie intérieure protobyzantine’, Geyer, B. (ed.), Conquête de la steppe et appropriation des terres sur les marges du croissant fertile, Travaux de la Maison de l’Orient, 36, Lyon, pp. 91-109. Geyer, B. (ed) 2001, Conquête de la steppe et appropriation des terres sur les marges du croissant fertile, Lyon, Travaux de la Maison de l’Orient, 36. Jaubert, R. & Geyer, B. (eds) 2006, Les marges arides du croissant fertile. Peuplements, exploitation et contrôle des ressources en Syrie du Nord, Travaux de la Maison de l’Orient, 43, Lyon. Haase, C.-P. 1983, ‘Ein archäologischer Survey im Gabal Sbet und im Gabal al-Ahass’, Damaszener Mitteilungen, 1, pp. 69-76. Jalabert, L. & Mouterde, R. 1939, Inscriptions grecques et latines de la Syrie, 2, Chalcidique et Antiochène, Bibliothèque Archéologique et Historique, 22, Paris. Lassus, J., 1935, Inventaire archéologique de la région au nord-est de Hama, 2 vol., Beyrouth (Documents d’Etudes Orientales, 4). Mouterde, R. and Poidebard, A., 1945, Le limes de Chalcis: organisation de la steppe en HauteSyrie romaine, 2 vol., Paris (Bibliothèque Archéologique et Historique, 38). Rigot, J.-B. 2003, Environnement naturel et occupation du sol dans le bassin-versant du lac Jabbûl (Syrie du Nord) à l’Holocène, thèse de doctorat en Géographie, Lyon, Université Lumière Lyon 2. Tchalenko, G. 1953-1958, Villages antiques de la Syrie du Nord, le massif du Bélus à l’époque romaine, 3 vol., Paris.

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We present an essential glossary of terms related to earthen architecture in northern Syria. The glossary is the outcome of a filed research on Syrian mud architecture carried out in collaboration with the General Directorate of Antiquities and Museums. The aim is to underline the various local earthen architectural terms and traditions of the country, focusing on those terms used in the northwest and on some terms used in rural building culture. During the on-site research and documentation focusing on the Syrian heritage of earthen architecture especially in the region of Aleppo, we faced the question of words (with their transcription) associated with elements of this special cultural landscape. We decided to prepare a primary glossary of terms describing this architectural culture where terms are described, summarized briefly and illustrated in order to allow a synthetic understanding of various earthen building cultures and terms in five main regions occupying the northern parts of Syria, extending from east to west in the following order: Al-Hasakah (Al-Qameshli), Ar-Raqqah, Aleppo, Idlib and Hama (Salamiyah) region which is considered as a continuity of the Idlib and Aleppo plains. We found common terms quite widespread across the entire north of Syria, in near classic Arabic, such as: Al-Baedar, Asas, Bab, Attabeh, Be’er, Baet AlMuneh, Dar, Daraj, Ewan, Dekkeh, Fallah, Ellea, Gedar, Gurpha, Hajar Hammam, Haush, Hazeera, Hawwara, Kateph, Kels, Kashab barm, Lebn, Mastaba, Madafa, Madena, Marhad, Masjed, Matbakh, Matban, Mauqed, Memarje, Mezrab, Muallem, Mustauda’ Hatab, Nafeza, Najafeh, Qaleb, Qarea, Qarmeed, Qaus, Qefl, Qunn, Qesh, Qubba, Raff, Saha, Saqf, Sebat, Shurfa, Sur, Taqa, Tannur, Tebn, Teen, Teena, Turab, Zuqaq. Other terms are used in the northwest of Syria (Aleppo and Idlib regions), such as: Al-Fejje or Al-Kuara, Hakura, Zribeh, Khabia, Kehla, Muzarrek, Khum, Zreeqa. There are also some specific terms used in their own regions and not known elsewhere, such as: Dewar (Idlib),Qubbia (Hama), Tasee’ (Hama, and Ar-

Directorate of Antiquities and Museums of Aleppo, Syria

Saverio Mecca

University of Florence, Italy

Raqqah), Oda (Aleppo, Idlib), Dewan (Ar-Raqqah), Medmak (with different meanings between Aleppo and Ar-Raqqah), Earthen Architectural Terms Earthen houses in Syria do not differ very much in their rural nature and their urban features from rural houses, for this reason we grouped together terms used in earthen architectural culture and rural buildings, organized in alphabetical order as follows.

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Glossary of earthen architectural terms in Syria

Mohammed Dello

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Al-Baedar A place where fruit is collected to be ingathered, this term is used in earthen architecture villages and rural contexts.

Asas A base composed of mud and small stones. Sometimes lower parts of earthen walls are constructed with stone, and are thereby well protected from the rain.

Fig. 1: Al-Baedar, Idlib (Giobas)

Aamoud (Amuod) A column, rarely used in domed houses or mud architecture, except occasionally to support the roofs of porches.

Baet Al-Muna (Al-Fejjeh) A store room, used to keep food and fruit for winter; sometimes we do not see it as a separate room but as a section called a ‘Kuara’ in the living room, having small holes in the lower part to place food.

Fig. 5: Baet Al-Muna, Idlib region. Fig. 3: Asas, Aleppo (Habbuba)

Bab A door or portal, often made of timber, sometimes we find a stone nearby to extend washed clothes on.

Be’er (Giubb, Gialeeb) A well sometimes with the upper part built from stone or from mud and stone.

Aresheh Architectural space similar to ‘Ewan’, usually delimited from three or (rarely) two directions, mostly covered with climbing plants (grapes, etc.). Attabeh A delimited part of the floor, on a lower level than the room, at the door used to deposit shoes, often we find a pot of water (Al-Khabia) nearby, sometimes used by poorer people for bathing purposes.

Fig. 2: Attabeh, Idlib (Mardeekh)

Fig. 6: Be’er, South Aleppo.

Dar A house or home, which can be built from mud or stone or both.

Fig. 4: Bab, South Aleppo.

Fig. 7: Dar, South Aleppo

Daraj Stairs constructed of stone or mud.

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Fig. 10: Dewar, earth, Meksar Shamlei, (Hama)

Fig. 12: Elleah, Idlib (Giobas)

Fallah (Karaui) An inhabitant of a village (Karea), building his earthen house by himself with the help of his parents or neighbors, hiring a mason (Memar or Muallem) for the building of mud domes.

Fig. 8: Daraj, Aleppo (Saint Simon)

Dekkeh (Mastaba) Interior or exterior bench, often built of mud and stone, plastered with earthen or cement mortar, large or small.

Fig. 13, Fallah, Hama (Salamiyah) Fig. 9: Dekkeh, Ar-Raqqah

Dewar A earthen construction technique used in Syria, very similar to the cob technique, made by building an earthen dome with loam courses, two each day until the entire dome has been completed: one in the morning and a second in the evening to permit good drying.

Fig. 11: Dewar, earth and stones, South Aleppo

Ewan (Sebat) Delimited space with three earthen walls, often opened from one direction toward west, used always to repose or to receive visitors, but not common in all rural houses where it is called â&#x20AC;&#x2DC;Sebatâ&#x20AC;&#x2122;.

Elleah Large room situated on the first floor or higher level, built from mud or stone particularly used in summer or for guests.

Gedar (Haet) A wall, may be constructed by several techniques of mud architecture: earthen bricks (adobe), rammed earth, mud-stone, cob, etc. It can be built with many different methods.

Fig. 14: Gedar, Aleppo (Habbuba).

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Gurpha A room, may be for guests (Deuf), living (Mae’sha), sleeping (Naum), this room may be domed or nondomed, and sometimes it has multiple functions at the same time (living, sleeping, etc.).

Fig. 17: Hakura, South Alepp

Fig. 19: Haush, South Aleppo

Hammam A bathroom, has many types of roofs: traditional (flat) and, rarely, earthen domes which have small holes.

Hawwara A solution of white fragile stone dipped in water for three days until it emulsifies, sprinkled then on mud walls as a form of plaster, sometimes used as a first layer under the lime plaster to strengthen earthen surfaces.

Fig. 15: Gurpha, Ar-Raqqah

Hajar Stones, used in different elements of mud houses (base, wall, etc.), their shape and volume depends on construction technique (mud-stone, etc.), there are two main types of it used in mud houses: basaltic called ‘Hajar Bazelti’, and calcareous called ‘Hajar Kelsi’.

Fig. 20: Hawwara, South Aleppo

Hazera ‘Qabu’ A room where animals are kept, in some regions it is called ‘Qabu’ or ‘Zribeh’. Fig. 18: Hammam, South Aleppo

Fig. 16: Hajar, Aleppo (S. Simone)

Hakura (Bustan) Interior garden surrounded by boundaries, situated in front of the earthen rooms or behind them.

Haush (Sahn) A space exists in mud or rural houses open to sky surrounded by boundaries or walls which protect the house from animals and strangers, sometimes there is an independent ‘haush’ used to lodge animals situated near a stable called ‘Hazera’, ‘Zribeh’ or ‘Qabu’. Fig. 21: Hazera, Idlib (Kelli)

Khabia (Mzammaleh) A water-pot, usually made of terracotta called ‘Fakhar’ and situated near the room door, its loam mixture (before being burnt) is composed of: three parts earth, two parts finely sieved earth and fine straw or animal hair. This mixture will be laid on a slow fire, protected from the effect of direct fire by treating its surface with animal dung called ‘Fashfash’.

Fig. 22: Khabia, Aleppo (Saint Simon)

Ketf Constructive element or buttress integrated into earthen walls to carry earthen domes.

Fig. 24: Khashab Barm, Aleppo (Habbuba)

Khashab Tabak Flat wood used in wooden traditional roofs, set on ‘Khashab barm’.

Fig. 27: Ketf, Ar-Raqqah

Kehla (Malat) Mortar Joint, the layer of mortar between mud blocks (See Fig. 27).

Fig. 25: Khashab Tabak, Al-Qameshli

Khezana Gedaria A rectangular or square hollowed shape in mud walls, used to store many things depending on the room: bedroom (cushions, covers, etc.), kitchen (dishes, spoons, etc.).

Fig. 28: Kehla, Al-Qameshli

Fig. 26: Khezana Gedaria, South Aleppo (Al-Wdehi)

Fig. 29: Kels, Idlib (Mardeekh)

Kels Lime, the procedure of mud wall painting is named ‘Taklees’. Sometimes people plaster the whole facade with lime plaster or only around the doors or windows.

Fig. 23: Fashfash, Idlib Region

Khashab Barm Trunks used to support a traditional roof. In crosssection always round, or nearly so.

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Hour Poplar, a type of wood used in covering mud houses with flat traditional roofs, this wood is inexpensive but not very resistant to weather effects.

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Jaez (Jisre) New idiom used in new architectural terms, related to cement elements more than mud and traditional architecture, meaning a horizontal structural element to load the roofs. In mud architecture and traditional roofs it represents the round trunks ‘Khashab Barm’ which carry the other layers of the roofs.

Matbakh Kitchen with earthen shelves.

Lebn Local name of sun-dried brick or ‘adobe’, it is called sometimes ‘lebn trab’ to distinguish it from stones ‘Hajar’ or cement blocks ‘Qarmeed’, its size varies regionally. Fig. 32: Matbakh, South Aleppo

Matban Sotre, for keeping straw. When it has a traditional flat roof, there is a hole in the ceiling named Af’a’a used to pour the straw through. Fig. 34: Mauqed, Idlib region

Fig. 30: Lebn, Hama (Salamiyah)

Madafa (Oda) A large room for guests, usually built for rich men or village chiefs called ‘Mukhtar’ or leaders ‘Agha’, built outside the house and often very rich in decoration.

Medmak A course of earthen blocks used in walls or in mud domes; it has a round shape in domes, earthen bricks situated horizontally in the conic domes, and inclined in the round. This term means an instrument to compact earth in other regions, such as Ar-Raqqah, while the same instrument is called ‘Duqmq’ in the region of Aleppo.

Madena City. There are some big cites in Syria that have examples of mud architecture. Marhad (Baet Al-mai) A toilet, rarely situated in the house, in many cases separated. Masjed Mosque built from mud or stone, without minarets in some mud villages.

Fig. 33: Matban, Idlib (Giobas)

Mauqed (Dfeeh, Kanun) Fireplace, situated in the middle of a mud room or at the corner, sometimes there is a simple open ‘mauqed’ in the kitchen for cooking.

Fig. 35: Medmak, South Aleppo Fig. 31: Masjed, Idlib (Giobas)

Mukhtar village chief. Mustauda’ Hatab Timber store, a place where people put wood for cooking or for storage in winter. Sometimes this place is used as a kitchen by poorer inhabitants, in other cases it is a very small store used particularly to provide the ‘Tannur’ earthen oven with wood.

Najafeh Lintel, covering doors and windows, generally made of wood.

Fig. 36: Memarje, South Aleppo

Mezrab Canal, extending some distance from a roof, made of iron or occasionally made of stone in richer houses.

Fig. 41: Najafeh, South Aleppo

Qaaleb Wooden module, into which loam mixture ‘Teena’ is poured to produce earthen bricks, with various dimensions. Fig. 39: Mustauda’ Hatab, Idlib Region

Muzarrek Plasterer. Usually this work is carried out by women in the tradition of mud architecture. Fig. 37: Mezrab, South Aleppo

Nafeza (Shubbak) Windows, having many shapes in mud architecture.

Muallem (Maalem) Expert mason, chief of builders who leads a group of ‘Memarje’, he is more skilled than others and specialist in dome construction or difficult constructive cases.

Fig. 42: Qaaleb, Al-Qameshli

Qarea Village, there are many villages in Syria that are completely built with earthen houses. Qarmeed Small fired bricks used in inclined roofs on mud houses, or cement blocks used in new buildings substituting mud houses.

Fig. 38: Muallem, South Aleppo.

Fig. 40: Nafeza, Aleppo (Habbuba)

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Couples et habitat

Memarje (Memar, Banna) A mason who builds in adobe or stone, in some regions he leaves his handprint as a signature at the end of construction.

Qubba Dome, built with adobe blocks, mud-stone or cob technique, having many shapes and may be true or false depending on its shape and courses.

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Earthen Domes and Habitats Fig. 43: Qarmeed, Idlib (Mardeekh)

Qasab A cane, used in some flat roofs to cover mud constructions, especially those called ‘Ewan’ or ‘Sebbat’ situated mostly near rivers or lakes.

Fig. 45: Qefl, Hama (Salamiyah)

Qunn (Khum) A place where hens are kept, it can be considered as a typical part of mud or rural houses. Fig. 48: Qubba, South Aleppo

Qaus (Qantara) An arch on doors or windows, or in a wall separating two domes or rooms; it can be constructed of stone or mud.

Qubbia Small earthen domes, used to keep lumber, to conserve fruit and food or to store straw.

Fig. 46: Qunn, Idlib (Mardeekh)

Qesh Long pieces of straw, always used with mud mixture and employed to produce adobe blocks. Straw is mostly used with mud plaster. Fig. 44: Qaus, Idlib (Mardeekh)

Qefl (Tantur, Antuuz) A stone at the top of a dome, usually placed on the final blocks which close the dome, having the structural functions of protecting the top of the dome and keeping all the courses together, with also an esthetic, traditional role. When a mason completes the dome structure he does not descend until he has received a tip from the owner.

Fig. 47: Qesh, Al-Qameshli

Fig. 49: Qubbia, Idlib (Giobas)

Saqf Ceiling, earthen houses have many forms, inclined (in one or two directions), flat or domed roofs.

Tall (Tell) A hill, in many cases can hide a village or an archeological site beneath, some earthen villages are at the foot of the hill. Taqa Holes in earthen walls, sometimes they open onto the exterior face of the wall (used as small narrow windows in this case), in another cases not extending into the wall depth and are used for placing food or small objects.

Fig. 50: Raff, Idlib (Mardeekh)

Saha (Fas-ha) Urban term meaning plaza or small square found in earthen villages. Sane’ (Agee) A person who works with a mason ‘memarje’ or ‘muallem’, sometimes making adobe.

Fig. 52: Saqf, Ar-Raqqah

Sebat Rectangular earthen room (called ‘ewan’ in some regions), opening on one part toward north because it is used in summer for repose or to receive guests, with benches (dekka), fireplace (mauqed) and waterpot (khabia). Shurfa (Riwak) Porch, a covered gallery which makes up the entire front elevation or a section of it, but not present in all Syrian earthen houses. Sur Mud boundary or wall, it is usually high enough to prevent animals or strangers from entering a house. It is not high enough for privacy, this role being less important than in the cities.

Fig. 51: Sane’, Al-Qameshli

Fig. 53: Sur, Al-Qameshli

Fig. 54: Taqa, South Aleppo

Tannur Traditional oven to bake bread. Women always construct it with a mixture composed of mud, terracotta and some local dried grasses, includes a large hole through which dough is inserted. Open skywards (horizontally) or vertically.

Fig. 55: Tannur, Rasm al Bugher

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Earthen Domes and Habitats

Raff Gypsum or mud shelf on earthen walls in houses, of many different shapes and figures, sometimes rich in decoration.

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Tebn Straw used with mud plaster or in earthen bricks.

Turab (Trab) Earth, suitable for construction when it has enough clay to be coherent and consistent. Syria has several colors of earth: red, orange, yellow, brown. Zreeka (Taseeâ&#x20AC;&#x2122;) Plaster, mud-straw mixture used as wall covering, in richer houses the plaster can be of lime.

Fig. 56: Tebn, Idlib (Giobas)

Teen Clay-mud, used in all construction techniques.

Fig. 59: Zreeqa, Idlib (Kelli)

Zukak (Darba) Urban term meaning alley, which in Syrian earthen villages are not asphalted. Fig. 57: Teen, Aleppo (Saint Simon)

Teena (Malat) Earthen mortar or mixture used to produce earthen bricks, to connect earthen blocks, or to plaster walls and surfaces.

Fig. 60: Zuqaq, Al-Qameshli

Fig. 58: Teena, Al-Qameshli

List of References Ali, A. 2002, Qura al-teen, Damascus. Ameen, M. 1983, Salamia Fe Khamsun Qarna. Mshallah, A. 2002, Al-Mantiqa Al-Gharbia Li-wilaliat Halab, Idlib fe Al-qarn al-sabe ashar, Damascus.

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An architectural analysis

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The context of dome villages The territory of the northern Syrian plains was for centuries a favourite place for tribes of nomadic and semi-sedentary herders of sheep and goats (Aurenche, 1984). It is a region of hills and plains, bordered by rivers during the rainy season and early spring, and is well suited to grazing. Although the Syrian lands were influenced by the passage of many tribes, the traditional rural society seems to be strongly influenced by its nomadic origins (Ghiyas, 1984). The villages of the arid margins of Syria were abandoned after the Mongol invasions of the 14th century that pushed the sedentary populations westward. The reoccupation by sedentary and semi-nomadic peoples began in the middle of the 19th century. Since 1848, the re-colonisation movement from which the present villages emerged was promoted by the Ottoman authorities to both reinforce their control of the arid margins and to increase agricultural production. In the region of Hama, the process of settlement was initiated by Ismaili and Alawite farmers, establishing villages in those sectors most favourable for agriculture. The less cultivable lands were progressively occupied by Bedouin families. In the province of Aleppo the population is mainly of Bedouin origin (Jaubert & Geyer, 2006). The Bedouin tribes were organized into small villages, preserving their traditional way of life based on an economy of subsistence and self-sufficiency. The villages were located near supplies of water at the foot of hills, often on the ruins of former Byzantine settlements. Because of the agrarian reforms of the early 1940s, another substantial part of the tribes of Bedouin origin moved from the nomadic lifestyle to the sedentary, and their pastoral economy became agricultural. The developments of these years modified relationship patterns among group members; as a consequence, those cultural features once solid and typifying became more transient (Savioli, 2006).

University of Florence, Italy

Emmanuelle Devaux

University of LiĂ¨ge, Belgium

The transition from a nomadic life and culture to a settled way of life undoubtedly also influenced the abandonment of the villages for the cities, where commerce and opportunities were more favourable. Over time the villagers increasingly interacted with sedentary and city life, while still recognizing their Bedouin origins and their lineage, membership of a tribe and the authority of tribal leaders. Location of dome villages The architecture of earthen corbelled domes is visible in many inhabited villages in the regions of Aleppo, Hama, and eastwards along the Euphrates Fig. 1: Syrian region. The highlighted area denotes where dome villages are more widespread

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The urban morphology of dome villages

Letizia Dipasquale

scape with hills. The villages of this study are located in three different areas to the south of Aleppo city, in addition to the village Tayara established in the suburbs. The first area is the Lake Khanasser, southeast of Aleppo including the villages of Oum Aamoud Kebir, Oum Aamoud Seghir, Rasm Hamad, Fejdane, Er Raheb and Rbaiaa. The second area, located a little further west and near lake al-Assad, is formed by the village of Joub Maadi and Rasm al Bougher. The third, east of Hama, is represented by the village of Cheick Hilal.

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Earthen Domes and Habitats Fig. 2: Localisation of analyzed villages

(Figs 1-2). These are habitats mostly built in earth, with anything from a cluster of small hamlets, to villages to compounds of several hundred houses. Though this architecture displays many constants, it is also extremely rich and varied both in its urban organization and in its constructional details. The areas where these villages are located have many things in common that characterize their territories, such as a harsh climate and barren landFig. 5. Panoramic view of Er Raheb. Example of village with unstructured framework

The inhabitants of dome villages In 4,000 years of history, Syrian Bedouin tribes have changed, as has their relationship with the state, but the way of life, economically and socially, has remained the same and can still be seen today. The villagers, after transition from the nomadic to the sedentary, form a cohesive group with a strong community spirit arising from the need to survive in adverse environments. Today, there are approximately 300,000 Bedouin in Syria, of which half are sedentary, most alternating stable periods with seasonal migrating periods towards grazing. This is an alternative solution ethnologists term â&#x20AC;&#x2DC;semi-nomadismâ&#x20AC;&#x2122; (Zecchinelli, 1997). The herd remains an important factor, even in semi-sedentary tribes, and consists mainly of the Awassi breed, a very strong, quite large sheep with undulating wool. The Bedouin can sell milk and milk products to city markets (cheese, butter and yogurt), along with wool and meat (Aurenche, 1984). During the dry season, when pasture around the village is no longer sufficient to feed the herd, part of the population heads for more fertile areas in the east of Syria, where, near the Euphrates, they live during the warmer months in tents, according to the nomadic tradition. Only a small proportion of the herd remains in the village to ensure a supply of milk for the inhabitants. In recent decades, the development of transport such as cars and trucks has changed the way they move about the territory. Indeed, in spring and autumn, when the tribes settle in areas of summer or winter grazing, tents and

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Fig. 3: Communal space in Rasm Hamd

Fig. 4: Communal vegetable garden in Feidane

animals are transported by road. Even the supply of grain, water and basic necessities is done by trucks that supply the villages regularly. The women are largely involved with food and housekeeping. The head of the community is the mukhtar, the representative of power in the village, who occupies a privileged social and economic position, elected by the villagers.

eration of housing seems to be a consequence of the physical and social climate. The architectural form and expression of Syrian villages is not derived from an aesthetic search, but from a deep knowledge – though often subconscious – of the place and its resources. The builder has expressed certain social and cultural needs, and has established a delicate balance between his house and the forces of nature from which he seeks to protect himself. In general, villages in Syria seem to be distinct and characterized by the disorganization of their space, owing to the fact that the agglomeration is not based on any previously thought out plan (Ghiyas, 1984). The urban organization of these villages, in groups of varying density, occurs in two main types of arrangement: ‘free’ or ‘structured’ (Fig. 5-6).

Urban structure morphology of dome villages The principles of transition and self-construction that characterize these ways of living are crucial prerequisites for understanding the process of formation and evolution of human settlements. Buildings in a scattered settlement is a nonexistent phenomenon. Agglom-

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Earthen Domes and Habitats Fig. 7: Jute net weaving in communal area

Fig. 8: Trucks supplying everyday goods

The ‘free’ organization with a more spontaneous and informal appearance, presents housing units dispersed over the territory connected by an irregular and spontaneous road network. This organization is found in the older villages. Inside the village there are no defined paths, but the passageways are determined as a result of residual spaces between housing units. Similarly, there are no designated meeting spaces. A gap between blocks, or an open space can become the place where the community gathers together to carry out common tasks. The ‘structured’ arrangement sees the location of housing units, often in blocks, as the hierarchical organization of both open space and circulation space. However, this type of arrangement also preserves a spontaneous aspect, since it is the result of a spontaneous way of building in which individuals cater to the construction of their own houses. Therefore, the picturesque often wins to the detriment of functionality. Fig. 6: Panoramic view of Feijdane. Example of village with an organized framework

Fig. 9: Mosque built with modern materials in Oum Aamoud Kebir

The settlement consists of groups of separate but adjoining houses. Clusters of domes are variable in number. The cases commonly encountered are a mix of independent domes and of double or triple domes. A number of villages, however, present a large number of five to ten dome groupings. At the heart of these villages, the organization of the dwelling unit is divided into two main types: open or closed. Whatever the type of unit, they are always composed of enclosed buildings with domes and flat roofs and a covered outdoor area with a mastaba, central or attached to one of the facades, along with smaller units for storage and animals. Generally, each household has its own well. The open unit is a straight building or L-shape, in an area which is not visually defined. The unit can be enclosed either directly by the buildings, leaving a passage for access, or by a wall that encloses the unit and creates a courtyard. Although it is possible to combine a number of villages operating under a

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Fig. 10: Road with wastewater channel in Rasm Hamd

Fig. 11: Road defined by contiguous buildings in Oum Aamoud Seghir

similar urban layout, each village has its own peculiarities that distinguish one from another and makes each village unique. Circulation The organization of traffic in the villages depends on service by the main access road. Indeed, some have a main entrance to the village, which is subdivided into a multitude of internal roads, while others are circumscribed by a road that radiates other avenues to the centre. One also frequently encounters the case of roadside villages which have virtually no internal road network, with numerous and direct entries from the main road. Similarly, the presence or absence of pedestrian pathways arises from the manner in which the road network developed within the village and the presence or absence of open spaces within it. The communal areas do not always have identifiers; they are also the result of spontaneous aggregation requirements.

Fig. 12: Road undefined by contiguous buildings in Rasm Hamd

Spaces and public places in dome villages Public spaces can be defined as spontaneous spaces, residues of a settlement phenomenon without rules of urban organization or hierarchical definition of spaces. The daily use and enjoyment of outdoor spaces has gradually led to the formation of common and meeting areas, the form of which shows the irregularity and randomness that is a consequence of the absence of planning. The lack of urban organization is also confirmed by the scarcity of public services. Schools and mosques have been introduced only recently and built with modern materials and there is almost no parallel to these types made with the constructive technique of this study. The mosque is usually located near the centre of the village, but the school lies more frequently in the periphery. These are the only public buildings that are routinely found in villages, except those too small to have their own

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Figs. 13a-f: Comparison of urban morphology of some northern Syrian villages

Earthen Domes and Habitats

schools. Similarly, larger villages possess from one to several shops, while others regularly receive the passage of peddlers. In each village there is a cemetery outside or adjacent to it, or, in the case of larger villages, there may several in different places. Water supply and sanitation in dome villages In these regions, water is always a precious asset. Indeed, years of poor rainfall generate serious problems of supply. Usually the water is pumped directly through public and private wells located in the village. They are often associated with a cistern and generally work with a pump. In some villages, regular water supply is ensured by means of a tanker. Generally, wastewater is simply discharged into the street. At best, a central pit is dug to which each household may ‘connect’ in the form of a small covered gutter, or a passage through the private wall of the dwelling. In the village of Rasm Hamad, the slope has been organised to improve the flow of waste. The wastewater is collected through small canals, 10-15 cm deep, present in current housing units and which connect to the main system. Such collective consciousness concerning the organization of sewage is limited to a few isolated cases. List of References Aurenche, O. 1977, Dictionnaire illustré multilingue de l’architecture du Proche-Orient ancien, Lyon Aurenche, O. 1981, La maison orientale. L’architecture du Proche Orient Ancien des origins au mileu du Quatrième Millénaire, Librairie Orientaliste Paul Geuthner S.A., Paris. Aurenche, O. 1984, Nomades et sédentarie, perspectives ethnoarchéologiques, Editions Recherche sur les Civilisations, Paris Bendakir, M. 2008, Architecture de terre en Syrie, une tradition de onze millénaires, Ed.Craterre, Craterre-ENSAG, Grenoble Daker, N. 1984, ‘Contribution a l’étude de l’evolution de l’habitat bédouin en Syrie’, Aurenche, O., Nomades et sedentaires. Perspectives ethnoarchéologiques, Ed. Recherche sur les Civilisations, Paris. Faegre, T., 1981, Tende: architettura dei nomadi, Dedalo, Bari Ghiyas, A. 1984, L’architecture traditionnelle en Syrie, Etablissements Humains et environnement socio-culturel, UNESCO, Paris Jaubert, R. & Geyer, B. 2006, Les marges arides du croissant fertile, peuplement, exploitation et contrôle des ressources en Syrie du nord, Maison de l’Orient et de la Mediterranée, Lyon Leick G. (1988), A Dictionary of Ancient Near Eastern Architecture, Routledge Muller, E.1965, En Syrie avec les Bedouins. Les tribus du desert, PUF, Paris Savioli, A. 2006, I Beduini della Siria, Available at: http://www.beitshar.com/Bedu2006.pdf Turri, E. 2003, Gli uomini delle tende. Dalla Mongolia alla Mauritania, Bruno Mondatori, Milano Zecchinelli, C. 1997, Il sogno di Lawrence. Dalla conquista di Aqaba al trionfo del cemento. Tra Sinai e Arabia Saudita, com’è cambiata la vita dei nomadi del deserto, nella terra così tanto amata dall’ufficiale inglese, Available at: http://dweb.repubblica.it/dweb/1997/01/07/attualita/ilviaggio/076sog3276.html

a. Er Raheb d. Oum Aamoud Kebir

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b. Rbaiaa e. Feijdane

c. Rasm Hamd f. Cheikh Hilal

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Earthen Domes and Habitats Fig. 14: Example of public well

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Earthen Domes and Habitats Fig. 15: Wastewater channel in Rbaiaa

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The morphology of the house in towns and villages developed from the material expression of uses, customs, beliefs and the culture of a particular people. The populations of peasants and farmers inhabiting the villages of northern Syria retain a certain heritage of nomadic Bedouin culture, which manifests itself through the use of spaces, through local social relations, and also through the warm hospitality that has always been shown to strangers and desert travellers. Syrian dome dwellings are cell constructions marked by the notable presence of domed roofs that stand out characteristically in the desert landscape. This type of vernacular construction incorporating a corbelled dome is common in the Mediterranean area and is usually built in stone. Far less common is to find them gathering to form groups of dwellings or even whole villages. Even considering the existence of other conflicting examples, the most distinguishing feature of these dome dwellings lies in their character and capacity to be grouped together, along with the use of adobe as a construction material. The distribution and use of the spaces of a house corresponds rather to the layout of nomadic camps, and the shape of the dome could be seen as symbolically evoking the tent. The earthen dome house originated and evolved over time, stemming from a willingness to apply and develop the most appropriate solutions to meet human needs in relation to the potential and resources of the environmental context. The geometry of the dome itself is not a product of clear intent, but is rather a product in its form and design of the collective intelligence of communities inhabiting the regions of the Middle East. Architecture in such villages does not exactly result from aesthetic research, but from a deep understanding, though often unconscious, of the resources of a place. The owner-builder thus translates into his house certain social and cultural needs, establishing a balance between his village and the forces of nature from which he is seeking to protect himself, living in and integrating into the ecosystem of a particular area.

University of Florence, Italy

Camilla Mileto & Fernando Vegas Polytechnic University of Valencia, Spain

Fig. 1: Camp in a village of northern Syria

The character of the cell may at first sight justify the isolation and free-standing nature of most corbelled domes existing in the Mediterranean zone. While in other places the construction of corbelled domes usually answers occasional, sporadic or seasonal needs and depends on the availability of stone, in this case the absence of stone, the absence of mortars like gypsum, lime, etc., and the absence of wood, determines the creation of dwellings, hamlets and villages built exclusively in earth. The living unit (dar) The construction model is based on the combination of several cells or blocks, which are arranged around a central courtyard. Built spaces are reduced to a minimum: the daily life of the family, the daily preparation of bread, meals, family reunions and childrenâ&#x20AC;&#x2122;s education and play, is spread out. A similar organization is found in the nomadic camp: the tent is a shelter but family life is conducted outside. Several tents are positioned to form a square, creating a sheltered and enclosed space. Unlike nomadic living units, the houses are embellished with certain features

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The architectural morphology of corbelled dome houses

Letizia Dipasquale

Fig. 4: Schemes of Single-dome, Twin-dome and Multi-dome unit

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Earthen Domes and Habitats Fig. 2: An example of a open aggregated units Fig. 3: An example of a closed aggregated units

that meet the needs of the sedentary lifestyle: bread ovens, rooms for fodder storage, chicken coops, stables and wells. These details, complementary to the main dwelling, contribute to a greater sense of the comfortable, practical and stable homestead. The basic forms of aggregated units, though not easy to categorize, can be distinguished as either ‘closed’ or ‘open’(Figs. 2-3). In the former, a central space is enclosed by buildings and a fence wall with a small entrance passage. This fence wall is generally low, thus allowing a view of the courtyard while still preventing access by animals or outsiders, though only in rare cases is it secured by lock. In the latter case, the organization is rather different: the main unit can be surrounded by other complementary buildings but the limits of the units are not defined. Communal and private spaces in this case are somewhat mixed

up where areas belonging to a particular house may also be used as common thoroughfares. There exist endless variations to and forms of the above two types, resulting from the spontaneous growth of housing through the repetition of the basic form, the main dome, with adjacent buildings, which may take on many different shapes and sizes. Individual domes group together to form dwellings which, in their various forms, depend on certain factors related to the social characteristics of the owner/builder of the house: the state of well-being of the family, the frequency with which the building is used, type of farming adopted (crop-agriculture or pasture), and the number of components in the nucleus (Fig. 4). Single-dome unit This is the simplest type of housing where the interior space is organized to meet to all domestic needs. One part has a floor raised by 20-25 cm and covered with mats or carpets, being the space for living and sleeping with blankets and sheets stored in a corner. Food, drinking water, tools and kitchen utensils are stored in the area nearest the entrance. Here there is no fence to demarcate the area of the property, more often in front of the dome there is a terrace (mastaba), acting as a sort of extension of the interior space. Fig. 6: 360º view of the an introverted court house in Oum Aamoud Kebir

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4 1

1. Dwelling-house 2. Stable 3.Animal fence 4. Terrace ( mastaba) 5. Oven

3 1

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Fig. 5: Housing unit evolution scheme. Re-elaboration from Nomades et sedentaires. Perspectives ethnoarchĂŠologiques, Aurence, 1984

3 1

3 2

3 5 2

Twin-dome unit The single cell is most often paired with another to form the household unit. The nucleus can occur in isolation or surrounded by a perimeter fence. Even in cases where there are no perimeter walls or explicit limits surrounding a courtyard, there are always implicit signs (changes in surface or ground level) in order to announce the progressively private domain of the dwelling place. Multi-dome unit In the more evolved type of living unit, sets of domes are arranged in line on one or more sides of a quadrilateral. A perimeter wall of earth and stone (sur) can enclose the square, leaving some room for the entrance passage. The complex is managed from the main unit of housing, which can be formed by a single-dome building or two inter-connected blocks. Around this other cells are added over time, each with its own specific role.

With the exception of the small storehouses that appear occasionally in family courtyards and sites, cell domes adopt fixed dimensions for the whole of the village without reflecting any particular hierarchy of use. That is to say, from the exterior, except for other parallel signs (relative position, lime washings, decorations and furniture), a dome used as a dwelling is not distinguishable from one used as a granary or stable. The same architectural typology is, therefore, valid both for the inhabitable and auxiliary spaces. The principle housing cell functionally and spatially organizes the whole of the complex, linking the different functionally complementary service elements. An implicit hierarchy exists in the relative position of the dwelling area with respect to the storage area. Moreover, the dwelling area usually has a raised terrace (mastaba) at the main entrance of the house. In an extended family, the householder and his wife occupy the larger and most important cell, while the married sons and their families inhabit other lesser domes.

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Fig. 8: Organization of spaces in a housing in Oum Aamoud Seghir

Earthen Domes and Habitats Fig. 7: Organization of spaces in a housing in Joub Maadi C. Court, ‘Haush Sahn’ D. Dwelling-house O. Oven

The distinction of function for each unit naturally leads people to live largely outside, where most of the daily life takes place. The outdoor area has a distributive function, whilst being at the same time a common space for many important activities (Fig. 6). This type of dwelling in multiple structures allows the addition of new blocks, in cases where extra space for production is necessary or to make room for new members of the family (Fig. 5). A tent is sometimes set up next to the living unit. Its location may be temporary, related to the period preceding the final occupation of the house on the return of the family from transhumance. In other cases, the presence of a permanent tent near the dwelling may be used for the housing of livestock, for the storage of straw and firewood, or for the preparation of milk products, such as laban (yogurt), djebneh khadra (white cheese) and samneh (oriental butter, a speciality of the region). Organization of space in a housing complex Dwelling-house, ‘Gurpha’ The main space of the house is called a Gurpha, being the space for housing the family and the reception of guests. It may consist of a single cell, but more often comprises of two domes communicating by an arch (Qaus or Qantara), equal in size to the dividing wall, that may be separated by a curtain. Usually, there exist no partition walls in the space under the domes. In poorer households animals are also housed in the main room during cold winter nights.

C. Court, ‘Haush Sahn’ D. Dwelling-house E. Hen-house F. Animal fence H. Stables, ‘Hazera’ or ‘Qabu’ S. Stores T. Terrace, ‘Mastaba’

Orientation is frequently north south, with the main opening towards the south in order to take full advantage of solar irradiation, and to protect the house from the easterly and north-easterly winds which are very common to this area of Syria. This space, as with the inside of a tent, has a multifunctional character: by day it serves as an area of residence and shelter from the harsh climate, by night as a sleeping room with mattresses spread around the floor. Passing through the entrance of the cell we find a small area (attabeh) on a level a few centimetres lower (10-20 cm) than the main floor. This space, being the width of the front door and roughly square in shape, is used for storing shoes that are not worn inside the home. Here a container (Khabia) containing water for domestic use is often placed, which is sometimes used for washing. A small hole made in the threshold of the door allows the water to pass from inside the dome to the external drain. The interior has no fixed furniture. Blankets and in some cases thin mattresses are placed in a pile in a corner of the room (frash), and only at night are arranged on the floor for sleeping. Objects are placed in niches (khezana gedaria), built into the thickness of the masonry. The shapes and dimensions of the niches are variable: there are

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Fig. 9: Organization of interior spaces in the dwelling-house, â&#x20AC;&#x2DC;Gurphaâ&#x20AC;&#x2122;

some very small cavities, arranged in sequence, some the size of a window, or niches that rise from the floor to the height of 1-1.50 m. In most homes the niches can be closed by wooden doors to create a wardrobe. The depth, two-thirds the thickness of the masonry, is constant. The main walls in housing can be decorated by relief (raff), always made in raw earth, with floral or geometric patterns, and can form small shelves. Access The closed arrangement of this type of architecture responds to climatic, constructional and social factors. Domes usually only have one access for each unit or even one access every two units when inter-connected. The door of a dome dwelling frequently represents the only entrance for the inhabitants and sometimes the only illumination and ventilation point for the internal space. The only wood used in the construction may usually be found around this door, i.e. the lintel and the door itself. Openings In addition to the gateway, openings are small and rare. Consisting of small square, rectangular and round (taqa) holes, they are usually oriented towards the east or west, to capture summer breezes, and allow for night ventilation and the entrance of moderate sunlight. Windows are often found in the most recent housing (nafeza or shubbak), usually on the main elevation.

Fig. 10: Organization of interior spaces in a oven

Fig. 11: Traditional kitchen with niches Fig. 12: Frash, place in the dome where mattresses are placed

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Earthen Domes and Habitats Fig. 13: Open unit with terrace (mastaba)

Fig. 14: Internal court in a unit of Twall Dabaghein

Bathroom, ‘Marhad’ or ‘Baet Al-mai’ Traditional houses are not always equipped with bathrooms, and when present they tend to consist of a hole in the ground inside a special compartment (dome or flat roof) or in the livestock area, in this case protected by a C-shaped wall, varying in height from 1 to 1.5 m. In wealthier homes a bath (hammam) can be found along with clay containers for pouring water. Kitchen The Syrian house has various spaces for the preparation, storage and consumption of food. The tableware and supplies are placed in a specialized unit (matbakh), where today, in addition to traditional earthen shelves, wooden shelves and in rare cases a refrigerator can be seen. Another storage space, used to preserve foodstuffs and fruit for winter, may be located in a separate room (baet al- muna or al-fejjeh) or else in a part of the main room separated by a wall of the cell where food stocks are placed in small holes (kuara). Traditionally, meals are prepared outside according to the nomadic custom. However, today many families use gas stoves and prefer to cook indoors. Firewood is stored in the same place as the dishes, or in a separate compartment (mustauda ‘hatab). In each unit there is an oven (mauqed, dfeeh or kanun) for the daily preparation of bread. The traditional oven is a simple circular base in clay, about 60 cm high, with a cavity in the centre for the burning of straw and small

branches. The cavity is covered by a convex metal disc, on which a layer of dough of variable thickness is placed. The oven can be outside, consisting in this case of a cylindrical base made of stone and earth, with an upper cavity shape where the dough is cooked and below a space for burning wood. Meals are generally consumed in the main house. Courtyard, ‘Haush Sahn’ This is the courtyard around which the various functional cells for housing are arranged, surrounded by an earthen fence wall (sur) or by the constructions of the dwelling. It is a highly frequented space where one can find small fenced off areas or shelters for animals, small domes used as chicken coops (qunn) and in some cases a fireplace for the preparation of meals. At the centre of the courtyard or in an area adjacent to the house there is often a well (be’er) supplying the family with drinking water. The well can be simply a hole in the ground covered by a flat stone, or it may have an above-ground base built from stone or from mud and stone, dug by hand, from which water is almost always hand drawn by a system of pulleys. In most villages with an abundance of water, short-stemmed plants are grown in a small orchard-garden (hakura) in the courtyard. In the past it was commonplace for the inhabitants to sleep outside in the courtyard on summer nights on beds consisting of an earthen base supported on a mattress of canvas sacks filled with straw.

Figs. 15a-i: Examples of gruping of domes in surveyed units. 273

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a. Twin-dome unit in Er Raheb

b. Multi-dome closed unit in Oum Aamoud Kebir

c. Multi-dome open unit in Joub Maadi

d. Multi-dome closed unit in Tayara g. Multi-dome closed unit in Rbaiaa

e. Multi-dome closed in Rasm Al Bugher h. Multi-dome closed unit in Rasm Hamd

f. Multi-dome closed unit in Feijdane i. Multi-dome closed unit in Aamoud Seghir

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Earthen Domes and Habitats Figs. 16a-d: Main types of domes in the Syrian vernacular landscape: Simple dome, Sultan dome, Transition dome, Flat-roof dome

Terrace, ‘Mastaba’ The terrace is made of stones and earthen mortar, covered with a layer of earth and straw. It is sheltered from the wind and used for drying fruit and vegetables. On hot summer nights it becomes a sleeping place, when the outside temperature is cooler than the house as it releases the heat collected during the day. Stables, ‘Hazera’ or ‘Qabu’ In the Bedouin culture livestock has always been a valuable asset, though cattle were more numerous in the past than today. A space was designated for cattle away from the main habitation, in a tent or inside a perimeter wall with a woollen cover. Over the years, with the reduction of herds, animal enclosures have moved into the courtyard of the house. The facilities are very rudimentary, consisting of a simple wall in stone and earth to prevent the sheep escaping. In some cases a specific building, a flat roof or dome, is reserved for the shelter of the livestock. Chickens and hens shelter in small cob domes located in the courtyard, and during the day they are allowed to roam free around the territory of the house. Stores Rooms used for storage of objects are numerous and varied, under domes of the same type used for housing, or smaller cob domes (qubbia). Sometimes even flat-roof buildings are used for this purpose. The domes, which are used to store straw (matban), possess a hole (af’a) at the top of the cover. The aperture allows easy access to the straw compartment, and is closed with earthen mortar when the space is filled. The openings in these environments are generally oriented towards west, essential for the ventilation of the enclosure and to reduce infestation by insects.

model, i.e. the dome raised by overhanging bricks, is found in a wide variety of types and variations. It is to be noted that the typology of construction adopted is closely linked to the available resources and materials of the site, and the original model is adapted to cater for specific housing needs. From the variety of domes observed, we can identify certain recurring types, which differ from one another in formal aspects and constructional character (Fig. 16a-d). In the description of each type the formal-aesthetic characters and their relation to constructional aspects are highlighted. Despite the dome’s imposing character on the shape of the building, independent of the architectural variants to be shown in this text, the layout of the cell unit is always square, which aids in grouping units together. The measurements may vary from one village to another, but uniform inside the Fig. 17: Map of distribution of types of domes in northen Syria area

Alep

Flat Roof Dome Sultan Dome Transition Dome

A classification of corbelled dome houses The repertoire of dome structures, while based on a single constructional Simple Dome Hama

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Such factors are, for example, the availability of branches to truncate the domeâ&#x20AC;&#x2122;s peak with a flat roof; the availability of materials and the degree of exposure to rainwater splash of the facade, surface run-off water, human and animal damage or knocks, etc., which settle the height of the perimeter base or wall. Variants The different height of the perimeter wall may help to distinguish more clearly the two type of domes in the vernacular landscape of the domed villages of Syria: the so-called dome of the Sultanya or Sultan dome, with a perimeter base that rises up to the height of the lintel of the door to become a real wall of the facade, and the simple dome with a very low base. Between the two, there are other variants according to the height of the perimeter base. In the interior, this difference is shown in the respective dimension and height of the pendentives that allow the transition between the square-shaped layout and the circular dome. The material and constructive differences are minimal, since they are all built with adobe walls and corbelled domes. The profiles of the domes allow us another classification, that would divide them into complete pointed domes and truncated domes, where the availability of wooden branches cuts short the construction of the dome into a flat roof. Normally, these truncated domes have a medium-high perimeter base, approximately two-thirds the height of the entrance.

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Earthen Domes and Habitats Fig. 18: Simple domes in Sourj Fig. 19: Simple dome in Meksar Shamlei

same urban landscape, at least for the dwellingâ&#x20AC;&#x2122;s main spaces. Occasionally, there exist some circular modules of reduced dimensions for storage purposes covered by smaller domes. Other factors determine the section profile of the domes, usually common to all buildings of the same village, though this can vary from place to place.

Simple dome Description The dome rests on a stone perimeter base that rises a few centimetres from the ground. Distribution area Central Syria, Hama region. Villages where identified Cheikh Hilal; Maksa Shamlei; Sourj; Twall Dabaghein. Geometric and dimensional features The building has an ogival profile; the dome reaches almost to the ground without interruption. The base is square. The shell of the dome is entirely visible from the intrados or the extrados. The size of the plans of Sultan domes observed varies from 3.0-3.5 m by 3.0-3.5 m. The height is variable from 4.0 to 6.0 m. Constructional features Base: the dome is built on a stone perimeter base of between 30 and 60 cm in height.

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Fig. 20: Elevation, plan and section of the simple dome Fig. 21: Axonometric view of a simple dome Fig. 22: Simple domes in the abandoned village of Meksar Shamlei

Connecting arches: the height at the keystone of internal linking arches is limited. The presence of the arch is ascertainable from the outside of the building, from where the extrados of the arch may be perceived. Variants Variations to this type basically depend upon the height of the stone perimeter base and the type of stone used, which can lead to diversification from a formal point of view. Comments This is the original stock type, which most evokes the idea of the tent. Its diffusion is probably dependent on the difficulty of finding stones in the region to construct the base.

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Earthen Domes and Habitats Fig. 23: Sultan dome in the village Rbaiaa Fig. 24: Sultan dome in the village of Feijdane

Coupling between the base and the dome: the dome in earthen bricks rests on the stone perimeter base. The base of the pendentive is built in stone and at a height of between 30 and 60 cm. Texture walls of the dome: the dome is made of bricks arranged head to head, which begin to corbel from the 4th-5th course. Aperture: the only opening is the front door, which allows the passage of light and air. Sometimes there are ventilation holes at the bottom of the dome. The door is positioned at the centre of the dome when the cell stands alone, and to one side at an angle in the case of two connected domes. The frames are made of adobe masonry, and in some cases stone. The lintels of the doors can be made of stone or wood.

Sultan dome Description The building consists of a walled box, under a domed cover with an ogivalparaboloid profile. Distribution area Northern Syria, Aleppo region. Villages where identified Er Raheb; Feijdane; Mazraat al Rouihieb; Oum Aamoud Kebir; Oum Aamoud Seghir; Rasm Hamd; Samad; Rbaiaa. Geometric and dimensional features The construction is composed of a square walled box, surmounted by a dome cover. From the exterior, the two elements of the box walls and the dome are clearly identifiable, however, from inside the transition from rectangular box to cover occurs seamlessly. The box has a square base on a plan varying in size from 3-4.50 m reaching a height of between 4 and 6 m. Constructional details Base: the wall is supported by a stone perimeter base of height between 30 and 80 cm. The availability of stone at the location influences the height of the base. Walled box: made of adobe, generally with three heads thickness. The height may vary from 1.8 to 3 m, in all cases exceeding the height of the entrance door. While on the outside the wall has a rectilinear geometry, the internal wall begins to curve inwards from the level of the dome. Coupling between the ring and the dome: the base of the pendentive can be made in brick, wood or stone at a height of between 1 m and 1.50 m. Very often this coincides with the height of the stone perimeter base. In cases

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Fig. 25: Elevation, plan and section of the Sultan dome Fig. 26: Axonometric view of a Sultan dome Fig. 27: View of a row of Sultan domes in Feijdane

Variants The profile of the base wall may be straight or shaped. A shaped profile allows the disposal of rainwater from the dome, conveyed down gutters in the concave point of the profile. A straight profile was found in the most recent examples. The height of the stone perimeter base is variable, depending on the amount of stone available on site. Comments This the most widespread type in the region to the southeast of Aleppo. It can be seen as a simple evolution of the dome, since the presence of a high wall allows for greater use of the interiors. The dome in this case is contained and protected in the lower part by the base wall that serves as structural support.

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Earthen Domes and Habitats Fig. 28: Transition domes in Rbaiaa Fig. 29: Transition domes in Nawara

where the pendentive is made of brick, the progressive overhanging of the brick courses is less pronounced. Texture walls of the dome: starting from the base of the pendentive, the interior of the base wall starts to progress from the square to the circle. When on a circular plan, the bricks are arranged in spirals, initiating the revolutions of the dome. Openings: windows are sometimes present in addition to the entrance door, supported by a lintel and jambs of wood or stone, depending on the area. Square holes for ventilation of the interior space are often located at the base of the dome. The lintels of the doors are made of wood and brick or stone. Connecting arches: the internal connecting arch is of a considerable height (h = span 1.50-3.50 m) and, in more recent examples, is sometimes replaced by a wooden lintel.

Domes set on low stone perimeter base, or transition dome Description The dome is supported by a stone perimeter base. Distribution area Region to the south of Aleppo. Villages where identified Rbaiaa; Er Raheb; Tayara; Nawara. Geometric and dimensional features The stone perimeter base of the building is of variable height, following the outline of the door and architrave, and upon this rests the adobe dome. From a formal point of view, this type is related to the real dome, while the construction and structural design is that of the Sultan dome. The roof dome is not enclosed by a wall, but its shell is visible from both the intrados and extrados. Sizes of plan and height are restricted from 2.50-4 m. Constructional features Base: base wall in stone, height between 50 and 120 cm. The profile of the foundation follows the outline of the door. The stone perimeter base, in some cases, consists of two different materials: the stone exterior and adobe interior. Coupling between the ring and the dome: the base of the pendentive is usually made of stone. The height of the pendentive corresponds to the height of the top of the stone perimeter base and varies between 50 and 120 cm. Texture walls of the dome: as with the Sultan dome, this dome is made of

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Fig. 30: Elevation, plan and section of the transition dome Fig. 31: Axonometric view of a transition dome Fig. 32: View of transition domes in Rbaiaa

Comments This type is generally found in areas where there is a greater abundance of stone.

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Earthen Domes and Habitats Figs. 33-34: Flat-roof domes in Joub Maadi

bricks arranged head to head, starting to overhang from the 4th to 5th course. Openings: the lintels of the openings can be made with stone or wood. In some cases reused elements can be observed (stones of Byzantine origin) in jambs and architraves. Connecting arches: the height at the keystone of the internal connecting arch is limited to between 1.30 and 2.00 m. Variants The perimeter base is generally made of stone, basalt or limestone depending on the region, but sometimes the base wall can be found in adobe.

Flat-roof domes Description The dome is not completed, rather the top is closed by a wooden structure covered with earth. Distribution area Region west of the Euphrates River. Villages where identified Joub Maadi, Rasm Al Bugher. Geometric and dimensional features The structure consists of a truncated cone closed by a flat wooden cover. Constructional features Base: stone base and adobe wall, of a height between 50 and 180 cm. Profile of the base follows the profile of the door. Coupling between the ring and the dome: the base of the pendentive is usually made of stone, with some in brick. Starting height of the pendentive is variable. Wall texture: as in the Sultan example, the dome is made of bricks arranged head to head, beginning to overhang from the 4th-5th course. Openings: architraves openings in stone or wood Connecting arches: internal connecting arches are variable in height depending on the base wall and the height of the dome. Variants The base wall may be low (as in the simple dome) or exceed the height of the door (as in the Sultan dome). Comments This type of construction has been observed in rare cases in the region south of Aleppo. This is a solution adopted in cases where parabolic or ogival domes have collapsed. In recent years it has been deemed preferable to repair domes with flat covers rather than carry out expensive, labour-intensive rebuilds. In the region east of the Euphrates River, this type is common, the main motive favouring the use of this technique lies in the presence of large quantities of wood in the area. It seems that the technique was imported from the region of Al-Jazirah (Alyundi, 1984) to the north of the country, in order to reduce the horizontal space to be covered, and to reduce the quality and

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Fig. 35: Elevation, plan and section of the flat-roof dome Fig. 36: Axonometric view of the flat-roof dome Fig. 37: View of a row of flat-roof domes in Joub Maadi

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Fig. 38: Elevation, plan and section of smaller domes in cob Fig. 39: Axonometric view of a smaller dome in cob

Smaller domes in cob Description Small domes in earth shaped by hand and stone. Distribution area Aleppo and Hama regions. Villages where identified Rbaiaa; Cheikh Hilal; Mazraat al Rouihieb; Maksa Shamlei; Er Raheb; Oum Aamoud Kebir, Oum Aamoud Seghir; Rasm Hamd, Samad; Sourj; Tayara; Nawara; Twall Dabaghein. Geometric and dimensional features The plan is generally circular and the profile ogival. Height can vary from 0.50 to 2.0 m. Constructional features Base: when present, a small perimeter base is made of stone, never exceeding a height of 50 cm. Wall texture: the structure is made of earth and straw, kneaded and applied by hand. Openings: openings are rare in this type. Variants The structure of the dome can sometimes be achieved with rows of stone and an abundance of earth mortar. Comments This type of dome has only service uses (stock, silos and animal shelters). Bioclimatic aspects The Syrian dome, besides offering a means of habitation that is practical in areas of scarce natural resources, is able to meet the demands of hygrothermal welfare in a semi-arid climate due to cooling abilities achieved by the use of certain materials and the form of the construction. Earthen material has a naturally elevated thermal inertia, resulting in damping and a lag of changes in internal temperature compared to those of the outside. The earthen walls also regulate the humidity of the environment through vapour permeability, contributing further to the conditions of hygrothermal and respiratory comfort A dome has half its surface irradiated by the sun and the shape of an ogival dome determines that a position of incidence of solar irradiation is very

low in the hottest hours of the day, so reducing the heating effects of the sun. The surface area of a dome is greater than that of a flat surface, so when exposed to strong sunlight the curved surface temperature is reduced compared to that of a flat cover. For the same reason, its capacity for heat dispersion at night is greater. The volume covered by a dome, being greater than that of a corresponding flat coverage, allows cooler air to collect at the top, consequently cooling the layers below. Compared to a flat cover, the dome alters the section of the air flow as it rises, therefore increasing speed. This increases the cooling capacity and creates a draw of air, where openings are present, allowing the extraction of natural hot air from inside the rooms. During the day the upper layers of air, further away from the soil, are generally cooler. For this reason there is a cooling of the exterior surface of the building at the dome, which does not occur in the flat coverage. Since the dome is exposed to the most intense rays of the sun, there is always one shaded part and one in the sun, so producing a temperature difference between the two parts and a corresponding movement of air on the inside. The openings are designed to maintain the internal microclimate: the low ventilation holes allow constant natural ventilation and an exchange of air during the night. The dome shape permits the run off of rainwater and snow, frequent in this region, thus diminishing the risks of degradation in comparison to a flat cover. List of References Aurenche, O. 1977, Dictionnaire illustré multilingue de l’architecture du Proche-Orient ancien, Lyon Aurenche, O. 1981, La maison orientale. L’architecture du Proche Orient Ancien des origins au mileu du Quatrième Millénaire, Librairie Orientaliste Paul Geuthner S.A., Paris. Aurenche, O. 1984, Nomades et sedentaires. Perspectives ethnoarchéologiques, Ed. Recherche sur les Civilisations, Paris. Bendakir, M. 2008, Architecture de terre en Syrie, une tradition de onze millénaires, Ed.Craterre, Craterre-ENSAG, Grenoble Besenval, R. 1984, Technologie de la vôute dans l’Orient ancienne, Synthèse n. 15, Ed. Recherche sur les civilisations, Paris. Daker, Naoras Contribution a l’étude de l’evolution de l’habitat bédouin en Syrie, in Leick G. 1988, A Dictionary of Ancient Near Eastern Architecture, Routledge, Ghiyas, A. 1984, L’architecture traditionnelle en Syrie, Etablissements Humains et environnement socio-culturel, UNESCO. Meda-Corpus 2004, Traditional Mediterranean Architecture, École d’Avignon, Avignon. Tunca, Ö., Meunier, J-M, Lamisse, J-Cl & Stockeyr, E. 1992, Architecture de terre. Architecturemere. Portrait de deux villages en Syrie du Nord, Musees royaux d’art et histoire, Bruxelles

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quantity of wood used for the cover structure, thus avoiding rebuilding the very fragile upper part of the dome.

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The experience of semi-nomadic communities in Syria is the experience of mobility and flexibility, entrusted to the tente–maison–cour. It is the game of annual sedentarisation which leads people initially to live in tents, then set them up close to their traditional homes (abandoned for most of the year) and then lastly to leave the tents and occupy the traditional home only, before setting out on a new journey; with the yard acting as storage space for various materials, food, fuel, construction materials, etc. All within the space of about two weeks, while the presence is restricted to a short period of time, 2-3 months, due as it is to reasons linked with raising livestock. The tente–maison passage forms a progressive movement away from the traditional Bedouin model, which sees the tent as the residential element of reference. Despite the variety of plan arrangements, their houses consist of 2-3 main rooms plus accessory rooms. The spaces undergo gradually transformation from the initial moment of partial settlement to the abandon of the tent (Jarno 1984). From an initial moment in which the rooms are dedicated to the arrangement of mattresses to sleep, frash, the receiving of guests and the storage of victuals, they move on to a second moment, in which the women’s room can be identified, containing everything required for cooking and manual work, then the men’s room and the children’s one, also used to receive guests, as well as the one dedicated to the storage of foodstuffs. We witness a clear and progressive specialisation of spaces, which abandon the multifunctional nature characteristic of tents to become more defined, while maintaining a high level of flexibility. Everything has to be easy to move, depending on the moments of the day and relative needs. The central furnishing element is definitely represented by the aforementioned frash, a traditional system of the Bedouin tent which enables the

University of Florence, Italy

arrangement of everything needed for sleeping during the day. The frash usually consists of two parts, a wooden structure (often crosspieces fastened to the saddles of the camels) which makes it possible to raise mattresses and blankets up from the dust on the ground, and a patchwork cover. Usually, each family has just one frash which is transported from the tent to the house and vice-versa and is normally kept in the women’s room. Nowadays the traditional structure is often replaced by less rigid solution, sometimes using whatever comes to hand. During the time spent in the house, the frash is slowly replaced by niches in the walls. These walls are often numerous and bear witness to the progressive appropriation of the house, sometimes featuring raised or coloured decorations. In the passage from the tente to the maison these niches are not initially occupied by objects but used in general, with precise use being made only when the tent ceases to be important. The interior walls are decorated, not only by niches, but also by different sized vents, in square, rectangular and sometimes circular shapes which, in winter, for climatic reasons, are blocked with fabrics, but often host smaller objects, even colourful frills (usually light blue) and sometimes geometric patterns or floral motifs carved or painted and partitions in other colours. Flexibility and mobility have inevitable repercussions on objects and furnishings.

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Corbelled domes interiors: mobility and flexibility

Giuseppe Lotti

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These include rugs on the ground, roll cushions, shelves in the kitchen, made of wood, iron or recycled materials, mirrors, decorated plates, framed family photos, fabric hung on the walls, imitation flowers made of plastic and paper and, increasingly often, the occasional piece of furniture (wardrobes and drawers) which can be defined as ‘sedentary’, bought in town, representing a further element of abandon of the traditional Bedouin lifestyle. Lastly, there is a strong contrast between traditional elements and new technological elements, the expression of a wilfully exhibited and experienced ‘modernity’, from the television, to the stereo system and freestanding or ceiling fans. All the furnishing elements are placed against the walls to free the room for the various activities that take place during the day. The end result is an interior space in which single objects and, even more so, decorations, are enhanced in their individual form to create the family’s interior panorama. In the words of Roland Jarno, we are witnessing ‘un apprentissage de l’espace bati’ which ‘passe par la prise de conscience d’une espace flexible qui remplace un espace mobile’ (Jarno 1984, p. 200). The binomial tente–maison is made up of just a few functional and symbolic objects which interpret the traditional need for flexibility of the nomadic life and, at the same time, the passage towards increasingly sedentary lifestyles, closer to our way of intending space. A trace for those who, seized by the temptation of something new, forget to look to history as the heritage of experience and to others as bearers of knowledge. The case of the semi-nomadic communities in Syria, however, has much to teach us. List of References Jarno, R. 1984, ‘Tente et maison: le jeu annuel de la sédentarisation à Qdeir (Syrie)’, Aurenche O. (ed.), Nomade et sédentaires: perspectives ethnoarchéologiques, Editions Recherche sur les civilisations, Paris. Aurenche, O. (ed.) 1984, Nomade et sédentaires: perspectives ethnoarchéologiques, Editions Recherche sur les civilisations, Paris.

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University of Florence, Italy

Konstantinos Tokmakidis

Hellenic Society, Aristotle University of Thessaloniki, Greece Figs. 1-2-3: Topographical survey

The surveying of corbelled dome villages in northern Syria has to take into account the problems and aims of a measured survey campaign of such a vernacular architectural heritage as the mud architecture of Syrian villages. The investigation of locally observed examples has lead us to several modes of analysis and hypothesis in categorizing architectural, constructional, structural and mineralogical dimensions. The process of categorization can be simplified by and at the same time allows for the identification of types or sets of common characteristics of distinct objects. A deeper analysis can offer a range of solutions so vast and ambiguous as to render their classification as one or the other far from easy.1 The scientific investigation of the specific connotations of single objects implies the elaboration of an ‘ideal model’, obtained by purifying single examples, concretely investigable, of ‘secondary attributes’ that qualify them as ‘individual’ and that depend on factors such as the availability of resources, of specific use/needs, methods of construction, the ability of the builder, etc. The terms type and model, require some clarification, essential for the considerations that we intend to develop regarding the problems and aims of a measured survey campaign researching the mud architecture of Syrian villages. The two criteria around which the discussion on the typological classification of buildings has centred since the 18th century, are function and morphology. Quatremere de Quincy, the first to complete an accurate critical analysis on this theme, introduces a decisive distinction between type and model: “The word type presents less the image of a thing to copy or imitate completely, than the idea of an element which must itself serve as a rule for the model. (…) everything is precise and given in the model, everything is more or less vague in the type”. A few decades later Gottfried Semper (1803-1879), speaking of prototypical forms, asserted: “just as nature in her infinite variety is yet simple and sparse in basic ideas (…) technical arts are also based on certain prototypical forms, conditioned by a primordial idea, which always reappear and yet allow infinite variations…”, so expunging any idealistic value in the term to assign it a ‘positive’ significance, founded on an analogy with natural sciences. The works produced by the artistic industry are in fact “like works of nature, linked together by a few fundamental ideas which have their simplest expression in types”. The classification system proposed by Semper, that should have made clear ‘the derivation of objects and forms from their primordial motivations and from changes in style conditioned by circumstance’, has the merit of conferring practical applicability to the notion of type preserving the significance of ‘generic idea’, without making it resemble a model. Within this context, if type defines a scheme susceptible to being developed in an infinite amount of ways and not a model to slavishly imitate, every artefact which derives from it represents a case in itself, and as such must be investigated. To survey these artefacts, therefore, means recording all their characteristics, postponing to a second phase, through opportune extrapolation and comparative verification, their classification in a determined “typology”. This last process is all but linear, since it implies a dual path both inductive and deductive and which is confronted, even omitting the difficulty of arranging a mass of reliable and adequately representative empirical data, with the paradox according to which to recognize something one must already have recognized it. 1

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Surveying and documenting corbelled dome architectures

Grazia Tucci Valentina Bonora Alessia Nobile

In the vernacular design process, as described by Amos Rapoport, there seems to emerge a coincidental tendency between building model and type, since this has already inherent in itself a very clearly formed idea: “the model is the result of the collaboration of many people over many generations, as well as being the result of the collaboration between makers and users of buildings and other artefacts, which is what is meant by the term ‘traditional’. Inasmuch as the awareness of the model is shared by all there is no need for designs or architects. A house is imagined similar to other wellmade houses in the given area. The construction is simple, clear and easy to comprehend and because of that everyone knows the rules, the craftsman is only called because he has a more detailed knowledge of these rules” (Rapoport 1969, p. 4). The construction of the specific form of a single house takes place by adaptation; it is permeated with the characteristics of immutability, constancy and permanence because it is compared with a model in which changes are so gradual as to form over centuries, hence imperceptibly. At the origin of a traditional artefact there is a model, silently shared by the community of users and makers for whom and by whom it is made, susceptible however to multiple variations, and transcending the specific connotations of a single product. In the case of vernacular architecture, we find ourselves in front of an intermediary situation between handcrafted objects, in themselves unique, and serial production. So the reference to types and technical procedures ‘codified’ by local tradition guides the user-maker to build dwellings that adhere to an identical paradigm, but that simultaneously differ between themselves in some ‘secondary’ characteristics.2 If on the one hand the removal of these ‘secondary connotations’ consents, (by exposing their ‘common denominator’), the elaboration of an interpretative model valid for differing cases and referable to an identical design and constructive ratio, on the other hand, risks reducing them to mere abstraction. It has been proposed to define the survey of historical buildings as an operation that would consent to the reconstruction of the project (Migliari 2004, p. 63). This assertion presupposes conditions that are not only unfound in

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The physicist Alfred Kastler (1902-1984) observed that, to the scale of our senses, we are accustomed to recognise two fundamental properties in what we call objects: the permanence and the individuality. While the first regards directly their durability (the persistence in time of consistency and ‘functionality’ of usable objects), the dialectic that is established between the two terms evidences the relationship between the common characteristics of distinct objects (that constitutes their typomorphological identity) and that which instead identifies them singularly, so differentiating them one from the other.

Figs. 4-5-6: Snapshot of the range map. Examples of some technological details: ventilation openings, niches, pattern of brickwork.

the majority of buildings realized from a ‘project’ (to which they almost never correspond, in that they are often the fruit of numerous alterations over the course of realization), and whose present physiognomy is derived from the incessant transformation, over time, of the ‘original’, but are completely lacking in ‘spontaneous’ architecture. Therefore, the survey operation has since been set up and managed with the precise intention of providing the most complete and faithful documentation possible of this architectural heritage, having in mind that it will be continually updated and integrated. Consequently detailed documentation, consequently, also responds to the needs of controlling the evolution of the processes of alteration and degradation facilitated by the disappearance of the knowledge and techniques of traditional maintenance and by the diffusion of inappropriate interventions made with criteria and materials incompatible with the physiology and character of these architectures.

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An integrated surveying method Topographical surveying Topographical surveying is used to define the three-dimensional position of points in space. The position of each point measured is expressed as a triplet of Cartesian co-ordinates (X, Y, Z or N, E, Q) in relation to an existing reference system or one specifically defined (cartographic reference system or local reference system). The tools used for field surveying are many and various. In this context we considered: - A Global Positioning System (GPS) receivers and antennas, - A Total Station. A GPS uses signals from a constellation of satellites orbiting the earth to locate points. The reference frame that enables the location of each point to be fixed, is an absolute system adopted worldwide. The geocentric coordinate system has its origin at the centre of the earth mass. The X axis passes through the Greenwich meridian on the plane of the equator, the Z axis runs north-south with the northern portion being positive and the Y axis also lies in the mean equatorial plane thereby creating a right-handed Cartesian coordinate system. It is therefore possible to geo-reference a point (i.e. define its position in relation to the Earth) or, in our case, a village or a single dwelling unit thereby overcoming the problems arising from the non-availability of adequate maps and from the difficulty in recognizing the villages retrospectively.

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Figs. 7-8-9. Snapshot of the points cloud. Examples of non-removable objects inside the dwelling units surveyed by laser scanner technology. Example, Joub Maadi.

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A Total Station combines an automated angle-measuring component with an electronic distance-measuring component to measure a pair of angles and a distance relative to the vertex where the instrument is placed. These measurements determine the position of the observed point relative to the starting vertex. The choice of equipment and surveying techniques depends on the degree of accuracy required from the survey. The on-site survey in the selected villages was divided into the following sequential phases: - The topographic frame of reference, - Measuring targets (required for photogrammetry and/or laser scanning), - Detailed surveying. The topographic reference frame The topographic reference frame is composed of a series of consecutive lines whose ends were marked in the field, and whose lengths and directions were determined from measurements. Closed traverse or additional redundant measurements (network) were generally preferred in order to check the results of the survey and to enable the most rigorous adjustment procedures to be applied. All the traverse stations were materialized and then carefully sketched and referenced by measuring their distance from a nearby fixed object to ensure their future identification.

Station locations were selected in such a way as to ensure complete coverage of the area to be surveyed: in the simpler cases a closed traverse was defined around each dwelling, in the more complex villages, straddles of one or maximum two lines were branched off to ensure that all internal and external spaces were included. Measuring targets Artificial points (targets) which three-dimensional coordinates are known were defined in relation to the traverse station. These targets were set up during the survey for two reasons: they were used firstly as control points for aligning the laser scanner 3D range maps and secondly as control points in a photogrammetric orientation as described below. The targets were then removed, taking care not to damage the protective layer of plaster on the walls. Detailed surveying A total station topographic survey was carried out in the Rbaiaa and Rasm al Bugher villages using celerimetric measurements: the process was quite fast because no redundant measurements were taken. The celerimetric measurements were used to ascertain the size and the shape of the units being analysed: this information was obtained by considering the surveyed objects as composed of a series of connected straight lines, with each line being determined by two points. When total station is used the point to be determined has to be collimated prior to the topographic measurement (collimation is the accurate identification of a point using the telescope attached to the instrument). Each point has to be highlighted simultaneously on a sketch or on a photo that then becomes a vital part of the graphic documentation. The points measured should be those of most significance for the description of the object so that the survey can be completed in as short a time as possible and with optimum results in terms of the approximation of the considered shape. The formal and material characteristics of the dwellings being studied significantly limit the usefulness of this kind of survey technique. The soft outlines of domed dwellings, the corners of the building rounded by a thick layer of plaster and surface irregularities increase the difficulty of recognizing which points were the most significant for synthesizing the shape of the dwelling units. The topographic techniques used for each dwelling unit are illustrated in the following sheets.

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>>> Scanposition 5.129.944 points

Scanposition 10.032.450 points

All Scanposition 60.841.727 points

Fig. 10: Plan and environment sections. 302

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Topographical survey Joub Maadi The dwelling unit surveyed is surrounded by other buildings/closed by the body of the buildings. It is a system with several single truncated-conic domes (it belongs to the “dome with a flat roof” typology) that is used as a dwelling, for agricultural purposes, as storage and as a livestock shelter. The topographic traverse had three principal vertices (100, 120, 130) and three secondary vertices (110, 140, 150). 20 targets were acquired. Straddles were used to reach the rather narrow spaces outside the unit to ensure a thorough documentation of the morphological and dimensional characteristics of the site. 19 scans were carried out: 4 inside the dwelling cells, 8 in the pertaining courtyard and 7 outside the dwelling unit.

Laser scanning survey Unlike celerimetric surveying (where the point to be measured is selected, collimated through a telescope, and then measured), scanning systems use entirely automatic procedures to enable the rapid acquisition of a huge number of points. Once the instrument is set and positioned, it performs a ‘scan’ of all the surrounding space by sending a laser spot with high frequencies and a very small angular step. In this way, all visible surfaces are sampled, similar to what happens when a paper document is scanned with a flatbed scanner. A laser scanner survey provides a digital model of the object, consisting of all the points measured on the surface of the object: it is

therefore three-dimensional. It is obvious that the correspondence between the object and its model is proportional to the resolution used and to the density of the points. Adequate documentation of the Syrian dwelling units was produced using a laser scanner: the distance never exceeded a few tens of metres in order to obtain an average resolution of about a centimetre. These procedures enabled a great deal of information to be obtained from the cloud of points: the way the various cells aggregate to form a dwelling unit; the internal layout; the pattern of the brickwork used in the construction of the different dome typologies; technological details such as ventilation openings, door frames and niches (Figs. 4-6). The automatism that char-

Fig. 11a: The cooking oven: plan with orthogonal projection of the contour lines, longitudinal and traverse sections. 303

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Laser scanner survey Fig. 11b: A dwelling cell: plan with orthogonal projection of the contour lines; above, plan documenting the type of roof plan; longitudinal, transversal and diagonal sections.

acterizes the measurement phase means that everything that is visible from the scanning position is surveyed: in the final model not only the walls of the dwellings are recognizable but also all the objects found inside: rugs, cushions, shelves and a few pieces of furniture. These objects were not moved prior to the survey to reduce the invasiveness of the teamâ&#x20AC;&#x2122;s presence and to allow the documentation of socio-cultural and anthropological aspects as well (Figs. 7-9). An HDS 6000 (Leica Geosystems) laser scanner, with a rapid rate of acquisition (up to 50.000 points a second) was used: in the survey conditions here described between 3 and 10 minutes were required for each scan. The rapidity of this surveying technique meant that the extreme sensitivity of the laser scanner to environmental conditions and especially to high temperatures

did not have a significant impact. During the three weeks of surveying (from 26th May till 13th June, 2008) on-site 3D scans were taken only in the early hours of the morning before the temperature exceeded the maximum limits for effective operation of the instrument. Scan alignment Each scan is initially acquired in a local system, with the instrument at the origin and centre (intrinsic reference system). The importance of expressing all the metric data in a single reference system, determined by the topographic frame of reference, has already been emphasized. The transformation of the data acquired from all the intrinsic systems to adapt it to the fundamental topographic system takes the name of â&#x20AC;&#x153;scanning alignmentâ&#x20AC;?; this process is carried out using signals placed on the site and surveyed, as described above, as

Fig. 12: Plan and environmental sections. 304

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Topographical survey Oum Aamoud Seghir The dwelling unit examined is closed by the body of the buildings. It is a system with several pseudo-conic domes (Sultan dome typology), some of which are single, others are connected by an arch-way; it is used as a dwelling, for agricultural purposes, for storage and for sheltering animals. The topographic traverse had three principal vertices (100, 200, 300) and four secondary vertices (400, 500, 600, 700). 29 targets were measured. Straddles were created to meet the requirement of measuring easily recognisable points on the scene (either natural or, preferably, targets); these points were then used to roto-translate the range maps acquired with the laser scanner. 27 scans were performed (5 inside the cells, 10 in the pertaining courtyard and 12 outside the dwelling unit). In this case too, the resolution used for data acquisition varied depended on the desired graphic results and information levels.

control points. The coordinates of these signals are therefore known in both the local scanning system and in the topographic system; this makes it possible to determine the roto-translation that has to be applied to all the points of each scan to align them to the topographic system. Signal recognition can take place automatically, thereby speeding up the alignment phase and limiting operator intervention to the verification of the results obtained. If a scan does not have at least three clearly recognizable signals, then natural points can be identified manually.

After the scans have all been aligned it is possible to carry out global compensation: an ICP type algorithm is applied to further reduce any residual distance between corresponding surfaces in adjacent scans. The photogrammetic survey For one of the dwelling units surveyed in the village of Er Raheb it was considered advisable to integrate the detailed geometric information obtained from the 3D scans with other information of a photographic nature. So photogrammetric shoots were performed and then oriented in order to obtain highly accurate ortho-photos of all the elevations of the dwelling. Ortho-

Fig. 13a: A dwelling cell: plan with orthogonal projection of the contour lines; the main elevation; longitudinal, transversal and diagonal sections.

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Earthen Domes and Habitats

Laser scanner survey Fig. 13a: An agricultural cell: plan with orthogonal projection of the contour lines; plan documenting the upward spiral rows of the dome; the main elevation; longitudinal, transversal and diagonal sections.

photos are photographic documents in which perspective deformation and local variations of scale, characteristic of central projection (and of photography), are corrected zone by zone. It is possible to read dimensions and evaluate surfaces from these ortho-photos in a similar way to an elevation represented in orthogonal projection. Another benefit comes from the complete documentation of the objects being studied which is not confined to the corners or the lines of discontinuity typical of conventional representation; the surfaces of the objects are thus described with photographic quality representing the details of materials, brick-work patterns and the state of conservation. Photogrammetry is a technique that enables metric information to be de-

rived from photographic images when appropriate procedures are adopted. There are three distinct phases in a photogrammetric survey: shooting, orientation and restitution. Taking photograms Photographs are taken. The images used are also called photograms to emphasise their metric valence. It is obviously important that high quality photographic shots be taken and careful attention should be given to the lighting of the object even when, as was the case in Syria, the constant presence of bright sunshine makes uniform lighting difficult. The positions from which the photograms were taken was planned to ensure that, as far as possible, the distance between the camera and the object re-

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Earthen Domes and Habitats

Fig. 14: Plan with orthogonal projection of the contour lines; the main elevation; longitudinal, transversal and diagonal sections.

Topographical survey Er Raheb (a). Two different dwelling units were surveyed in this village; for the sake of simplicity we will call them ER(a) and ER(b). ER(a) is an open dwelling unit with two pseudo-conic domes (Sultan dome). It was not possible to survey the interior of a dwelling unit. The topographic traverse had three principal vertices (1000, 2000, 3000). 24 targets were used: 16 for referencing the range map and 8 for realising rectified images and orthophotos. 7 scans were carried out: 4 outside and 3 inside the dwelling unit.

mained constant and that the images were realized in a scale that allowed details of interest, such as wall structure and the presence of cracking, to be read. Some shots were taken sequentially with the axis of the camera almost orthogonal to the elevation (so-called flight strips), others, for instance the shots of the corners of the building, were convergent. Orientation of the photograms â&#x20AC;&#x2DC;Orientationâ&#x20AC;&#x2122; is the process used later to reconstruct the position and orientation of the camera when the shots were taken. To attain this objective it is essential that the coordinates of certain control points found on the image

be known. Given the difficulty of identifying natural points on structures of this type, appropriately placed signals were used. The calculation of the orientation parameters is based on the condition of colinearity that exists between all the points of the object and all the corresponding image points at the moment when the photogram is taken: the alignment between object points, the photographic centre and image points can in fact be expressed analytically (Fig. 17). Restitution and orthoprojection Once the position of the camera (or rather of all the photograms) has been redefined with respect to the object it is possible to imagine the re-projection of one light ray for each pixel of the image, in the opposite direction

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Earthen Domes and Habitats

Fig. 15: Er Raheb(b), section profiles from the points model.

Laser scanner survey

to the original photogram. If only one image is available obviously only one star of directions can be defined and no information can be obtained as to the position of all the object points. If, however, there are at least two oriented images a star of directions will depart from each one and the rays relative to the homologous points (i.e. the same object point taken in different images) will meet on the object point that had generated the corresponding image points when the photogram was taken. Photogrammetric restitution consists in identifying homologous points on at least two oriented photograms to enable the position of the corresponding point on the object to be calculated. In order to make orthophotos, a shape model of the object is required as well as the oriented photograms; in the case of the dwelling unit of Er Raheb the form model was obtained from the points model pro-

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Earthen Domes and Habitats

Fig. 16: Er Raheb (a), orthophotos relative to the four elevations of the form model of the entire dwelling unit.

Topographical survey Er Raheb (b) ER(b) is an open dwelling unit with two pseudo-conic domes (Sultan dome). It was possible to survey the interior of ER(b) to study the qualitative and quantitative aspects of the isolated-type construction system composed of two cells connected by an archway. The topographic traverse had four principal vertices (100, 200, 300, 500) and one secondary vertex (400) for reading the signals placed inside the dwelling unit. 18 targets were used: these were essential during the alignment phase of the points clouds generated by the scanning systems. 8 scans were carried out from different positions: 5 outside, 2 inside and 1 uniting inside and outside. For obvious reasons a higher resolution was used for the outside scans than for those carried out inside; this was quantified on a grid made up of points placed at 0.5 cm intervals when the object was 10 m away and placed at up to 3 cm intervals at a distance of 50 m.

duced during scanning (Fig. 18). The retro-projection of an oriented photogram takes place in such a way that each ray of the star of directions meets the form model of the object: the objective in this instance is not the reconstruction of the form of the building, which should already be known, but the calculation of the ‘photographic coloration’ to attribute to each tiny portion of the surface of the object. Orthogonal viewpoints relative to the four elevations of the form model of the entire dwelling unit were set up and the corresponding orthophotos were calculated (Fig. 16).

The graphic output The three-dimensional points model obtained after aligning all the 3D scans constitutes a real database: it is an extremely dense and sufficiently accurate ‘information depot’ from which all the required graphic output can be successively derived. The wealth of information contained in these models is valorised by the possibility of visualizing and exploring them interactively with the appropriate software. The model acquires the role of significant referent of the object, and it is possible to observe the model as if it were the object itself: the mod-

309

Earthen Domes and Habitats

Fig. 17: Er Raheb (a), orientation of the photograms. Fig. 18: Er Raheb (a), oriented photograms and the points model produced during scanning.

Laser scanner survey

el rather than the building itself can be deployed for dimensional evaluation, analysis of constructive details and anthropological considerations, with all the advantages that derive from the possibility of operating at different times and in different places. A first approximate technical classification of the graphic output that was obtained from the points cloud distinguishes the bi-dimensional documentation from the tri-dimensional and the raster documentation (composed of images) from the vectorial. A standard â&#x20AC;&#x153;from the general to the detailâ&#x20AC;? approach was adopted for determining the information presented in the various documents proceeding, for example, from the realization of environmental sections which insert an entire dwelling unit in its context, to representations of the details of characterizing typological elements, such as the

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Earthen Domes and Habitats

profile of the dome, the perimeter base of the walls, the base of the pendentive, the brickwork structure and the openings. Section profiles and contour lines An effective way of synthesizing the three-dimensional conformation of the dwelling units in vectorial and bi-dimensional output is to extract section profiles from the points model (Fig. 15): a very thin layer of the points cloud, delimited by a couple of parallel planes which can be either horizontal or vertical, is isolated and then exported and vectorialized using CAD software. Environmental sections for dwelling units in Oum Aamoud Seghir and Joub Maadi were created using this method. Other units were investigated at the scale of the cell, realizing one horizontal section (at a quota of about 1 m from the floor and vertical sections (longitudinal, transversal and diagonal). While the longitudinal and transversal sections, associated with the plan, reflect the standard bi-dimensional documentation that is capable of completely describing the three-dimensional space of the dwelling units, the addition of the diagonal section takes into consideration the requirements of structural analysis to obtain precise information on the corners of the square box at the base. Representations less synthetic than those obtained from sections following coordinated planes were constructed using contour lines. These representations were indispensable because it was particularly difficult to highlight the lines of discontinuity on the objects examined in any other way. The equidistance of the contours was differentiated as a function of the morphological complexity of the building portions analyzed: profiles were extracted every 50 cm starting from the impost of the dome and finishing with the closing element (tantour), integrated by profiles every 10 cm for the entire pendentive. Structural analysis has in fact been concentrated on this element, which unites the square perimeter and the circle of the impost of the dome. Orthogonal images from points cloud To complete the geometric-dimensional information provided by the section profiles, all the documentation was integrated with orthogonal images of the points model; although these images are not really photographic images they manage to effectively evoke the material and chromatic characteristics of all the elements that appear in these representations. Surface models The model acquired using 3D scanning is, inevitably, not entirely complete since it is made up of points but it can be made continuous by using ‘triangulation’ to create a surface model (Figs. 19-20). Triangulation generates a

‘mesh’ and the minimum elements of this mesh are no longer undifferentiated; but are organized following a definite topological structure. The minimum element of the model is made up of triangular-shaped portions that describe the object with a level of detail inversely proportional to their size (the smaller the element, the more of them there are). The geometric simplification of a model means that superficial details are obliterated thereby making the model more manageable. Surface models were prepared for both the dwelling units surveyed at Er Raheb. Solid models Finally, reduced-scale solid models are an effective support for projects involving communication and divulgation: they can be understood without the intermediation of data processing systems which increases the number of potential users. A 1:20 scale was used for the models of the dwelling units of the village of Er Raheb: this ensures that the final model, made up of a series of thin layers, retains a high degree of detail, making it possible, for example, to distinguish the different types of wall texture or to recognize minute details. List of References Bonora, V., Cruciani Fabozzi, G. & Tucci, G. 2008, ‘The use of 3D Scanning and Rapid Prototyping for the Documentation, Conservation and Communication of Archaeological Remains: a Recent Experience in the Sanctuary of S. M. del Lavello (Lecco, Italy)’, DMACH 2008 conference, 3 – 6 November 2008, Petra University, Amman, Jordan. Bonora, V. & Tucci, G. 2007, ‘Il laser scanner terrestre e il rilievo dei Beni Culturali’, Sistemi a scansione per l’architettura e il territorio, Sacerdote F. & Tucci G. (eds), Alinea, Firenze, pp. 89-123. Besenval, R. 1984, Technologie del la voûte dans l’Orient Ancien, Éditions Recherche sur les Civilisations, Paris. Bucalossi, L. 2009, 3D scanning and digital photogrammetry for the documentation of raw land in villages north of the region of Aleppo (Syria), Licence Thesis, Faculty of Architecture, University of Florence, Florence. Migliari, R. 2004, ‘Per una teoria del rilievo architettonico’, Disegno come Modello, Migliari R. (ed.), Roma. Rapoport, A. 1969, House Form and Culture, Milwaukee. Tunca, Ö., Meunier, J. M., Lamisse, J. Cl. & Stockeyr, E. 1991, ‘Architecture de terre – Architecture mère: portrait de deux villages en Syrie du Nord’, Assyriologie et archéologie de l’Asie antérieure, Université de Liège, Liège. Tucci, G., Bonora, V. & Nobile, A. 2009, ‘Innovative survey methods for the digital documentation of vernacular architectural heritage in Syria’, Proceedings of the CIPA 2009, XXII International Symposium ‘Digital Documentation, Interpretation & Presentation of Cultural Heritage’, Kyoto. Tucci, G., Bonora, V., Crocetto, N. & Nobile, A. 2009, ‘Misurare l’irregolare: applicazioni della geomatica alla tutela e al recupero di un habitat rupestre a Gravina in Puglia’, Proceedings of the ASITA 2009 XIII Congress, Bari. Tucci, G., Bonora, V., Sacerdote, F., Costantino, F. & Ostuni, D. 2004, ‘From the acquisition to the representation: quality evaluation of a close range model’, XXth ISPRS Congress, Istanbul, vol. XXXV, part B5.

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Fig. 19: Er Raheb(b), surface model. Fig. 20: Er Raheb(a), surface model.

Fig. 21: Er Raheb(a), solid model. Fig. 22: Er Raheb(b), solid model.

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The earthen architectures are realised with materials constituted by a prevailing mineral component and a possible organic fraction (original or addictivated). The composition (proportion and type of clay minerals and proportion of coarse fraction) determines the behaviour of the earth, in particular its plasticity, shrinkage, workability, mechanical characteristics and durability of the artefacts. The prevailing mineral component is constituted by a fine granulometry fraction mainly composed by clay minerals (which have dimensions < 4 micron) and by a coarse granulometry fraction (silt, sand and gravel fractions) composed by rock fragments and non argillaceous minerals. In order to investigate these characteristics and the possible processing of the raw material in the production of bricks and mortars, different kind of earthen building elements have been taken from the corbelled domes buildings of different villages: - bricks (Fig.1), - masonry mortars (Fig. 2), - external plasters (Fig. 3), - internal plasters (Fig. 4), - plaster finishing (Fig. 5-6). Moreover the composition of different whitewashings (Fig 7) and the composition of the stone utilised (after disaggregation in water) for the production of the material for whitewashing (Fig 8), have been investigated. Analytical methods The following analyses have been performed: - determination of the principal mineralogical composition through X ray diffraction; - determination of the amount of calcite through calcimetry; - determination of the clay minerals composition through X ray diffraction.

Institute for the Conservation and Enchancement of Cultural Heritage, CNR, Italy

List of the samples village: Fejdane A B D E F G H1 H2 L M N

Description mortar brick external plaster internal plaster (finishing layer) internal plaster (under E) internal plaster (under F) finishing layer of the external plaster finishing layer of the external plaster stone for whitewashing whitish plaster earth to make bricks

village: Oum Aamoud Seghir P XX XY

Description brick (dome) external plaster external plaster

village: Rasm Amhd Q1 Q2 Q3 R S T U V Z X J J

Description internal plaster ( whitewashing) internal plaster (finishing layer,under Q1) internal plaster (under Q2) masonry mortar (basalt blocks basement) external plaster (dome) external plaster (dome) brick masonry mortar (dome) stone for whitewashing (given) brick brick (vertical masonry) brick (dome)

village: Al Rouihieb AA BB1 BB2 CC CC1 DD EE EE1 FF FF1

Description internal plaster, whitewash (dome) internal plaster internal plaster (whitewash) internal plaster whitewash of CC internal plaster external plaster (base of the vertical masonry) grey finishing of EE brick masonry mortar

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Earthen Domes and Habitats

The archaeometric analysis of building materials

Fabio Fratini

314

village:Joub Maadi

Earthen Domes and Habitats

GG HH II LL

Description brick masonry mortar external plaster (1st layer) external plaster (1st layer)

village: Rasm Al Boughere MM NN OO PP

Description brick masonry mortar brick stone for whitewashing

village: Rbaiaa QQ QQ1 RR SS TT

Description brick masonry mortar of QQ masonry mortar (dome) brick stone for whitewashing

village: Oum Aamoud Kebir WWW NNN OOO PPP QQQ RRR SSS SSS1

Description earth to make bricks whitewash internal plaster external plaster (north side) external plaster (east side) brick brick masonry mortar of SSS

village: Mazraat Al Rouiaieb AAA1 AAA2 BBB1 BBBB2

Description external plaster whitewash of AAA1 internal plaster finishing of BBB1

village: Srouj CCC DDD EEE FFF

Description internal plaster (degraded) external plaster (degraded) masonry mortar brick

village: Meksar Shamlei TTT UUU III

Description brick (dome) external plaster (degraded) masonry mortar

Fig. 1: Earthen brick with evident gravel fraction and scarce fibres. Fig. 2: Masonry mortar with evident finer granulometry and absence of fibres Fig. 3: Plaster from the inside of a building with evident straw addition Fig. 4: Multy layerd plaster from outside

Fig. 5: Whitish finishing layer Fig. 6: Section of internal plaster and whitish finishing layer Fig. 7: Whitewashing Fig. 8: Stone utilised in the production of the material for the whitewashing with an evident chert nodulus

315

Earthen Domes and Habitats

General considerations The raw material utilised for the realisation of bricks and mortar both for masonry and plastering is the local earth taken nearby each village. Despite the distance among the villages, it display more or less the same composition depending on the lithological homogeneity of the territory. It is a marly clay (namely a clay rich in calcite) with an amount of clay minerals variable from 30 to 50 %. The clay minerals composition displays always a little amount of swelling clay minerals. The coarser fraction is made mainly of calcareous rock fragments which range from gravel (1-2 cm) to sandy (0.02-2 mm) and silty granulometry (2-20 microns). According to this composition and to the observed granulometry this earth can be defined as a quite lean earth. Regarding the suitability of this material for the production of unfired bricks and mortar, it should be noticed that its quite lean characteristics determines low cohesion of the dried product. Moreover the presence of a certain amount of swelling clay minerals (smectite, illite-smectite) can affect the durability of the material when exposed to humidity. With reference to the different products realised with this raw material (bricks, masonry mortars and mortar for plasters sometimes it is possible to observe that the masonry mortar is finer grained due to a depuration process from the coarser fraction. Nevertheless differences can be observed due to the addition of vegetal fibres (namely straw), absent in the masonry mortars, scarce in the bricks and abundant in the plasters. Regarding the finishing layers of the plasters, usually they display a thickness of about 0.5 cm but some differences can be observed in their composition. Two types have been distinguished, a mix of lime, depurated earth and straw (observed in an internal plaster) and a mix of lime, gypsum depurated earth and straw (observed in an external new plaster). Regarding the whitewash, two different compositions have been evidenced, one made only of lime and another made of a mix of lime and gypsum. As a matter of fact, the stone that is disaggregated in water in order to obtain the powder utilised for the whitewashing, is a soft fine grained limestone with rare chert nodules.

The earth is a marly clay with an amount of clay minerals of about 25-35 %. The clay minerals composition display a little amount of swelling clay minerals. The coarser fraction is made mainly of calcareous rock fragments which range from gravel (1-2 cm) to sandy (0.02-2 mm) and silty granulometry (2-20 microns). This earth can be defined as a quite lean earth. It is not possible to emphasise any particular difference among the composition of the earth utilised to make the bricks, the bricks themselves and the plaster mortar both for inside and outside. On the contrary sometimes it is possible to observe that the masonry mortar is finer grained due to a process of depuration of the coarser fraction. Moreover these products can be distinguished for the addition of vegetal fibres (namely straw), absent in the masonry mortars and scarce in the bricks and abundant in the plasters. The stone that is disaggregated in water in order to obtain a powder utilised for the whitewashing, is a soft fine grained limestone with rare chert nodules but as a matter of fact the whitewash present over the plasters is made of a mix of lime and gypsum.

316

Earthen Domes and Habitats

village: Oum Aamoud Seghir Principal mineralogical composition Denomination P -brick XX -plaster XY -plaster

fibres tr straw straw

Quartz 5 5 5

Feldspars 10 10 5

Calcite 60 55 55

Gypsum -

clay minerals 25 30 35

Clay mineral composition

Fig. 9: Map of the villages of selected samples

Denomination P -brick XX -plaster XY -plaster

kaolinite 20 25 20

illite 35 35 40

clorite 20 20 15

illite-smectite 25 20 25

smectite -

village: Oum Aamoud Kebir Principal mineralogical composition Denomination WW-earth for bricks NNN -whitewash OOO -plaster PPP -plaster QQQ -plaster RRR -brick SSS -brick SS1 -mortar

fibres straw straw straw straw -

quartz 5 tr 5 5 5 5 5

feldspars 5 10 tr 10 10 5 10

calcite 60 40 60 60 60 50 55 55

gypsum 60 -

clay minerals 30 30 35 25 35 35 30

Composition of the clay minerals Denomination WWW-earth OOO -plaster PPP -plaster QQQ -plaster RRR -brick SSS -brick SS1 -mortar

kaolinite 25 25 25 25 20 20 25

illite 20 20 25 25 25 20 20

clorite 20 15 20 15 15 15 15

illite-smectite 15 20 15 15 15 20 15

smectite 20 20 15 20 25 25 25

The earth utilised in the buildings is a marly clay with an amount of clay minerals of about 25-35%. The clay minerals composition display a little amount of swelling clay minerals. The coarser fraction is made mainly of calcareous rock fragments which range from gravel (1-2 cm) to sandy (0.02-2 mm) and silty granulometry (2-20 microns). This earth can be defined as a quite lean earth. It is not possible to emphasise any particular difference among the composition of the bricks and the plaster mortar for outside. On the contrary sometimes it is possible to observe that the masonry mortar is finer grained due to a process of depuration from the coarser fraction. Moreover these products can be distinguished for the addition of vegetal fibres (namely straw), absent in the masonry mortars, scarce in the bricks and abundant in the plasters.

village: Fejdane

317

Denomination A -masonry mortar B -brick D -plaster E -finishing layer F -plaster, under E G -plaster, under F H1 -finishing layer H2 -finishing layer L -stone for whitewash M -whitish plaster N -earth

fibres tr straw straw straw straw straw straw -

Quartz 5 5 5 10 5 tr tr tr 5

Feldspars 10 5 5 5 10 tr tr tr 5

Calcite 50 45 50 80 45 40 50 50 95 50 45

Gypsum 30 30 30 -

Earthen Domes and Habitats

Principal mineralogical composition clay minerals 35 45 40 20 40 45 20 20 5 20 45

Clay mineral composition Denomination A -masonry mortar B -brick D -plaster E -finishing layer F -plaster, under E G -plaster, under F H1 -finishing layer H2 -finishing layer M -finishing layer N -earth to make bricks

Kaolinite 20 15 20 25 20 15 20 20 25 20

illite 25 25 25 20 25 30 25 30 20 25

clorite 15 20 20 15 15 20 20 20 15 15

illite smectite 25 20 20 20 25 20 20 20 20 20

smectite 15 20 15 20 15 15 15 10 20 20

The earth utilised in the buildings is a marly clay (namely rich in calcite) with an amount of clay minerals of about 35-45 %. The clay minerals composition display a little amount of swelling clay minerals. The coarser fraction is made mainly of calcareous rock fragments which range from gravel (1-2 cm) to sandy (0.02-2 mm) and silty granulometry (2-20 microns). This earth can be defined as a quite lean earth. It is not possible to emphasise any particular difference among the composition of the earth utilised to make the bricks, the bricks themselves, and the plaster mortar both for inside and outside. On the contrary sometimes it is possible to observe that the masonry mortar is finer grained due to a process of depuration of the coarser fraction. Moreover these products can be distinguished for the addition of vegetal fibres (namely straw), absent in the masonry mortars, scarce in the bricks and abundant in the plasters. Regarding the finishing layers of the plasters, they display a thickness of about 0.5 cm and they can be made both by a mix of lime, depurated earth and straw (observed in an internal plaster) or by a mix of lime, gypsum depurated earth and straw (observed in an external new plaster). The stone that is disaggregated in water in order to obtain a powder utilised for the whitewashing, is a soft fine grained limestone with rare chert nodules.

Fig. 10: Plaster maintenance in Cheik Hilal

village: Rasm Amhd Principal mineralogical composition Denomination Q1 -whitewash Q2 -finishing layer Q3 -plaster R -masonry mortar S -plaster T -plaster U -brick V -masonry mortar Z -stone for whitewash X -brick Y -brick J -brick

fibers straw straw straw straw straw straw straw straw

Quartz 5 5 5 10 10 5 5 5 10

feldspars tr tr tr tr tr tr tr tr tr

Calcite 40 80 60 65 55 60 60 65 90 55 60 55

Gypsum 60 -

clay minerals 20 40 30 40 30 30 30 10 40 35 35

Fig. 11: Plaster maintenance in Oum Aamoud Seghir 318 Earthen Domes and Habitats

Composition of the clay minerals kaolinite 20 15 15 20 15 20 15 20 15 20

illite 40 35 45 45 40 40 45 40 35 45

clorite 15 20 10 10 10 15 10 15 20 10

illite-smectite 10 15 15 15 20 15 15 15 20 15

smectite 15 15 15 10 15 10 15 10 10 10

The earth utilised in the buildings is a marly clay with an amount of clay minerals of about 30-40%. The clay minerals composition display a little amount of swelling clay minerals. The coarser fraction is made mainly of calcareous rock fragments which range from gravel (1-2 cm) to sandy (0.02-2 mm) and silty granulometry (2-20 microns). This earth can be defined as a quite lean earth. It is not possible to emphasise any particular difference among the composition of the bricks and the plaster mortar both for inside and outside. On the contrary sometimes it is possible to observe that the masonry mortar is finer grained due to a process of depuration of the coarser fraction.. Moreover these products can be distinguished for the addition of vegetal fibres (namely straw), absent in the masonry mortars, scarce in the bricks and abundant in the plasters. Regarding the finishing layers of the plasters, they display a thickness of about 0.5 cm and they are made by a mix of lime, depurated earth and straw (observed in an internal plaster). The stone that is disaggregated in water in order to obtain a powder utilised for the whitewashing, is a soft fine grained limestone with rare chert nodules but as a matter of fact the whitewash present over the plasters is made of a mix of lime and gypsum. village: Rbaiaa Principal mineralogical composition Denomination QQ -brick QQ1-masonry mortar RR -masonry mortar SS -brick TT -stone for whitewash

fibres straw -

quartz 5 10 10 5 -

feldspars 10 10 10 10 -

calcite 40 35 35 40 95

gypsum -

clay minerals 45 45 45 45 5

Composition of the clay minerals Denomination QQ -brick QQ1 -masonry mortar RR -masonry mortar SS -brick

kaolinite 25 30 25 20

illite 25 30 25 25

clorite 20 25 15 20

illite-smectite -

smectite 30 35 35 35

The earth is a marly clay with an amount of clay minerals of about 40-55%. The clay minerals composition display a little amount of swelling clay minerals. The coarser fraction is made mainly of calcareous rock fragments which range from gravel (1-2 cm) to sandy (0.02-2 mm) and silty granulometry (2-20 microns). This earth can be defined as a quite lean earth. It is not possible to emphasise any particular difference among the composition of the bricks and that of the masonry mortar. Therefore we can argue that no particular selection of the earth has been performed in order to realise these different products. On the contrary these products can be distinguished for the addition of vegetal fibres (namely straw), absent in the masonry mortars and scarce in the bricks. The stone that is disaggregated in water in order to obtain a powder utilised for the whitewashing, is a soft fine grained limestone with rare chert nodules. village: Al Rouihieb Principal mineralogical composition Denomination AA -whitewash BB1 -plaster BB2 -whitewash CC -plaster CC1 -whitewash DD -plaster EE -plaster EE1 -grey finishing FF -brick FF1 -masonry mortar

fibres straw straw straw straw straw -

Quartz 5 5 5 5 5 5

Feldspars 10 10 10 10 5 10

Calcite 95 55 95 50 95 55 55 40 60 55

Gypsum 60 -

clay minerals tr 30 tr 35 tr 30 30 30 30

Clay mineral composition Denomination BB1 -plaster CC -plaster DD -plaster EE -plaster FF -brick FF1 -masonry mortar

kaolinite 15 20 15 15 20 20

illite 50 55 55 50 45 50

clorite 10 15 20 10 15 10

illite-smectite 25 10 20 25 20 20

smectite -

The earth is a marly clay with an amount of clay minerals of about 30-40 %. The clay minerals composition display a little amount of swelling clay minerals. The coarser fraction is made mainly of calcareous rock fragments which range from gravel (1-2 cm) to sandy (0.02-2 mm) and silty granulometry (2-20 microns). This earth can be defined as a quite lean earth. It is not possible to emphasise any particular difference among the composition of the bricks and the plaster mortar both for inside and outside. On the contrary sometimes it is possible to observe that the masonry mortar is

319

Earthen Domes and Habitats

Denomination Q2 -finishing layer Q3 -plaster R -masonry mortar S -plaster T -plaster U -brick V -masonry mortar X -brick Y -brick J -brick

320

Earthen Domes and Habitats

finer grained due to a process of depuration of from the coarser fraction.. Moreover these products can be distinguished for the addition of vegetal fibres (namely straw), absent in the masonry mortars, scarce in the bricks and abundant in the plasters. The stone that is disaggregated in water in order to obtain a powder utilised for the whitewashing, is a soft fine grained limestone with rare chert nodules. The whitewash present over the plasters is made of lime. village:Joub Maadi Principal mineralogical composition Denomination GG -brick HH -masonry mortar II -plaster LL -plaster

fibres straw straw straw

quartz 5 10 5 10

feldspars 5 5 5 5

calcite 40 45 40 45

gypsum -

clay minerals 50 40 50 40

Composition of the clay minerals Denomination GG -brick HH -masonry mortar II -plaster LL -plaster

kaolinite 30 25 30 30

illite 30 35 30 35

clorite 20 15 15 15

illite-smectite 20 25 25 20

smectite -

The earth utilised in the buildings is a marly clay with an amount of clay minerals of about 40-50%. The clay minerals composition display a little amount of swelling clay minerals. The coarser fraction is made mainly of calcareous rock fragments which range from gravel (1-2 cm) to sandy (0.02-2 mm) and silty granulometry (2-20 microns). This earth can be defined as a quite lean earth. It is not possible to emphasise any particular difference among the composition of the bricks and the plaster mortar for outside. On the contrary sometimes it is possible to observe that the masonry mortar is finer grained due to a process of depuration of the coarser fraction. Moreover these products can be distinguished for the addition of vegetal fibres (namely straw), absent in the masonry mortars and scarce in the bricks. village: Rasm Al Boughere Principal mineralogical composition Denomination MM -brick NN -masonry mortar OO -brick PP -stone for whitwash

fibres straw -

quartz 7 8 5 -

feldspars tr tr tr -

calcite 55 55 50 95

gypsum clay minerals 35 35 45 tr

Composition of the clay minerals Denomination MM -brick NN -masonry mortar OO -brick PP -stone for whitwash

kaolinite 15 20 20 15

illite 40 40 35 35

clorite 15 10 10 15

illite-smectite 15 20 25 25

smectite 15 10 10 10

The earth utilised in the buildings is a marly clay with an amount of clay minerals of about 35-45%. The clay minerals composition display a little amount of swelling clay minerals. The coarser fraction is made mainly of calcareous rock fragments which range from gravel (1-2 cm) to sandy (0.02-2 mm) and silty granulometry (2-20 microns). This earth can be defined as a quite lean earth. It is not possible to emphasise any particular difference among the composition of the bricks and that of the masonry mortar. Therefore we can argue that no particular selection of the earth has been performed in order to realise these different products. On the contrary these products can be distinguished for the addition of vegetal fibres (namely straw), absent in the masonry mortars and scarce in the bricks. The stone that is disaggregated in water in order to obtain a powder utilised for the whitewashing, is a soft fine grained limestone with rare chert nodules. village: Mazraat Al Rouiaieb Principal mineralogicalcomposition Denomination AAA1 -plaster AAA2 -whitewash BBB1 -plaster BBBB2 -finishing

fibres straw straw straw

quartz 5 5 -

feldspars 5 5 -

calcite 65 50 60 80

gypsum 50 -

clay minerals 25 30 20

Composition of the clay minerals Denomination AAA1 -plaster BBB1 -plaster BBBB2 -finishing

kaolinite 25 25 20

illite 40 35 35

clorite 20 20 20

illite-smectite 15 20 25

smectite -

The earth is a marly clay with an amount of clay minerals of about 30-40 %. The clay minerals composition display a little amount of swelling clay minerals. The coarser fraction is made mainly of calcareous rock fragments which range from gravel (1-2 cm) to sandy (0.02-2 mm) and silty granulometry (2-20 microns). This earth can be defined as a quite lean earth. It is not possible to emphasise any particular difference between the composition of the mortar of the internal and external plaster. Therefore we can argue that no particular selection of the earth has been performed in order to realise these different products. Regarding the finishing layers of the plasters, they display a thickness of about 0.5 cm and they are made by a mix of lime, depurated earth and straw (observed in an internal plaster).

village: Srouj

village: Meksar Shamlei

Denomination CCC -plaster DDD -plaster EEE -masonry mortar FFF -brick

fibres straw straw straw

Quartz 5 5 5 5

Principal mineralogical composition Feldspars 5 5 5 5

Calcite 40 35 40 40

Gypsum -

clay mimerals 50 55 50 50

Composition of the clay minerals Denomination CCC -plaster DDD -plaster EEE -masonry mortar FFF -brick

kaolinite 25 30 30 20

illite 40 45 40 40

clorite 10 5 5 10

illite-mectite 25 20 25 30

smectite -

The earth is a marly clay with an amount of clay minerals of about 50-55 %. The clay minerals composition display a little amount of swelling clay minerals. The coarser fraction is made mainly of calcareous rock fragments which range from gravel (1-2 cm) to sandy (0.02-2 mm) and silty granulometry (2-20 microns). This earth can be defined as a quite lean earth. It is not possible to emphasise any particular difference among the composition of the bricks and the plaster mortar both for inside and outside. On the contrary sometimes it is possible to observe that the masonry mortar is finer grained due to a process of depuration of the coarser fraction. Moreover these products can be distinguished for the addition of vegetal fibres (namely straw), scarce in the bricks and abundant in the plasters.

Denomination TTT -brick UUU -plaster III -masonry mortar

fibres straw straw -

quartz tr tr tr

feldspars tr tr tr

calcite 65 65 70

gypsum -

clay minerals 35 35 30

Composition of the clay minerals Denomination TTT -brick UUU -plaster III -masonry mortar

kaolinite 30 35 30

illite 35 30 30

clorite 15 15 20

illite-smectite 20 20 20

smectite -

The earth is a marly clay with an amount of clay minerals of about 30-35 %. The clay minerals composition display a little amount of swelling clay minerals. The coarser fraction is made mainly of calcareous rock fragments which range from gravel (1-2 cm) to sandy (0.02-2 mm) and silty granulometry (2-20 microns). This earth can be defined as a quite lean earth. It is not possible to emphasise any particular difference among the composition of the bricks and the plaster mortar for outside. Therefore we can argue that no particular selection of the earth has been performed in order to realise these different products. On the contrary these products can be distinguished for the addition of vegetal fibres (namely straw), scarce in the bricks and abundant in the plasters. Fig. 12: Different finishing layers of domes in Oum Aamoud Seghir

Earthen Domes and Habitats

Principal mineralogical composition

321

322

Earthen Domes and Habitats

The steppes and the uplands of Northern and Central Syria, the Arid Margins, (Fig.1) offer few resources immediately available for construction. With earth available everywhere and in large quantities, often in the face of scarcity of wood and stone, populations occurring in these regions have achieved habitats consisting of small villages with houses built entirely in earth. In these circumstances the technique of earthen brick masonry or adobe (albeit supplemented by the technique of stone masonry), characterized by a highly technical and cultural plasticity, has adapted to different environments, seen many variations, and different types can be identified. Architecture and environment There is a cultural diversity resulting from the variety of local resources available, the geomorphology of the places (Fig. 2), the position in relation to roads, the knowledge of the builders, the subjectivity that goes to make each individual village. Differing modes of integrating basalt stone or limestone or wood in relation to their availability generate technical solutions, forms, aspects, and colours of the architecture in each village. Villages like Rbaiaa, Rasm Hamd and Cheikh Hilal were built on the ruins of ancient villages of the Byzantine period, effectively used as quarries for building materials (Fig. 4). In villages such as Oum Aamoud Kebir, the earth is mined from alluvial deposits in the riverbeds of seasonal torrents: the people of the villages know the areas where earth to make the bricks can be found (leben trab, local name of earthen bricks, adobe): a clay soil containing little sand but with an amount of gravel. The manufacture of bricks (Fig. 3) is still today a family production under the supervision of an experienced builder, the muallem, who then coordinates the site and builds the dome. Preparation of the earth mix is done by the men, while women shape the bricks with the help of a wooden form: the involvement of the whole family in the construction process (collectively gath elleben), which also involves children with different tasks depending on their ages, significantly reducing the cost of the bricks.

University of Florence, Italy

The earthen masonry technique (adobe) is integrated, for buildings of modest structural and functional importance, with the technique of cob, which is an in situ, hand-modeled earthen wall. The mixture in all cases (adobe and cob, mortars and plasters) is prepared with earth, water and vegetal fibres, or wheat and barley straw, grown around the village, using coarse and knobbly straw for the bricks and sieved straw for the plaster.

Fig. 1: Map of distribution of building materials in study areas

wood limestone basalt stone

limestone

323

Earthen Domes and Habitats

Building culture of corbelled dome architecture

Silvia Onnis Letizia Dipasquale Mirta Paglini

do meet certain requirements such as reduction of maintenance needs and identification with the urban and modern way of life, but they fail, however, in other more important requirements such as hygrothermal comfort, energy efficiency and general sustainability: environmental, economic and cultural.

324

Earthen Domes and Habitats Fig. 2: Context: village built in earth and local stone. Fig. 3: Manufacture of bricks.

Load bearing materials such as wood are more difficult to find, and if not existent in the outskirts of the village, they are purchased in Aleppo or Sfire1: the wood is usually a type called Hor, inexpensive, but not so strong. All kinds of wooden materials are used, ranging from the branches of thorn bushes (Fig. 7) to cane, or hasal, collected in the area of the Lake Jabboul in May. The availability of stone is no less important in determining constructive solutions: there are areas rich in limestone (Fig. 5) and areas where the dark tone of basalt is a major characteristic of the architectural environment (Fig. 6). In these conditions of scarce resources, paradoxically, the availability of a material such as earth, thanks to its ability to integrate other materials and its cultural plasticity, results in a high level of cultural diversity as regards building techniques. New industrial materials have been introduced in the last decades for their ease of use and connotation of modernity: using a smaller part of the traditional architectural knowledge (design and construction). These materials 1

Daker 1984, Ghiyas 1984

The building system The house of the villages of Northern Syria, in its most common form, is an introverted court house, organized around a central empty space enclosed by a fencing wall (Figs. 8-9). The units (cells), making up the house and meeting the various needs of the family, are distributed along the sides of the courtyard. We may identify a hierarchy of the units determined by function, expressed by the size and shape of the unit, but also by the degree of complexity of construction techniques and the level of finish. Technical solutions express the function and importance of the construction: the domes of residential units are built with care and regularity, while complementary elements (fencing walls, domes of service units) are built with different techniques, simpler or more suited to available materials. Consequently, the construction of the dome for housing is generally entrusted to muallem, while the smaller buildings and service facilities are normally built by the inhabitants of the house, particularly by women and older children. The basic element for housing is usually a double unit made up of two square cells, with an internal length of about 4 meters each side, each cell covered by a dome, and communicating through an arch, called qantara or nhit if made with stones. The building processes Once the location and orientation are determined, the perimeter of the building is traced. The mason digs until he finds a solid layer of soil (average depth 40-60 cm) and builds the foundation with stones and earthen mortar. Above

325

Earthen Domes and Habitats

Fig. 4: Tell used as quarry for building materials.

Fig. 5: Limestone.

Fig. 6: Basalt stone.

Fig. 7: An example of wooden materials.

BASAMENT WALL

foundation socket

ELEVATION WALL

stone wall earthen brick wall

PENDENTIVE DOME

CONSTRUCTION WITH DOME

Earthen Domes and Habitats

1. CONSTRUCTION WITH DOME 2. CONSTRUCTION WITH FLAT ROOF OR LOW-SLOPE ROOF 3. SMALL COB DOMES 4. FENCE WALLS OF THE COURT 5. OVEN AND MASTABA

1 4

TOP OF THE DOME

ARCHES AND LINTELS OPENINGS EXTERNAL FINISHES

INTERNAL FINISHES

tantour flat roof earthen brick arches stones arches lintels openings: trilitic system doors and windows (frames) ventilation holes intermediate coat finishing coat limewash floor internal plaster and painting decorations niches fixed furnitures

2 3

Fig. 8: Introverted court house in ‘Sultan dome’ area. Fig. 9: Domes with flat roofs.

CONSTRUCTION WITH FLAT ROOF OR LOW -SLOPE ROOF

326

BASAMENT WALL

foundation socket

ELEVATION WALL

stone wall earthen brick wall

ROOF

carpentry deck roof coverings

OPENINGS

openings: trilithic system doors and windows (frames) ventilation holes

EXTERNAL FINISHES

intermediate coat finishing coat limewash

INTERNAL FINISHES

floor internal plaster and painting decorations niches fixed furnitures

Fig. 10: Building processes.

Fig. 11a: Basement wall: foundation and socket. Fig. 11b: Basement wall: foundation and socket.

The elevation wall The stone walls Despite the variables that can affect the quality of walls, we may identify some common features, characterizing a shared heritage of empirical knowledge in construction. The walls can be classified into three basic types, in relation to the quality of local stone (limestone or basalt), to the degree of stone dressing and to the arrangement (Fig. 13). The stone walls are usually protected by an earthen plaster, often finished with a coat of limewash. The Double wall is built with the locally available stone (basalt, limestone, or mixed) with earthen mortar, stabilized with small stones used as wedges.

Fig. 12a: Basement wall: socket without foundation. Fig. 12b: Basement wall: socket without foundation.

327

Earthen Domes and Habitats

the foundation wall a stone wall of variable height is built, upon which the earthen masonry wall will be placed. The elevation wall is interrupted for openings, niches and the arch linking two cells. The wall is built in horizontal layers, with particular attention to the connection between the walls; at a variable height before starting the pendentive the arch is built, which will support the bricks of the former (Fig.10). The basement wall The base of the dome is a stone and mud wall, dug into the ground until the depth of a solid layer: the buried part of the wall is the foundation, normally with the same thickness (65-80 cm) of the supported wall, while the part above ground level is a socket to protect the building from erosion by rain water and soil dampness (Figs. 11a-11b). The foundation The foundation is built with irregular rough stones, placed as with a dry-stone wall. The excavation is filled with stones of varying sizes, making sure the gaps (or interstices) are filled between the bigger stones with smaller stones and mud (earthen mortar). The socket The socket is the part above ground level of the foundation wall. It is usually

built with large stones, often selected of similar size in order to realize constant height layers and create horizontal laying planes. In the areas where stones are not abundant (Oum Aamoud Kebir, etc.) the socket rests directly upon the soil, without the underlying foundation (Figs. 12a-12b). In these cases a preliminary layer of very large stones is built, between the soil and the brick wall, to protect the earthen wall as much as possible from water or soil dampness. When the stone shape is too irregular, the voids between are filled with an earthen mortar mixed with stones to create a horizontal plane on which to set the elevation wall. Finishes The interface between socket and ground is protected from water by a thick layer of clay over which is applied a layer of earthen plaster.

Basalt stone 328

Earthen Domes and Habitats

Opus Incertums wall with irregular stones

Double wall with regular stones layers

Double wall with squared regular stones

Limestone

329

Earthen Domes and Habitats

The appearance of the wall without a plaster protection can be particularly pleasing aesthetically with its variety of textures and colours (the colour of basalt, for example, is affected by continual oxidation), and also by the presence of small elements of different colours. The surfaces of split stones can be smooth and dark, and when oxidized become reddish and more porous (Fig. 15). The stone walls are always composed of two external vertical layers, not connected by orthogonal stone elements, the space between filled by a mixture of earthen mortar and small or medium sized stones, in a double wall technique (Figs. 14-18). The two stone vertical layers characterize the wall as they are executed as: - opus incertum, - regular layers and horizontal laying planes. The second, which is far more frequent, involves a selection of the kind and size of stone before the construction and the creation of stone rows of the same height; staggering of the vertical joints is not always respected. The stone of the double wall is usually slightly larger than the overhanging earthen brick (adobe) wall, the thickness thus depends on the type of dome: in the Sultan, or Sultanya, dome normally the ‘three header brick’ wall is supported by a 65-75 cm thick wall, while in transition dome the thickness may exceed 80 cm. The mortar is made with earth (clay and sand) and sometimes straw. Double wall or ‘opus incertum’ wall with irregular basalt stones The basalt stones are often round in shape, and very variable in size (Fig. 13a). An earthen mortar and several stone wedges are used, with a small amount of mortar in relation to the stones. This kind of wall is diffused in basalt stones areas, i.e. it is prevalent in Oum Aamoud Kebir, Oum Aamoud Seghir, Er Raheb, Fejdane, while in Rasm Hamd and Rbaiaa coexists with transition dome. Most of time it is associated with Sultan domes or transition domes. Double wall or ‘opus incertum’ wall with irregular limestone The limestone is slab shape or scale shape, often with sharp edges (Fig. 13b). An earthen mortar and several stone wedges are used, with a small amount of mortar in relation to the stones. This kind of wall is diffused in limestone areas, i.e. in Tayara, Rasm Al Bughere, Cheikh Hilal. Double wall with regular basalt stones layers The basalt stones are often round in shape, and very variable size. The stones are selected to form regular height layers and ensure horizontal laying planes (Fig. 13c).

7 3 7

4 3

3 4

1 foundation 2 socket 3 vertical layer

4 mixture of earthen mortar and small or medium sized stones

5 wedge 6 base coat 7 finishing coat

Fig. 14: Double wall.

Fig. 15: Oxidation of basalt stone. Fig. 16: Double wall: filling of earthen mortar and stones.

Fig. 17: Corner of basalt wall. Fig. 18: Corner of limestone wall.

330

Earthen Domes and Habitats

Fig. 20b: Corner deformation of three-headers adobe wall in â&#x20AC;&#x153;Sultan domeâ&#x20AC;? area.

Fig. 19: Stone wall and earthen brick wall.

Fig. 21b: Three headers wall.

Fig. 20a: Corner of three-headers adobe wall. Fig. 21a: Three headers wall.

An earthen mortar and several stone wedges are used, with a lesser amount of mortar in relation to the stones. This kind of wall is diffused in basalt stones areas. Most of the time it is associated with Sultan domes or transition domes. Double wall with regular limestone The scale shape stones are often placed inclined or otherwise placed in rows of uniform size, with horizontal or sub-horizontal laying beds, as in the previous type (Fig. 13d). The stones are tilted with abundant use of mortar to create a horizontal laying plane for the next row, the elements of which are inclined in the opposite direction. This kind of wall is diffused in Rasm Al Bughere, Cheikh Hilal. Double wall with squared regular limestone or basalt stones In this kind of wall the stones are squared, all very well worked: the stones come from the ruins of Byzantine period villages, we can also find old decorative elements like capitals, parts of columns, etc. The squared stones are used for the external layers of the wall, while the internal part is made with an earthen concrete with less regular stones, stabilized by the use of wedges. This kind of wall is diffused in the villages built on Byzantine ruins Rasm Hamd and Rbaiaa (basalt) (Fig. 13e) and Tayara (limestone) (Fig. 13f). The earthen brick wall The earthen brick (adobe) wall, is an elevation wall built on the base, a characteristic of the Sultan dome houses (Fig. 19). The wall is usually three-headers, sometimes four, thick.2 The two heads wall thickness is found only in the case of small and light domes or of flat-roofed buildings. This kind of wall is part of the building system of Sultan dome houses. The size of the brick varies from village to village, having regular proportions between the three dimensions of the brick, and in particular the approximate The way in which bricks are laid also has its own terminology. A brick laid so that one of its longest sides is visible in the finished wall is known as a stretcher. If it is laid so that one of the ends shows, it becomes a header. All bricks are laid to a specified arrangement to ensure maximum strength, load bearing property and a uniform appearance. This arrangement is called a bond. As a general rule, no brick should be laid directly on top of another: instead, it should overlap the joints between the bricks above and below it so that there are no straight joints running up the wall. The various bonding patterns in use all follow this rule and ensure that the vertical joints between bricks are staggered. In bricklaying, bricks cut to different sizes are all given different names. Cut in half across its width, a brick becomes a half bat. Cut to three quarters of its length, it becomes a three quarter bat and to a quarter of its length, a quarter bat. A brick cut in half along its length is known as a queen closer. This is used for building strengthened corners, or quoins.

331

Earthen Domes and Habitats

Fig. 22: Pendentive in adobe.

Fig. 23: Pendentive with wooden shelf.

ratio of 1:2 between width and length of the brick: the average size is 20 x 40 x 10 cm. The bricks of the older buildings are 20 x 50 x 10 cm: this ratio of 1:2.5 between width and length of the brick created technical difficulties in the building of a three-headed wall, particularly in the construction of the corner (Figs. 20a-20b). The horizontal and vertical joints, which have variable thickness, when skilfully done, are made with sieved earth mortar, often mixed with straw. The wall is often more thick than three heads (3 bricks of 20 cm plus 2-4 cm of earthen mortar vertical joints), because the thickness of vertical joints may vary to 5-6 cm. In this way the mason can adapt the thickness of the wall by modulating the thickness of the vertical joints according specific technical needs. The realization of a ‘three headers’ wall is regularly accomplished by alternating the brick layers and avoiding the alignment of vertical joints. For the realization of the corners the use of a sub-module of the standard brick: a quarter bat, 10 x 10 x 20 cm or a three quarter bat 10 x 20 x 30 cm, is obviously necessary (Figs. 20-21). village Oum Aamoud Kebir Oum Aamoud Seghir Rasm Hamd

Mazraat Al Rouihïeb

Rbaiaa Rasm al Bughere

wall brick size

dome brick size

38 x 19 x 9,5 cm 48 x 24 x 8/9 cm 40/42 x 20/22 x 8 cm 45 x 22 x 8/9 cm 47,5 x 22,5 x 9 cm 50 x 25 x 10 cm

45 x 22 x 4/5 cm 28 x 22 x 6 cm 31 x 18 x 6 cm 33 x 19 x 6,5 cm

40 x 20 x 10 cm 50 x 25 x 10 cm 40 x 20 x 12 cm

40 x 20 x 5/6 cm 50 x 25 x 5/6 cm 30 x 17 x 6 cm 33 x 17 x 7/8 cm

44 x 22 x 5 cm 19/20 x 10/12 cm

Fig. 24: Pendentive with stone shelf. Joub Maadi Cheik Hilal Sourj Meksar Shamlei

39 x 20 x 10 cm 47,5 x 22,5 x 9 cm

40 x 20 x 8 cm

40 x 20/21 x 8/9 cm 39 x 19 x 10 cm

The pendentive By ‘pendentive’ we indicate the set of building parts realized to achieve the transition from the square base wall or elevation wall to the circular, more or less regular, base of the dome, or in other words the three-dimensional element connection between orthogonal walls and the dome: the rows of bricks gradually take the shape of the internal perimeter from a square to a circle (Fig. 22). The use as a shelf of a piece of wood or a stone in the corner allows a greater overhang, facilitating the creation (i.e. less then 12/15 rows) of a circular base for the first brick layer of the dome (Figs. 23-24). The height of the starting point of the pendentive varies from 20 cm above the floor (normal dome), up to 1.5 meters (more common) or more (Sultan dome). This pendentive is a part of all kinds of dome, with dimensional variations due to geometry, but without changes from a technical point of view. The pendentive can be realized either with wall bricks or dome bricks, which are usually adapted, for example, by cutting the edges in order to get a trapezoidal shape and to reduce the void resulting from radial disposition and increase the surface contact between the bricks. The horizontal and vertical joints, which have variable thickness, when skilfully made, are made with sieved earth mortar, often mixed with straw. During the construction of the vertical walls, the muallem begins deciding the height of the shelf as the starting point of the pendentive. To get the transition from square to circle, step by step, or better brick layer by brick

NORMAL DOME

332

Earthen Domes and Habitats

7 9 6 Fig. 25b: Door of normal dome.

Fig. 25a: Vertical section view of a normal dome. 1 2 3 4 5 6 7 8 9 10 11 12 13

stone basament platform layers of â&#x20AC;&#x153;headerâ&#x20AC;? bricks door with wooden lintel earthen bricks post corbelled dome tantour standing stone (known as tantour) base coat finishing coat pendentive internal plaster (earthen plaster or lime and straw) decorations floor: layer of earth and straw

12 11 8 3

13 1

SULTAN DOME

333

Earthen Domes and Habitats

8 6 7

Fig. 26b: Start of corbelled dome.

Fig. 26a: Vertical section view of a Sultan dome. 1 2 3 4 5 6 7 8 9 10 11 12 13 14

stone basament wall elevation wall (wall brick) door with wooden lintel deformation of three-headers adobe wall corbelled dome (dome brick) tantour â&#x20AC;&#x153;two girlsâ&#x20AC;? standing stone (known as tantour) base coat finishing coat pendentive earthen brick arch floor: layer of earth and straw floor: bed of rocks and earthen mortar

9 4 11

10 3

13 14

334

Earthen Domes and Habitats Fig. 29: Tantour: arrangement of bricks.

layer, he gradually makes a deformation of the perimeter, corbelling the wall, starting from the corners. Consequently, the plane surface of the four vertical walls is going to shrink, taking the form of an arc, because the pendentives tend to be joined in what is the circular base of the dome. In this way the transition is usually mild and gradual, operating only through the slight jutting of earthen bricks, which do not allow a large overhang. The geometry, dimension and realization process of the pendentive is different for each of the four architectural types identified. The pendentive of the Sultan dome The Sultan dome (Fig. 25a) overhang begins in the four corners with wood, stone or brick cutting the edge and giving the base for corbelling and the internal brick layer of the wall. Consequently, the thickness of the wall increases, starting from the corners, and the space that is created is filled with pieces of brick, stone and mortar.

Fig. 30a: Tantour arrangement with two bricks, known as ‘two girls’.

After 5-6 layers, the mason begins to rotate the internal bricks and in the internal part of the wall we may have a conflict between the bricks; consequently, the bricks are cut, reducing the quality of the wall at the corners. Like in the masonry below, the filling of the voids is solved case by case using whole bricks, parts or flakes, and abundant amounts of mortar. The walls and the connected pendentives Fig. 31: Standing stones. end at the point where the internal circular perimeter is achieved. In some cases, in the interface between the wall and the dome we may see a layer of bricks rotated by 45° as a decorative element.

The pendentive of the normal dome In the normal dome (Fig. 26) it is difficult to distinguish the wall from the dome: the dome wall starts at ground level and is made in seamless continuity by layers of ‘header’ bricks, only rarely reinforced in the lower part by an external wall. In this case, the dome has an elongated ogival profile, (the bee-hive profile) the pendentive, which starts very close to ground level, has a key role as part of the dome itself in achieving the transition from the square shape at ground level to the circular shape of the dome, which is located at 1.0-1.5 meters.

Fig. 30b: Tantour arrangement with four bricks.

Fig. 30c: Tantour arrangement in triangle.

TRANSITION DOME

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Earthen Domes and Habitats

7 5

8 6

Fig. 27: Qantara interior (transition dome).

4 Fig. 28: Vertical section view of a transition dome.

1 2 3 4 5 6 7 8 9 10 11

stone basament wall elevation wall (wall brick) corbelled dome (dome brick) protruding stone tantour â&#x20AC;&#x153;two girlsâ&#x20AC;? standing stone (known as tantour) base coat finishing coat pendentive stone slab used like shelf (pendentive integrated with the lintel) 12 stone arch 13 floor: layer of earth and straw 14 floor: bed of rocks and earthen mortar

3 12 10

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The pendentive of the transition dome In transition dome (Figs. 27-28), the dome rests on a stone socket of considerable thickness, which at the last row is provided with elements at 45Â°, upon which the pendentive is set. The stone masonry basement therefore does not curve. These elements are made of a stone slab or parallelepiped shape. The pendentive of the horizontal top dome In the horizontal top domes (Fig. 32) we may find pendentives made in similar fashion to the Sultan domes, but also pendentives supported directly by a stone masonry base, as in the previous type. The corbelled dome The corbelled dome is realized by laying the earthen bricks according to a continuous helicoidal spiral, tapered and often tilted towards the centre. The main shapes of Syrian earthen corbelled domes are: - parabolic; catenary; conical or, better, multi-conical; truncated. The laying of the bricks according to a spiral permits laying in continuity without interruption and completing the horizontal rings with brick fragments. The mason lays the bricks, perched on the ring of the dome, in an anti-clockwise direction to favour the use of his right hand. This allows the construction process to proceed more efficiently, without any scaffolding or need to adjust the bricks. In order to increase the ergonomics of the building operation the size of brick is slightly smaller, to reduce the total weight of the dome and the work of the mason and of his collaborators. Smaller bricks mean easier building, due to the small size and lighter weight, and permit greater control of the internal profile of the dome. The mortar is made with earth (clay and sand) and sometimes straw, as with the mortar of walls. The thickness of the mortar is considerable (2 cm) compared to the thickness of the brick (4-6 cm). In order to prepare the base of the spiral, the mason lays a bed of mortar with increasing thickness, as a base with the right inclination upon which to lay the bricks in spirals (Fig. 26b). The correct angle of the laying base is difficult to maintain during on-going work and numerous adjustments can be seen in the domes studied. The overhang of bricks in relation to the lower layer is obtained by hand and without instruments. This leads to a profile less like a parabola and closer to a cone, or several cones, with a progressive angle that anticipates the closure. In most cases the bricks are tilted a few degrees toward the centre of the dome. Obviously, the laying of bricks at the top of the dome is a heavier and more dangerous task for the mason. The bricks are then

arranged according to this simple building rule (an operational instruction) until the end of the dome, observing the continuous spiral pattern and the overhang of each ring of bricks. The radial arrangement of the bricks create wedge-shaped spaces in between, gradually increasing as the dome rises, which must be filled with mortar, pieces of bricks or small stones. On the top of the dome the laying beds are more sloped inwards due to the weight of the jutting bricks and the amount of mortar used for laying. The construction of the dome without scaffolding forces the builder to work in a hazardous and difficult position: the mason, balancing himself on the ring of bricks backs up as he lays the bricks. When the top of the dome is approached the working position becomes increasingly awkward and dangerous, the rhythm is slower even for the harder work of lifting bricks up to the working layer, until the point where the mason is forced to work from the outside, finding foothold on the protruding stones with arms outstretched to lay the bricks. The construction of the pendentive and of the dome is based on an accurate and continuous control of the jutting out bricks, laid without instruments and only by hands: the overhang is measured by finger bones (distal phalanx for the first rows, intermediate phalanx for the remaining rows), with an accuracy depending on the skill of the mason. The protruding stones, flat and long (sometimes replaced by wooden elements), are fixed in the dome wall to protrude in an appropriate measure to support the foot of the constructor. The distance between stones is apparently irregular, but functional as regards the work of the builder and those responsible for maintenance afterwards: the vertical and horizontal distances of the stone rings allows easy access to the dome. The protruding stones and the pinnacle are not only functional elements, but are a major characteristic of the aesthetics of the domes. The top of the dome The top of the dome is executed with great accuracy, both formal and functional, as this part is the most prone to degradation and the most architecturally expressive. The â&#x20AC;&#x2DC;tantourâ&#x20AC;&#x2122; The tantour is a sort a pinnacle fixed on top of the dome as a completion. It consists of two parts: the pinnacle itself and the bricks where the tantour is fixed. At the top of the dome when the arrangement of the bricks into a spiral becomes difficult, the mason lays bricks horizontally to close the void, adds

FLAT ROOF DOME

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Fig. 33: Flat roof: supporting layer in non-woven natural material.

Fig. 34: Flat roof: supporting layer in interwoven natural material.

Fig. 35a: A building detail of wall-beam node.

Fig. 35b: A building detail of wall-beam node.

Fig. 36: A building detail of bricks jutting.

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Fig. 32: Vertical section view of a horizontal flat roof.

1 foundation wall 2 layers of â&#x20AC;&#x153;headerâ&#x20AC;? bricks 3 wooden lintel with fan shape 4 corbelled dome 5 wooden structure 6 supporting layer in non-woven natural material 7 covering layers of earthen mortar 8 final layer of earthen mortar with dung or well-sieved clay 9 base coat 10 finishing coat 11 niches 12 internal earthen plaster 13 floor: layer of earth and straw 14 floor: bed of rocks and earthen mortar

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2 11 1

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Earthen Domes and Habitats Fig. 37: A building detail of wall-beam node.

Fig. 38a: Earthen brick arches.

layers of clay mortar and fixes in a standing stone, the tantour, at the top (Fig. 29). The stone is not a mere aesthetic or symbolic object, it primarily prevents the stagnation of water on top, channelling rain towards the inclined surface of the dome. The fixing of the stone at the top of the dome represents the final act of dome building, and is followed by the payment of the mason by the owner. The hole in the last ring is closed with bricks arranged in different ways, according to local traditions: - two bricks, known as the â&#x20AC;&#x2DC;two girlsâ&#x20AC;&#x2122; (Fig. 30a) - four bricks (Fig. 30b) - triangle (Fig. 30c) The arrangement of bricks becomes also an internal decorative element. Fig. 39: Lintel.

Fig. 38b: Small closed earthen brick arches.

On the first layer of bricks the mason lays another pair horizontally, then fixes the standing stone, the tantour (Fig. 31), into the masonry, held firmly by pieces of bricks and earthen mortar, emerging from the plastered surface of the dome to mark the top. The flat roof The dome with a flat roof (Figs. 32-37), probably introduced from the Kurdish area of Turkey, is particularly diffused in the Valley of the Euphrates, due to the availability of wooden elements of a sufficient length, avoiding the necessity of constructing the more complex part of the dome. The mason stops the completion of the dome at a height equal to about half of a complete dome and constructs a wooden floor, covers it with layers of earth shaped with a low slope to prevent the stagnation of rainwater. The top of the dome is still more susceptible to degradation, especially in the absence of proper maintenance: this kind of roof is the more affected by rainfall and other agents of deterioration, which eventually may cause them to fall. The flat roof consists of the following parts: - a simple wooden structure which consists in most cases of 5-6 rough and round joists, placed at regular distance. The wood is usually of a lower quality and size than required - supporting layer (Figs. 33-34) consisting of non-woven natural material (reeds, thorn twigs or other branches), or interwoven material (mattings) - covering clay layers of considerable thickness (multiple compacted layers) with a slightly lenticular surface to prevent stagnation of rainwater and to increase the impermeability of the cover - finishing clay plaster, in some cases finished with whitewash or limewater, to increase impermeability and protect from vegetation growth. Other than areas where they are common, flat roof domes can be found in

areas such as Kanassir or Cheik Hilal. They can be used also for the functional recovery of degraded domes.

Openings The houses with corbelled domes have only a few small doors and windows, mainly from need to protect against the external climate, strong sunlight or winds. The openings do not create difficulties in construction because of their reduced size: the width of the doors is usually 70-90 cm while the height is 170 cm. The mason applies the trilithic system using wood or stone lintels (including mixed) supported on brick or stone posts (Figs. 40-41). In areas where stones are abundant, corresponding to the Byzantine period settlements, masons normally use stone lintels (two or three for the thickness of the wall), made up of stones dressed to differing degrees. The stone lintel usually rests on the jamb stones, often large or very well dressed to facilitate good contact between the elements (Fig. 28; Fig. 46).

Earthen Domes and Habitats

Arches and lintels The linking between two contiguous domes consists of arches made of earthen bricks or stones or of wood or, more recently, iron lintels. Earthen brick arches Earthen bricks arches are not regular arches: the bricks are placed not in a radial way but parallel at an angle of 30-35 째 from the horizontal. The keystone may be made with stones or bricks, creating a sort of broken jack arch or flat arch (Fig. 38a). As with domes, a wooden centre is not used: the mason makes a supporting masonry centre, the bricks being later used for the construction of the dome. Sometimes the masonry centre is not removed and remains as a closure of the arch (Fig. 38b). Stone arches The arch is made of stones, often recovered from ruins or poorly dressed, but always arranged in a regular radial manner (Figs. 27-28). Lintels In the Sultan domes, the opening between two rooms to seat the arch can be achieved also by a lintel composed of two wooden or steel beams resting on a wooden sleeper (Fig.39). The lintel allows a more effective connection between the two rooms, because it can be supported directly on the wall without the need for piers. This solution has been introduced in recent times due to increased availability of wooden or steel beams.

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Fig. 40a: Small window. Fig. 40b: Wooden frames.

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Earthen Domes and Habitats Fig. 41a: Rustic door.

Fig. 41b: Simple wooden frame.

In many cases, the lintel is wooden (Figs. 42-43), or rather made up of several rough and rounded wooden joists (diameter 5-8 cm). When the door is near a corner of the room, the lintel has to be integrated with the pendentive and assumes a fan shape to support the bricks of that feature (Figs. 44-46). Openings of normal domes In normal domed houses, the door must be opened in the dome: as the wall of the dome already starts to bend, the lintel needs to integrate two additional building elements, a sort of â&#x20AC;&#x2DC;door-postâ&#x20AC;&#x2122; protruding from the dome wall so that the door can be placed on a vertical plane. In these cases, the posts support the lintels and are made of earthen bricks clamped to the dome wall upon which the wooden lintel is supported (Figs. 25a-b). Windows and doors Windows and doors are affected by scarce resources of wood and wood crafts. Simple wooden frames Traditional frames are very simple, in most cases rudimentary: the doors are usually rustic with one or two parts, consisting of vertical boards and horizontal traverses, generally roughly worked and joined with iron nails (Figs. 43-44). The shutter is, in the cases observed, linked to a vertical pole that works as a hinge, by direct nailing or through nailed leather straps; the hinge pole sinks into a hole in the floor, while the upper part is placed in a hole between the lintel joists (Fig. 44). In this way the hinge maintains the vertical position and rotates to fulfil its proper function. We observed only a few cases of door

Fig. 41c: Door closed with mud mortar.

Fig. 41d: Metal Frame.

Fig. 42: Opening with wooden lintel on brick posts (door frames). Fig. 43a: Hole between the lintel joists.

Fig. 43b: Detail of lintel and wooden frame.

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Earthen Domes and Habitats

Fig. 45a: External view of the door.

Fig. 45b-c: Lintel with fan shape.

frames (Fig. 42), made of squared wooden elements (uprights and crossbar) of about 8 cm. The uprights are fixed in the wall using wooden connectors and the shutter is hinged with metal fittings purchased in nearby towns. The doors are often painted with bright colours, usually blue or green and decorated with iron elements. Metal frames For some years, more secure and simpler metal frames with one or two shutters have been replacing wooden doors (Fig. 41d). Closing systems The locking of the houses is always positioned outside (Figs. 47a-c), as these houses are inhabited by semi-nomadic peoples, and not used during dry spells. Therefore, in addition to rudimentary mechanical wood closing systems, the inhabitants close their houses, especially the domes for storage of grain or salt, sealing with an earthen and/or stone wall (Fig. 41c). Ventilation holes Ventilation is ensured by a series of ventilation holes, placed in strategic positions depending on climatic conditions and on internal function. The ventilation holes, mainly east/west oriented, are cut into the wall at varying heights: those located at the bottom of the wall (Figs. 48a-c) intercept the fresh air for a person sitting or lying on the floor, while those made in the dome allow hot air to escape (Fig. 49). The ventilation holes during cold season are plugged with stones and mud mortar or simply with rags. In domes with ovens the ventilation system must ensure the draw off of smoke as a form of chimney. The holes in the socket wall are not difficult to make: the lintel of the holes is

Fig. 45d: Lintel with fan shape. Fig. 46a: Stone lintel with fan shape.

Fig. 46b: Stone lintel with fan shape.

Fig. 44: Door with wooden lintel integrated with pendentive on brick jambs (rustic door with vertical pole). Figs. 47a-b-c: Closing systems.

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Earthen Domes and Habitats

simply an earthen brick or a stone while the holes in the dome were obtained by placing two bricks tilted against one another, creating a triangular shape. External finishes The external finishes (Figs. 50-53) are measures to decorate and to preserve the earthen masonry from degradation by weather conditions, in particular rain. Maintenance of the external finishes is generally the task of the women Intermediate Coat or ‘base coats’ Thick layers of base coat are applied on the wall at the critical points of construction, where the stagnation of rain or rising damp can occur, for example, at the base of dome or of the wall. The thickness of the earthen plaster is increased in order to link the various parts of the structure, smoothly shaped and creating drainage for rainwater. The mortar is applied and pressed by hand for better adhesion, minimizing the porosity of the material and to achieve acceptable levels of waterproofing (Fig. 51). Finishing coat After a few days after the completion of the base coat, the whole building is rendered with a thick layer of finishing coat, to be maintained and renewed from year to year with thin layers of the same material (Fig. 52). Limewash When available, a limewash painting is applied for decorating and protecting, reflecting sunlight and absorbing less heat during the hot seasons. Internal finishes The maintenance of the interior is also a task for the women, from the floor to the internal finishing coat, from painting and decoration to animal hair carpets and straw matting. Floor The floor is traditionally made with a layer of earth and straw of about 5-8 cm on a bed of rocks and earthen mortar (Fig. 54). Due to wear it needs an annual maintenance, when the finishing coat of the floor is renewed, moistened and beaten. In the 1960s, cement began to replace clay as the base and finishing coat of the floor, as cement requires less maintenance. Also the lower part of the walls to a height of about 40 cm tends to be mistakenly coated with a cement plaster to protect the wall from wear. This unsound way of using cement is widespread and creates serious problems for the walls (see the chapter ‘Recommendations for technical conservation’).

Fig. 48a: Ventilation hole (at the bottom of wall). Fig. 48b: Ventilation hole closed with glass (or with plastic). Fig. 48c: Ventilation hole closed with metal mesh.

Fig. 49: Ventilation hole in the dome.

Internal plaster and painting The wall of the dome is usually finished with earthen plaster or lime and straw up to about 2/3 of the dome, the top is finished only with limewash painting applied by throwing it in buckets. Finishing is applied on the internal surfaces using a very liquid limewash. The white colour increases the brightness inside the dome, protects and disinfects the surfaces: normally only the residential domes including kitchens and ovens are finished with coating and painting on the domes, while those for storage and animals are left unfinished. Decorations The interior walls are often decorated by the women with floral or geometric drawings in relief, usually in connection with the openings and niches. The parts in relief are made with a mixture of clay and vegetal fibres used for modelling and shaping decorations and elements protruding from the wall up to 7-10 cm. Also the plaster coating of the dome is often decorated, creating simple decorative motifs.

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Fig. 50a: External finishes. Fig. 51: Layers of finishing coat.

Niches Residential units are characterized by numerous niches for storage. The shape and position of niches is variable: the larger niches are openings in the brick wall generally with wood or stone lintels, or occasionally with earthen bricks arches (Fig. 55), while the smaller are sometimes simply dug into the wall. Fixed furniture In some villages the domes are furnished by small accessories in earthen masonry, such as separation walls, seats, fireplaces, etc. Construction with flat roof or low-slope roof The flat roofs or low-slope roofs, so common in other regions of Syria, are limited in areas of earthen dome villages by the scarcity of wood, not locally produced and therefore very expensive considering transportation. For the same reason, this type of construction is now widespread in the villages near the Euphrates River. In some areas the two different traditions, the dome and the low-slope roof, coexist, while in other areas they seem to merge

Fig. 52: Layers of finishing coats (critical point wall-dome).

Fig. 53: Canal built in metal slab and stone.

into the flat roof dome; in all cases the building techniques are simple compared to the complexity of constructing a dome. The terrace or flat roof house is called a dhar (Fig. 56), while the low-slope roof house with two slopes is called a gaououch (Fig. 57).3 Both houses consist of an elevation wall, up to 50 cm thick, with a stone basement wall. At the height of the gutter the mason proceeds to construct gables on the shorter sides on which to rest the ridge beam or, in the case of a flat roof house, the mason builds up one of the two longer walls on which to rest the beams in order to give a slight slope for rainwater run-off. Once the wooden beams are in position, the mason places the supporting layer (matting) and then the clay layer. The materials for the layers depend upon availability in the area. Foundation wall The foundation wall is made of a stone foundation and socket, usually 3

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Earthen Domes and Habitats Fig. 54: Floor.

Fig. 55: Niche.

achieved in horizontal layers. The thickness of the foundation wall is about 45-50 cm. The building technique is the same as with the foundation system of earthen domes. Elevation wall The main elevation wall is an earthen brick wall with header bricks (Fig. 59). The walls are built at the same time, in horizontal bands consisting of 4-6 courses of bricks: first the mason builds the corners, overlapping the joints between the bricks above and below it so that there are no straight joints running up the wall, then he builds the central part of the wall. The mason lays the bricks standing on the wall, without the aid of scaffolding: he needs at least two helpers for moving the materials, the bricks and the mud mortar for horizontal joints. Flat Roof or Low-slope roof Carpentry The wooden structure is notable for its simplicity of design and by rough wooden beams and joists, irregular in shape and section. Single slope roof The single slope roof is usually only supported by joists (amoud or oumed4), placed at variable distances, between 25-50 cm, depending on diameter and load bearing capacity (Fig. 60a). The beams are not longer than 3.5 meters5, and in the case of a long rectangular room the joists rest on one or more

amoud (Daker 1984); oumed (Ghiyas 1984). the width of the rooms of simplest houses is no more than 2 meters since branches or crooked trunks are used, called gharab or çaf çaf (Daker 1984).

beams, called Jayez or Jisre6, at a distance of no more than three meters (Figs. 60b-61). Currently steel beams are used. Two slope roof The two slope roof is usually supported by an irregular rough ridge beam, called gatou (Fig. 62) (ridge beam, diameter 13-17 cm; joists, average diameter 10 cm; distances variable between 30-50 cm). If the length of the room requires it, the ridge beam is supported by one or more poles7 or by earthen brick pillars. The slope of the roof varies from region to region8, for example, in the area of the Euphrates River the slope is very slight, almost horizontal. The deck The deck is traditionally made with organic material. The traditional supporting layers are: - reeds or leafless branches, not woven or linked in any way, the 5-10 cm thickness achieving resistance. This mass of fibres, however, facilitates the fall of dust and attack by insects and parasites: a carpet or a matting between the joists is a remedy. The matting can be locally produced with straw or reeds or often imported (woven palm leaves) - interwoven natural materials (matting), tightened by small joists (section 3 cm) or by iron wire netting (current solution), to increase load-bearing (Figs. 64-66). - wooden planks simply laid on the beams, called takhet (Fig. 67). This kind of supporting layer is more common in the more affluent houses, but it is widely appreciated for its performance; as a cheaper alternative plywood or compressed paperboard isorel called locally mazonite is also used (Daker 1984) - mattress of dried leafless branches called m’arez, joined to a layer of coarse straw, called sfir, or thorn branches, more widespread in the area of the Euphrates River (Daker 1984), Currently we can see many different solutions: the traditional, determined by the on-site availability of organic materials (Figs. 68-70), and the new, determined by availability of industrial or recovered materials, especially sheet metal. Roof Coverings The roof coverings consist of several subsequent layers. The realization of earthen coatings is a delicate operation, requiring great care and an adequate thickness, of about 20-25 cm, since good waterproof-

7 8

Jayez (Daker 1984); Jisre (Ghiyas 1984). Daker 1984 Daker 1984

Fig. 56: Construction with single slope roof.

Fig. 57: Construction with double slope roof.

External and internal finishes See finishes of earthen dome houses. Openings Initially the openings, the entry door, the windows and ventilation holes, were 9

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ing must be achieved without the use of impermeable materials besides clay. Usually it consists of two layers of the same mortar (earth, water, straw) placed at different times, well beaten by hand to increase density, and covered with a final layer of earthen mortar mixed with dung, in order to increase waterproofing, or of well-sieved clay, recently replaced by cement.9 The need for better waterproofing encouraged the evolution of traditional techniques to the introduction of waterproof industrial materials, which reduce the frequency of maintenance operations: a plastic or metal sheet is inserted between the two layers of the earthen mortar (Figs. 71-72). The use of sheet metal gives the possibility of creating eaves: the sheet is held firmly by round stones placed on the wall, and is then covered by the earthen mortar, becoming in this way a kind of architecturally distinctive eave. During the 1970s, reinforced concrete spread, originally only in the richest houses and in the first sedentary villages. The reinforced concrete roof is supported by earthen or concrete block walls or by steel or reinforced concrete girders, making it possible to exceed 5 meters in width. Because of the poor thermal insulation offered by this material, the concrete slab, often 15-20 cm, is then further coated with a layer of earthen mortar (20-30 cm) to improve insulation.

Fig. 58: Constructions with double slope roof.

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Fig. 59: Wall with header bricks.

Earthen Domes and Habitats

similar to traditional houses, but in recent years the quantity and size of the openings is increasing.

Fig. 60a: Rectangular room: joists, known as Oumed (Daker 1975).

Fig. 61: Jisre on earthen brick pillar.

Fig. 60b: Long rectangular room: beam known as Jisre (Daker 1975). Fig. 62: Double slope roof supported by an irregular rough ridge beam (known as Gatou).

Small ‘cob’ buildings The court house is completed by several complementary architectural elements, such as fence walls, internal fence walls, ovens, mastaba and smaller domes. A very versatile technique, the ‘cob’, is adopted for all purposes because it allows major freedom to create shapes with plastic and functional results. The earthen mix is similar to that used to produce bricks: ‘cob’ building uses a simple and consistent mixture of clay subsoil, aggregate, straw, and water in order to be easily posed and modelled into shape by hand to create solid structural walls, built without shuttering or forms (Fig. 73). The wall is built in horizontal courses, with one course dried before placing the next one, to ensure the stability of the construction. It is usual to incorporate stones in the wall (Fig. 74). ‘Cob’ domes The ‘cob’ domes (dewar), generally circular, but sometimes squared with very rounded corners, are mainly used as shelter for small animals, or as a general stock room. The dimensions vary depending on use: the largest may have a diameter up to 2.5 m, a height equal or higher, depending on whether the profile of the dome is ogival or almost hemispherical (Figs. 75-79). Often there is an aggregation of smaller domes, set against the larger. The base of the structure is of large stones, thicker than the dome wall, placed on the ground: these serve as a foundation and provide a minimum moisture insulation from the soil. The dome is built of a mixture of earth and straw laid directly and shaped by hand. Usually stones or courses of stones of uniform size are incorporated, so as to create a row of about 10-15 cm in height, with a horizontal laying bed for the following row (Figs. 80a-b). The building process goes on up to a ring 60 cm high, waiting until the wall is dry (about a fortnight) before going on to make another.10 The superimposed rings, slightly jutting inward, gradually decrease to close the dome. The thickness of the wall appears constant up to one meter from the ground, then goes on reducing in thickness as the wall begins to jut inwards. Consequently the size of stone decreases: more rounded at the bottom, flatter towards the top. 10

Ghiyas 1984.

wooden structure iron wire netting supporting layer (matting) layers of earthen mortar plastic sheet final layer of earthen mortar with dung or well-sieved clay 7 small joist

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Fig. 64: Supporting layer tightened by small joists.

1 Fig. 63: A building detail construction with single slope roof.

Fig. 64b: Supporting layer tightened by small joists.

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2 1 Fig. 65b: Supporting layer tightened by iron wire netting.

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Fig. 65a: Supporting layer tightened by iron wire netting.

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13 Fig. 66: Kind of interwoven natural material.

1 stone basament wall 1 2 elevation wall 3 opening 4 wooden structure 5 small joists 6 supporting layer (matting) 7 layers of earthen mortar 8 plastic sheet 9 final layer of earthen mortar with dung or well-sieved clay 10 stones 11 base coat 12 finishing coat 13 canal

Fig. 67: Wooden planks, known as takhet.

Earthen Domes and Habitats

1 2 3 4 5 6

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Earthen Domes and Habitats Fig. 68: Construction with flat roof.

In villages where stones are scarce, people use a mixture of earth and straw laid directly in place, shaped by hand to form elements, convex on the upper side and concave on the bottom, ending with a laterally tilted cut, corresponding to the amount of earthen mix used in each case. The shape helps a better matching between the elements, furthermore the inclination which varies from row to row helps to create a unique texture of the wall: one row is constructed in a clockwise direction, the next anti-clockwise (Figs. 81a-81d). Openings When used as a stock or poultry room, the domes have openings for the passage of small animals (35-65 cm in width), and the lintels are small wooden boards (2x4 cm), or wooden joists (diameter 3-4 cm). The dimensions are so reduced as to not to endanger stability. When the opening is higher, a protruding wooden and earthen frame is built. The openings are west oriented for better airing and to reduce the entry of insects.11 11

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Fig. 69: Building detail of wall-joists node.

Fig. 70: Traditional eaves.

Finishes The dome is externally coated with a mixture of earth and straw. Even small domes have flat stones protruding from the profile of the dome, used for construction and maintenance: the first stones for maintenance are placed one meter from the ground level, for easy access to the dome. If the dome is high, there are more rows of protruding stones (at least two rows): the highest row is always complete while the lower only serves to climb to the next row. Fence walls of the court The enclosure walls (Fig. 82) of the court are often made with the â&#x20AC;&#x2DC;cobâ&#x20AC;&#x2122; technique, but with larger stones. The stones are not carefully placed, but they are selected for their dimension to taper the wall. On top of the fence wall, flat stones are arranged, tilted and held firm by wedges. The wall is then plastered with earthen mortar. Fig. 71: Eaves with metal slab.

Fig. 72: Roof coverings, with metal slab and plastic.

Fig. 76: Small dome with doorpost. Fig. 77: Stock dome closed with mud mortar. Fig. 78: Small domes integrated with enclosure walls of the court. Fig. 79: Squared cob building.

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Earthen Domes and Habitats

Fig. 73: Cob technique. Fig. 74: Cob technique: stone incorporated in the wall. Fig. 75: Small cob domes.

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All the internal fence walls of the court are built in the same way: if intended to fence in animals, they are finished with a number of shrub branches placed vertically on top of the wall to prevent the passage of animals (Fig. 83).

Fig. 80 b: Dome built in cob with stones.

Oven and mastaba Ovens, and walls built to protect them from the wind (Figs. 84-85), are made with earth by hand, even the terrace or mastaba, a kind of raised platform, is made with stones of different sizes to be filled and plastered with earthen mortar (Fig. 86). List of References Aurenche, O. 1981, La maison orientale. L’architecture du Proche Orient Ancien des origins au mileu du Quatrième Millénaire, Librairie Orientaliste Paul Geuthner S.A., Paris. Besenval, R. 1984, Technologie de la vôute dans l’Orient ancienne, Synthèse n° 15, Ed. Recherche sur les civilisations, Paris. Daker, N. 1984, ‘Contribution a l’étude de l’evolution de l’habitat bédouin en Syrie’, Aurenche, O., Nomades et sedentaires. Perspectives ethnoarchéologiques, Ed. Recherche sur les Civilisations, Paris. Ghiyas, Al. 1984, L’architecture traditionnelle en Syrie, Etablissements Humains et environnement socio-culturel, UNESCO. Meda-Corpus 2004, Traditional Mediterranean Architecture, école d’Avignon, Avignon. Terra Incognita. Discovering and Preserving european earthen architecture, 2008, Ed. Argomentum/Culture Lab Editions, Lisbon/Brussels Fig. 80 a: Dome built in cob with stones.

Fig. 81a-b-c-d: Dome built in cob. Fig. 82: Enclosure wall.

Fig. 86: Mastaba.

Fig. 83: Internal fence wall finished with branches.

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The constructions made of raw earth that typify the villages on the outskirts of Aleppo represent a typology of settlement which, over the centuries, has shown particular effectiveness and sustainability. In a context where wood is almost entirely lacking, the system of roofing which is peculiar to these structures bears witness to a complex and architecturally demanding building process. We all know how the building of a domed structure without supporting devices (ribs) demands a building process contemplating self-support, and thus has arisen, since antiquity, an ‘easy’ procedure of brick laying by successively jutting horizontal rings in a progression that culminates with the blocking out of the light at the top. This is the reason why the final outline of the building more closely resembles a cone rather than a ‘classical’ dome or a hemisphere, which would not work. In this building process, therefore, the shape is conditioned by the need for stable rings. In a more general context, illustrated by the widespread diffusion of such building methods in several Mediterranean regions, Syrian domes represent a true peculiarity. In the context of beehive building of raw earth, so widespread across North Africa and the Near East (Besenval 1984), this solution stands out with almost horizontal laying beds and particularly thin sections. This case raises questions about many interpretations regarding the structural functioning of beehive buildings (pseudo-domes) which are otherwise valid as far as stone block or flake constructions are concerned: the latter, in fact, require much thicker sections in order to balance, with the outer load, the laying beds whose natural tendency is to fall inward (Benvenuto 1988; Mainstone 2001). In the case of Syrian domes, the chosen building method, the materials employed and the particularly thin sections, demand a particularly complex analysis. The survey is therefore aimed at the description of the geometric characteristics, of the walls, and of the building method in order to discover specific critical issues and highlight the structural logic of such buildings.

University of Florence, Italy

This is an obligatory method for putting forward an analysis of the mechanics aimed at assessing the stability of these particular artefacts, both during construction and in their daily use (Fig. 1). Building techniques and materials Within the methods of analysis aimed at understanding structural behaviour, a key role is played by the identification of the building solutions/rules adopted. Dialogues with master builders met in the villages, as said above, (and regarding concealed issues on technological choices) have been very useful for gathering information on building processes. Methods of construction have, within such social contexts, limited variants, they are rather the outcome of a few shared rules based on the codification of a process of self-construction. Housing designs are largely repetitive: the basic dwelling consists of a quadrangular box, with substantial walls and a variable height (from 1 to 3 meters). In the system of aggregation of individual cells, whose dimensions vary little, as we have observed above, the internal connecting element consists

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Constructive and structural analysis: identification of the structure

Mirta Paglini Luisa Rovero Ugo Tonietti

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Fig. 1: Section Sultan dome

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of an arched doorway of considerable bearing capacity (Fig. 1). The dome, pseudo-conic, entirely made of jutting sun-dried bricks, rests elegantly upon the above-mentioned box. The typology referred to is by far the most common, albeit accompanied by several variants. Among these the most archaic is represented by the ‘simple dome’, a construction whose cone-like structure almost reaches the ground without real interruption, thus without the ‘break’ between the dome and the outer walls: intermediate solutions, however, are many and there are dwellings with proper vertical walls where roof and wall connect in a variety of ways. From a structural point of view it is important to observe how even in the most ‘modern’ type of dwelling (the Sultan, or Fig. 2a-b-c: Earth extraction and brick making

‘Sultanya’, dome set on vertical walls of large dimensions), we find solutions in the connections (or in the ‘pendentive’ and in the mesh of the upper part of the walls) that recall, self-consciously to different degrees and to differing degrees of effectiveness, the continual cone-like archetype (simple dome) even from a structural stand point. A careful observation of the joining devices is therefore the crucial issue for a full assessment of the mechanics. It is important to emphasize how the choice of materials always takes place near the village, in clay soils (bricks contain three parts earth to one part straw and water). The components are the outcome of a similar selection which applies both to bricks and to mortars. The sieving process through which the mix of the mortar is obtained, insures a higher cohesion to the clay and consequently a higher degree of adhesiveness. The accompaniment of two substances similar in composition and brought to work together is, as we shall see, crucial for the assessment of the structural behaviour of the whole (Figs. 2a-c). Walls and foundations The foundations for this type of structure are rather coarse, made of large unfashioned stones sunk into a mix of earth, but they generally are as wide as the wall they support. Right above the foundation is a plinth made of rough stones mixed with abundant earth (60 to 70 cm thick). The character of such stone plinths vary according to the availability of local stone, to its quality (basalt, white stone), dimensions of elements and type of work. It is apparent that the state of this element depends largely on the ‘cohesion’ of the mix of which the base cell is made. Water percolation or loss of part of the earth fill suffices to cause serious subsidence (Figs. 3a-b). Upon this plinth rests the box of the base cell. The wall is made of sun-dried bricks and plaster of raw earth of varying thickness. We find walls with three and also four heads, occasionally with a two head texture. As already said in section 3, the toothing defects on the corners are blatant since the possibil-

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Fig. 3a-b: The wall base

Fig. 5a-b: The brickwork

ity of superimposing blocks is limited to ¼ of a brick. The use of one texture rather than another is never casual, to the use of a four head (ends) texture (Figs. 4-5a-b). Arch and pendentive In the frequent case of double cell buildings (there are also rare cases of three cells), the connecting element is an arch (Fig. 6). This is a control element in the delicate constructive transition between the elevation walls of the box and the point of support of the dome; this is built together with the perimeter walls and without support ribs. One possible means is the development of a wall that is removed upon completion of the second cell (which may occur even after some years). In most cases, the arch is made of sun-dried bricks and raw earth plastering (there are examples made of stone and raw earth mortar), with a mostly three head texture. Rarely do we observe effective toothing between the arch and the perimeter walls of the dwelling cell in which it is inserted (almost in breach). Texture is seldom truly radial, (it is so only in the more accurate of works) and for this reason it represents a weakness of the structure, subject to localized subsidence and scroll (Figs. 1-7). If the arch is in some way a control element, the ‘pendentive’ constitutes the true union between the box at the base and the dome above. In this case the passage is extremely delicate. In the realization of this element a crucial role is played by the relationship with the living space inside the cell. The case where expediency consists of leaning on a ‘special piece’ inserted

Fig. 4: Sketch of a ‘three ends’ brickwork

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into the wall is frequent, be this a sun-dried brick or, in some contexts, a wooden plank or a stone block. Notwithstanding that this choice is connected with a degree of fragility, it avoids a sudden variation of shape in the corner and a greater length of vertical wall (Fig. 8). A more complex solution, also occurring during the building phase, is to obtain the pendentive as the result of a progressive ‘deformation’ of the right angle in such a way as to avoid too sudden a passage between the square and the circle. In this case, the passage is gradual and consists of the separation of the wall into two individual entities: on the outside a thin ‘skin’ is maintained at a level with the walls, whereas on the inside a surface is created by deformation, a surface close in shape to the sector of a sphere. In this case we are confronted with an intermediate typology between a geometric Sultan dome type and the ‘simple dome’ type (Fig. 9). The dome The horizontal laying bed dome, made of superimposed progressively jutting rings, is created with sun-dried bricks and raw earth mortar. A preliminary comment must undoubtedly be made in consideration of the dimensions of the bricks used in the construction. In this case thinner bricks are used (around 5-6 cm) as compared to the bricks used in the base (Figs. 10a-b). Such a choice stimulates various considerations, both of a geometric-constructive and of a formal nature. The use of a thinner brick enables first of all a better control of the curve being produced by controlling the extent of the juts and, in addition, as the work goes on it insures the achievement of a shape with a pleasant aesthetic character. Furthermore, we may observe that the bricks used in the construction of the dome are more accurately made compared to the bricks of the wall. This extra care, evident in many artefacts, finds its motivations in the complexity of the building system where precision gives a greater evenness in Fig. 7: The arch

brick laying and thus an easier working process. One must also remember that the circular surface where bricks are laid is not perfectly horizontal, but endowed with continuity through laying bricks in a spiral progression. This means that at the end of each ring one finds oneself at a higher level (than at the starting point), equal to the thickness of one brick. The tilt is therefore very small in the lower rings (growing as the work progresses) but adheres to the rule of a progressive jut (Fig. 11). A device of this nature, remarkable in terms of geometric construction, does not alter a hypothesis regarding the structural behaviour in the context of the so-called ‘false’ domes, even when it agrees with the idea of an apparatus-system with a vocation for cohesion. This operation, by jutting blocks, makes the process self-supporting. It appears evident, however, that the rings must be made with care and each one must possess a certain firmness (at all possible levels) and insure a solid base for the ring that follows. In the case under survey, the material and the expedients adopted (fillings of earth and discarded material between one brick and the next) undoubtedly contribute to the firmness both of the parts of an individual ring and of the other rings that make up the whole. This means that once the structure is complete, and during the process of building, it comes close to a kind of conglomerate and this affects its structural behaviour. Such building process also shows its complexity, especially in the terminal part of the building. In fact, the jutting increases as work progresses towards the summit of the dome. The study of sections enables the observation of a certain regularity in the design of curves, with constant symmetrical relationships between plan dimensions, wall thickness, and height of the roofing. It is interesting to note that whilst confronted as we are by generally uneven and unique solutions, we also observe, at the same time, the repetition of an underlying widespread and almost consistent form. It is, in fact, a matter of rotating solids with a

Figs. 8-9: The different Sultan dome pendentive solution

Fig. 10: Different brick dimensions in the dome and in the wall

Fig. 11: The ‘spiral’ dome device and the final ‘weak’ conclusion 357 Earthen Domes and Habitats

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substantially parabolic matrix or, if you like, circular, centred off the symmetrical axis and off the base plan, with an ogival profile. Thicknesses are rigorously dictated by the dimensions of the bricks, by their jut and by the layer of earth superimposed as a means of protection in growing quantity as one approaches the impost (Fig. 12). Identification of the structure The unquestionable originality of the above described artefacts, the product of knowledge imbedded into the cultural context, obliges us to continue our quest with an attempt to clarify two fundamental points. On the one hand, there is the need to comprehend the structural mechanism, and on the other, directly related to the first, to proceed in the assessment of building faults, shown by blatant or presumed weaknesses. A possible first interpretation of the performance of such original devices is based on a sort of “indirect” test. We cannot, in fact, think of assigning the Syrian dome to the typology of “false domes” for which a strong external charge is necessary for insuring stability. In the most rigorous of hypotheses, which restricts the necessary condition of balance to the balance of the single block, our domes could not rise above the maximum height of one metre (Pizzetti & Zorgno Trisciuoglio 1980). Such a hypothesis is in fact based upon an assessment of stability based on the balance in upturning a small portion, or a thin slice, of the dome. We speak, in this case, of a ‘plane model’ since we imagine that a contribution to balance is only given by the examined portion without demanding cooperation from the construction device taken in its spatial integrity. In other words, we imagine that there are no contributions of a static nature connected to the close ring shape of the structure, but that it all boils down to the functioning of a similar system to that of an arch with jutting blocks. Such model, as we perceive through simple considerations of a static nature, induces the structure to assume a nearly conical section with a near vertical slope and, at the same time, to accentuate the extension of the part of the blocks (or of the tiers) which plays a ‘stabilizing’ role, or which is in ‘estrados’ with respect to the vertical line starting from the first block on ground level. This should easily explain why most buildings with jutting blocks show very thick sections, with considerable balancing components, often obtained with compressed earth (underground constructions). On the contrary, as mentioned above, we are confronted with quite slender soaring domes. The system could not stand up, as we have seen, if not by virtue of a ‘spatial’ cooperation, which brings forward a different interpretaFig. 12: Brickwork and the recurrent shape of the domes

Building criticalities As far as the second point is concerned, or the assessment of criticalities, the analysis of the building technique highlights some weak points in the system; on closer examination the recurrent cracks and the explicit crises (collapses and ruins) enable us to draw some conclusions. The greater part of cracks concerned the corners of the base box wall; this is to be attributed not only to poor toothing between orthogonal walls, but also to the weight brought to bear upon the pendentive (Figs. 14-15). The first situation, depending on the difficulty of integrating two coinciding walls with a three head texture (which superimpose only with ‘quarter’ bricks), makes the ‘box’ fragile with respect to all possible different collapses, probaFig. 13: A ‘macro-element’ standing after a dome collapse

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tion of the structural device (Fig. 13). This cannot occur without creating a ‘unicum’ whose horizontal supports are set into a cohesive mass, a conglomerate created by a perfect compatibility between sun-dried brick and mud. In this case the material ‘earth’ appears crucial for obtaining the quality of a consistent whole, an achievement quite impossible in domes made of stone flakes or blocks. A hypothesis of this kind ‘holds’ if we show that the mechanical characteristics of the material, extremely weak in terms of consistency, are not undermined. A simple calculation will show how the average stress in compression, caused by its own weight, upon the base ring, measures about 0.3-0.4 kg/ cm2. We can see how such a stress is absolutely compatible for brick (or for a conglomerate of brick and mortar made of earth) even of poor quality (with a breaking point that may vary from 10-15 Kg/cm2) (Houben & Guillaud 1989, Rovero 2008). We must not forget however that the stress regime in domes suffers also from stimulations along the rings or along the parallels (Timoschenko 1959). And here it is interesting to observe that the existence (and the diffusion) of domes points to the fact that the shape must be in some way suited to granting the absence of significant stresses (in this case a possible traction) acting according to the parallels, being incompatible with the qualities of the material (values now very close to zero). A later survey, especially assigned, will enquire into this area, with the aim of highlighting the kind of stress of the static system outlined above described in order to obtain the necessary data. Finally, we must not forget how this interpretation has been confirmed by the originality of the method of construction (a spiral, which strengthens the inclination towards the continuity of the object), making the absence of supports during the building works plausible.

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Earthen Domes and Habitats Figs. 14-15: The wall corner weakness; Fig. 16: The base damage induced by displacements; Fig. 17: The weakness of the brickwork induced by the transition between the dome-ring and the squared-box. See consequent cracks

bly due to scarcity of cohesion of the plinths made of random laid stones and pebbles affected by damp, etc. (Fig. 16). The walls of the base square appear to be leaning against one another, thus not suited to preventing or contrasting movements of various nature. The second weakness derives directly from the way the structure of the transition from the square to the circle of the dome works. As mentioned above, the execution of the device shows difficulties and complexity of a geometric and constructive character, but most of all it causes great loads to come to bear upon it (we may extrapolate that about 1/8 of the domeâ&#x20AC;&#x2122;s weight bears upon the pendentive, this is no less than 2.5 tonnes). For these reasons, almost all possible crises bear upon the corners (from here they fan out to involve parts of the dome) (Figs. 17-19). This is especially true with reference to the constructive devices conceived as elements of the Sultan domes where a discontinuity between base box and roofing system is particularly evident. More elements of structural fault concern the condition of the inner arches, which are subject to loads double the weight of those bearing on perimeter

walls (two domes rest upon them) and for this reason they must rely on high quality textures and composition in the bricks, or risk subsidence of the key and rupture of the apparatus. The double cell building being so frequent, such problems are also common along with the demands for insuring solidity between the arch and the wall (Fig. 20). A last note concerns the delicate operation of â&#x20AC;&#x153;closingâ&#x20AC;? the dome; here the disposition of bricks, still in a spiral fashion, must follow ever increasingly narrower curves which tend to close with the narrowing of the spiral at the top (Figs. 11-21) As a consequence, builders resort to textures with an increased quantity of mortar and to increasingly more prominent juts; the builder must also use his utmost skill. In rushed works, small movements become inevitable and with them the risk of leaks increases: many crises begin with subsidence in this part of the structure. As stated above, the dome structure, when well made, is an excellent solution both in structure and function. Its intrinsic weakness is actually a reflection of the weakness of the material: earth, which becomes fragile when exposed to the action of snow (or worse, to winter deposits on the north side) or rain

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Figs. 18-19: The weakness of the brickwork induced by the transition between the dome-ring and the squared-box. See consequent cracks

(the design of the drainage system as a distinctive decorative element is very interesting), and is most of all vulnerable in a scarcity or absence of careful, regular maintenance. List of References Benvenuto, E. & Corradi, M. 1988, ‘La statica delle false volte’, Nel cinquantenario della Facoltà di Architettura di Napoli, Franco Jossa e la sua opera, Napoli. Besenval, R. 1984, Technologie de la voute dans l’Orient Ancien (2 vols.), Recherche sur le Civilisations, Paris,. Briccoli Bati, S, Rovero, L. & Tonietti, U. 2008, ‘Considerations on methods to evaluate the compressive strength of earth building materials’, International Conference ‘Terra 2008’, Bamako. Chadmi, H., Dipasquale, L., Mecca, S., Rovero, L. & Tonietti, U. 2007, ‘Technical knowledge and traditional architecture in Medina of Chefchaouen’, International Conference RIPAM 2, Marrakech Devaux, E. 2006, Les coupoles en terre en Syrie, Mémoire du Diplôme de Spécialisation et d’Approfondissement, Architecture de Terre, DSA–Terre, Ecole Nationale Supérieure de Grenoble. Houben, H. & Guillaud, H. 1989, Traité de construction en terre, CRAterre – EAG, Parentheses, Marseille. Mainstone, R. 2001, Development in structural form, Oxford Architectural Press. Pizzetti, G. & Zorgno Trisciuoglio, A.M. 1980, Principi statici e forme strutturali, UTET, Torino. Rohlfs, G. 1963, Primitive costruzioni a cupola in Europa, Leo S. Olschki, Firenze. Timoshenko S. 1959, Theory of plates and shells, McGraw-Hill Book Company.

Figs. 20-21: The weak joint between the arch and the wall

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What was highlighted in the previous section is the structural aim in the Aleppo corbelled course dome building technique, enabling an understanding of the specific hierarchy and the weaknesses of such constructions. In particular, it seems important to stress that the dome, as a distinct structural element, appears stable enough and compact. In consideration of this we can now proceed to some statical analysis founded on and related to these acquisitions. The direct survey of several domes enabled us to reconstruct, almost entirely, the geometry and building techniques of these roofings. In the dome, bricks are arranged lengthways (placed transversally in the brickwork) to establish the thickness, juxtaposed with each other, in slightly tilted layers to allow a spiral growth of the wall. This feature – difficult to capture but repeated in the examined cases – appears connected to the building process and combines well with the necessity of achieving an overhang (between overlapped bricks) varying from 3 to 6 centimetres (that can become greater in the concluding rings at the top). The vertical supporting walls show a greater width than the dome (in the ratio 3:2, then around 60 cm), and sometimes consist of more coarse bricks (thickness of around 10 cm). The most striking thing in the above structure is certainly the profile of the dome. This – since it is made of earthen (sun-dried) bricks and with these geometries – has such a slender appearance that certainly contradicts, as we just said, classical assumptions about the behaviour of ‘false’ domes. To summarize: these structures are usually ‘explained’ through the stabilizing role that the wide horizontal extension of the courses (from the opposite side of the overhang) assumes against the risk of upsetting the bricks. The consequence of such technique creates sections of great thickness. But here the thickness is not great and so the behaviour of the structure must be interpreted on different bases. The hypothesis from which we start is that a special structure could emerge during the process of construction, owing to the adherence between brick and mud mortar. Such a structure starts from a single

University of Florence, Italy

Fig. 1: Study case: house in the village of Alrahib, south-east of Aleppo

ashlar but gradually extends to the whole ring and then to the paraboloid. We do not know, in truth, how strong the bond is between bricks and mortar, but certainly a strong cohesion (involving rings or parts of them) is obtained. In fact, upsetting would otherwise occur in this geometric configuration when the building process reached the elevation of about one metre from the impost. Thus it seems right to interpret the global functioning of Syrian domes to the result of a constructive process that achieves something like a ‘conglomerate’ and entrusts to this, helped by its shape, the burden of stability. In order to investigate the plausibility of this hypothesis and the special conditions of geometry and strength by which stability is achieved (or declines), it was thought of simulating the stress and the stability of the system by checking its compatibility against the characteristics of the material. It is a well-known fact that the process of simulation of mechanical behaviour through virtual instruments (analytical or numerical) requires some conditions to be met, regarding the plausibility of the proposed model from a

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Statical analysis of the earthen corbelled course domes

Mirta Paglini Luisa Rovero Ugo Tonietti

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geometric, physical and mechanical point of view. Anchoring our choice to the requirement of a hypothetical ‘monolithic’ system, and to the undoubted ‘thinness’ of the dome profile, models referencing the membrane theory were considered suitable, both for analytical and approximate graphic solution. Besides, an FEM (Finite Elements Method) investigation was carried out in a linear elastic regime, with the adoption of shell elements. The analysis sought to comprehend ‘if’ and ‘what’ relationship might exist between the shape of the domes and their firmitas, what were the qualities in structural performance, what were the weaknesses of the building, and finally, how plausible was the adopted model in order to reproduce the construction process. As will become clear later, we will examine a real case representative of a large class of domes, valued as separate structural devices. This type of dome is referred to as the ‘Sultan dome’. Identification of a typical dome In order to perform the necessary analysis for an understanding of the structural behaviour of domes in sun-dried bricks that typify, with few significant variations, the region of Aleppo, we studied a house in the village of Er Raheb, placed near the salt lake of Jabboul, south-east of Aleppo (Fig. 1). The house consists of two square cells, flanked by a communicating arch, and both covered with a dome, according to the typical pattern in this whole area (Fig. 1). This unit has been chosen as a case study because it was representative of the type prevailing in the region, for its good state of preservation and its isolated condition (and therefore easier to be drawn). An initial approach, useful for understanding the structural behaviour of the domes, focused on the analysis of similar constructions characterized by a Fig. 2: Cross section of the dome: real section (left) and extrapolated section (right)

state of degradation (lack of plaster or partially collapsed). This investigation identified the size of the bricks (400 x 200 x 70 mm), the thickness of the joints (10 mm) and the type of texture (two brick ends). An analysis by sclerometer, through Building Material Test Hammer (Proceq), conducted on several walls, allowed the establishment of a reference value for the compression strength of the material which forms the dome (σ=1-1.5 MPa). The project researchers carried out a survey, through laser scanner, of the chosen housing cell. This survey provided cross sections and plans of the building (Fig. 2). The set of points – provided by the relief trough laser scanner and defining the intrados and extrados of the dome – were developed and, through an interpolation minimizing the deviation, special equations approximating the real curves were determined (Fig. 2). On the basis of these calculations the average curves (to which all the modelling, both analytical and graphical and numerical, are referred,) and the thickness (involved in the evaluation of the weight and in the definition of the numerical model) were determined. We tried to take some samples (of bricks and mortar) from the villages in order to carry out mechanical tests on earthen materials, but complex administrative reasons prevented them from being sent to the laboratory of the University of Florence. So, to carry out the structural analysis, the properties of earth materials – such as specific weight γ (which is involved in any modelling) and the elastic modulus E and the ratio of the Poisson ν (involved in the FEM analysis) – were assumed by referring to typical values (γ = 1600 kg/m3, E = 2800 MPa,ν =0.1) available in the literature (Briccoli Bati 2001; Briccoli Bati 2008; Houben 1989). The results of the three different analyses are shown in separate paragraphs below; while in the conclusions these results are compared and commented on. Structural analysis Closed form solution with membrane theory As a first approach to the study of the stress of thin domes, resulting from a revolution around the vertical axis of whatever curve, it is convenient to use the membrane theory. With this theory, the structure is free from bending and torsional stiffness and the stress belongs to the plane tangent of the middle surface. With this assumption the problem of determining the stress is an isostatical problem and the solvability is determined only with balance conditions. Then, when the external forces are only the weight of the dome itself, in addition to the geometric symmetry (created by the ‘revolution structure’), there is the loading symmetry, the stress becomes symmetrical, and the description

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is highly simplified. Every ‘slice’ of dome (a piece obtained with vertical planes passing through the axis) is subject to the same stress as all the others and every element of the dome, sited between a parallel and meridian, is subject only to axial forces, direct as meridians and parallels (shear forces are null because of geometric and loading symmetry). Thanks to these assumptions, it is possible to interpret the mechanical behaviour of the domes as a set of meridians able to convey upon themselves, as funicular arches, only that part of the load, which makes any meridian a ‘funicular arch’ of such load and parallels (subject to radial forces) able to guarantee the continuity between the meridians. The parallels carry the part of the load non-accepted by the meridians (Pizzetti 1980; Timoshenko 1959). If the curves, that create the dome by rotation about an axis lying in the plane of the curve, have a simple analytical expression, it is possible to determine the closed form expression of the stress functions. For the examined dome, it is convenient to consider the solution for domes generated by the rotation of the circle arch, where the centre does not belong to axis of symmetry, subject only to its own weight (Fig. 3). In these conditions, with the assumption of uniform thickness s, Nφ (the force, per unit thickness s, tangent to the meridians) and Nθ (force, per unit thickness s, tangent to parallel) are given by: Nφ=-γsR[(cosφo-cosφ)-(φ-φo) sinφo]/[(sinφ-sinφo) sinφ] Nθ =(γsR/sin2φ)[(φ-φo)sinφo-(cosφo -cosφ)+(sinφ-sinφo) cosφ sinφ] being γ the specific weight of volume, R the radius of arch circle, φo the angle that defines the arches key and φ the generic angle that identifies the location along the meridian (Fig.3). The evolution of stress along the meridians (Fig. 4) shows a progressive increase of the compression in the direction of the springs (up to the maximum value of 0.034 Mpa). As for the stress along the parallel (Fig. 4), a great similarity is evident with the static solution of conicalshaped domes: even in our case, there is never a sign reversal of the stress (that always remains a compressive stress). In other words, and for obvious reasons of form, all rings, at any height, are compressed, because they are subjected to centripetal radial actions. The values of the stress are very low, about equal to the summit and to the springs and with a maximum (0.011 MPa) at the height corresponding to half of the dome (Fig. 4). Quantity and quality of stress allow the exclusion of the occurrence of a possible crisis of strength: in particular, the absence of any tensile stress assures, from a mechanical point of view, the reliability of the analyzed dome. We must always remember that our systems are made with a simple material endowed with low strength: for example, even a trivial tensile force on the parallel would cause an irreparable crisis of the whole structure.

Fig. 3: Geometric model for closed form solution with membrane theory Fig. 4: Comparison between the results of the different analysis

Fig. 5: Graphic solution with membrane theory

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Graphic solution with membrane theory An interesting graphic solution, based on simple and intuitive conditions of balance, is available by accepting the assumption that the structure is replaced with a surface – the real middle surface – on which the whole resistant section is concentrated. The great versatility of this approach consists of the fact that it is enough to ‘draw’ the middle surface of the dome and then to consider the dome as a set of overlapping rings on which it is possible to impose the condition of balance (Fig. 5). The only permissible approximation is the linearization of the middle profile through many straight segments (a broken line instead of the real curve). The vectors polygon, representative of each ring balance, allows us to determine, through a simple relationship, the components of the internal forces along meridians and parallels. This method is characterized by immediacy, as all synthetic approaches, and it has the great advantage of making it possible to determine the stress in revolution thin domes generated by the rotation of any curve. In fact, in several cases it is difficult to describe analytically the irregular or complex revolution curves, which are a chief characteristic of many buildings and architecture. The laws of variation of stress inside the structure (Fig. 5) were extrapolated, by determining the middle profile and by evaluating on the vectors polygon the influential parameters (rays of the rings, inclinations, weights, etc.). The stress quality along meridians (Fig. 4) is quite similar to that achieved by the analytical method in closed form. The stress values remain still very low, and, at the impost of the dome, the average stress does not exceed 0.032 MPa. The stress along parallels is obtained very simply from the vectors Δi, as shown in Figure 5. The stress distribution along parallels is slightly different from that of the analytical solution: the compression stress grows proceeding from the top to the base (from 0.0045 MPA to a maximum of 0.0125 MPa). Fig. 6: FEM analysis: (a) stress along the meridians in the extrados surface; (b) stress along the parallels in the extrados surface; (c) trust line

FEM analysis with shell elements The “Straus7” program was employed in order to make a numerical analysis by the finite element method (FEM). Such program – utilized thanks to the important contribution of our colleague Giuseppe Berti from the University of Florence – allowed us to carry out a linear elastic analysis using plate/shell finite elements characterized by both membrane and bending behaviour. The elements (called Quad4) are characterized by four nodes with six degrees of freedom for each node. The mesh was generated considering a parabola as revolution curve (discretized with 44 elements) that was turned around the dome revolution axis (generating a total of 4128 elements). Each element is characterized by a thickness that takes into account the real thickness of the dome, which varies with height. The nodes at the start of the dome were bound with hinges that allow rotations. Such constraints prevent the transmission of bending moments that are not plausible for masonry material (and in particular for earth material). The results obtained by this analysis are shown in Figure 4 (where the variation law is described concerning the parallel and meridian stress, sampled on the middle surface in order to allow a comparison with the results of other methods) and in Figure 5 [where the parallel and meridian stress is described, relating to all the elements, on the extrados surface (a, b) and the trust line within the dome section (c)]. It is important to note (Fig. 4) that the FEM solution is very close to the analytical one, both in terms of quality and quantity. In particular, as regards the stress on the parallel, the maximum stress is located near the median parallels with a value of about 0.0121 MPa. The most interesting results regard the trust line that highlights the membrane behaviour of the dome (Fig. 6), since the trust line practically coincides with the middle profile of the dome (Heyman 1977).

Fig. 7: FEM analysis on an incomplete dome: (a) stress along the meridians in the extrados surface; (b) stress along the parallels in the extrados surface

stress (and provides negative stress values plentifully below the strengthening level) fully performs the adopted procedure. Also the results of the proceedings conducted by the membrane theory are very similar in quality and quantity. In both cases there is a solution without tensile stress: as on the parallels (with the graphic way highlighting a monotonous law), and on meridians (where the values of the stresses are comparable, with slight differences depending on the choice of a constant section profile in the analytic solution). But perhaps these assessments may seem reductive. What emerges from the evidence of mechanical checks is the surprising ability to combine housing performances with static efficiency. It appears that the long selection process, intelligently implemented by natives of the region of Aleppo, produced a resounding success. The dream of physicists and modern structural engineers – to achieve the most suitable and economic shape for assigned material and loads – here looks like coming true, by chance, stubbornness or, perhaps, out of necessity. The constructive weakness of the device seems essentially dependant upon the system of supports and the fragility of material. List of References Benvenuto, E. & Corradi, M. 1988, ‘La statica delle false volte’, Nel cinquantenario della Facoltà di Architettura di Napoli, Franco Jossa e la sua opera, Napoli. Briccoli Bati, S. & Rovero, L. 2001, ‘Natural additives for improving the mechanical properties and durability of adobe building material’, Mats. Eng. Journal, 3 [12]. Briccoli Bati, S, Rovero, L. & Tonietti, U. 2008, ‘Considerations on methods to evaluate the compressive strength of earth building materials’, International Conference “Terra 2008”, Bamako. Flügge, W. 1962, Stresses in shells, Springer-Verlag. Heyman, J. 1977, Equilibrium of shell structures, Clarendon Press-Oxford, Houben H., Guillaud, H. 1989, Traité de construction en terre, CRAterre – EAG, Parentheses, Marseille. Mainstone, R. 2001, Development in structural form, Oxford Architectural Press. Pizzetti, G. & Zorgno Trisciuoglio, A.M. 1980, Principi statici e forme strutturali, UTET, Torino. Timoshenko, S. 1959, Theory of plates and shells, McGraw-Hill Book Company.

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The static of Aleppo domes and the reasons for their shape The static analysis that we carried out on a typical dome in the region of Aleppo confirms some insights concerning the mechanical behaviour of such devices. The idea that the structure might be thought of as a device equipped with a special joining, guaranteed by a material and a constructive process capable of achieving the state of ‘earthen conglomerate’, is confirmed by the results of the employed calculation models. First of all, it is important to emphasize the convergence of the results obtained with procedures based on very different models. The analysis conducted under the assumptions of the ‘membrane’ theory are realistic as long as the average surface does not deviate too much from the real ‘channel’ through which loads move towards the ground (and through the solid). Such feature is highlighted by the finite element solution characterized by shell elements: the resultants that run inside the section of the dome, deduced on the basis of the main stress on the meridian direction (read both in intrados and extrados sides), deviate from the average line only for few centimetres (less than 3 cm on a 50 cm length). This is especially important because it can help us to understand the quality of the static condition that characterizes the examined domes. Not only is the entire system uniformly compressed, with no stress value exceeding acceptable values for earthen material (note that the maximum stress is lower than 0.04 MPa), but, surprisingly, the shape of the dome seems, without hesitation, close to the funicular surface due to its own weight (i.e a dome shape as the optimal geometrical choice for that material). It is to be emphasized that, for once, the results from numerical models such as those analytically derived are very similar and comparable both as magnitude and trend. In particular the numerical solution, carried out on the basis of an elastic linear model, could be inappropriate looking to the nature of the material (certainly not iso-resistant), but a solution that excludes positive

University of Florence, Italy

The analysis of the structural behaviour of a ‘complex’ building system, such as the housing units of the Aleppo region, calls, to be completely trustworthy, for a real and deep comprehension. Knowledge of the technical steps in the building process is fundamental (Besenval, 1984). In other words, an interpretation of an inadequately described building system is a risk: hypothesis and ideas may be far from reality. For this reason, we need to reproduce an in-scale earth model representing a base unit in order to achieve those dual purposes: - to reconstruct the building process - to subject the in-scale model to external forces and test the vulnerability found on prototypes. The first intent is suggested by the need to investigate the building technique, still indeterminate as to the possible versions; the second is indispensable for valuing the mechanical responses of the building, useful for a final interpretation of the structural behaviour and also for a validation of the numerical solutions. Such a model must reproduce each single brick and the main features of the constructive technique: we chose the 1:5 ratio, which allowed an easy manufacturing of the adobes and an easy management of the model in the laboratory of the University of Florence. A group of graduating students worked on this subject as their degree theses, supporting the University of Florence research team and increasing the quality of analysis and interpretation; in other words, the model could not be built or the consequent deductions done without their intervention.

have been obtained, while base box dimensions have been a little regularized and brought back to square. It was useful to build a basic but exact model for building techniques. Final sizes are shown in Figure 1. As in reality, we have two kinds of bricks: 80 x 40 x 20 mm for the walls; 80 x 40 x 15 mm for the dome (in this case the exact scale conversion has been adapted to make them more workable). For substituting the original material we found clayey earth in Valdarno (Tuscany), with features similar to that found in the Aleppo region. The mineralogical analysis on samples of adobe earth (both from the wall and the dome) taken on the mission to the Aleppo region, guided us in selecting the Valdarno earth, which has a percentage of clay and therefore a plasticity comparable to the Syrian earth.

Geometry, materials, and mechanical properties After the surveys made by the surveying team with laser-scanner technology, dimensions of a “middle size” type cell have been isolated. From the prototypes the outlines of the dome both in middle and diagonal sections

Tab.1: Main mineralogical composition of the earth of the in-scale model

Clayey minerals composition of the earth of the in-scale model The mineralogical analysis highlighted that the earth from Syria is characterized by a medium clay percentage of 37,5%, of which a small part is expandable minerals that increase slightly the plasticity. These earths also have a remarkable percentage of calcspar, which, though thin in granulometry, gives a relatively lean behaviour to the whole. Synthetically, the analysis has shown that the adobe earths of the Aleppo region are relatively lean. The mineralogical analysis conducted on Valdarno’s earths led us to a soil in Terranuova Bracciolini where the mineralogical composition is slightly different from the Syrian, but the clay percentage and the plasticity levels are close. The results of the analysis are in the table below (Tab. 1-3). Quartz 35

Kaolinite 15

Feldspar 30

Illite 30

Chlorite 15

Clayey minerals + other 35

Chlorite vermiculite 15

Tab.2: Clayey mineral composition of the earth of the in-scale model

Vermiculite 25

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The earthen in-scale model and the mechanical tests

Dalia Omar Sidik, Mirta Paglini, Elena Peducci, Flavio Ridolfi, Luisa Rovero, Ugo Tonietti

It is a rather a lean earth (note the high quantity of quartz and feldspar) but in the clay minerals that it contains, the percentage of expandable reticule minerals (the mixed vermiculite and chlorite stratum and the vermiculite stratum) increases the earth’s plasticity making it comparable to the Syrian. The material used to build the model has been also mechanically examined with a monoaxial compression test on samples done from the small adobes used for the wall (80 x 40 x 20 mm) according to the directions of the RILEM Technical Committee 164 (Briccoli Bati, 2008; Morel, 2005). Three samples have been produced from two half adobes laid one on top of the other with a mud mortar joint as the one used in the model, obtaining an almost cubic form (40 x 40 x 45 mm) (Figs. 3a-3c). Below is the load/displacement graph of one of the samples and the table with the mean values of the main mechanical parameters determined (Fig. 2). The table shows how the compression resistance is similar to that recorded in situ by the sclerometer.

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Earthen Domes and Habitats Fig. 1: Final sizes of the earthen in-scale model.

Compressive strength (MPa) 1 1.25 2 1.58 3 1.70 Average value 1.51 Standard deviation 0.23 Variation 0.15 coefficient

Specimens

Elastic modulus (MPa) 109 79 83 90.33 16.29 0.18

1.85 1.90 1.40 1.72 0.27

Available kinematic ductility 1.85 2.90 3.60 2.78 0.88

0.16

0.32

Kinematic ductility

Tab. 3: Main mechanical parameters resulting from the monoaxial compression test

Fig. 2: Plot-load displacement relative to monoaxial compression test on sample 1. Figs. 3a-b-c: The sample and the test setup.

Constructive solutions and making a ‘pre-model’ A very important point was the choice of the ‘type’ of dome to reproduce. As stated, the region studied presented a certain variability of technical solutions, depending sometimes on the environmental context (availability of

Test apparatus and model theory reference We said that the realization of the model follows two fundamental targets: on the one hand, to verify techniques and processes, on the other the need to test the model in the laboratory to highlight the main mechanical require-

ments. From this point of view we thought it useful to arrange a test apparatus which allowed to simulate ground settlements, because the weakness found in the prototypes showed diffused cracking in the corners and separation of the faces, phenomena that are probably due to differential settlements of the base or to deficits in the supporting functions of some special constructive texture. We chose to recreate the sinking in just one of the corners, taking care for the realization of an articulated steel support which also allows us to display possible differential settlements between the two orthogonal walls (to test possible shortcomings in the scarf joints of the walls). This apparatus, entirely built in the laboratory of the University of Florence thanks to the ability of the technician Aldo Regoli, is shown in Figure 5, which also describes the mechanical devices arranged with this aim. Though a qualitative evaluation

Fig. 4: The pre-model development.

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wood or stones, quality of the earth), and at other times on the cultural (shape and distribution of the house, constructive choices). As for geometrical references, the problem has been solved choosing the ‘type’ with a vertical wall (common and more recent), offering moreover samples of a fair architectural merit. This type may have been successful due to its highly developed vertical walls and the ‘squaring’ of the room, factors that aid the contemporary use of the house. Much more complex was the choice of some constructive options characteristic of the object. The main problem was how to build the pendentive and solve the connection between the square base and the circular impost of the dome, which has a decisive influence on the mechanical performances. Together with the vertical three head wall’s corner, it is a critical point of the cell, to which the constructive culture of Syrian villages offered many different answers. In fact there are many buildings where those connections are ‘delayed’ by inserting a particular piece (earthen brick, wood or stone) in a relatively high position. It has the responsibility of forcing the change to the shape of the corner with its overhang. This solution is clearly based on the attempt to keep the room squared and the walls vertical as much as possible, but it enhances the mechanical role and the connected fragility of this special solution in the connection between the right angle and the curve of the dome impost. A different solution, also used in the chosen prototype cells (though less often), consists of a very complex brick disposition that deforms the corners and begins the transformation to the circle. This approaching to the circular shape is made by disposing the adobes in an overhang, moving away from the vertical and creating a surface ideally close to a spherical sector, which allows a gradual connection. It appeared more interesting to re-build this last device, certainly more difficult and enigmatical, but it is still open to question concerning construction and behaviour. In order to speed up the building of the earthen model we thought it was helpful to produce a study model in a reduced scale (1:10) made in a light plastic material (polystyrene) in which to test the more complex technical solutions (Fig. 4).

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Earthen Domes and Habitats Fig. 5: Steel support able to induce different settlements and the placing of the displacement gauger.

Model construction Producing the models, in polystyrene first and in earth later, revealed very important issues. In the first case, the assembly steps showed how bricks must be cut both in building the base box and in the difficult halo disposition in pendentives. It was also decisive to verify the building of the continuous spiral path of the elements and the stability problems seen in the last rings. What matters most is the understanding that the ‘spherical pendentive’ device undoubtedly represents the adoption, in the domes with vertical walls, of the solution used in simple domes, those which keep a substantial continuity in building work from the base to the top. This generates the weakness of the external faces in vertical walls starting from a certain height. The building process with earthen bricks familiarized us with the executive technique. Making adobes (based on the proportions gave by local craftsman, 3/4 of earth and 1/4 of minced straw) was carried out after careful selection of the materials and mixing, to get a realistic in-scale reproduction of the Fig. 6: Material mixture and brick making.

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is enough for our purpose, knowing the tenacity of models in withstanding even the worst actions (in-scale constructions have a lower strain level), we thought it opportune to arrange a convenient overload. As known in ‘small size’ constructions it is possible, thanks to the theory models, to simulate completely the stress condition of any system. In order to do this, the model must be overloaded (Buckingham or π theorem) remembering that the density of the material is constant while the volume changes (Fumagalli 1973). This can represent a problem in structural tests, because the way loads are added may distort the mechanical behaviour, both because they cannot be uniformly distributed on the frames, and because transmission devices may strongly condition the displacements. Here we opted for a simple overload made with sacks of sand and lead distributed along the external perimeter of the walls in order to reproduce the stress condition due to the wall’s own weight. Besides this we also added more load in a corner portion of the dome not to reproduce the original strain condition in a part of the dome, but to allow a simulation near to reality of the strain condition in the zone of the pendentive and the wall. Total overload was 1,300 kg added to the model’s own weight of 480 kg. The displacement process was kept under control by millesimal comparators recording each displacement.

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Earthen Domes and Habitats Fig. 7: Earthen model building phases.

original (Fig. 6). The brickwork follows the scheme, discovering the need to fill up the spaces with mud mortar, especially in the pendentive curving. Owing to our lack of experience, we had to resort to a paperboard guideline to obtain the right shape of the dome’s intrados; the spiral path has been easily made changing the thickness of the mud mortar. It is surprising to see how the brickwork, which needs a large amount of mortar in its construction to fill up the empty spaces, suddenly turns into a single object, consequently achieving resistant capacity. This happens particularly in complex points like the pendentive curving and the last rings of the dome where, without the fundamental aid of the mud mortar, the structure may collapse. Finally, a thick plaster coat, always made of the same mud mortar, was given to the external faces (as with real domes), except for a portion to see the disposition of the adobes, in order to confirm the decisive structural role covered by filling up with wet earth (Figs. 7-8). The tests Applying displacement to the model highlighted unexpected resistant qualities. After the first phase, when walls seemed indifferent to the assigned displacements testifying to the high solidarity at the corner where a base sinking was simulated, the structure reacted in an unexpected but coherent way with an augmentation of the sinking. Those actions (not even when expressly led)

could not bring an important disconnection to the middle of the pendentive (or to the external corner). Here we had a little spacing between the elements, though the real phenomenon of discontinuity was affected: at the beginning the external face at the middle of the base wall (the one close to the given displacement) showed a separation between the broken external skin and the inner shell; then, increasing the level of sinking, the crack ran transversally along the wall to connect to a new and similar one that was opening in the contiguous wall (the two walls joined on the stressed corner) producing a kind of discharging arch substantially able to separate the dome from the walls below. The shape of this crack in the two incidents of the vertical face walls simply reflects the sequence of settlement (Figs. 9-11). At first, displacements touched just one of the box sides and then they were followed by similar ones on the other side, so producing a temporal asymmetry then reflected on the different path of the cracks. The most remarkable thing to come out of this is the extreme solidity of the brickwork in the corners in comparison with the higher fragility of the vertical wall brickwork. In the end we still maintain the ascertainment analytically made previously about the excellent resistant capacity of the ‘dome device’ when considered separately. It uses all its constructive continuity stemming from the spiral path and has just one small weakness localized in the final ‘closing’ rings.

Fig. 8: The earthen model plastered side.

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Deductions about the mechanical features of the system Certainly the test gave some important results. Confirming the important contribution of the model for the comprehension of the constructive techniques and to clarify some delicate steps of the building process, the most surprising results came from the mechanical tests. Those highlighted a feature that was unexpected in the preliminary stage. It is the substantial difference in behaviour between the two fundamental typology of domes, to which are attributable a large number of versions: the simple dome and the Sultan dome. In fact the model we made, which has pendentives with spherical-continuous surfaces, reproduces the static scheme of the older typology, the one resembling a tent and perhaps more uncomfortable for living. Now it seems certain that in this kind of device the continuity at the corners and a global continuity prevails in the simple domes from the top to the ground, even with a little forcing of the square base. On the contrary, the domes having high vertical walls present the greater weakness right at the corners, because in that case the discontinuous box scheme prevails and the weakness of the connection with the circular impost of the dome is clear. Without intending it, in our model we built something constructively close to the â&#x20AC;&#x2DC;continuous conoidâ&#x20AC;&#x2122; cell, despite building one with vertical walls, and then we saw a behaviour in which corners are stronger than walls. To sum up briefly, the difference between the two static behaviours is that in the simple dome the circularconoid construction prevails almost to the ground while in the royal type we have two different devices (the dome and the wall box) showing the main problem to be in the discontinuity of the corner. In the first case the walls standing out of the main tension flux (which follows the path of the conoid surface) weaken both because they are constructively independent and because they are functionally not so influential (Figs. 12a-c). Vice versa, in the Sultan dome case, the tension flux coming from the dome meets no contiguous brickwork and must face a box whose weakness is right at the connection of the corner (Figs. 13a-c). The last open question is why, during the building of the continuous pendentive the filling mud mortar efficaciously solidifies the broken adobes, while where it has to do this between the external face and the internal shell in the higher part of the vertical wall in the middle, it cannot. The answer may be found in the tension flux: as where it is continuous and firm it produces a compacting action, in the top of the wall and far from the corners the overload is not enough and the external

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Earthen Domes and Habitats

Fig. 9: First step: separation between the external skin and the inner shell.

‘skin’ is too thin. It must be stated that in this test the overload condition was less powerful (for geometrical reasons) over this area. Our clear feeling is that the mud mortar role is fundamental in ‘explaining’ how to get that kind of monolithic-conglomerate necessary for the existence of a dome like this with the given geometry. This gluing also seems clear where the brickwork, as it is in the model pendentive, requires a large use of mortar and, on the contrary, it is minimum where the bricks prevail over the earthen mortar. List of References Benseval, R. 1984, Technologie de la voûte dans l’orient ancient, Tome 1, Edition Redherche sur les Civilisations, Paris. Briccoli Bati, S., Rovero, L. & Tonietti, U. 2008, ‘Considerations on methods to evaluate the compressive strength of earth building materials’, International Conference ‘Terra 2008’, Bamako. Morel, J-C., Pkla, A. & Walker, P. 2005, Compressive strenght testing of compressed earth blocks, Elsevier. Fumagalli, E. 1973, Statistical and geomechanicals models, Ed. Sprinter-Verlag, Wien.

Fig. 10: Second step: dilatation of the cracks L1 and horizontal development of the crack L2.

Fig. 12a: Simple dome: structural behaviour interpretation.

Fig. 12b: Simple dome

Fig. 11: Third step: discharging arch resulting from the union of the cracks L2 and L3. Separation between the dome and the walls below.

Fig. 13a: Sultan dome: structural behaviour interpretation.

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Fig. 13b: Sultan dome

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For a sound knowledge of historical monuments and to be able to thoroughly approach a restoration project, the use of precise diagnostic methodologies and techniques is essential for ascertaining the actual materials and causes of degradation, and to then arrive at a diagnosis and determine possible solutions. The advanced structural calculation procedures developed by Continuous Medium Mechanics have recently provided very powerful tools for the analysis of increasingly more complex structures. Among these methods, the Finite Element Method (FEM)1 has been most developed. However, applying the FEM to analyse the condition and behaviour of historical structures is rather more complex, since in order for the results to be reliable certain conditions relating to its application are required in the analysis and fundamentally the use of non-linear models. To approach the analysis of these structures, the structural concept and the methods under which the domes were designed and built must be taken into account. These structures were conceived and built using unknown parameters, since concepts such as strain, strength and deformability, which are judged as essential for the understanding of structural behaviour, were then unknown. The mechanical behaviour of fabrics is far removed from that which is assumed in the lineal analysis2. The joints and possible fissures cause a loss of material continuity; the mechanical properties depend on the tension forces applied; there is no linear relationship between tensions and deformations, etc. These effects emphasize the fact that the lineal analysis does not correctly reproduce the behaviour of historical buildings; we can only expect for an approximation to structural reality that will be divergent to varying degrees according to the conditions of deformation, tensions and deterioration of the fabric itself, besides that of the mortar and its components. Thus appears the non-linear analysis, which attempts to evaluate the behav-

iour of structures using the properties of materials that are variable. To construct a model of this variability makes the analysis extremely complex. In the FEM this involves an evaluation of the constitutive matrix according to the concepts of the theory of plasticity and the mechanics of fractures. This process is necessarily non-linear, and therefore repetitive, which involves an increase both in complexity and in computational time. The appearance of fissures in the fabric, and the variation in the tensiondeformation conditions which they cause, necessitate the inclusion of fissurisation modes in the applied analytical models in order to obtain realistic structural results in the study. There are three basic procedures of non-linear analysis3 on which to model this non-linear behaviour of structures, calculating the appearance and evolution of fissures and the maximum structural loads. The so-called isotropic damage model was used in this study4, which was utilised within the CID programme5 of finite elements for the study and analysis of various historical domes, and of which we give an abbreviated description. In the case of the Syrian domes studied, the material used was adobe or sundried clay bricks. The property which characterizes these materials is their low tensile stress capacity. Compared to acceptable compression strength, tensile strength is much lower. Different researches6 coincide in attributing mechanical values to clay fabric and materials, depending on those established for the foundation base material, which in the case of adobe, were estimated to range from 1 to 1.5 N/ mm2 of compression strength. The values for tensile strength were 10 times lower, averaging around 0. 01 N/ mm2. The domes studied are representative of a common habitat in the region, with only one small sized living space, a value geometry comprising dome diam3 4

1 2

Zienkiewicz & Taylor 1994. Lourenço 1998.

Polytechnic University of Valencia, Spain

5 6

Oñate & Hanganu 1999, pp. 303-316. Oller 2001. Alonso Durá 2003. Huerta Fernández 1990; León, Martín-Caro & Martínez 2001.

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A numerical no-tension code application for the dome structural analysis

Adolfo Alonso Durá Arturo Martínez Boquera Verónica Llopis Pulido

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eters ranging from 4 to 7 metres, approximate wall thicknesses of 50 cm and approximate dome thicknesses of 35 cm. The dome was modelled in combination with the walls using mesh of volumetric finite elements in the intrados and batter, resulting in a model with 18,370 nodes, 82,180 solid tetrahedron elements and 54,762 degrees of freedom (gdl) (Fig. 1). Initially, analysis assumes that the structure is formed by a continuous material of lineal-elastic behaviour, and the parameters are specified through the constitutive matrix. It requires comprehensive information of the mechanical properties, which, as we have pointed out before, can be an area of conflict. The mechanical characteristics of adobe as a material used in the model were assumed from the mechanical tests carried out at the Dipartimento di Costruzioni of University of Florence (see previous contribution) as follows: Young Modulus E= 4000 N/mm2; Poisson ratio ν= 0.2; Bulk density γ= 1900 kg/m3; Compressive strength σ= 1.5 N/mm2; Tensile strength σt = 0.01 N/ mm2; Fracture energy G=0.05 Nmm/mm2. From the study of structural behaviour under the gravitational load hypothesis, with a non-linear calculation procedure7, following an isotropic damage model8 and implementing it in the CID program9 of finite elements, a stress state (Figs. 3-4) and damage rate (Figs. 5 and 6) are obtained showing excellent structural behaviour. The state resulting from the calculation under tensional gravitational actions shown in Figs 5 and 6, shows that the tensional state Sx (Fig. 3) in the direction of the parallels, ranging from a compression stress of -0.014 N/mm2, very far from the allowable strength of the material, and tensile stresses, in red colour, concentrated in a very low value items of 0.029N/mm2, values are also very low and perfectly acceptable for the material of construction, including traction. Likewise, the tensional state Sy (Fig. 4) in the direction of the meridians, only varies between compression and voltage values of -0.08 N/ mm2 and -0.007 N/mm2. Similarly, the displacements that occur in the dome, under gravitational loading, are also very low. Fig. 2, shows the map of vertical displacement, which in the upper part range between 0.07 and 0.01 mm. In this analysis, the non-linear damage model described above, seen under gravitational loads, is an almost total absence of the level of damage (Fig. 5), with a damage index between 0.2 and 0.4. The collapse occurs in a hypothesis of 6 times the gravity load that is subject to the dome (Fig. 6), which shows 7 8 9

Alonso Durá 2003. Hanganu, Barbat & Oñate 1997. Alonso & Pérez García 2002.

the considerable safety of this type. This conclusion is also supported by the actual model given that no relevant fissure was found therein. Conclusions Although the material of this type of construction is of very low resistance, the shape, size and thickness of the dome and the walls justify the low value of the tension that is subject to both compression and traction. The inexistence of any set of real fissures in the domes is consistent with the stress state shown in Figs. 3 and 4, both in the direction of the meridians and parallels. Additionally, the shape and dimensions of this type of construction, provide a high level of stiffness, so the gravitational vertical displacement under load is not significant, consistent with the low stress state. The vertical displacements are not significant (Fig. 2). For this reason, the influence of elastic constants in the analysis, since their values are very low or insignificant, is irrelevant. The map of damage obtained in the calculation of the effect of the gravitational loads is inexistent (Fig. 5) and to reach a collapse it would be necessary to increase these gravitational loads by up to six times their current value, (Fig. 6) which guarantees the high degree of safety of these buildings.

List of References Alonso, A. & Pérez García, 2002, A Manual de usuario del programa CID (Programa de cálculo de estructuras por Elementos Finitos desarrollado en el Departamento de Mecánica de Medios Continuos y Teoría de Estructuras de la Universidad Politécnica de Valencia), Valencia. Alonso Durá, A. 2003, Un modelo de integración del análisis estructural en entornos de CAD, para estructuras de edificación, Tesis doctoral, Valencia. Hanganu, A. D., Barbat, A.H. & Oñate, E., 1997, ‘Metodología de evaluación del deterioro en estructuras de hormigón armado’, Monografía CIMNE nº 39, Barcelona. Huerta Fernández, S. 1990, Diseño estructural de arcos, bóvedas y cúpulas en España ca. 1500ca. 1800, Tesis doctoral, Madrid. León, J., Martín-Caro, J.A. & Martínez, J.L. 2001, Comportamiento Mecánico de las Obras de Fábrica, Departamento de MMCYTE, Escuela Técnica Superior de Ingenieros de Caminos Canales y Puertos, U. P. Madrid. Lourenço, P.B. 1998, ‘Experimental and numerical issues in the modelling of the mechanical behaviour of masonry’, Structural Analysis of Historical Constructions II, Barcelona. Oller, S. 1991, ‘Modelización Numérica de Materiales Friccionales’, Monografía CINME n° 3. Oller, S. 2001, Fractura mecánica. Un enfoque global, CIMNE, Barcelona. Oñate, E. & Hanganu, A. 1999, ‘Métodos avanzados para el cálculo de la resistencia última de estructuras de hormigón’, Técnicas avanzadas de evaluación estructural, rehabilitación y refuerzo de estructuras, Valencia, pp. 303-316. Zienkiewicz, O. C. & Taylor, R.L. 1994, El método de los elementos finites, McGraw-Hill, CIMNE. Barcelona.

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Fig. 1: Model meshes of finite materials. Fig. 3: Stress state resulting from the calculation under gravitational actions. Sx based on parallels and Sy on meridians.

Fig. 5: Model of damage resulting from own weight load.

Fig. 2: Deformation as a result of own weight load. Fig. 4: Stress state resulting from the calculation under gravitational actions. Sx based on parallels and Sy on meridians.

Fig. 6: Model of damage at the point of collapse for 6 times the domeâ&#x20AC;&#x2122;s own weight load.

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Ten earthen dome villages of Northern Syria

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University of Florence, Italy

Emmanuelle Devaux

University of LiĂŠge, Belgium

We analyse ten villages of northern Syria, chosen as study cases for a specific and thorough analysis identifying the urban morphology and both architectural and constructional features studied in the previous parts. After visiting and inspecting three geographical areas (the region west of Lake Jabboul, the region west of Lake Al Assad, and the region east of Hama), ten villages were chosen because of their special architectural and urban features, and their significance regarding the architectural heritage, according to the following parameters: - relevance to the heritage: the significance and presence of architectural forms; - territorial context: special environmental and geographical features - population: the number of inhabitants, with close regard to the availability of resources and future population expectancies; - state of conservation and use: in relation to internal factors such as the configuration of the local community, and external such as the environmental context. A descriptive and graphical sheet has been made for the analysis of each village, starting with the location and geographical context study, the examination of population, the urban structure morphology, description of streets, roads and traffic circulation, and the architectural morphology analysis. For each sheet, a map of the context situation was made, and depending on the features of the villages, the entire settlement or a housing unit were surveyed, using in some cases traditional methods, or instruments such as topographic total station or laser scanner for a 3D geomatic modelling. This information was used for identifying the various urban and architectural typologies, along with the building materials and different uses of the spaces inside a village. In this way, a comparative reading of the dif-

ferent system of settlement and the architectural forms has been made, from which it was possible to identify the similarities and differences among the villages and at the same time, the architectural and constructive rules, in correspondence to the requirements of inhabitants and the availability of local resources.

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Ten villages of northern Syria

Letizia Dipasquale

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Location and context Oum Aamoud Kebir is a large village situated on the north side of the road between Aleppo and Khanasser. Located on an agricultural plain near the salt lake of Jaboul, it is notable for the presence of several distinct parts built at different times and clearly showing various stages of development. While many houses have private wells, a wide channel that is waterless in the dry season crosses the southern part of the settlement from east to west, isolating a small hamlet between the village and the major road link. Population A large community of farmers inhabit this village as a result of favourable conditions; the land is quite fertile and water for cultivation is in plentiful supply. The sedentary lifestyle and the availability of resources has sustained the levels of population. Many domes are still inhabited and in good condition due to constant maintenance and the traditional production of clay bricks, both for construction and repair. Urban structure morphology The village is served by the main road to the south and two secondary roads, one to the east and one to the west that converge to the north and connect to the main road. The eastern road, beside which stands the mosque, leads through a densely populated village area. The oldest part of the village lies on both sides of this road as far as the canal to the south. This area contains clustered and imbricated dwellings. The village developed towards the west, concentrated in the triangular space formed by the two secondary roads and the one to the south. Going westward, the arrangement of units becomes more compartmentalised into long, narrow plots. The units are also more extensive. The newer buildings are

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Oum Aamoud Kebir

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Circulation In the oldest area, pedestrian routes are understandably numerous and of a spontaneous nature, given the agglomeration of units. However, in the more modern areas where long plots lie at right angles to the roads, traffic moves directly from the road alongside the units. The most significant gathering place is in the vicinity of the mosque and shop. Architectural morphology As in many villages, we find here a mixture of building and domed roof types. These units are enclosed by long walls in the most modern parts, whereas in the older areas the layout of buildings designates the public and private spaces. The Sultanya or Sultan type domes are of good quality and seem to have been built by experienced masons. Many of them are still functioning, although those at the centre, in the oldest part, are abandoned and ruined. The buildings have a dimensional rather than constructional uniformity. Many domes are single or double, but groups of three to seven contiguous domes are not uncommon. A number of those in use have a lime plastering, especially in the southern facade to reduce the absorption of solar radiation.

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located mainly on the outskirts of the village and along both sides of the roads east and west. Here at the northwest point there is a mosque and a school. Even within the village some vegetation is present, mainly in the form of orchards of various sizes in private courtyards.

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D. Dwelling house F. Animal fence H. Stables, ‘Hazera’ or ‘Qabu’ K. Kitchen, ‘Matbakh’ S. Stores T. Terrace, ‘Mastaba’ W. Bathroom, ‘Marhad’ or ‘Baet Al-mai’ Well, ‘be’er’ Fireplace

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Location and context Oum Aamoud Seghir is a small village located mainly east of the road north-west/south-east, which connects Aleppo and Khanasser. It is built near an ancient site, the road of which runs through the village, and there is some reuse of elements from columns. The village is singularly located between a hill and the shores of Lake Jabboul, a hundred yards distant and connected by several small paths that lead across the plain. Although two small streams descend from the mountains towards the lake during the rainy season, vegetation and crops are absent in and around the village. Population The population of this small village remains relatively high and there is a school, rarely the case in settlements of this size. The inhabitants live mainly from farming and the sale of salt harvested on the shores of the lake. This activity is one of the main reasons for the perpetuation of this village, providing work and significant income for the households. Urban structure morphology Entrances to the village are several from the main road, especially towards the lake where the village is more developed. One finds a mixture of modern and traditional buildings here. Just a small group of dwellings at the southeast entrance to the village constitutes the old town. It consists of grouped and joined units, contrasting to the newer more regular units that have developed one by one and often in narrow

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Oum Aamoud Seghir

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Circulation The circulation system within the village is limited, given the many direct accesses from the road that end in cul-de-sacs. There is no cross traffic between lanes, all parallel to each other and oriented east/west. Only an alley, rather pedestrian in nature, transversely joins both ends of the village. The main gathering point lies in the area outside the shop, in the south of the village, though some groups meet between the road and the first buildings, depending on the communal activities taking place in the village. Architectural morphology In this village, the domes are of the Sultan type. The vast majority is in good condition, being still in use. This type of construction, however, is no longer used for new buildings, where cement and flat roofs are adopted instead. Most buildings display a simple coating of earth. Most housing units have long enclosure walls, of varying heights, except where there are significant alignments of domes, being multiples of small ancillary buildings, in the oldest units. These outer buildings may also be domed or have flat roofs. We thus find a mixture of architectural styles. In modern units, these other constructions are separated from the main house and all connected by walls.

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plots along the road to the lake. The older units show a denser pattern composed of many domes, including groupings of up to nine in number with small adjoining buildings. Recent units have a more dispersed framework with smaller domes.

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D. Dwelling house F. Animal fence H. Stables, ‘Hazera’ or ‘Qabu’ S. Stores T. Terrace, ‘Mastaba’ W. Bathroom, ‘Marhad’ or ‘Baet Al-mai’

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Location and context Rasm Hamd is situated in the Aleppo region, fifty kilometres south of the town, and to the west of Lake Jabboul, at an altitude of c. 400 metres above sea level. It spreads over gently rolling basalt slopes and is thought to have been founded on the ruins of an old probably Byzantine site, according to observations of some period materials excavated during digs near the centre. Population The village was built 250 years ago when Bedouins from the AlbuShabaan tribe originating from Yemen moved there from Raqqah. The population, which used to number around 2,000 people is now reduced to 500 inhabitants. The progressive desertion from the village is mainly due to the lack of water and productive activities which could make the community self-sufficient. The men, especially the young, travel to Jordan, Lebanon, Aleppo and Damascus in the search of seasonal jobs, while the women stay in the village to look after the children and perform daily tasks. Stockbreeding is the main activity of the population staying in the village. In winter, shepherds stay in the area when the surrounding land is favourable to grazing, whereas in the dry and hot seasons (spring and summer) whole families move to more fertile grounds and settle in their tents in the steppe area or further north near Sfireh. In this period the population is reduced to scarcely 150 or 200 inhabitants. Another activity is cotton picking in the vicinity, done mainly by the women.

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Rasm Hamd

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Circulation Inside the village the streets leave from two main squares. These main streets stretch from west to east following the natural slope of the ground, whereas secondary ways stretch from north to south. The road network is rather irregular and spontaneous. The various routes branch out and are lined with housing units. The primary schools and the mosque are the only public buildings, being of recent construction in reinforced concrete, away from the village centre. Water supplies The water, which is not suitable for drinking, comes from public and private wells (about 25 inside the village), whereas drinking water is brought to the village by a tanker, which also supplies other settlements. Drainage pipes follow the slope of the ground. Wastewater runs into small canals (10 to 15 cm deep) to be found in the courtyards of housing units, each connected to the drainage pipe system along the main streets. Architectural morphology The character of the village can be seen in its careful organisation, its practical and technical details and communal sewage system for each housing unit. The group studied includes three units (A, B and C) and is located in the area east of the centre of the village. These three form a small sector or quarter of their own. Two of them (B and C to the south) are more closely interlinked. To the north of unit A is another more dispersed

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Urban structure morphology Rasm Hamd has no planned urban structure. Only one road to the northwest demarcates the whole village, while the other boundaries are unclear. In fact, property spaces result from the spontaneous gathering of housing units around the basic cell, which is the domed dwelling. The housing units are rarely composed of single domes; they are mostly multicellular arrangements composed of domes of different sizes and uses built around square and rectangular courtyards. Each housing unit is usually inhabited either by an extended family nucleus or by a parental nucleus. Some of the units are isolated, others grouped together in twos or threes, and some others are surrounded by walls with their entrances on the main thoroughfare.

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and functionally independent unit. To the north of the two twinned units one can see another abandoned unit mostly in ruins; a limited space allows access between the two units. To the west of the units A, B and C lies an open space (used by vendors and others) and also another large housing unit across the 10 meter-wide street. To the east of the group lie two other housing units, one of which is situated on the other side of a large street. The other to the east includes a curved wall which forms a narrow alley along unit B and leads directly to unit A from the east, and also a straight wall which makes a larger passage along the eastern wall of unit A. This housing group has what functions as a semi-public passage. This passage follows the back faรงade of the twinned units and leads to the third. This space is both an alley when we enter from the east of unit C and a space belonging unit A with its own direct access from the high street and a private-looking entrance. Such a configuration is rarely met with. Unit A is the first we come across when arriving from the main road. It is enclosed by constructions to the north and by walls to the east and west. The south of the unit is not closed because it is the demarcating north wall of units B and C. There is a narrow street between the two. It has a single dome, which announces the entrance of the unit and serves as a secondary house. There is also a small dome which is used to store linen and dishes, attached to the unit and allowing communication from the inside. It is a large-scale niche that can be walked through. On the other side, a small common mastaba separates the entrance of unit B, and a well is to be found there. It is not rare to see several entrances but in the case of this medium-size unit they are relatively numerous. There is similarly another passage to the unit in the east wall. The other constructions in this unit have flat roofs. Clay is used for the kitchen and the toilets, rubble stone cement for the main house and the barn. Here the sewage system works well because the water does not stagnate in the courtyard due to the natural slope of the terrain. A small wall diagonally divides the rectangle made by the units B and C: one lies to the east and the other to the west. There is in this case a common a sewage system, again making use of the natural slope of the terrain since the waters from B drain into C and are eventually carried into the modest gutters of the street to the east.

The entrance to unit B is situated to the south of unit A between the common mastaba and the small wall. It has five domes of which two are used for living, one for washing and cooking another for kitchen only (fridge, pantry) and the fifth for heavy material (motorbikes, etc.). There is also a rectangular henhouse made of clay. This unit is full of details especially the handrails and the staircases, used as access to the dome. Here everything is well thought out and each detail has its use. Unit C and its entrance is to the west of unit B. In front of the entrance to the dome there is a mastaba. The whole unit has six domes and a flat-roofed rectangular construction and two large mastabas. It is difficult to say what each room is meant for because it is uninhabited. Some rooms are closed and others empty. However, we can clearly distinguish the main living quarters in the two domes to the north that communicate from the interior; two domes to the east are used for storage, two to the south for cooking and storage, along with a pen for livestock and farming equipment. The kitchen dome has a beautiful bell-shaped chimney at the summit: this detail is quite rare because the ventilation is usually found in the sides of the dome, usually quadrangular or triangular in shape. This ensemble of the three units reflects the architectural particularities of this village which stands out from most of the others studied by the attention paid to technical, architectural and sanitary details, signs of a superior quality habitat.

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D. Dwelling house F. Animal fence H. Stables, ‘Hazera’ or ‘Qabu’ K. Kitchen, ‘Matbakh’ O. Oven S. Stores T. Terrace, ‘Mastaba’ W. Bathroom, ‘Marhad’ or ‘Baet Al-mai’ Well, ‘be’er’

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Location and context From Oum Aamoud Seghir a road runs west, perpendicular to the road bordering the lake, connecting Lake Jabboul, Aleppo and Khanasser. It runs through a fertile valley between rocky hills to the village of Fejdane, notable for its shape and concentric organization and for the presence of large domes. Population Most of the 4,800 people in this village are from the Hariri tribe. The population fluctuates according to the seasons and associated activities. The village has a school that provides training up to the ninth grade. Thereafter, students, and mostly the boys, go to Sfireh. The majority of the population lives on agriculture and livestock, though a significant part of the male population earns money outside the village in the larger neighbouring cities. Urban structure morphology Access to the village is by the road to the northeast, which is connected to the Aleppo-Khanasser highway. Most of the village is concentrated within limits established by hills beside the roads to the west and north, and to the south and east by a large canal that lies alongside the street and serves this part of the district. Some homes are also positioned on the other side of the canal. The units of the older houses are mostly joined, agglomerated or overlapping. They are large and diverse in form, whereas the newer units are smaller and easier to distinguish one from the other.

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Fejdane

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Traffic circulation The streets are numerous and vary greatly in size, owing to the unplanned nature of the agglomerate and the surrounding road. It is possible to enter the village and go directly to the centre from all radiating access routes. As a result, pedestrian pathways are not present because the road network is so developed. At the heart of town, several large public spaces are used for groups or group activities. Some of them have several orchards (palm and fruit trees), and there are also garden spaces within the village. Architectural morphology In this village, the domes are of the Sultan type. There is a certain homogeneity of buildings in this village, since the domed buildings are relatively similar to each other. Most domes are still used and are often covered with lime plaster, which has resulted in an excellent state of preservation. The most recent buildings, made of cement, are predominantly located on the outskirts of the village. Indeed, to the north and across the channel, the units are mostly flat-roofed buildings with few domes, in groups of only two to three. We can see the heart of the old village lying from east to west, between the canal and the hill. The units include a multitude of domes up to a series of thirteen contiguous domes, although they may serve two or three separate units. Groups of five to ten aligned domes are frequent, making it quite a remarkable village from this point of view.

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In this town there is a certain amount of vegetation maintained in both private and public spaces.

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D. Dwelling house F. Animal fence H. Stables, ‘Hazera’ or ‘Qabu’ K. Kitchen, ‘Matbakh’ S. Stores T. Terrace, ‘Mastaba’ W. Bathroom, ‘Marhad’ or ‘Baet Al-mai’ Well, ‘be’er’

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Location and context The village is located on a hillside and is bordered to the south by a road that separates it from a wide, fertile valley. Expansion is limited given its geographical context between the valleys. Population The constant population is small in this village, which does however still have its own school. As with most towns in the region, the population derives its resources from livestock supplemented by some agriculture. Urban structure morphology There are accesses to the village from the main road, which forms the southern boundary of the village. The modern areas lie along the roadside boundary and north towards the hillside. It is noteworthy that the old village core centres on the flattest area of the site and has little of added modern buildings. The layout is unclear and the units are separated from one another without any particular visible organization; areas of property are not marked and are often relatively open compared to other villages where units are surrounded by large walls. There are no significant watercourses reaching the village from the surrounding valleys in the rainy season. Consequently, vegetation is largely absent except for some gardens in the west. Traffic circulation Pedestrian and informal traffic routes are numerous towards the inner

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El Raheb

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Architectural morphology This village, although small and with few new concrete buildings, boasts a great variety of architecture. Indeed, the two main types of dome are present here: the Sultan type, with a large perimeter base, and single dome with a low perimeter base. The latter type is the most frequent for older domes, which also correspond to those most abandoned. Indeed, the low base reduces the height of the internal space and is less convenient and appropriate to the contemporary lifestyle than the Sultan dome, the presence of which is predominant in Er Raheb. The manufacture of these domes demonstrates a skilled workforce, followed up by excellent maintenance. It is surprising to see such a variety in size and shape of dome. Some domes are worked with architectural details, particularly the slope at the top of the base to lead off rainwater and avoid stagnation at the junction of the dome. We also found some moulded decorations above the openings. The widespread use of basalt stones should be noted, specifically for the construction of bases. Coatings of lime are often used, but on walls rather than domes.

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village away from the main road. The spontaneous nature of the location of units makes for an unclear organisation of streets. The arrangement of the units is relatively unmethodical and many common spaces can be identified, which may be used for various activities.

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D. Dwelling house T. Terrace, â&#x20AC;&#x2DC;Mastabaâ&#x20AC;&#x2122;

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Location and context The area in which Rbaiaa is located, comprised of many small farming villages, has been completely redesigned by the presence of human activities such as the cultivation of cotton. Labourers have cleared the fertile soil of many rocks impeding their work, which have been arranged along the boundaries of agricultural plots, creating an irregular grid in the landscape. Rbaiaa lies at the foot of a small hill that overlooks two villages. Its Byzantine origins are visible in the surroundings and in many homes that have reused ancient stones in their construction. Population From the beginning of the dry season, there remain little more than a thousand people in the village. More than 500 leave for seasonal work, some even go to Jordan. The village does not have its own school, most girls stop their education early and begin harvesting cotton, which is sold to the government. Within the town a new municipal visitorsâ&#x20AC;&#x2122; building has been completed. Urban structure morphology Access to the village is made from several routes, directly connected to other villages or to the main road. The old village is concentrated in the middle and north of the present settlement, within the encircling road. The modern area, with concrete buildings, is located mostly in the southern half and in different places outside the perimeter of the village, while not altering the original urban structure. The units are clearly separate

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Rbaiaa

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Traffic circulation The streets are multiple given the road encircling the village and the spontaneous nature of the housing units. It is therefore possible to cross easily from east to west and north to south in the village. However, only a limited number of roads are available for cars that serve the majority of units in small access routes radiating from the main road. Large open spaces are visible in the village where some of the old abandoned buildings have now disappeared. These spaces can be used occasionally to carry out collective activities outdoors. Architectural morphology Like the village of Er Raheb, Rbaiaa is a small hamlet with, nevertheless, a great variety of architecture. The two main types of dome are also present here: the Sultan dome and the single dome. There is also the almost systematic use of basalt stones to build the foundations that often extend into door frames. It should be noted that there are as many variations in the height of the base as there are numbers of domes in the village. Their achievement demonstrates an excellent mastery of constructional technique, exhibiting a double elliptical dome pole and wooden beams, and numerous architectural details, both functional and aesthetically ingenious. Currently, maintenance is scheduled for only part of the village, since a number of domes are no longer used for storage. Similarly, coatings of lime are rarely used. However, a unit occupied by an old woman alone in the northeast of the village is an exemplary model of this type of architecture and maintenance.

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from each other without organization on a pre-laid out plan. The old units are notably closed, unlike the modern open variety. There are no rivers and other than some fruit trees vegetation is virtually non-existent.

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D. Dwelling house E. Hen house F. Animal fence H. Stables, ‘Hazera’ or ‘Qabu’ K. Kitchen, ‘Matbakh’ O. Oven S. Stores W. Bathroom, ‘Marhad’ or ‘Baet Al-mai’ Well, ‘be’er’

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Location and context The village is located in a semi-urban area 16 km east of Aleppo, between the highway that connects Aleppo to Al Bab and the base of a hill. A few kilometres from other villages, it is mostly surrounded by agricultural areas. Built approximately 250 years ago, there originally numbered 400 domes. It was probably built on or near an ancient Byzantine site, given the number of reused carved blocks in the buildings. It was around 1975 that the decline of the old dome village began. The proximity of the city, the attraction of modernity and the arrival of new industrial materials on the market, have encouraged people to convert or abandon their original homes. Some have voluntarily destroyed domes and rebuilt cement houses in the same place retaining similar functions, while others have included former domes into the composition of their new unit and have used them for animals or storage. Today, about a third of the villagers have moved to Aleppo, a third have constructed concrete houses in the neighbourhood, and the remaining third have settled in the modern village located at the western and northern side of the former village, whereas the southern and eastern parts have changed little or not at all. The village has two public buildings. The current mosque was built around 1975 on the site of the first building converted into a place of worship, which consists of two domes. The square of the mosque is the main gathering place. Another is being built on the hills east of the village. The school was first located in an uninhabited dome in 1956, catering also for children from other towns. Due to growing attendance, it was moved to a traditional unoccupied unit. Later, a school made of modern cement blocks, composed

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Tayara

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Population A mainly Arabic population of elderly, women and young children live in the village from day to day. The villagers survive principally on sheep farming and on agriculture but most of the time this is barely sufficient to support their large families. Some people also grow extra vegetables on their land outside the village. The products from livestock are dealt with by the women, who continue to make cheese, yogurt and butter. It is not uncommon for heads of families who have little land or animals to work for several days outside the village. A number of people go to town to live; they either stay for good or temporarily, which explains the small number of men and small number of young people in the village, having chosen instead to settle in town for work or study. Urban structure morphology This village is a rather dense, clustered habitat. It is divided into numerous housing units, which form large sectors or quarters when grouped together. The structural organization of the old village has been well planned with the exception of a few added housing units of spontaneous character. Today the village is divided into three distinct parts. The old part to the south is where the majority of domes is located, most are now in ruins or used as annexes to the main dwellings. To the south of this area only a few scatted modern buildings are to be found. The centre of the village is composed of mixed constructions. Old domes are combined with modern housing as a result of the development of the village in the ancient tradition, especially to the north and along the road to the west. A more recent part to the north has exclusively modern constructions. In the old village we can count about forty units, each of which has it own particular size and shape. Whether these entities are placed side by side or interlinked at times, they are composed of a variable number of buildings, the typology of which differs. They may have from one to eight domes along with several flat-roofed quadrangular constructions. They are enclosed and are organized around a courtyard with a mastaba and well. The modern part is composed of about fifty housing units. Their sizes and shapes are equally variable. They are either placed side by side or slightly interlinked or even isolated. They are com-

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of several small separate buildings, was built at the entrance to the village. Nine teachers work there.

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posed of one or several main blocks generally grouped in one part of the unit. Nowadays the unit is surrounded by walls, and no longer by the frame of the building. Here only one typology is to be found, the quadrangular building with one or two materials: stone and cement perpend. The space designated for the kitchen is now part of the main body of the building; it is the same for the toilets, which often adjoin the building. The mastaba and the well (internal or external to the unit) are always part of these contemporary constructions. Fruit trees can be found within the inhabited units, and some orchards are cultivated in the outskirts. Circulation The main street leading from the highway to the west of the village provides principle access, leading around the old village to the south and the new village to the northwest. In the old village, the roads have changed due to expansion and construction developments; the decline of certain parts has changed the original purpose of these roads. Narrow and winding, they make their way through the different units essentially oriented east-west. Another road goes through the village from north to south; from a steep street in the south, it levels off in the modern part of the village. In this area, the roads are wide and straight, lined with very high walls made of cement blocks or stone. We notice a main street leading into the zone and also some alleys and cul-de-sacs. In the old village, the entrance to the units is directly from the alleys, which is not always the case in the modern part with an increase in the number of dead-ends leading from the main roads. On the other hand, in the past the enclosed structure of the units was conceived as a protection against outsiders, whilst maintaining communication with the neighbourhood. Nowadays, the enclosed nature of the access to the habitations leaves no possibility of visual or oral communication. Wastewater flows freely down the street. Frequently, an open-air channel has been dug in the middle of the street to which households may link up via small gutters leading through the walls of inhabited units. Water supply Modernity has brought pumps for the wells and made irrigation easier. Water supply is still often problematic after winters of low rainfall, when wells dry up and water has to be bought. Though there are a great deal of water

holes in the village, the majority of old wells have dried up or have not been well maintained. Until 1980, water was in plentiful supply and the villagers dug wells of up to 40 to 50 metres. Nowadays, the villagers have no tap water and still use mechanically dug private wells with pumps and sometimes large reservoirs. The one main collective well is situated near the existing mosque. Construction technology in use. The dome still shows a perimeter base of roughly cut limestone, the height of which varies but does not generally exceed 60 cm. The dome rests on the base and the transition from the quadrangular to the circular plan is achieved with stone, wood or simply adobe elements situated in each corner, from where the pendentives begin. Sometimes the dome is enclosed by an external adobe wall, the height of which does not exceed 2 metres. Architectural morphology: a dwelling unit. This traditional unit, nowadays completely abandoned, is one of the most interesting in the locality since it is representative of the majority of the elements found dispersed around the village. Situated on the corner of two alleyways, it was built in several stages as and when the family grew larger. The unit consists partly of some flat-roofed quadrangular buildings, of which the facings and freestone openings are remarkable, and partly of two groups of three domes, two of which communicate with one another through a stone arch. These domes show all the details listed in the villageâ&#x20AC;&#x2122;s repertoire: niches of variable size and shape, airings, dĂŠcor, interior arrangements, stone and wooden steps, etc. The rooms of habitation are to be found in the domes and in the quadrangular buildings. The pair of domes to the east, which communicate through the well-constructed arch, were the original dwelling places with an adjoining food store. This unit in turn communicates also with the one behind, since it was later occupied by a member of the same family. The two northern rectangular buildings were built later for the offspring and their families, whilst the three western domes were designated for cooking, storage, fodder and animals. In the large courtyard we can see an oven and a well. Today, the floor and the plinths of the twin domes to the east are covered with cement, owing to the fact that these units were some of the last to be abandoned and were therefore modernized during the last phase of occupation.

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D. Dwelling house H. Stables, ‘Hazera’ or ‘Qabu’ K. Kitchen, ‘Matbakh’ S. Stores Well, ‘be’er’

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Joub Maadi

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Location and context Located southeast of Aleppo, this small village is located near Lake alAssad. It is divided in two by a road, beside which stands the mosque and many modern buildings. Population The population of this village remains consistent, particularly because of the proximity of a major road network that facilitates specific activities outside the village. The majority of people depend on livestock and agriculture for their living. Urban structure morphology The village straddles the road. The housing units have grown up in a row along this road and the village is consequently not very large. The majority of housing units are open and by the arrangement of buildings a more private courtyard space is sometimes created, and in some cases a small wall may also be used. Circulation The contiguous presence of a main road allows easy access along the entire length of the village. There is no real street within and the highways and footpaths are generally one and the same. Architectural morphology Domes in the village are of the simple dome type. However, these domes

are ‘truncated’ and ‘levelled off’ at construction. Although they are well built, it seems that the expertise is not as developed as in the area south of Aleppo, near Lake Jaboul. Here groups of domes are rare and not in more than three rows of four. On the other hand, the mixed typological domes and angled flat-roofed buildings are very sturdy and are often coated with lime. We can note the importance in this town of outside activities leading to the significant presence of mastaba, the small raised terraces, in each dwelling unit.

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D. Dwelling house O. Oven S. Stores T. Terrace, â&#x20AC;&#x2DC;Mastabaâ&#x20AC;&#x2122;

N 01

5 Earth Earth dome Earth flat roof

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Rasm Al Bugher

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Location and context This isolated village lies in the inland region of Lake al-Assad. Its size is relatively large, as is its population. Most of the water used comes from a secondary channel of the Euphrates, although some people also have private wells. Population Hailing from the tribe Ashira, residents built the village just over 200 years ago, when many families divided between Hama and Raqqa came together. Today, about 5,000 thousand people live in this village, although many travel regularly to Damascus to work. The inhabitants live mainly from livestock, which often leads them to the shores of the lake where they perform menial work in the plantations in exchange for the necessary fodder to feed their animals. Crops are grown mainly for their own consumption, although they sometimes sell the surplus at market. The school provides education up to the ninth grade, after which it is rare that girls continue their studies. The women concern themselves with the chores at home, while the men look after the animals and work the fields. Urban structure morphology This large village has an urban structure with relatively organized private spaces and numerous large public areas. As can be seen frequently, the most modern parts, built in cement, are located on the outskirts of the village. Units are closed in upon themselves, both by the arrangement of buildings and the use of high or low walls. Private gardens and growing spaces within the units are frequent.

Circulation Streets are numerous in the village since it is more or less concentric, though it is actually the space between buildings that allows circulation rather than premeditated thoroughfares. Many paths lead to the heart of town and cars and pedestrians use the same routes. There are virtually no pedestrian paths. Architectural morphology As in the village of Joub Maadi in the same area, the dome type in Rasm al Bugher is the single dome, present only in the ‘truncated‘ or ‘levelled’ form in which they were constructed. The technical quality of construction is less elaborate and has fewer architectural details. The flat-roofed buildings are also more prevalent than in other villages, and here buildings with quadrangular flat roofs predominate. It is to be noted that in this town the majority of buildings are coated with lime.

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N 01

Earth Earth dome Earth flat roof Earth and stones

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440

Couples et habitat

Location and context Cheikh Hilal, relatively far from Aleppo, is on roughly the same latitude as the city of Hama. Located at the meeting of fertile land and the eastern desert, it represents both the culture of the desert and the agricultural lifestyle. Its size is consistent and its current expansion is facilitated by the development of a highway network that runs alongside. There are no apparent rivers and but an irrigation system has been laid in place for crops. Population The population of this village is relatively large, although a number of people regularly travel to the nearby major cities to work. As in many villages, the population fluctuates with the seasons, since agriculture is the main source of livelihood. The village has a school and a mosque. Urban structure morphology Access to the village is from the main road located to the south, which divides into three secondary roads. One forms a central north/south route through the town, and on both sides of it well-defined quadrangular â&#x20AC;&#x2DC;sectorsâ&#x20AC;&#x2122; have developed. Indeed, even in areas which are not built on, these sectors are clearly visible. As often, the most modern areas are located on the outskirts of town, but it is difficult to distinguish here the heart of the old town, usually identified by the combination of highly agglomerated units. In this case, the units are distributed within the sectors, between six and ten per sector, roughly quadrangular, often detailed and mostly closed in on themselves. This arrangement is valid for the whole village, though we can find a minority of abandoned units with ruined domes.

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Cheikh Hilal

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scale 1:3000

Circulation The roads are numerous, large and oriented on a north-south and eastwest grid. Three secondary roads give access to the village: the first provides access to the town and divides it down the centre; a second comes in from the west and a third from the east, branching off toward the north. Here the roads are well constructed and spontaneous pedestrian pathways are virtually nonexistent even in the more densely populated areas. However, in the more built-up quadrangular sectors there are numerous makeshift streets and pedestrians paths.

Architectural morphology The simple dome type is predominant in the village, with the peculiarity that the perimeter base in very low. The dome starts on a square at ground level and seamlessly passes to the circular. The domes are well built and each has several stone steps, allowing access for re-plastering. They also have mostly a stone ‘tantour’ at the top. A special feature of this village is the large number of ‘truncated’ or ‘levelled’ domes, therefore suggesting a lack of dome repair work. This could also be due to the insertion of a half-height flat roof, or to the tendency to facilitate the completion of the job. We can also see the presence of reused ancient blocks in a number of buildings, most likely originating from the small mound located in the village.

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Vegetation has a notable presence with many trees within the units, as is also the case in the surroundings of the village.

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CONSERVATION OF CORBELLED DOME ARCHITECTURES

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The conservation of corbelled dome buildings has always been part of a natural process developed over the decades by the population of northeast Syria, who have passed from generation to generation the tacit knowledge associated with the practice of construction of buildings and regular maintenance, in order to prolong their useful life. Practices such as the remaking of the plaster coating every year after the rainy season, or making sure that capillary moisture or any kind of infiltration does not affect the walls built of earthen bricks, have been for many decades part of the natural process of maintenance. If this process is interrupted for any reason (because of cultural and/or technical factors), then the building falls into a progressive state of degradation, which could be stopped only if maintenance is carried out in time, because the earthen material is particularly vulnerable to the degradation produced by certain environmental agents. The collapse of a portion of walls, for example, can cause the collapse of the whole building, and the rain water that infiltrates from this failure can reduce the resistance of the material. Nowadays, corbelled dome houses, are in different states of conservation depending on the village: in those where people live and still have a strong care for the maintenance of the houses, they are in good condition; in those where the population has begun a process of migration, and there is no longer an emotional link with the buildings, they begin to deteriorate gradually; abandonment is, therefore, the primary agent of degradation.

University of Florence, Italy

The conservation and/or restoration practices to suggest here are limited so as to replicate traditional maintenance practices, respecting the construction techniques and original materials, to determine, in a few cases, recommendations for the improvement of the earthen material (stabilization), only if this improvement can be practiced by the local community who will ultimately be responsible for maintenance. Main degradation factors The cultural factors The corbelled dome buildings in the north of Syria, as seen in previous chapters, represent an adaptation process from the nomadic to the sedentary lifestyle, and therefore from sporadic habitation to permanent house, keeping the concept of a space suitable just for the satisfaction of basic needs (sleeping and cooking). Nowadays, the villages studied are subject of a new process of adaptation: the advent of modernity has led, on the one hand, to the migration of populations towards the city, and hence the abandonment of the domes, and on the other hand, to the emergence of new constructions with types and techniques that do not comply with the originals, which are gradually changing the character of the villages. Most types of deterioration in the corbelled dome buildings are the result of this gradual process of abandonment and lack of care. This phenomenon is increasing because of a disinclination of the inhabitants to value the heritage that this singular architecture represents. So, the first step to stopping

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Criteria for the conservation and restoration of corbelled dome architecture

Letizia Dipasquale Natalia Jorquera Silva

structions have lower mechanical performances (in terms of strength and stiffness), which can promote the development of certain types of pathologies. Earthen constructions also differ from brick masonry substantially for an especial sensitivity to the effects of water: the water runs down the wall or goes up through capillary moisture, which, if not checked, can produce numerous pathological effects. Since the earth is essentially an inconsistent material, it can take on several states depending on the water content. Water is an essential element at the moment of the mixture performed for the construction of earthen bricks, but once the material is dried and it behaves as a monolithic entity, the presence of moisture in the structure may cause the brick to return to its plastic state, with the consequent loss of mechanical properties such as strength and stiffness. Particular attention should be directed to the solutions that ensure the protection of buildings from rain, capillary humidity and any type of infiltration.

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the abandonment and the deterioration process, must be made from a reflection on the possible adaptation of these spaces to the contemporary needs of the inhabitants. The technical factors The corbelled dome structure, from a geometric point of view, is perfectly stable, and as mentioned before, if it is well made, it seems an excellent solution both from constructive and functional aspects; its weakness is the material vulnerability (the earth) to environmental actions, which increases if the dome is subject to a lack of regular and careful maintenance. Pathologies analysis in the corbelled dome building The different degradation forms that characterize the Syrian domed buildings, respond to the weaknesses related to the intrinsic characteristics of the material earth, and to the mechanical behaviour of masonry construction. The static principles that the earthen bricks system is based on, are the same as for the simple masonry construction: the structural elements (walls) work in compression, the statical behaviour is guaranteed by a correct geometry that ensures the equilibrium, and the material works within certain strength limits. However, unlike the construction of stone or brick masonry, earthen con-

The pathological manifestations The pathological manifestations of earthen dome constructions, many of which are detectable on earthen construction in general, but also in stone or brick masonry buildings, can be grouped into three main categories:

I â&#x20AC;&#x201C; Superficial material alteration of physical-chemical-biological nature - damp Stains; - superficial cracks; - rendering bubbling; - rendering flaking; - fungi; - moulds; - weed vegetation; - mosses and lichens. Belonging to this category are all the pathologies that alter the physicalchemical state of the material, without causing its loss. It is not difficult A

A,B,C: Damp Stains, D. Rendering bubbling and superficial cracks, E: superficial cracks, F, G: Rendering flaking, H: Weed vegetation, I: Mosses and lichens

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to take action against them to limit and repair the damage, but if they are not controlled, these pathologies can cause the appearance of more serious forms of degradation. The presence of material superficial alterations is in fact the first symptom of an action, intrinsic or extrinsic to the construction, that can be harmful to the building. For this reason, as well as curing the pathological event, it is necessary to understand and act on the cause that produced it. These alterations are usually due to environmental factors (rain, presence of moisture, presence of biological organisms, etc.), to the wrong use of the building, or to deficient maintenance.

II â&#x20AC;&#x201C;Material leak alteration - washing away; - erosion; - fall and leaking of elements. In this category, we find the pathologies that induce a removal of material from the surface. The construction element that shows these kinds

of symptoms has little cohesive property in its most degraded area; as a result of this, a removal from abrasion and crushing or a lifting followed by the flaking of one or more superficial layers can be originated. These kinds of pathologies are caused by processes of different natures and can produce some repercussions for the stability of the structure, in the case where a resistant portion of a construction element may be reduced. In the earthen domes of Syria, these phenomena are located predominantly at the base or at the corners of the walls; at the base is a symptom of poor drainage and stagnant water, which causes capillary moisture with a further disintegration of the affected portion. In cases where the loss of material is largely present on the walls, it is the result of prolonged exposure to the elements (rain and wind). A

A, B: Washing away and erosion, C, D: Erosion, E, F, G, H, I: Fall and leak of elements

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III â&#x20AC;&#x201C; Deep material alteration (physical-mechanical origin) deep fissures and lesions; - wall swelling; - collapse of portions; - ground subsidence. This type of pathology affects the structural behaviour of the building. As a result of this, the first consequence is the loss of continuity among the elements of construction, and a reduction in the resistance of the individual elements. The possible causes of these failures are: - a poor connection between the dome and the box wall, from which discontinuities and flaking can be created; - weakness in the connection where two walls meet at right angles; - failure of the basement, due to small movements of the individual earthen bricks. It is important to say, that any kind of pathological event may remain isolated or, in case of non-intervention, may generate new degenerative processes on the individual components and / or on the whole structure. The factors that determine the pathological manifestations on earthen structures are many and concatenated; to be able to guide the choice of an intervention at the root of the problem, and not just to deal with the symptom, we must act with a careful analysis and a deep knowledge of the factors that may cause damage to the buildings.

Interventions for improvement and repairing of damaged elements The interventions for improvement and repairing the damaged earthen dome elements will aim to slow the most frequent alteration processes: the partial or total loss of the plaster rendering, the subsidence of certain portions of the wall, and the presence of deep fissures (both in the corners where two walls meet at right angles, and in the discharging arc created under the tax line of the dome). The three main act of intervention are: - improvement or remake of the existing plaster coating, in order to delay maintenance, for protecting the internal structure of the walls from water and other erosive environmental factors; - improvement of the weakest structural parts of the construction (the foundations and connection of perpendicular walls); - improvement of the drainage water system, in order to remove moisture from the walls and protect the coating and the earthen material.

A, B, C: Deep fissures and lesions D, E, F: Portions collapse, g. Ground subsidence H, I: Wall swelling and portion collapse

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Introduction to the pathology treatment data sheets Globally speaking, the problems associated with the ageing of the earthen domes are mostly due to: - a lack of up-keeping: These traditional homes are often abandoned in favour of modern cement buildings; - water: mechanical erosion caused by running water, surface tension of water soluble crystallised salts that are transported by capillary action. The excess water in unfired earth masonry lowers the buildings resistance to compression and causes settlement and cracking. The pathologies, due to building method or that are linked to the shape and materials used, are: - masonry comprised of a mixture of unfired earth bricks and rubble stones results in a differential creeping between the two kinds of masonry; - settlement effects the bricks and the joints in earth masonry; only the joints are affected in stone masonry; - the difference in creeping creates a vertical crack between the two kinds of brick. Inclined forces are transferred by the domes. These forces may deform or break the masonry if the pendentive solution cannot support such actions or when the trust line goes out from vertical walls. Such responses are always conditioned by the brickwork quality. In these cases and where the settlement caused by water results in damage such as blistering, cracks running more or less vertically until the building finishes by collapsing. Despite the simplicity of the domes, a preliminary diagnostic should always be made before any repair work is carried out.

Ă&#x2C6;cole dâ&#x20AC;&#x2122;Avignon, France

Regular up-keeping, improvements in plaster and hydrated lime techniques, strengthening by the addition of woven strips of organic matter would all be technical improvements that would ease the task of general maintenance. The economic impact seems negligible given the advantages, but this would need looking at in finer detail. Hydrated lime, sand, fibres, as well as the quantities and method would need to be looked at with the local craftsmen so as to further fine-tune this advice. Additives to the mortar, choice of organic strip fibres each create a new direction to work in. These data sheets present a means of repairing the various damage incurred by the building that can be adapted to take into account traditional methods, the new materials found locally particularly with respect to hydrated lime. type of alteration

pathology

interventions

damp stains

1. 2.

superficial cracks plaster bubbling i. superficial material alteration

plaster flaking

cleaning and preparing the wall plaster remaking and improvement â&#x20AC;&#x201C; basis and finishing layer interior finishing remaking

fungi molds weed vegetation mosses and lichens washing away

ii. material leak

erosion

4. 5.

rebuiding part of the wall protecting the top of the dome base wall

repairing deep fissures and lesions repairing wall angles foundations reinforcement basement stone reinforcement

fall and leakof elements iii. deep material alteration (physicalmechanical origin)

deep fissures and lesions wall swelling portions collapse ground subsidences

7. 8. 9.

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Recommendations for technical conservation

Patrice Morot-Sir Jean Jacques Algros

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TS1 â&#x20AC;&#x201C; Cleaning and preparing the wall The way in which a surface is treated depends upon the state of the surface and the kind of damage observed. There are two ways of cleaning organic pollution: First method: mechanical removal of organic pollution by brushing In principal brushing is the most direct and also the easiest solution. This method does however have two inconveniences: it leaves marks which contribute to the rapid re-growth of organic pollution and more importantly it may further damage the masonry facing by removing part of the earth plaster. Cleaning is the easiest solution when it comes to regular up-keeping. Restore the original masonry and earth plaster if necessary (see data sheets F2 and F3 Plaster â&#x20AC;&#x201C; redoing and improving). Second Method: use of lime wash to destroy organic pollution Lime is highly alkaline and has a disinfecting action on the surface. It is better to start removing the organic matter mechanically before killing it with lime-wash. The surface to be treated should be clean. The area should be dampened before being coated with the lime wash. Before use, hydrated lime may come as slaked lime and may be in the form of a putty or a dry powder.

With quick lime the lime must be allowed to hydrate by being soaked in 3 times its own volume of water. The mixture must be allowed to cool before being used. It is applied either by being painted on with a brush or by projection. With a putty, the lime must first be mixed in water to give the required consistency. It can then be applied either by being painted on with a brush or by projection. Hydrated lime in powder form must be soaked in twice its own volume of water. It can then be applied either by being painted on with a brush or by projection. The plaster must be completely covered with a coat of whitewash (hydrated lime diluted in water). It can then be applied either by being painted on with a brush or by projection. The lime will successfully remove the pollution because of its strong alkaline pH value. Caution! Hydrated lime is used for this very same reason to treat the trunks of olive and fruit trees in Syria. Hydrated lime is highly alkaline. The alkalinity attacks organic pollutants. The product should be stored out of the reach of children. Avoid all contact with eyes and skin. In case of contact with eyes, rinse thoroughly with water. Lime-washing an external earthen plaster is an excellent way of protecting its surface against destruction caused by rain water.

A partial or full repair of the dome damaged exterior earth plaster is to be carried out. This is part of the necessary maintenance work to the domes. Plaster is the necessary protection against damage linked to the ageing of the building and is of the utmost importance for the parts of the building that are the most exposed. In the case of small disorders such as the development of organic matter (damp stains, fungi, moulds, weed vegetation, mosses and lichens), cleaning or cleaning and the application of a clay based paint or even better a lime based paint are quite sufficient solutions. In the case of larger problems (superficial cracks, blistering plaster, flaking plaster), it is important that the areas to be cleaned and rebuilt be defined as per the same techniques as for a complete rebuild. The earthen plaster is generally applied during the season when the earth is damp or at least when mixing water is available, at the coolest time of day by a skilled worker or by the owners themselves. Preparation of the earth mortar The materials used are generally those available close to the building. The earth is first sieved so as to remove all stones which would lead to the mortar being too thick. The mixture is made of clay based earth (not fertile or silt-laden earth), water, vegetation which should be pliable (hay) rather than rigid (straw) and perhaps even a fresh cow pat. The ingredients are trampled by foot to give an even mixture. Too much water will make the mortar shrink and too little will impair adhesion to the support. Applying earth plaster Before applying the mortar, the surface is cleaned, all debris removed and dampened. By dampening the support, the water in the mortar will not be absorbed too quickly which would otherwise result in the plaster cracking. Coat the surface with the earthen mortar. Start at the top of the domes and work down vertically to the foot of the masonry, avoiding all exposure to the sun. If the base course is made of rubble masonry, this is generally left un-rendered. The mortar is often applied by projection, balls of earth are placed next to each other which are then spread out by hand or with a trowel. The plaster is made up of two coats of earth: the first layer which is 2 cm

thick is not smoothed over so as to help the second layer to adhere. This second layer is smoothed over and is only 1 cm thick. The domes’ plaster is subjected to more rain erosion than the vertical walls. The thickness of this plaster should therefore be thicker: about 5 cm. The earth plaster is then covered with a coat of clay paint which should be as white as possible. The whiter the finish, the more light it will reflect resulting in lower interior temperatures during the summer. Caution! The earthen plaster on the outside of the domes could easily be replaced by a hydrated lime plaster. The yearly maintenance of the dome surfaces is one of the building’s inconveniences that has led to this kind of traditional dwelling being abandoned over time. It is particularly true of the domes and of the upper and horizontal parts of the vertical masonry corners where water often quickly finds a way to infiltrate causing damage. The hydrated lime plaster when well prepared and applied under good conditions is capable of resisting over a period of several years. It is kept in good condition with a coat of lime paint. The white clay or kaolin paint could be replaced by milk of lime. Both lime layers are stable to water, more resistant to pressure, antiseptic whilst remaining compatible with the physical-chemical characteristics of earthen masonry. The material is more expensive (not always available locally), it’s application could require a qualified craftsman, but users can do it by themselves after a light training.

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TS2 – Remaking and improving plaster – base and finishing layer

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TS3 – Restoration of interior finishing Generally a partial repair of the domes exterior earthen plaster and interior painting is carried out. This is part of the general up-keeping to the domes. When damage is slight as in the case of the development of organic matter (damp stains,fungi, moulds, weed vegetation, mosses and lichens), cleaning alone or cleaning and a coat of lime-wash suffice. When the problem is greater (superficial cracks, blistering plaster, flaking plaster), the areas to be cleaned and restored need to be determined in the same way as for a total repair. The earthen plaster can be carried out in the summer by skilled workers or by the owners themselves. Preparation of the earth mortar The materials used are generally those available close to the building. The earth is first sieved so as to remove all stones which would lead to the mortar being too thick. The mixture is made of clay based earth, water, vegetation which should be pliable (hay) rather than rigid (straw) and perhaps even a fresh cow pat. The ingredients are trampled by foot in a pit to give an even mixture. Too much water makes the mortar shrink and too little impairs adhesion to the support. Applying earthen plaster Before applying the mortar, the surface is cleaned, all debris removed and dampened. By dampening the support, the water in the mortar will not be absorbed too quickly which would other wise result in the mortar cracking. The mortar is often applied by projection, balls of earth placed next to each other which are then spread out by hand or with a trowel. The coating is smoothed over: leaving a 2 cm thick covering. The earthen plaster is then covered with a coat of clay paint which should be as white as possible. The whiter the finish the more light it will reflect. Caution! The earthen plaster inside the domes could be replaced by a hydrated lime plaster. The white clay or kaolin paint could be replaced by milk of lime. Both lime layers are stable to water, more resistant to pressure, antiseptic whilst remaining compatible with the physical-chemical characteristics of earthen masonry. The material is more expensive (not always available locally), it’s application could require a qualified craftsman, but users can do it by themselves after a light training.

TS4 – Rebuilding a part of a wall In practice, it is possible to identify pathologies in unbaked earth brick masonry of varying magnitude: on the surface, at depth, partial destruction to the thickness of the stone work. The latter is going to be the subject of this data sheet. The work must be carried out if possible during a period when the earth is damp without a forecast of rain: preferably during the spring. There must a way of propping up the damaged parts of the building during the repair works: tools to distribute pressure and rope and slings pulled taught for the domes’ horizontal base; the kind and amount of props necessary for containing the vertical forces. In the case of damage caused by settlement, rain water run-off water or ground splash, the areas to be treated need to be identified before the affected areas are cleared. Very partial damage For the repair of damage and/or the partial replacement of the masonry, once the protective props have been installed, the steps to carry out are as follows: - make the bricks and allow them to dry; - remove the earth plaster from the wall surface using a small pick axe; - remove the damaged earth bricks by hand or with the pick axe. The base of the part to be filled must be flat for the next course of bricks, it can slope inwards but never outwards. A rounded tail to the brick is better than parallel sides: always force toothing between old and new masonry. - prepare a clay earthen mortar and (for info 80% earth, 20% straw and water) and mix to the required consistency. To make the mortar, make a pit in the ground and use it as a work surface. - mix all the ingredients together. - replace the removed bricks with the new bricks. - Embed the new bricks with the pre-prepared mortar. - cover the surface of the new masonry with an earth plaster (see appropriate data sheet) In the case of minor damage, an easier alternative would be to fill the spaces left by the damaged stonework with earth mortar mixed with straw. Major damage The deterioration and the sagging of large parts of unbaked earth masonry are mainly due to water infiltration and the differential settlement of the corners after the dome is left without any maintenance. The damage can de

TS5 â&#x20AC;&#x201C; Protecting the top of the domes base wall with lime plaster Most of the damage to the domes is caused by the infiltration of water into the earth masonry. Too much water reduces the earth masonryâ&#x20AC;&#x2122;s resistance to compression. An inefficiency to resist compression results in creeping, sagging and the opening of cracks which eventually lead to the collapse of the building. So as to reduce the amount of necessary maintenance and the speed of the damage caused by the mechanical wear of water, it would be wise to replace the earth plaster to the horizontal surfaces with a lime plaster that is not affected by water. Preparation The surface of the horizontal tops to the vertical stonework are cleaned and all the earth plaster removed. These surfaces must be continued by a groove, a few centimeters long, made under the base of the domes to make it easier to do the waterproof joint. At the joint with the vertical walls, the plaster can be removed up to a height that must be established. Making the mortar The hydrated lime (in the form of putty, powder or natural hydraulic powdered lime) are the mineral binders that work best with earth masonry. Cement is too hard and not permeable enough to water vapour for the kind of plaster required for this kind of earth masonry. The required amounts and kinds of sand differs according to the course being work upon: - For the priming layer: coarse sand; quantities: about 1 volume of hydrated lime for 2 volumes of sand. This coat is given a rough surface. - For dressing: coarse sand; quantities: about 1 volume of hydrated lime for 2.5 volumes of sand. Make as thick as the existing plaster. - For the final finishing coat: fine sand; quantities: about 1 volume of hydrated lime for 3 volumes of sand. Application of a thin coat roughly 5 mm thick. Application Unlike with earthen plaster, lime plaster can not be worked by hand and a tool must be used because of itâ&#x20AC;&#x2122;s very aggressive pH levels for the skin and the mucous membranes. The plaster is applied by successive layers onto a surface that is dampened between each application. Both the priming and dressing layers must be roughly finished to enable the next coat to adhere.

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repaired by taking down a part of the wall or/and the domes and by rebuilding it. To do this, follow the instructions described above. The only difference with the method already described is the method of propping the collapsed part of the domes and the quantity of material and amount of work involved. Caution! As a priority, it is important to identify the cause of the damage before starting the repair work. This diagnosis is exceptionally important. Domes that are found in a damaged state due to being left abandoned. It is therefore mistaken to propose the repair of the building if it is not going to be used and maintained. In the case of large scale damage to the vertical walls, the temporary us of ropes around the domes is as necessary as the vertical wall props.

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The final finishing layer must be very thin (about 5 mm) so as to avoid cracking, and to be smooth like the finish to the earthen plaster. Details Lime plaster slopes away from the building. Lime mortar with sloping groove to exterior under the base of the domes to avoid a change in material as well as a possibility of water infiltrating vertically to the angle between the two rendered surfaces (angle between the domes and the horizontal flashing). The bottom part of the plaster must act as a drip: the lower part of the plaster must slope outwards. Caution! Hydrated lime is very alkaline: do not use hands to use this mortar. Avoid contact with eyes. Keep out of reach of children whilst in use. Cleaning and dampening the surface between each layer is essential to achieving a quality finish. The lime plaster should be prepared out of the sun, in low temperatures and on a damp surface. Applying fine coats to a rough base which has already been allowed to set and shrink is necessary to obtaining a final uncracked plaster. Allowing the plaster to take and shrink back between each coat reduces the chance of cracking.

TS6 â&#x20AC;&#x201C; Repairing deep cracks and damage Deep cracks and damage are the result of movement and a drop in strength due to penetration of water into the domes earthen masonry. The gaps created by the running cracks and damage allows for air to enter which reduces the comfort of the home. However when water enters the crack, it causes erosion and further damages the domes earthen masonry. Even if the repair of deep or running cracks is not a cure in itself against the original cause of the problem, it does stop water and air from further penetrating the masonry. This makes the home more comfortable and is a way of preventing damage from further evolving and the technique strengthens the building by sealing the damaged areas with vegetable fibres. Preparation and application of earth plaster over the cracks Repairing the damage by covering over the cracks with earthen plaster guarantees water tightness during the injection of the grouting. The earth is sieved to remove all stones which would hinder the use of the mortar in the space left available for the joints. The mixture is comprised of water and sieved earth to which short, pliable fibres can be added as well as an organic binder such as a cow pat. The mixture is then mixed by foot in a pit to give an even putty consistency. Too much water makes the mortar shrink and too little impairs adhesion to the support. Before applying the mortar, the surface is cleaned, all debris removed and dampened. By dampening the support, the water in the mortar will not be absorbed too quickly which would other wise result in the plaster cracking. Render the surface with the earthen mortar Start plaster at the bottom of the crack and work upwards, avoid direct sun. The mortar can be pushed into the crack as far as possible using a tool. Work in areas 50-80 cm high. This area is then injected with the grouting before repeating this step again. Preparation and injecting the earth grouting into the crack The earth is sieved to remove all large stones and give a granule size smaller or equal to 0-2 mm to make injecting easier. The grouting is made into a liquid with an oil-like consistency which is the result of the earth and water being excessively mixed avoiding the sediment from settling too quickly. Before grouting, water is injected into the crack to dampen it.

Caution! Filling the cracks in the domes masonry, whether they are running or not, will not result in the stonework being as solid as when it was in a good condition, particularly with regards the masonry resistance to compression. Depending on the actual individual crack, the repair work simply blocks the air from entering and water from penetrating. Repair work to the crack slows down the development of the pathologies in progress. Cement based mortars and grouting do not have the same physical characteristics making them incompatible with the domes earth based stonework: they are too hard and not porous enough. The organic material embedded into the stonework can be used to eliminate the horizontal force from the domes: in this case, the strips are embedded in continuous lines in circular cuts made at the base of the domes. The organic material can be embedded in masonry that is comprised of both rubble stone and unfired earth blocks. The organic material creates a binder between the stone work in the case of cracks appearing that are due to the different creep behaviour of the two kinds of masonry. The organic strips are then embedded in the cut outs made in the unbaked earth blocks and in the cut outs made in the joints of the stone masonry. The end of the strips can be fanned out and embedded perpendicular to the direction of the strips on the dressed surface to force toothing.

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Creating a swallows nest shape at the point of the injection will make the job easier. The grout is injected until the crack is full: the level of the groutingÂ is level with the top of the crack. Restart at the top part of the crack until no more grouting can be injected. Strengthening by adding organic fibres. The strengthening process is finally finished with the addition of organic fibres. Grooves are made into the unfired earthen masonry either side of the crack, 20 cm wide and deep and 50-80 cm long, vertically every 60 cm up the wall. The cuts can also be in the shape of an X, long and placed horizontally with the centre of the cross placed on the crack. The parts that are between the support ropes form connecting rods that work to assist with compression. The cut outs are cleaned and dampened before being filled so as to help adhesion and to lessen the chance of shrinkage when drying. The organic fibre strips are twisted and rolled in the earth which has had water added to it and become plastic like in consistency. The fibres can be flax or hemp tow or raphia depending on what is available locally. The strips are embedded in straight lines in the cut out. This is then filled with mortar and re-rendered to join flush with the existing plaster.

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TS7 â&#x20AC;&#x201C; Repairing wall corners The base corners of the domes are the parts of the dome that show the most damage no matter what the construction method used: rubble stone masonry with earth mortar pointing or unbaked earth bricks using the same pointing. The first phase is the deterioration of the earth plaster that is applied to protect both kinds of stonework and in particular the horizontal surfaces around the base of the domes. The second phase is the more or less swift and visible consequence of the penetration of water into the masonry and the pressure caused by the horizontal force created by the domesâ&#x20AC;&#x2122; weight on to the vertical rectangular base: blistering of rubble stone masonry, tilting forward of earth masonry with cracks that are more or less vertical at either side of the domesâ&#x20AC;&#x2122;corners. The third phase is the partial collapse of the domes corners and a part of the domes. The repair job is the rebuilding of the original masonry with the same materials and techniques as were initially used. It can then be finished with:

-a horizontal band of organic fibres at the base of domes (see drawing attached), - rainwater flashing between the domes and the horizontal part to the vertical masonry, - stapling of large vertical cracks when the wall has not yet collapsed. The preparation work for the two kinds of masonry is the same: encircling of the domes with ropes or slings with pressure distributors; vertical props for masonry work. Repair of the rubble stone masonry Building materials are generally used. The earth from the old mortar can also be reused. The earth is sieved to remove all stones which would hinder the use of the mortar in the space left available for the joints. The mixture is then mixed by foot to give a putty consistency to hold the bricks in place. The blocks are rebuilt respecting the height of the existing masonry. The blocks are placed in line and made to sit vertically, each course has crossed joints at mid-point to avoid the formation of a running joint. Under the domes, the last stone elements are forced in to help hold its base in place. Once the joint mortar is dry, the supports are removed and the holes that are left are filled. Repair of unfired earthen brick masonry. Generally the damaged masonry is reused to provide the material for the bricks and the earthen mortar. It is often necessary to add straw to the mud. Before starting the repair work, the damaged bricks are removed, the top face is made to lie horizontally, the surrounding areas are cleaned and dampened. By dampening the support, the water in the mortar will not be absorbed too quickly which would other wise result in the plaster cracking. The blocks are rebuilt respecting the height of the existing masonry. The blocks are placed in line and made to sit vertically, each course has crossed joints at mid-point along each stone to avoid the formation of a running joint. Under the domes, the last stone elements are forced in to help hold its base in place. Once the joint mortar is dry, the supports are removed and the holes that are left are filled. Coat the surface with the earthen mortar. Start at the top of the domes and work down vertically to the foot of the masonry and avoid all exposure to the sun. If the base course is made of rubble stone work, this is generally left un-rendered.

TS8 – Reinforcement of foundations When looking at the lower part of the domes, we do not see any foundations i.e. buried masonry. We do however often see several ground level causes of rubble stone: the role of these blocks is to give better resistance to downward forces, to ground splash water run-off, to the capillary transport of salt and all other damage caused by the presence of humidity. A brief study of the domes’ masonry shows that there is roughly 1 bar of pressure at ground level. This allows us to understand the reasoning behind the absence of a foundation layer. The reinforcement of foundations as demonstrated in techniques such as reinforced concrete, injection and other contemporary building techniques would not be appropriate for the domes. The buildings proportions were chosen so as to allow the use of techniques that could easily be carried out by the local workforce and therefore takes into account the fundamental characteristics of such constructions: earth stone work, building with one level resulting in a low ground level stress. Maintenance of lower stone work Slopes directed from the ground away from the building, water channels or other well thought out draining systems.

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Caution! As improvement in the building techniques the earthen plaster on the outside of the domes could easily be replaced by a hydrated lime plaster. The yearly maintenance of the domes’ surfaces is one of the buildings major inconveniences that has led to this kind of traditional dwelling being abandoned. It is particularly true of the domes and the upper and horizontal parts of the vertical masonry corners where water often quickly finds a way to infiltrate causing damage. Hydrated lime plaster is finally the best way of improving the construction techniques for building a domes. The hydrated lime plaster when well prepared and applied under good conditions is capable of resisting several years. It is looked after with a coat of lime paint. The white clay or kaolin paint could be replaced by milk of lime. Both lime layers are stable to water, more resistant to pressure, antiseptic whilst remaining compatible with the physical-chemical characteristics of earthen masonry. The material is more expensive (not always available locally), it’s application could require a qualified craftsman, but users can do it by themselves after a light training.

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TS9 â&#x20AC;&#x201C; Reinforcement of the stone base In buildings like the domes, it is the base of the building that is put under the most pressure from the height of the domes and the horizontal tops to the vertical walls. The rarity of ground-splash rainwater run-off, the capillary transport of water and the salt that it contains, shocks and other physical damage are the main causes of destruction to this masonry. The base course of the domes is made of either unfired earthen bricks or rubble stone masonry filled with smaller elements and earthen mortar. The main problem experienced when the base level of the domes is made of earthen bricks is the loss of material resulting in a thinning to the thickness of the wall. The main problem when the base level of the domes is made of rubble stone masonry is the loss of the protective plaster and the mortar pointing. The loss of the mortar binding material results in the masonry being badly held together, settlement leading to distortion, blistering and then the eventual collapse of the building.

Repair of rubble stone masonry Building materials are generally used. The earth from the old mortar can also be reused. The earth is sieved to remove all stones which would hinder the use of the mortar in the space left available for the joints. The mixture is then mixed by foot to give a putty consistency to hold the bricks in place. The blocks are rebuilt respecting the height of the existing masonry. The blocks are placed in line and made to sit vertically, each course has crossed joints at mid-point to avoid the formation of a running joint. Under the domes, the last stone elements are forced in to help hold the base in place. Once the pointing is dry, the supports are removed and the holes that are left are filled. Preparation of the earth mortar for the application of an earth-based plaster. The earth-based plaster is applied to cover the joint between the new masonry and the old masonry comprised of rubble stone and earth. See technical sheet TS2. Preparation and application of earth grouting The earth grouting is used everywhere where there may be a hole in the part of the masonry being treated. See technical sheet TS6. Repair of base masonry made of unbaked earth bricks. The repair of unbaked earth brick masonry is exactly as in the case shown in technical sheet TS7 for the same kind of unbaked earth brick masonry. The difference is the location of the repair to be carried out. The top face is always made horizontal so as to exert a vertical force on the masonry without any horizontal constituent. Caution! Lack of maintenance is always the origin of accelerated disorders and ageing. The lower parts of the building are particularly exposed to the capillary transport of water and the salt that it contains. The base on to which the first course of bricks is placed must be flat and horizontal. The height of the rubble stone and unbaked earth brick masonry must be exactly the same height as the original surrounding bricks: settlement and progressive movement vary depending on the materials used. The grout can only be injected once the masonry has been made watertight with a protective plaster layer. This is essential for when filling and binding the outer edges of the parts that have been repaired.

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Polytechnic University of Valencia, Spain

The problem of preserving Syrian beehive domes is no different from that of preserving vernacular architecture in the rest of the world. The traditional agricultural economy of subsistence in every context generated its own vernacular architecture based upon available means and materials. Pragmatism, functionality and immediacy in these buildings guaranteed their integration into the surrounding landscape. A panorama of the conservation of vernacular architecture in rural landscapes The arrival of industrialization or, at least, of motorized transport, has suddenly and brutally affected these idyllic vernacular milieus with the introduction of new materials and imported constructive systems. Above all, the new mentality rejects traditional constructions as being associated with the poverty and self-sufficiency of the past, and vehemently adopts imported architecture, regardless of whether or not it might integrate poorly into the surroundings or fail to adapt to the functional necessities of the area. Fresh technologies have doubtlessly come into vernacular architecture everywhere, but these changes would have taken place very gradually and the permanent use of local materials always guaranteed assimilation into the landscape. Nowadays, vernacular architecture is often directly destroyed or, at best, remains neglected and frequently without the customary maintenance that any building requires. The problem worsens when the specific materials and constructive techniques used in this vernacular architecture need frequent maintenance themselves, as is the case with Syrian beehive domes.

As in any other part of the world where vernacular architecture still survives changes in the traditional economy, in the case of the beehive domes the choice is presented between either: - conserving and restoring vernacular architecture independently of the disappearance of the social and economic context that once generated it; - or allowing change to take its course and consequently the gradual extinction of such architecture. If in the heart of the city there is generally an attitude towards the conserving and restoring of historic architecture as a physical testament to the material culture of the past, even if this culture no longer exists, the same logics of conservation and restoration ought to be applied to rural vernacular architecture in general and to Syrian beehive dome villages in particular. Biology teaches us that when a specimen stops breeding automatically it becomes an endangered species. It may then be stated that most of the worldâ&#x20AC;&#x2122;s vernacular architecture has become an endangered species, unable to reproduce, though it may surely be safeguarded and preserved. Where then, is the possible difference between the conservation and restoration of urban historic buildings and rural vernacular buildings? Why does it seem that vernacular architecture is much more difficult to preserve? There are several possible factors that may have an influence upon this. First of all, as happens with many urban historical dwellings, vernacular architecture has no monumental character, frequently no decoration and is modest in a building context. Its value lies in the materials and techniques employed that act as a constructed document or witness to history, and are

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Strategies and actions for the conservation of corbelled dome villages as urban and architectural landscape

Fernando Vegas Camilla Mileto

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proof of its capability to answer functionally with whatever means available, while at the same time integrating itself into the landscape. Such a nonmonumental condition represents in many cases a serious difficulty when it comes to protecting this type of architecture. Secondly, there are the social and economic problems linked to a general abandonment of rural farming, economic problems, lack of means to survive, ageing of the population and emigration toward big cities, factors which all tend to depopulate such rural villages. The result is a subsequent decline in care and maintenance of these magnificent examples of vernacular architecture and a gradual substitution with the new architecture of contemporaneous aesthetics and building systems that seriously impact the whole. Associated to this second factor one may add: the lack of protection and planning control that could preserve vernacular architecture; the mentality of unimpeded development typical of the remaining inhabitants in these villages, commonly identifying their old buildings with the hardships of the past and the new with social and economic progress; the fear of hindering any possible economic development of the local building industry with overly severe protecting regulations; and the uncertain promise of economic progress derived from inland tourism attracted by a well-preserved vernacular architecture and landscape. Actions to be implemented for the conservation of vernacular architecture in rural landscapes After various experiences over the last fifty years of the conservation and restoration of vernacular architecture around the world, the beneficial influence and even necessary implementation of the following actions can be confirmed: Maintenance, conservation and restoration works in vernacular architecture represent a preponderant economic investment in manpower, one that remains in the area of the restored building, while any new-built building represents a preponderant investment in newly-bought materials or machinery, both of which come from other cities or even other countries. That is to say that any investment in restoration is to the advantage of the development of the local economy through the work given to its craftsmen, artisans, carpenters, smiths and local small industries. Restoration of this architecture should employ local manpower as a means to revitalizing the local economy and maintaining building traditions. Nev-

Strategies for the conservation of vernacular architecture in rural landscapes As with any other example of vernacular architecture around the world, there exist two main ways of preserving these outstanding dwellings in Syria. Though not always possible or feasible, there could be proposed the implementation of protection, safeguard and restoration regulations and even economic subsidies for this type of architecture from local, regional or national governments. Such actions, rare enough even in developed coun-

tries where part of the economic surplus could be dedicated to the conservation of architectural heritage, are almost impossible to implement in as yet undeveloped countries such as Syria, where many other priorities exist. A second option, and surely even more efficient than the first, is the revaluation of vernacular architecture in the mentality of the countryâ&#x20AC;&#x2122;s inhabitants, as an identifying mark of national pride. Due to its intangibility, such an action may be more difficult to put into practice than issuing protection regulations or subsidies for restoration, but the effect is independent from the state, common among a great part of vernacular dwellings and is generally positive for preservation. This type of social action begins early on in education and requires long-term work with the population as a whole. Associated to these actions and not always well-directed, but always positive in some way from the point of view of the conservation of vernacular architecture in a specific place, may be the promotion of tourism in the area, mainly because of the distinctive and outstanding character given by its vernacular architecture and landscape. Tourism may both empty and transform the content, freeze and place the vernacular architecture in a museum, but if the risk is otherwise to lose these Syrian beehive dome dwellings completely, the end would justify the means. The diverse longevity of materials in vernacular architecture As has been mentioned, the differing longevity of the materials employed in vernacular architecture and the specific longevity of its combination and relative disposition in the building will determine to a large part the frequency of necessary maintenance for conservation. Longevity may be divided up into the following types: - Guaranteed longevity, when the durability of the material far surpasses a personâ&#x20AC;&#x2122;s life. For example, most of the stone and brick used in traditional architecture belongs to this type. There do exist very friable stones or halffired bricks and even very solid stones and bricks in difficult circumstances or under physical or chemical attacks that threaten this apparent durability, but in general terms it may be considered adequate to assign these materials to guaranteed longevity. - Conditioned or guarded longevity, when the durability of the material needs protection against atmospheric agents, or necessitates an amount of treatment, cleaning or maintenance. For example, the survival of a sun-dried brick or rammed earth wall does not depend much upon itself, but on the

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ertheless, in cases where it proves impossible to find specialized manpower because of the loss of vernacular building traditions, any manpower capable of interpreting and repairing existing buildings under the supervision of an architect should be well received before giving up the conservation of this vernacular architecture. If vernacular architecture is to be preserved and the impact of restoration is to be reduced to a minimum, differing materials and techniques may have to be employed. In the case of Syrian beehive dome dwellings this idea would imply, for example, the reparation or restoration of vaulted structures with sun-dried bricks and mud mortars similar to existing ones, or, if necessary, the implementation of compatible reinforcements, either vegetal (straw, wickerwork) or mineral (lime, gypsum), mixed with the traditional mud renderings that are customarily applied as part of building maintenance. Maintenance is a necessary and unavoidable condition for every type of building, whether traditional or modern. Vernacular architecture is hardly an exception to the rule and, therefore, maintenance must be taken into account. However, the longevity of materials employed in erecting traditional architecture determines the necessary rhythm of its maintenance. In this regard, we could make the following classifications: - vernacular architecture of ephemeral character (i.e. vegetal or thatched roofs, mud renderings), liable to continuous and short-term maintenance; - vernacular architecture of semi-durable character (i.e. exposed wood, tile or slate roof), liable to medium-term maintenance; - and vernacular architecture of lasting character (stone walls, corbelled stone domes), liable to long-term maintenance. The less maintenance vernacular architecture requires, the greater are its chances of survival. Syrian beehive dome dwellings belong to the vernacular architecture group of ephemeral character and this factor hinders their survival.

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presence and good state of its basement and eaves; the survival of the lime or gypsum renderings on stone walls or earthen walls depends mainly on the health of the wall and eaves; the durability of wood exposed to the elements needs some care, and the health of interior wood depends on good ventilation and low humidity; the survival of a tile or slate roof also needs modest but continuous efforts of maintenance and reparation. - Ephemeral longevity, when the inherent durability of the material is very short, such as a winter, a rainy season, an annual cycle or a period of a few years. For example, a thatched roof is liable to drying or rotting, while the durability of a shingle or turf roof, also ephemeral, will be longer; a mud rendering needs to be re-done continuously, probably every year. In fact, the mud renderings that cover buildings and domes built with sun-dried bricks in Mali, the survival of which depends on the health of the rendering, belong for example to this type. Therefore, we may say that the different types of longevity of materials are interlinked. For example, a Dogon granary, with thin walls and dome built and shaped with mud, has a guarded longevity owing to the thatched overhanging cover that protects both dome and walls, but the ephemeral longevity of the thatched covering may expose the mud building to risk quickly if not maintained. The Syrian beehive corbelled dome also represent an example of architecture of guarded longevity that depends chiefly on the ephemeral longevity of the mud rendering that needs continuous maintenance. In the absence of any maintenance and remaking of the mud rendering, a degenerative process begins mainly due to the rainwater that can completely ruin the building. Types of intervention in vernacular architecture of ephemeral character Every action of conservation may be considered maintenance if it is implemented with the same existing materials and techniques by the same inhabitants. We also may consider as maintenance the acts of substitution of ephemeral materials of vernacular architecture because, contrary to materials of guaranteed, guarded or conditioned longevity, this renovation is inherent to the materials themselves. In the case of ephemeral longevity, whatever the durability, acts of maintenance that mean the substitution of perishable materials are more important than the material value of the building itself, because its life and integrity depend on the periodic renovation of these ephemeral materials. In

this case, maintenance ought not previously to abandon the building to its fate, which would not take long since in the short term it would require such acts of maintenance. In the case of guarded or conditioned longevity, lack of care due to abandonment of the building is to be blamed for the malfunction of the material or architectural element. That is to say, the building abandons its customary function and remains void of content. Restoration comes in suddenly and traumatically to solve in a single stroke all the accumulated problems of the building resulting from the lack of care, even with the renovation of some materials or elements. For this reason, the best way to conserve vernacular architecture would be to implement customary acts of maintenance rather than to restore it. Restoration may also be carried out on a building of ephemeral longevity but this intervention will be increasingly traumatic as time passes following the abandonment of the building. On the contrary, in general terms, restoration is usually more feasible and reliable in its results when applied to materials and buildings of guaranteed longevity. In an extreme case, the reconstruction after the destruction or complete ruin of a building is viable, but this may have a symbolic or didactic character in the design, construction and re-use of the building rather than a restoration value as this action does not belong to the world of architectural conservation. If maintenance, either of a building with ephemeral materials or a building with guarded or conditioned longevity, includes the use of imported materials or techniques from outside the traditional architectural context in order to extend the life of the material or the whole building, even maintaining the same use, this would not be considered maintenance but restoration. An act of conservation involving transformation of use by external agents is also to be considered restoration. Therefore, acts of restoration usually add imported materials or techniques from outside the specific context due to three reasons: - to extend the life of the materials of the building; - to extend the life of the building itself, through additional protections; - to imitate the aspect or finishing of existing materials of the building. Restoration is always restoration, even if it uses exclusively traditional materials and techniques, considering that the attitude towards the building is completely different from simple maintenance that would renovate the ephemeral materials or attend to the materials of guarded or conditioned

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longevity. Restoration considers the building finished in itself, as an object to be preserved with the same use or a new one, frequently trying to recover both the structural integrity and the visual decorum and health of the building, whilst also upgrading associated infrastructures and fittings to contemporaneous standards. Restoration adopts an intellectualized attitude and a certain valuation of the building, while maintenance assumes a more uninhibited attitude that might be equivalent to cleaning a home, changing a plug or repairing a washing machine. In this case, functional value has priority. Adapting the building to new conditions and situations by the same inhabitants belongs to the same attitude, like setting up an aerial, renovating the plumbing or wiring, etc. We may also call this type of action maintenance. What halts then this fresh and uninhibited attitude typical of maintenance before restoration? The arrival of a person from an external context may find other values beyond functionality in the building. The inhabitants who live there do not necessary confer any conscious value on tradition. The value of history, memory, identity and tradition often reveals itself to people extraneous to the local context, it may also be the fruit of an infrequent sensibility of local inhabitants, or the result of destruction due to some kind of trauma, such as wars, natural disasters or a sudden industrial revolution that may put an end to craft and manual work, thus awakening a nostalgia for the past. In the case of Syrian beehive domes, being buildings of guarded longevity liable to materials of ephemeral longevity, such as mud rendering, it may be convenient to establish a protocol of maintenance that would oversee their survival. This maintenance could also be linked to a local festival, as happens with the mosques in Mali that are rendered every year with mud during the January festival, a perfect opportunity for maintenance. Restoring these dwellings is indeed possible, however, even employing traditional materials and techniques for repairs, attitudes would differ from a local inhabitant who would otherwise discard any reparation and rebuild the whole building. Restoration may and sometimes must resort to the reproduction or interpretation of local constructive techniques or even to the innovation of solutions in order to achieve maximum suitability and compatibility with the existing building.

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Index

FOREWORDS Foreword to Earthen Domes and Habitats of North Syria, a shared Heritage between East and West John Hurd

8 11

In Syria: earthen architecture, mother architecture Michel Al-Maqdisi

Corbelled earthen dome villages of Syria: from past to sunstainable future Saverio Mecca

An important new contribution to Syrian architectural heritage Abd Al-Qader Hariri

Coupoles et habitats,an EU Culture 2000 project Alexis Castro, Saverio Mecca

Vernacular architecture as a cultural heritage shared by East and West Vassilis Koniordos

ARCHAELOGY OF CORBELLED DOMES

The corbelled dome in the archaeology of the ancient Near East Ă&#x2013;nhan Tunca, Katrien Rutten

Prehistoric dome architecture in the Aegean Clairy Palyvou

Tholos tombs in Etruria Mario Cygielman

VERNACULAR CORBELLED DOME IN MEDITERRANEAN

Corbelling of the Mediterranean Borut Juvanec

Corbelled dome architecture in Spain and Portugal Fernando Vegas, Camilla Mileto, Valentina Cristini

Dry-stone buildings in Provence Patrice Morot-Sir

Corbelled dome architecture in Greece Maria Arakadaki

Corbelled dome architecture in Sardinia Silvia Onnis

111

Corbelled domes of Apulia (Italy) Letizia Dipasquale, Natalia Jorquera Silva

123

Garadam, corbelled dome architecture in Azerbaijan Sabina Hajiyeva, Saverio Mecca

143

478

AN INTERDISCIPLINARY METHOD

151

Earthen Domes and Habitats

An interdisciplinary approach to a cultural and architectural heritage Saverio Mecca, Natalia Jorquera Silva

153

Geomatic methods of surveying Grazia Tucci, Valentina Bonora, Alessia Nobile, Konstantinos Tokmakidis

157

Urban and architectural analysis Fernando Vegas,Camilla Mileto,Valentina Cristini, Letizia Dipasquale

163

Constructive analysis Saverio Mecca, Letizia Dipasquale, Natalia Jorquera Silva, Silvia Onnis, Patrice Morot-Sir, Jean-Jacques Algros

167

Structural analysis Mirta Paglini, Luisa Rovero, Ugo Tonietti, Adolfo Alonso Durรก

169

Archaeometrical analysis of earthen architectural materials Fabio Fratini

173

AN ARCHITECTURAL CULTURAL LANDSCAPE

177

An architectural culture of uncertainty Saverio Mecca

179

A geographical analysis: the regions of Aleppo and Central Syria Mohamed Al Dbiyat

187

Domestic earthen dome architecture of Central Syria Michel al-Maqdissi, Antoine Suleiman, Fadia Abou Sekeh

197

Earthen Domes in Northern Syria. Ar-Raqqah, Aleppo, Idlib Mohammed Dello, Saverio Mecca

215

Byzantine settlements and management of environmental resources in Central Syria: the case of the basalt uplands Nazir Awad, Marion Rivoal

227

Glossary of earthen architectural terms in Syria Mohammed Dello, Saverio Mecca

243

An architectural analysis

255

The urban morphology of dome villages Emmanuelle Devaux, Letizia Dipasquale

257

The architectural morphology of corbelled dome houses Letizia Dipasquale, Camilla Mileto & Fernando Vegas

267

Corbelled domes interiors: mobility and flexibility Giuseppe Lotti

287

Surveying and documenting corbelled dome architectures Grazia Tucci, Valentina Bonora, Alessia Nobile, Konstantinos Tokmakidis

297

313

Building culture of corbelled dome architecture Silvia Onnis, Letizia Dipasquale, Mirta Paglini

323

Constructive and structural analysis: identification of the structure Mirta Paglini, Luisa Rovero, Ugo Tonietti

353

Statical analysis of the earthen corbelled course domes Mirta Paglini, Luisa Rovero, Ugo Tonietti

363

The earthen in-scale model and the mechanical tests Dalia Omar Sidik, Mirta Paglini, Elena Peducci, Flavio Ridolfi, Luisa Rovero, Ugo Tonietti

369

A numerical no-tension code application for the dome structural analysis Adolfo Alonso Durá, Arturo Martínez Boquera, Verónica Llopis Pulido

379

TEN EARTHEN DOME VILLAGES OF NORTHERN SYRIA

383

Ten villages of Northern Syria Emmanuelle Devaux , Letizia Dipasquale

385

Oum Aamoud Kebir

387

Oum Aamoud Seghir

393

Rasm Hamd

399

Fejdane

407

Er Raheb

413

Rbaiaa

419

Tayara

425

Joub Maadi

433

Rasm Al Bougher

437

Cheikh Hilal

441

CONSERVATION OF CORBELLED DOME ARCHITECTURES

447

Criteria for the conservation and restoration of corbelled dome architecture

449

Letizia Dipasquale, Natalia Jorquera Silva 457

Recommendations for technical conservation

Patrice Morot-Sir, Jean Jacques Algros Strategies and actions for the conservation of corbelled dome villages as urban and architectural landscape

Camilla Mileto, Fernando Vegas

469

479

Earthen Domes and Habitats

The archaeometric analysis of building materials Fabio Fratini

Finito di stampare nel mese di novembre 2009 in Pisa dalle Edizioni ETS Piazza Carrara, 16-19, I-56126 Pisa info@edizioniets.com www.edizioniets.com

A heritage of exceptional value The interest for the study of domed habitats in the north of Syria is closely linked to this exceptional fluctuating culture of uncertainty. Throughout the centuries not only have sedentary peoples substituted nomadic tribes, but also the populations have fluctuated between the two lifestyles, often integrated and present in the same communities or even the same families. All the different peoples who have lived in these regions down the millennia have had to restrict their living and develop strategies to deal with climatic uncertainties, and chiefly with the supply and availability of clean drinking water. The arid climate has dominated the character of the region for millennia, a determining factor for settlement, architecture, building culture, use of land and various resources in relation to different kinds of topology, hydrology and geomorphology. This book synthesizes the results of the ‘Coupoles Et Habitats, Une tradition constructive entre Orient et Occident’ project, funded by EACEA of European Commission. The main result is to document the unique historical landscape of earthen dome villages in northern Syria that has continued to express the complex relationship between the environment, people and architecture over thousands of years. A second result is to examine the common roots between East and West demonstrated by the astonishing diffusion of corbelled architectural and building culture all over Europe and the Mediterranean. The Vernacular Architectural Heritage is important for our own future because such architectures are characterized by a high level of technical variability and integration in geographical and cultural environments together with their traditionally ecological and effective energy performances, which is of the utmost relevance, consistent “tacit” and local knowledge. Syrian earthen corbelled dome architecture expresses these characteristics at the highest level: the project presents to Syrian and international community an analysis of this architecture, to increase the perception and consciousness of the value of this local earthen architectural heritage in an effort directed towards the sustainable development of the Mediterranean. Giuseppe Lotti-Ilaria Bedeschi (a cura di – sous la direction de), Elles Peuvent. Progetti per gli artigiani della Valle del Drâa in Marocco Projets pour les artisans de la Vallée du Drâa au Maroc, pp. 96, 2007. Lino Centi-Giuseppe Lotti (a cura di), Design ± Infinito. Percorsi del progetto critico, pp. 96, 2009. Saverio Mecca-Letizia Dipasquale (a cura di – edit by), Earthen Domes et Habitats. Villages of Northern Syria. An architectural tradition shared by East and West, pp. 480, 2009. Next - Di prossima uscita Saverio Mecca, Letizia Dipasquale, Luisa Rovero, Ugo Tonietti & Vittoria Volpi (a cura di – edit by), Chefchaouen, Architettura e cultura costruttiva, 2009. Saverio Mecca, Silvia Briccoli Bati, Maria Cristina Forlani & Maria Luisa Germanà (a cura di – edit by), Earth/Lands. Earthen architectures in Southern Italy / Architetture in terra nell’Italia del Sud, 2010.

Earthen traditions are far too valuable to dismiss as irrelevant to the modern world and indeed future generations, they must remain as an example to the caring and ecologically aware architects and builders that are emerging around the world. (â&#x20AC;Ś) This European Union Project, and this book, have been achieved through a successful co-operation between the University of Florence, several European Universities and Institutions and the General Directorate of Antiquities and Museums in Syria, adds a valuable window, shedding light on the northern Syria tradition of striking domed houses. The ICOMOS Scientific Committee for Earthen Architectural Heritage applauds and encourages such excellent publications in the search for an accurate and useable worldwide typology and description of earthen buildings. This book contributes a great deal to these goals. John Hurd

President of ICOMOS International Scientific Committee for Earthen Architecture, Lincolnshire, Great Britain

Saverio Mecca, architect, full professor, is Dean of the Faculty of Architecture and Director of INNLINK-S Center on Innovation and Local and Indigenous Knowledge Systems of University of Florence Letizia Dipasquale, architect, is Phd student at Department Technology of Architecture and Design of University of Florence

This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein. European Commission

Education, Audiovisual and Culture Executive Agency (EACEA)

Culture Programme 2000