ADDA_02 by Anna Pla-Català

WEFT

• • • • A project in Research

Isabelle Weydert and Toon van Mieghem Master ADvanced design and digital architecture Elisava, Barcelona 2015-2016

Acknowledgements :

Director Jordi Truco Calvet

Lecturers Sylvia Felipe, Geometry and Natural Patterns Jérôme Noailly, Research in Bioengineering Ferran Vizoso, Animal Architecture Jordi Truco, Hypermembrane, Modular Complexity Javier Peña, Active Materials, Passive systems and Biomechanics of Materials Mireia Ferrate, Cybernetics Jalal El Ali, Buro Happold Experience

Teachers Sylvia Felipe

Fernando Gorka de Lecea

Eva Espuny

Marcel Burbina

Lorraine D. Glover

Pau de Sola Morales

Marilena Christodoulou

Roger Paez

Architect ETSAB, M;Arch AA Architect ETSAB, Emergent Technologies and Design AA BArch Pratt Institute School of Architecture Architect ETSAB, ADDA Elisava

Architect ETSAUN, ADDA Elisava Architect ETSAB, Master Digital Arts Pompeu Fabra Architect ETSAB, Phdw. Harvard Architect ETSAB, GSAPP Columbia

Anna Pla

M.Arch Comumbia University, M;Arch AA

Introduction

W.E.F.T. is an architectural system which is developed through the interest of finding guidelines in living systems and by the technique of form finding, in particular ‘ the weaving technique’ . We focused our interest in the way how W.E.F.T. could achieve a complex emergent structure just by a generation of a building through simple components. These phenomena of achieving a complex structure through simple elements can also be observed in biological systems. W.E.F.T. is a responsive system that is able to adapt to its environment in, particular to the wind and the view conditions. In the chapter ‘System, site, contextualization’ we can observe how W.E.F.T. is adapting to the environmental conditions of Vallcarca, Barcelona. The system W.E.F.T. is the result of knowledge found through material studies and the use of parametric software. W.E.F.T. as a woven system is part of the constantly developing society, where research is conducted to create state-of-art materials, such as composites, which are opening new possibilities of performance and which are created by new technologies and produced by the use of robots. The first part of this research project focusses on the results from the biodesign, including the development of integral envelopes as example of a self-organising system, a case study from architecture (shells by Félix Mandela), the results from our form-finding study using weaving and how the resulting W.E.F.T. system can comply to the criteria of a responsive system like biological structures in nature. In the second part – Abiotic architecture – growth capacities of systems in architecture are being studied, with parameterization of the W.E.F.T system taking winds and view into account, as well as contextualization of the W.E.F.T system for the location Valcarca near Barcelona. At last, some structural research for suitable materials was performed and possibilities are discussed, indicating the need for further research on composites as to build a W.E.F.T configuration at full scale (scale 1/1). At the end, pictures of the prototype (one on 1/50 and 1/250) can be found. . 7

Biodesign laboratory 14

Workshop integral envelopes

26 Nature as strategy for design, form structure and material (essay) 28 Abstract 29 Introduction 30 From lightness and nature to efficient architecture 30 Lightness 32 Emergence 33 Animal architecture 34 Techniques and technologies in morphogenetic design 34 Self-organization and material construction 35 Differentiation and performance 36 Polymorphism

37 Conclusion 38 Los Manantiales (case study) 40 Situation 41 Felix Candela 42 Reinforced concrete shells 42 Single curved shells 43 Double-curved shells 43 The hyperboloid of revolution The hyperbolic paraboloid. 44 Candela’s studies and his way of thinking 49 Los Manantiales ‘a life work’ 52 Conclusion 54 Form-finding process ‘ Weaving’ 55 Weaving, concept, types & industrialization 62 Weaving versus winding 64 Material research, setup and parameters 87 Conclusion

88 Responsive systems 90 Introduction 90 Examples and analysis 90 91 93 94 95

Wrapped, Omar Khan Faz Pavilion, Achim Menges, Steffan Reichart and Scheffler + Partner Topotransegrity - Non-linear responsive environments, Robert Neumayr Algae Canopy (Expo 2015), Claudio Pasquero and Marco Poletto How to analyse and criticize a responsive system?

W.E.F.T., a responsive system

Abiotic architecture 106 Growth capacities 108 Graph theory 114 Directionality 118 Compression rings 120 Continuous growth : roof and door 122 Parametrization 131 System, site, contextualization 132 Data collection and study of Vallcarca 135 Operative cartography 140 Spacial proposal 146 Placing the rooms depening on the view and wind . . . . 168 W E F T , a generative system? 184 Manufacturing diversity seminar 186 Cladding & structural research 186 Knots 187 Cladding 189 Conventional solutions 190 Breakthrough solutions

191 192

Prototype 1/250 Prototype 1/50

Bio-design laboratory

“Emergence is a concept that appears in the literature of many disciplines, and is strongly correlated to evolutionary biology, artificial intelligence, complexity theory, cybernetics and general system theory”. “In architecture the task, is to search for the principles and dynamics of organisation and interaction, for the mathematical laws that the natural system obey and that can be utilised by artificially constructed systems.” “It is the process that produces, elaborates and maintains the form or structure of biological and nonbiological things. The form of an organism affects its behaviour in the environment. It is non-linear and context-specific and will produce different results in different environments.“ Morphogenesis and mathematics of emergence, Michael Weinstock, p.10 AD May/June 2004 13

Workshop: Integral envelopes

During the integral envelopes workshop, directed by Sylvia Felipe, a picture of the microscopic view of the exoskeleton of the male louse (Pediculus humanus var. corporis) was studied. It was the first attempt to mimic nature by finding its geometrical principles and structural logics, whether or not related to its performative aspects. The objective was to define parametric variables and operative growth rules of this biological system. Based on the deduced parametric variables, rules for the allometric growth process were developed for our system. These growth rules enable proliferation of the system into a complex differentiated 3D envelope.

Pediculus humanus var. corporis, The microscopic view of the chitinous, exoskeletal surface of a male louse (leg joint)1. (Middle) Area analysis by centroids (image 1). (p.16, Right & p.17, Left): Reconstruction of the directions of the areas by using the centroids as elements of these lines (images 3-5). p..17: Geometrical principles of the linear proliferation: definition of the component (images 6,7). 1. Pediculus humanus var. corporis, Http://blog. sina.com/zhao [Accessed 10 Octobre 2015]. 16

After drawing and reconstruction of the grid in Rhino, the component was defined as an irregular octagonal shape.

Image 8: Quadrangular grid of the system and the perpendicular distances in the x-direction.

This shape is differentiated throughout the whole system by convex and concave angular transmutations in the x- and y-direction, as well as by the size of the inner quadrilateral shapes (see p.17). The length of each of the four sides of the quadrangle was studied in relation to the adjacent concave or convex angle. The height of the perpendicular to the side in relation to the concave or convex angle was alo measured. Both data were tabulated (see table, p.19). Based on these measurements, two parametric laws were derived for the proliferation in the x- and y- direction. The following images illustrate the reconstruction of the grid by applying these parametric rules (images 8-12).

Image 9: Quadrangular grid of the system and the perpendicular distances in the y-direction. Image 10: Reconstruction of the concave and convex shapes in the y-direction. Image 11: Reconstruction of the concave and convex shapes in the x-direction. Image 12: Reconstructed irregular octogonal shape grid by the defined parametric law.

Parametric Law Width y Height Width Height 11.075 0.19 concave 1.075 0.19 concave 1.201 0.226 concave 1.201 0.226 concave The relation between the mutations of 1.213 0.212 convex 1.382 0.23 concave each irregular octagonal shape and its 1.24 0.344 convex 1.433 0.175 concave inscribed quadrilateral was studied, by 1.311 0.291 convex 1.488 0.207 concave 1.382 0.23 concave measuring the length of the y-direction 1.433 0.175 concave Linear funtion of the quadrilateral side, in relation to 1.488 0.207 concave the convex or concave mutation length 1.213 0.212 convex a -0.4092 in the x-direction. 1.24 0.344 convex b 0.7839 1.311 0.291 convex x 1.609 Perp. Height Function: y=0.4092*x-0.7839 1.4 0.205 convex y 0.1254972 Width of the el. Width x Height 2.08 0.229 convex Linear funtion 1.444 0.129 convex 1.379 0.174 convex a 0.2120 1.666 0.214 convex b -0.2120 1.292 0.095 convex y 0.069 Perp. Height The same process was done in the 1.074 0 convex x 1.327 Width of the el. reverse direction, by measuring the The width and the lengths of the quadrangular shapes are measured between the corner points in relation to the heights of the corresponding perpendiculars.

width in the x-direction in relation to the perpendicular distance of the convex angle of the octogonal shape. Function y = 0,2120*x-0,2120

Based on these measurements and calculations, the next proliferation rules are deduced: The longer the inscribed quadrilateral shape in the y-direction, the shorter the adjacent angle in the x-direction. The wider the inscribed quadrilateral shape in the x-direction, the longer the adjacent angle in the y-direction. Subsequently, research was preformed as to create three-dimensional proliferation by new parametric rules. This process resulted into a new range of morphologies.

Images 13-15: Creation of different 3D envelopes by three-dimensional proliferation rules. Images 16-19: Production of the definite envelope by constructing the normal of each angle with the length equal to the distance to the centroid of the octagonal shape. Images 20-23: Possibilities of connections for proceeding by digital fabrication.

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Images 24-54: Possible geometrical patterns of the 3D envelope. Image 54: Final construction of geometrical pattern that is related to the directionality of each component.

After the creation of a three-dimensional structure, different patterns were designed on the basis of geometrical rules. A definite pattern is generated by following the directionality of each threedimensional component, as shown in the images.

Final envelope.

Manufacturing:

Digital production, which is the fabrication of the model by 3D-printing, was implemented into the system. Each component of the envelope was connected to the neighbouring components by their rotation points in common. Because the 3D-printer has limitations in size, the model had to be printed in 4 parts. In order to connect the 3D-printed pieces, a puzzle-like system was created in Rhino (see images 58 and 59). After creating the four pieces of the model, the polysurface had to be changed into a Mesh. Subsequently, it was exported to a STL-file for 3D printing (for prototype, see images on the right).

Final three-dimensional morphology which emphasizes the directionality of the envelope (images 56-57). Creation of a puzzle-like system for 3D printing (images 58-59).

Prototype.

Nature as strategy for design, Form, structures and material Essay

Abstract In this study, we analyze structural elements from living systems in nature relevant to architecture, and how to approach nature - from simple elements to complex emergent structures – in order to apply these systems into bottom-up architecture. The analysis shows that – in contrast to classic architecture applying existing knowledge and known solutions – nature has rather to be approached by open-minded research, going out from observation of the biological organisms, their emergence and morphogenesis, and analyzing these natural systems and theit components or elements. In these complex biological emergent systems, the properties are more than the sum of the parts, also demanding adaptation of materials as scaling progresses from small prototypes to real structures and buildings. Form, shape, geometry, properties of material and function should be taken into account, in order to design systems with less mass and energy, but with maintenance of optimum performance. Form-finding techniques and digital technologies have a key role in reaching these new forms of architecture, such as with our system W.E.F.T..

Introduction What is an optimal design, particularly when the form and shapes in architecture and design become predominantly changing, curved and organic as in nature? How to make designs that are using less mass and energy? Which shape or form is the best? Why is it important using less mass? The study of different books lets us learn about how nature and efficient architecture are related.1-5 And how designers through the process of form-finding and bottom-up thinking find the maximum performance of these structures with minimum energy consumption like for example resistance through geometry and not simply by addition of material. What we had to take in mind throughout our research and form-finding process is what D’Arcy Thompson mentioned in his book ‘On growth and form’:2 “If you want to build beyond a certain size, you should change properties or find a new (harder, stronger,…) material, otherwise it will be clumsy, inefficient.” Particularly as nature is characterized by lightness, emergence (growth) and morphogenesis, we analysed these aspects in this chapter with regard to their relevance and different approaches in architecture. This analysis has been consolidated based on information of the lecture of ‘Animal architecture’ by Ferrán Vizcoso (2015, Elisava) and the following books: ‘Lightness’ by Adriaan Beukers and Ed van Hinte (2005)1, ‘On growth and form’ by d’Arcy Thompson (2014)2,‘Emergence: The connected lives of ants, brains, cities and software’, by Steven Johnson (2002)3, and “Techniques and technologies in morphogenetic design” by Michael Hensel, Achim Menges and Michael Weinstock (March 2006)5 with reference to relevant pages throughout the text. The information has been further supplemented with other relevant references, wherever applicable.

From lightness and nature to efficient architecture a. Lightness Adriaan Beukers writes in his book ‘Lightness’ about how lightness is a necessity nowadays and in the future.1 In nature, shape is cheaper than material and so it is also more sustainable to produce lighter structures than heavy ones, because of spending less energy. Cheap energy is getting scarce.1, p.16 The structures should have less weight and should be maximally efficient to their necessities like in nature. In nature, animals adapt their shapes and structures to quickly changing loads. As mentioned in ‘On Growth and Form’ by D’Arcy Thompson,2 the form of an object is a diagram of forces, at least, from which we can judge or deduce the forces that are acting or have acted upon it. Such an interaction of a material with its changing environment is called smart or intelligent behaviour. 30

Smartness of a building is learning from the environment, adjusting the structure by responding to these changes, and remembering these adjustments. The ultimate smart structure would design itself by, for example, reinforcing and releasing material where needed, depending on the actual conditions.1, p.45-47

1. LIghtness, the inevitable renaissance of minimum energy structures, Adriaan Beukers, Ed Van Hinte, 010 Publishers, Rotterdam 2005 2. On growth and form, d’Arcy Wentworth Thompson, Cambridge University Press, 2002, p.11- 19

As Peter Pearce says ‘Structure in nature is a strategy for design’,1, p.49 even the most complex minimum energy structures are based in the end on the force systems and the geometry of the triangle. Polyhedra should be deconstructed into triangles to be made totally rigid and to be able to stand gravity, as only the tetrahedron, the octahedron and the icosahedron possess this property by theirselves.

Beehive made out of hexagons.1

In architecture, trusses and space frames are made by a conjunction of triangles. Hexagons can be observed as the construction component of a beehive: the shape occurs when the structures made of circles next to each other are pushed slightly together from all of the sides. The material shapes itself into the structure that best absorbs stress. Later we discuss in ‘Techniques and technologies in morphogenetic design’ the example of foam and his polyhedral structure (see image). Lightness is not only about light materials, but it is a balance between low energy cost, performance of the structure, utility and efficiency. The low energy cost is not only about the production of the structure, but also about the production of the material. Efficiency is all about how the material is working in the way it works the best. Some materials work better in compression, other materials in tension.1, p.23-35,138 Functions should be combined with material properties. The most interesting part of using composites is the potential to integrate different functions into one: this means that less parts are needed to construct. For example the sandwich composites in an airplane include both stiffness and sound insulation .

Composites also offer the advantage to produce any shape, like doublecurved surfaces. But composites have a relative brittleness; stress concentrations are caused by mistake in the places where different parts meet or where holes or cut-outs are made.1, p. 59-61 Stress concentrations by cut-outs can be solved by the structure itself, by not having to bear stress.

The known concept may not be the best solution at all. The roots of the original problem should be researched with and open mind to reach the best result with a minimum resources.1, p.161

Another advantage of using composites is lightness, which means less energy consumption. Total control of stiffness, strength and elastic deformation can be reached in lamination by manipulating the continuous fibre directions. The shape of built elements, such as in aluminium, can’t be changed in the same way as with composites, because traditional materials react to stress and tension in a totally different way. For example, metals undergo plastic deformation before they break, whereas reinforced plastics don’t, due to continuous fibres. Thus, using different materials, the shape of the built element should be rethought.1, p.59-79 Adriaan Beukers describes ‘the knowhow’ to build an airplane and the ongoing improvements of the used concept as a cause of loss of universality and overview.

Illustration of the theory that twodimensional compilations of more than three bubles are unstable. The resulting foam will always strive for minimum energy structures.1

b. Emergence Steven Johnson describes in his book “Emergence: The connected lives of ants, brains, cities and software”, different systems who are composed of simple elements which are organizing themselves spontaneously, without a specific law to form intelligent behaviour.3 This is the fact for ants, neurons, human individuals and others, as they base their behaviour on the changing environment without having a global view or the full knowledge of the whole system. Local rules take place and the global behaviour is the result of local interactions and changes. Emergence is rather a bottom-up than top-down system, created by master planners. A bottom-up intelligence is starting from the ground level, to build higher intelligence by recognizing patterns and storing information. 32

Agents like human, ants and cells, start to produce an organized behaviour that is on a scale above them; cells have no overall view, so don’t have ants and humans. The human body is made of trillions of cells working together. The human body is the sum of their actions; cells don’t have the global view of the whole body. Yet, cells follow the dictates from DNA and learn from the behaviour of their neighbours. Cells are communicating by salt, sugar and other chemical substances through the cell junctions.3, p.82 Similarly, the intelligence of ant colonies lies on the stupidity of the parts, and on how individual ants interact between themselves. The behaviour of the individual ant depends of his/ her immediate surrounding: he/she doesn’t have the knowledge of what is doing the whole colony; they don’t wait on orders from above.

3. Emergence, The connected lives of ants, brains, cities and software, Steven Johnson, Penguin Books, Great Britain, 2002

The complex system of the human body is made by connections of simple elements. Rterievd from www. shutterstock.com [Accessed 20 February 2016]

c. Animal architecture Something else, even more interesting than the emergent behaviour of ants, is the way how they construct or organize their ant hills. These ant hills were mentioned in the lecture of ‘Animal architecture’ by Ferrán Vizcoso, 2015, about architecture created by animals.4 Depending on the environment, climate and orientation, ants create a ventilation system to have the best temperature comfort in the nest.

The air is partly refreshed by letting it flow next to the outside, so it takes oxygen and loses a minimal of warmth.

4. Lecture 38: Animals, Insects, Lotus, Conclusion, Retrieved from: http://nptel.ac.in/ courses/107104076/lecture38/38_3.htm [Accessed 20 February 2016]

This is a genious solution to create the best comfort depending on the circumstances. Not only how the nest is shaped is important, but also how it is organized. The sequence of chambers and how the ants circulate, is brought to a minimum, in order to create the most efficient living environment. (See also section b. Emergence)

One option is to take fresh air in and let it flow through the nest to decrease the temperature. Another option is to recirculate the same air through the nest, to keep the warmth inside. The ventilation system of the ant hills.4

Techniques and technologies in morphogenetic design

The book ‘Techniques and technologies in morphogenetic design’ by Hensel, Menges and Weinstock,5 treats the theoretical and methodological foundation within a biological paradigm for architectural design, so studying the interrelationship between emergence and self-organisation concepts. Their previous book ‘Emergence: morphogenetic design strategies’ was about the concept of self-organization and the relation with architecture. Self-organization, we could define as a dynamic and adaptive process through which systems achieve and maintain structure without external control.5, p.6 It is important through the whole design process to see the behaviour of form, structure and material as one. These three different features act together and influence each other. This interaction is the most important point to keep in mind to come to a good form-finding design. This principle will be stressed further on and be explained with some examples. Self-organization and material construction Biological self-organization of systems (as illustrated in section b.) starts from small, simple components that are assembled together to form a larger structure that has emergent properties and behaviour. These elements in turn could be assembled into a more complex structure.5, p.35 In order to observe and analyse the development of biological self-organization, we can take foam as an example. The mathematical description of foam was for a long time a problem, but basically foam will organize itself in a randomized array of hexagon and pentagon structures.5, p.35 Thus a simple hexagon or pentagon can create a complex and interesting form only by organizing themselves in a ‘random’ array. So far, foams have mostly been used as insulation materials. Nowadays we start to investigate how we could use cellular foams as a structure. If we combine these foams with the industrial techniques and materials we know, we can create a strong and good performing structure. A metallic foam can combine its properties with the biological self-organization pattern to derive the forces and create an optimal structure (see also section a. Lightness).

Water cube resin model, based on foam arrays.5, p.35 5. AD ‘Techniques and Technologies in Morphogenetic Design’, Michael Hensel, Achim Menges, Michael Weinstock, AD Architectural Design, March 2006

Differentiation and performance Optimization of a structure is based on the understanding of efficiency that entails the minimum use of material and energy for the structure to fulfil its task. Optimization has given rise to lightweight structures with a minimum use of material to achieve the structural capacity and performance.5, p.61 “The proposed approach to architectural design is based on the deliberate differentiation of material systems and assemblies beyond the established catalogue of types, on making them dissimilar or distinct in degree and across ranges. Various ranges of material systems can provide diverse spatial arrangements together with climatic intensities. This involves the deployment of the inherent behavioural characteristics and modulation capacities of building elements and systems, rather than a retrospective optimisation process towards monofunctional efficiency.5, p.63 What we understand from this, is that we have to search and create an understanding of how a responsive structure can generate more solutions. A structure that can adapt to its environmental conditions and structural properties has more efficiency than every time creating one solution for one demand. To achieve this efficiency, analysing biological entities can help to create an efficient system. Mostly connections in architecture between parts are discontinuous and articulated instead of the smoothness we find in nature. The nature can help to find a smooth and continuous connection between elements.

Polymorphism Before discussing polymorphism, we have to define what we understand under this term. Polymorphism is the state of being made of different elements, forms, kinds or individuals. In biology, it refers to the occurrence of different forms, stages or types in individual organisms or within organisms of the same species. (See Introduction, p.29) Natural morphogenesis generates polymorphic systems that have a complex organization and shape from system-intrinsic material capacities and external environmental influences and forces. The result is a complex structure with hierarchical arrangements which we can derive back to a relatively simple component. The result in natural morphogenesis comes from a combination of material and form processes, these two are intertwined. In architecture, architects start mostly from the form and afterwards they see which material they can use to build the form, so they solve it as a top-down process. We have to see the capacity and complexity of a material as an ingredient to navigate the form and materialization process. The morphogenetic approach has to be a generative driver in the design process and not pre-established. This new approach will lead to a new way of thinking through the logics of production technologies and system performance.5, p.79

We have to combine the logics of formation and materialization, which enables to define specific material systems. All this encourages us to fundamentally rethink our current mechanical approaches to sustainability and a related functionalist understanding of efficiency.5, p.86

The book deals with five examples of morphogenetic design experiments ranging from homologous systems to polytypic species. The characteristics of integral form-generation processes, enabled through parametric association, differential actuation, dynamic relaxation, algorithmic definition and digital growth, are examined. We do not discuss the examples but recite some important thoughts they used to create their morphogenetic design. Differential surface actuations.5, p.81

Self-organization can be divided in two options. One option is a ‘global’ manipulation of the system. The other, a sometimes neglected option, is to act on a local component of the system. This local actuation will create a wave of deformations through all the components. The beauty of this option is that a simple form such as formed by rectangles can create a complex curved form just by deforming one rectangle. The simplicity of this one basic geometric form creates a global form that we never could have imagined. The whole system will also react within the limits and the performance of the specific material of the rectangles. This creates an intertwined solution as described above.5, p.82

Conclusion In the field of research for architecture, we should be open-minded for observation and research: researching the problem from the roots, and not from the already found solution. Also by observing living systems in the nature, we can create new structures and, by learning how nature is constructed and acting, we can discover new ways of designing. Living systems can be approached by imitating natural structural forms and understanding how biological organisms are made, emerge and are structurally organized, by analyzing them from simple elements to complex emergent structures. In these complex biological emergent systems, the properties are more than the sum of the parts. Research of the new possibilities of performance of state-of-art materials (like composites, as to strive for lightness), should be performed both from scale prototypes to real prototypes. By scaling, the material should be adapted. Form, shape, geometry, properties of material and function should be taken into account in the research process, as to design systems which use less mass and energy and who have an optimum performance. By designing systems based on such form-finding techniques and by using digital technologies, we can simulate new forms of architecture, such as our system W.E.F.T..

Los manantiales Architect: Felix Candela Location: Mexico Type: Restaurant Date: 1958

Situation The restaurant ‘Los Manantiales’ is located in Xochimilco in Mexico. The restaurant was built by Felix Candela in 1958 and it is one of his most famous buildings, based on his life research. Nowadays Candela and the restaurant ‘Los Manantiales’ still inspire other architects. He is one of masters who provided a big effort to establish novel approaches into the architecture and engineer world.

(Left): Félix Candela, Retieved from https:// en.wikipedia.org/wiki/F%C3%A9lix_Candela [Accessed 17 February 2016] (Right) Restaurant Manantiales, Retrieved from: http://www.archdaily.com/496202/ad-classics-los-manantiales-felix-candela/53493e7fc07a80f351000082-ad-classics-los-manantialesfelix-candela-image [Accessed 17 February 2016]

Felix Candela Candela was born in Madrid (1910) and graduated at the ‘Escuela Técnica Superior de Madrid’(1935)2, after which he travelled to Germany. Being a rationalist architect and teaching students, he was enchanted by the use of geometry in architecture. His life was marked by the Spanish Civil war: returning to Spain to fight against Franco, he was active in engineering the Spanish Republic, but was captured. He went into exile to Mexico and the United States, where he became famous as an architect for his thin-shell structures.1,3 1,2

From his youth, Felix Candela was attracted by the thin concrete shells structures of Franz Dischinger (Germany), a pioneer in the use of prestressed concrete. Candela started to apply this technique into his architecture. Today, he is considered one of the most prominent modern architects playing with thin concrete shells, known as ‘cascarones’ in Spanish. His fame was not only acquired by the construction of over more than 800 thin concrete shells characterised by rationality and optimal strength, but also by his ability for solving complex structural issues, and joining technical knowledge and philosophical reflections.1,3

1. Cassinello P, Schlaich M, Torroj JA. Felix Candela. in memoriam. From thin concrete structures to the 21st century lightweight structures, Informes de la Construcción 2010; Vol. 62 (519), p.5-26. http://informesdelaconstruccion.revistas.csic.es/index.php/informesdelaconstruccion/article/viewFile/1033/1119 [Accessed 17 February 2016, p.5] 2. Seguí M. “Esquema cronológico”. In: ‘Candela Pérez Piñero, un díalogo imaginal. Proyecto para el concurso del velódromo de Anoeta, 1972’, Seguí M. (ed.), Alcorcón, Madrid Rueda, 2004, p.46-49. 3. del Cueto Ruiz-Funes JI. “The shells of Felix Candéla”, Unam, Mexico, Retrieved from: www.revistascisan.unam.mx/Voices/ pdfs/5007.pdf [Accessed 17 February 2016]

He is one of the masters of the mid-20th century who claimed that a connection between shape and structure exists and that it goes beyond the pure outcome of calculations.

Reinforced concrete shells Shell structures have been constructed since the ancient times. The Pantheon in Rome is a well-known example. The ‘thin-shell adventure’ began in the second half of the 20th century. Architects influenced by Mies Van der Rohe’s assertion ‘less is more’ 4, wanted to conquer the new form and dimension freedom that concrete offered (at that time being a new material). The first thin concrete shell was designed by Franz Dischinger and Ulrich Finsterwalder in 1925, the Zeiss planetarium in Germany. In nature, we find leaves and grass blades folded around their centres of stiffness giving it a bending resistance. The stiffness, given by the folds cannot be reached if the leave would be flat. Any tendency to buckle is counteracted by the small width they have and by the fold. They are beam and form resistant surfaces, forming a ribstiffened membrane. Some man-made things made with this principle include corrugated paper and corrugated metal decking. The tension is taken mainly along the upper parts of the sides and the compression in the valley. Shells in buildings can take many shapes and curvatures. Their main properties, based on the beforementioned principles from nature, are lightness, thinness and strength.5,6 However, shell structures also have the limitations, as they are weakened by 42

openings in their surface; they can crack or crush due to material nonlinearity and tend to dislike point loads which inevitably introduce the possibility of local buckling (large deformations).5,6 The shells can be single or doublecurved surfaces. The curvatures can be found by mathematical calculations or by form-finding.6 Single curved shells Single-curved shells are curved on one linear and are part of a cylinder or cone in the form of conoid shells or barrel vaults. The stresses are still in the surface plane that is able to resist deflection, so the inherent stiffness is arranged in that plane, thus along its surface. They are easy to construct, but have the disadvantage of being developable: they can fail by flattening or unrolling into the flat sheets they were made from, even without having to tear or buckle. Therefore, curved edges may have to be thickened or lateral diaphragms may be used across the shell to resist the unfolding tendency.

4. Cassinello P, Schlaich M, Torroj JA. Felix Candela. in memoriam. From thin concrete structures to the 21st century lightweight structures”, Informes de la Construcción 2010;Vol. 62 (519), p.5-26. http://informesdelaconstruccion. revistas.csic.es/index.php/informesdelaconstruccion/article/viewFile/1033/1119 [Accessed17 February 2016, p.6] 5. Peerdeman B. Analysis of thin concrete shells revisited: opportunities due to innovations in materials and analysis methods, Master Thesis - Total Report, TU Delft, 2008. Retrieved from: http://homepage.tudelft.nl/p3r3s/ MSc_projects/reportPeerdeman.pdf [Accessed 17 February 2016, p.5]

Single-curved shells: barrel vault and conoid.7

Double-curved shells

The hyperbolic paraboloid.

Double-curved shells use geometries with curves running in the same direction (synclastic) or running in opposite directions (anticlastic); they are part of a sphere or a hyperboloid of revolution7, such as in domes. Double-curved shells have the enormous structural advantage of being non-developable (inherently rigid).

As shown in the image on the right, the hyperbolic paraboloid has an opposed double curvature, being convex one way along the surface and concave the other way (saddleback shape). This structure can be defined by two sets of intersecting straight lines, so there are two directions in which the surface is straight.6 It is impossible to model a saddleback shape from an uncut single sheet of paper. The stress flow in a hyperbolic paraboloid roof is compressive along the convex parabolas downwards and tensile at the right angles along the concave parabolas.6 If you look to the hyperbolic paraboloid roof in profile, you can view the resulting stress tendency for tension along the top and compression towards the bottom. The convex parabola pushes, while the concave parabola pulls.

The hyperboloid of revolution This shape is created by the revolution of a plane curve. This curvature at model scale can be obtained by connecting two circular hoops with straight threads and then turning on and off the hoops relative to the other.

6. Reid E. Surface structures. In: ‘Understanding buildings a multidisciplinary approach.’ The MIT Press, Cambridge, Massachusetts,1984, p.31-32 7. Shell structures advanced building constructions, Retrieved from: http://www. slideshare.net/shwetamodi23/shell-structures-advanced-building-construction [Accessed 24 January 2016]

Construction of hyperbolic paraboloids.7

Concave parabola

Convex parabola

= Double-curved shells: hyperboloid paraboloid and dome.7

Hyperbolic paraboloid.

Candela’s studies and his way of thinking In all the work of Felix Candela we find an example of the search to react against external forces. The prime issue according to Candela is the awareness of the structural shape in relation to the material. It are two aspects of the same problem.8 On one side, structural problems can be resolved by allied formalism and forms. A roof is a problem because of its weight; this is also why - in Candela’s view - the area of the roof is of great use for searching resisting shapes.8, p.134 A simple example is found in a sheet of paper which by itself is incapable to withstand its own weight. Only by changing the shape, which is changing the placement of the material (folding the sheet of paper), the shape gains considerable resistance. To understand the resistant shape of an arch, we only have to look to a chain suspended between two points. By its own weight, the chain adopts its shape into the only form it can resist. This principle is called working in traction (it will only work if it can be stretched). Any force acting on it will deform the shape.8, p.165-167 The famous diagram by Poleni from 1748 shows that the shape of a chain should only be inverted to form an arch. The forces acting on such arch are opposed to traction and are transmitted by the lines, so it will only compress. But as earlier mentioned, if the chain needs to support other external forces, the shape will change into another shape, and when this is inverted, it will show an ideal arch for those weights.8

Poleni’s drawing of Hooke’s analogy between and a hanging chain and an arch.8 8. Discovering Hypars, Candela Pérez Piñero, Miguel Seguí, Editorial Rueda 2004, p.138 - p.165-167 9. Los hypars de Félix Candela, Retrieved from: http://www.jotdown. es/2011/11/los-hypars-de-felix-candela-i/ [Accessed 19 February 2016]

Experimental antifunicular vault, first model at real scale (+/-6m).9 44

This simple observation lets us understand the mental formality of Candela. By inverting a power cable, he designed his first shell in 1949. The shell was made by hanging different modes of hessian sacking between small wooden arches. When pouring the concrete, the sacking was deformed by the concrete into a shape, similarly as the power cable, and a double-curvature structure was created. The weight of this vault only works against compression; warping and bulging problems were resolved. But there are other problematic forces acting on a building than its own weight. Let us thinking at snow, wind, thermal dilations,… By pulling a cable, the cable gets more stretched (traction), which is a stabilising force. In contrast, compression is a destabilising force which can weaken, damage the structure. This can be compared with a person walking with a stick. The stick will double, because the weight caused by compression destabilises the form, whereas the force is traveling through (in this case) the stick. This is why inverting a cable to withstand compression is not enough to design a shell. To make a vault more rigid and resistant, without thickening the material, the shell can be undulated in the direction of the vault. This is similar to the principle of the sheet of paper, as earlier mentioned. Candela experimented different kinds of vaults like shown in the image below:

Examples of simple shell structures based on formwork with a sack cloth, as performed by Candela. Top-down: Parabolic arch, vault shaped by the union of right line and a hyperbolic arch, shell with elliptic guideline, parabolic hyperbolic vault of a lower arch, Formal sheet with catenary guidelines.7 45

These undulated forms can be observed in one of his first “Will Shell” (1951), which was built with his company ‘Cubiertas Ala’. The shell is a conoid, with a span of 14 m and a thickness of 1.5 cm. It was seen as a base element in industrial architecture. The slogan of the company was not for nothing ‘specialists in industrial architecture’. Yet, the shape of the Will Shell didn’t convince him of its structural universality. Soon experiments were made with long cylindrical vaults with lenghts about 12 m, without edge beams. Calculating them as hollow, cylindrical section beams were constructed and also covered saw tooth using long cylindrical vaults. The interest of Candela was to understand the resistant forces by trying to reduce the thickness of an element, eliminating edging beams and challenging forces in new ways. On the other side, there is the problem of the material. Material gives shape and determines the way of working. It has no utility to select a shape in which the material cannot withstand the tensions. Scaling micro-shapes up will reduce the possible solutions. This is one of the reasons why Candela questioned the issue that the material used in models always is different than in reality,8 The hypar was the solution, which could be created by a simple construction method and which was easy to calculate. The hypar gives a lot of spatial possibilities and formal solutions, like for example in ‘Los Manantiales’.8

One of Candelas’ first Will Shelfs at UNAM, Mexico.8

In reflexion, Candela proposed that models should be more precise in design, such as possible through computer modelling of structural behaviour. Compared to manual design, computer models are quicker in calculations and allow better understanding of the structural behaviour, as they allow the designer to visualize flexes, deformations and stresses within structures.12

10. Picture of UNAM, Retrieved from: http://www.odonto.unam.mx/admin.php?IDPagina=acercade&id=311 [Accessed 19 February 2016] 11. Retrieved from: https://es.pinterest. com/pin/143270831867735881/ [Accessed 19 February 2016] 12. Digital architecture and construction, A. Ali, C. A. Brebbia, WIT Press, UK, 2006 Félix Candela, Construction of Iglesia Narvarte, Mexico.11 46

There is a need of certain degree of idealization in mathematical models, by interpretation of the material in the work with all the imperfections in relation to construction process. Candela says in his report of 1951 “Towards a new philosophy of structures’ that calculations cannot give form to structure, but it can split only the form up. ‘Maths doesn’t produce the perfect shape’. He was conscious of the limits of calculation. The structure’s behaviour should first be analyzed and later be compared by mathematical calculations. These structures should be made in reality, or we should look at real examples.8 The theory about the relationship of proportion and size was already described by Galileo Galilei in 1638. The famous issue in his book about bones of different sizes - in which one bone has three times the length of the other, illustrates the disproportion of size. 8,13 The bone doesn’t maintain the same proportions in volume, to be equivalently effective for support. If you scale the linear dimensions (length, width, height), a dog of 30 pounds magnified three times would weigh 27 times more (800 pounds). If the bones are scaled up 3 times, the strength of the bones will only increase 9 times. These can’t support the 27-fold increased weight. This is why the bones of a horse are proportionally much thicker than the ones of a dog to support the weight. This is also why short-span bridges can take many other shapes than large ones.13 Dealing with thrust, so the vault or dome would become a self-carrying structure, was only possible since the appearance of steel as construction material. This material permits that vertical strains are transferred to the supports that are holding the dome or the vault up and the material also reduces the weight of the structure, by the lightweight of the material and reduction of the thrust. 8, p.139-141 The grid of the vault should be determined in a way to balance the tensions as observed in the internal structure of a bone. The mass is specialized in moving out in directions of the forces, which could be seen as a cramped mesh. The surface is like a lattice. By emptying out the mass, strains could be deformed. It is essential to follow the principle of triangulation which gives the structure geometric rigidity and gives the possibility to create lightness as mentioned in the essay of the book ‘Lightness’ by Adriaan Beukers.(p.30 1, p.56) Triangulation has a wide range of possibilities, in particular, for the elements that must bend like the Fort Railway Bridge in Scotland and the wordwide used truss system. Another example are the electrical pylons in Russia from 1927-28 by Vladimir Suchov, mentioned in the chapter ‘Responsive systems’, using the principle of triangulation in a refine-shape mesh8.

Scaling of bones: the bone below shows the scaling up of the upper small bone to the same length as the larger one: this bone is much thinner than the one of a big animal, which would be to heavy for this thin bone.13 13. Scaling the strength of bones. In ‘Galileo Galilei: First Physicist’, James MacLachlan, Oxford University Press, USA, 1999, p.98-99 14. Retrieved from: http://www.imgmob.net/forth-rail-bridge-photo.html [Accessed 19 February 2016]

Fort Railway bridge of Scotland made by a truss system based on the triangulation principle.14

Felix Candela combined the principle of triangulation with his knowledge of hyperbolic paraboloids in his proposal design for the Crystal Palace in London. The design was a tree-like structure of combined triangulation (see image). Candela moved in this stage from his shell study to a lattice system in which he brought together his linear elements and his beloved double-curvature surfaces. The movement out of the shell structure gave him the possibility to design buildings with a larger span, as he realized in 1968 when he designed the Sport Hall for the Mexico Olympics.8, p.148-158 and 169;16 Felix Candela designed a dome which was a symbiosis between lattice elements and double-curvature surfaces, made by two kind of transversal arches. These transversal arches are formed by the intersection of cutting planes where the pole of the dome is located. The hypars were triangulated and interwoven in the weave of the arches, in order to act as roofing and triangulation. The division is made by rhomboidal panels, all with a different kind of joint, which made it a complex structure. But natural light came in in a spectacular manner. The division of a spherical geometry has been an eternal challenge and has been faced by R. Buckminster Fuller with his Geodesic Dome, Dischinger Dickerhoff Widman with his design of the Planetarium in Jena (1920) which is a giant steel radiolarial dome, and by many others investigators of lattice structures.8,16

Shukhov Tower: made with a triangulated refined mesh.15

15. Shukhov Tower, Retrieved from: https://en.wikipedia.org/wiki/Shukhov_Tower [Accessed 18 April 2016] 16. El triángulo rígido, image Crystal Palace. In: ‘La estructura veloz: Trayetorias estructurales à proposito de la obra de Emilio Pérez Piñero y Félix Candela’, JoseMaría de Churtichaga. http://www.chqs.net/archivos/informes/ archivo_1_040310_la+estructura+veloz.pdf [Accessed 11 March 2016, p.15] 17. Félix Candela’s shells at the Art Museum of the Americas, Retrieved from: http://urbnexplorer.com/2015/02/25/felix-candelas-shells-at-the-art-museum-of-the-americas/ [Accessed 11 March 2016]

Palacio de los Deportes (Palace of Sports), Mexico 1968, a symbiosis between lattice elements and a double-curvature surface.17 (Left) Crystal Palace sketches by Candela, consisting of a tree-like structure of combined triangulation.16 48

Los Manantiales ‘ a life work’ Perhaps the most famous of the vaults of edge with hypar saddles is the octogonal shape shell of the restaurant Los Manantiales in Xochimilco. It was made to replace a restaurant destructed by fire.18

The roof is a circular array of four curved-edge hypar saddles that intersect at the center point, resulting in an eight-sided groined vault. The plan of the shell is radially symmetric with a maximum diameter of 42.7 m. The height of the highest point reaches 9.93 m, while in the centre of the building it reaches 5.84m. 18,19

18. Analisis grafíco de obras emblemáticas de Felix Candela’, Andrés Martín FR, Fadón Salazar F, XVI Congreso Internacional de Ingenieria Grafica, 2004. Retrieved from: http:// www.egrafica.unizar.es/ingegraf/pdf/comunicacion17102.pdf [Accessed 19 February 2016] 19 . Análisis estructural de algunas cubiertas de Félix Candela, Oliva J, Antolín P, Cámara A, Goicolea ZM, HORMIGÓN Y ACERO 2011, 260, 61-76.

Los Manantiales: Overview of the ochtogonal shell shape from the upper side.20

Los Manantiales: Section roof plan and bar arrangement.20

The largest forces of the membrane are carried along the intersections between the forms (the groins). These parts are thickened by creating hidden steel reinforced “V” beams. The groins are spanning 32.4 meter support.9 Candela softened the form at the intersection of the hypars, creating a curve and giving the structure the appearance of a continuous form. Trimmed at the perimeter to form a canted parabolic overhang, the shell simultaneously rises up and out at each undulation. The force paths from these overhangs act in the opposite direction from forces along the arched groin, reducing outward thrust.19

Los Manantiales: Intersection planes.20

The rest of the structure has minimal reinforcing to address creep and temperature effects, but essentially works entirely in compression. The symmetrical plan and innovative use of “V” beams allows edges free of stiffening beams, revealing the radical thickness of the 9 cm shell.19 The section shows the parabolic arch along the groins and the inverted arch through the highpoint of each vault. For the footings Candela used inverted umbrella forms who are linked by 5 steel tie-bars of (2.5 cm diameter) with the groins of the shelf.

Los Manantiales: Section and north elevation.20

The advantage of these footings is that they contain the ground in a way that they don’t sink into the ground. Another way to withstand the lateral forces was effectuated by connecting the footings.

20. AD Classics: Los Manantiales / Felix Candela, by Michelle Miller, 14 April, 2014, Retrieved from: http://www.archdaily. com/496202/ad-classics-los-manantiales-felix-candela [Accessed 19 February 2016]

Construction: The formwork was realized by following the generated form of the paraboloids. It was one big mould for whole the construction (8 repetitive elements), because the structure was designed to function as an ensemble and not as separated. Once the construction of the formwork was completed, reinforcements were placed and proceeded to concrete.

Construction of ‘Los Manantiales’.20

In conclusion, the shell design by Candela was revolutionary, using concrete, a new free-form material exploiting its lightness, thinness and strengths, while simultaneously offering form and dimension freedom and combining these. In his master work ‘Los Manantiales’, he used 4 curve-edged hypersaddles (hyperbolic paraboloids) intersecting at the central point to compose an octagonal shell shape as roof for a restaurant, exploiting the material and shape to lead the forces. Candela reached the summit of his expertise in the late nineteen sixties. At this stage, his place was taken by new types of lightweight steel and, eventually, other new materials. The decline became clear in 1969 following the decision of the IASS, the International Association for Shell Structures, to change its name. The place of shells had vanished and was taken by eventually other new materials. Although concrete shells continued to be built very sporadically until they finally all but disappeared in the late nineteen seventies, Candela inspires modern architecture not only by his curved shapes based on nature but also by his way of thinking and his process of form finding. According to Candela, the structure should be first analysed physically, and then mathematical formulas should be deduced and be used to calculate the forces and to digitalize the structure.

FORM-finding process Weaving introduction Industrialization examples Research 55

Weaving, concept, types & industrialization Weaving as form-finding technique is, in our research process, a way to experiment and learn from the material. Subsequently, based on the derived knowledge of the material and its intelligent behaviour, a form will be created. The technique of weaving in conjunction with the material will enable us to produce designs that are innovative in form, behaviour and material. The following analysis of weaving is a study to better understand the process, properties and opportunities of weaving and to find ways of digitalisation and robotic fabrication.

After finding a circular woven nylon-like material (see images on the right) with special structural capabilities in compression and tension, research on circular weaving was started. The aim was to find out whether we can produce this woven material by using other materials and which parameters influence its capacities. In compression the material gains strength, in tension it flattens and in rest it is a circular flexible material. Weaving is the interlacing of two or more yarns, using a loom. Yarns can be wool, silk, cotton, flax yarn, hemp, wool, jute or other vegetable fibres.

Weft (longitudinal threads) Warp (lateral threads)

Weft and Wrap

Woven synthetic fabrics have the characteristic to be strong. Weaving is one of the techniques like braiding or knitting who can be applied to composite materials.1

(Right) Circular woven nylon-like material in rest, compression and tension. 56

Three main types of weaving exist: • Plain weave Each warp (longitudinal) fibre passes alternately under and over each weft (transverse) fibre.2 • Satin weave 3/ 4 or 5 or more weft yarns floating over a warp yarn or vice versa • Twill weave The weft thread passes over one or more warp threads and then under two or more threads and so on, with a “step” or offset between rows to create the characteristic diagonal pattern.2

1. Frozen fabrics, In ‘Lightness’, Adriaan Beukers, Ed van Hinte, 010 Publisher, Rotterdam, 2005, p.129-139 2. Woven fabrics, David Cripps, Gurit Retrieved from: http://www.netcomposites.com/ guide-tools/guide/reinforcements/woven-fabrics/ [Accessed 12 January 2016]

Satin weave: Each warp floats over three wefts and passes under one.2

Structure of a 2 to 2 twill. The offset at each row forms the diagonal pattern.3 3. Twill, Retrieved from: https://en.wikipedia.org/wiki/Twill [Accessed 12 January 2016]

(Left) Plain weave - twill weave - satin weave pattern4 applied in circular woven prototypes.

In the first part of our form-finding process, we tried the plain, satin and twill weave. As shown in the images above. based on these tests, we could conclude that the strongest weave is the plain weave, because each wrap passes alternatively over and under each weft. We decided to go onwards with the strongest option.

4 Bethune & fils: linnenhandel Kortrijk, 1735-1856, Retrieved from: http://www.ethesis.net/bethune/bethune_deel_I_hfst_2.htm [Accessed 20 April 2016]

Before going on with the project we studied the industrialization process of weaving and some other projects where weaving was used as a form-finding process. 57

Industrialisation process: Before there is the possibility to weave the threads, depending on the material, the material will firstly be spun or extruded parallel. When the material has the right shape to be processed in a woven structure, this materials is sometimes first bleached or painted. The principal motions during weaving include shedding, picking and battening (or beating in): Step A: Shedding Warp (longitudinal) threads are kept under tension to facilitate the interweaving of the weft (transverse) threads.

Shedding.4 4. Fabric weaving, Retrieved from: http://www.textileschool.com/articles/149/fabric-weaving [Accessed 8 December 2015]

For each row has to be woven, the warp yarns are raised or lowered, to make room for the shuttle to pass through with the weft yarn. The shuttle is a projectile that holds weft yarn and take the yarn underneath and over the warp yarns. Step B: Picking The weft (filler) yarns are laid across and between the warp yarns as the shuttle moves across the shed. The weft (filler) yarns are being woven as the shuttle moves across and between the warp yarns. Each length of yarn, fed from the shuttle as it moves across the loom, is called a pick.

Picking.4

Step C: Beating in The reed is pushed against the last filler yarn and against the woven cloth. The position of the warp yarn is again changed and the weft is brought back directly in the return direction. These steps are continually repeated until the woven synthetic fabric is produced. By this way of producing, a selvedge is created, . Beating in.4

A selvedge is forming a strong edge by the weft yarn turning and returning at the edge. It is the strongest part of woven synthetic fabrics; it will not fray and unravel like a cut edge.

5. Woven fabrics are produced by the process of weaving, Retrieved from: http:// china-polyestermesh.com/news/news_57.html [Accessed 8 December 2015]

Rapiers systems:

A rapier loom is a power loom, whereby a stationary package of yarn is used to supply the weft yarns in the rapier machine. (In a traditional loom, the filling yarn is wound onto a quill, which in turn is mounted in the shuttle.) Very different yarns can be woven.5,6

The rapier head grips the weft yarn crossing across the width of the grid, carrying the weft yarn through the shed to the opposite side, to be subsequently retracted, leaving the new pick in place.6

There are 4 types of rapier systems:5,6

Single rapier:

6. Images from movie’ ‘Type of Weft insertions in weaving loom’, Retrieved from: https://www.youtube.com/watch?v= s0W0iDj7_hc [Accessed 8 December 2015]

Double rigid rapier:

This rapier works faster, as one rapier carries the yarn to the centre of the shed, where the opposing rapier picks up the yarn to carry it across the remainder of the shed, so there is only half the distance to travel.5,6

Double flexible rapier:

A flexible rapier can be coiled as it is withdrawn, requiring less floor space for the machine; these machines work even faster than the double rigid rapier because they are lighter and may work with flexible rapier bands that are wound on wheels or placed in semi-circular channels so that, when they are withdrawn outside the shed, the result is a wide fabric up to 5 m.5,6 59

Double telescoping rapier:

This industrial loom has all the advantages of a flexible loom, but makes use of an automated sliding or a telescopic devising, as to insert the filling yarn. The loom is running steadily at the high speed due to the automatic pick finding system, without much vibration. There is an extreme wide adaptability to variety.5,6

Several filling processes can be used: a)

Projectile filling system:

This system uses a gripper to carry the filling yarns across the shed. The projectile just grips the yarn before it is propelled through the warp shed, where it is caught at the end and send back. The projectile doesn’t have to carry the weft package, so it goes much faster.6

Airjet filling system:

This approach uses a stream of high presses air to insert the loom into the work shed. This system reaches the highest production speed. It inserts the filling from an outside loom auxiliary yarn system that accumulates the exact amount of wire needed to travel across the shed. An initial push of air starts the yarn on his way.6

Fibrous Organizations (2003-2004) This project aimed to understand and instrumentalise the self-organisational tendencies of woven materials, by manipulation of single threads within a woven fabric. The effect was studied on the local and overall area. Threads were pulled and misplaced to get a controlled contraction of the fabric into a series of emergent folds. Each resulting deformation was hardened with resin, measured, mapped and digitised. The first tests were taken on a homogeneous woven fabric, then on heterogeneous woven fabrics with multiple densities and irregular intervals between the fibres. The scaling process of the behaviour of the material involves the careful consideration as to whether the entire woven structure has to be scaled, or its behaviour has to be retained and just the system be translated. The system was translated into a malleable lattice layout by articulating the rods differently, by changing joint types (enable or constrain movement locally or by region), by non-uniform lattice layouts (stiffen or weaken regions) and by layering.

- Cordula Stach The utility of layering of lattices takes place when, between more malleable regions, a certain curvature needs to be retained.

Material systems, fibrous organisations, Cordula Stach, In: ‘Morpho-ecologies Towards heterogeneous space in architecture design’, Michael Hensel, Achim Menges, Architectural Association and authors , London, UK; 2006, pp.100-111.

The lattice was tested with sliding flexible and fixed joints, because the degree of malleability had to be varied in the whole system to cope with compressive and tensile forces. This complex behaviour is similar to that in the fabric piece but eliminates some important properties of the woven fabric. Likewise, the intrinsic multiscalar differentiation of the fabric, the lowtech fabrication technique and the redundancy principle. These challenges could be solved by using or developing materials with comparable properties like steel wire, glass or carbon fibre (similar fibre structure) or composites with a fibrous material. Cordula Stach created with the knowledge of this system, an office landscape using a matrix of interconnected rooms by draping the lattice over defined spaces. Circulation and visual connectivity were used as parameters.

Weaving versus winding To better understand the difference between weaving and winding, a winding pattern was created, which can easily be created by one robot. The interlacing of the strings by the process of weaving over a circular plastic tube creates a cylindrical shape . On the other hand, the process of winding over a circular tube will expand to a conic form after removing the tube. This is due to the number of times that a string goes over and under another one. Further during the process, resin was applied to a winding and a weaving pattern, both using a s-curvilinear shape. The weaving pattern kept the shape as well as the threads interlaced. In contrast, the winding approach returned to an almost completely flat surface, and the threads became loose. The images on the left illustrates the weaving versus the winding pattern. using the same obliquity of strings (also called further on ‘shift’) and the same material (acrylic wool). It is clear that the weaving pattern stays more in shape than the winding pattern.

140

Weaving (plain weave) versus winding pattern, using the pattern below (acrylic wool).

Winding and weaving pattern (unrolled circle). The obliquity of the strings goes from number 1 to 14,: these are representing the holes through which the string is passing. 62

Trying to mimic the weaving pattern by the winding technique, a pattern was created that easily can be produced by one robot, by changing always the directionality of the next string in a specific sequence. As we can observe, the crossings of the strings are not always joined due to the winding technique. This phenomenon proved that the winding technique is weaker than the weaving technique. This was the reason why for further research the weaving technique was selected. This also means less material and more lightness, two important concepts already mentioned in the essay of ‘Nature as strategy for design, form, structures and material’. The observations therefore also suggest that weaving a building may be a cheaper solution.

140

Weaving pattern (plain weave) versus winding pattern (acrylic wool + epoxy).

The image on the left shows the pattern followed to make the winding and weaving prototype, using a s-curvilinear frame. It shows the obliquity of strings in both directions (going from 1 to 7).

Distribution pattern of the strands going from 1 to 7. 63

Material research and setup To study the characteristics of circular weaving, some parameters had to be defined. That’s why we started with a standardized setup, always changing one parameter only. It is important to generate rigorous results, to deduce values for parameterization and achieve valid conclusions.

140

5 mm plywood, 28 holes

Plastic tube, 140 mm height (total height 150 mm and 60 mm radius)

The parameters were studied, varying both the material and dimensions in relation to their flexibility, strength and density. Furthermore we studied the directionality and the connections.

5 mm plywood, 28 holes

Basic setup to reproduce a circular weaving pattern using a plastic tube.

5 mm plywood, frame Metal bars In-between distance 140 mm height

5 mm plywood, frame

Basic setup to reproduce a circular weaving pattern using metal bars.

Basic setup to reproduce a circular weaving pattern The setup was made by combining a plastic tube of 150 mm high and a radius of 60 mm, with two circular wooden elements of 5 mm thick at the ends. The height between the wooden circles is about 140 mm. Each wooden ring has 28 holes. As weaving thread, acrylic wool yarn, was chosen in two colours, blue and purple, to facilitate the weaving process by hand and in order to avoid human errors. After the first circular weaving tests, we concluded that the inner tube had a lot of influence on the obtained shape, so we changed it to supporting metal bars, as to maintain the height for the next shapes.

Acrylic Acrylic

Polyethylene Polyethylene

Latex Latex

Rubber Rubber

Velpon + water

Foam Hair Anti-Frizz

In the next stage, we studied the flexibility, strength and density by changing each time a specific parameter during the circular weaving process, such as height, radii, shift and quantity of strings. We also digitalised these shape changes into a digital model. Stiffer, still soft Stiffer, still soft Smooth compr. Smooth compr. & snaps & little snaps Flexible torsion Flexible torsion Other charcs backside Other charcs backside

Stiff Stiff No Strongest flexible compr. NoFlexible flexible torsion compr. snapsbackside OtherBig charcs Little torsion Other charcs backside Glued to tube Other charcs backside

KeepsSmoothness Smoothness Keeps NoSnaps Snaps No FirmerFirmer & stronger Flexibletorsion torsion Flexible compression &&compression All holes filled All holes filled Othercharcs charcsbackside backside Other

Acrylic paint

Ployethilene

Bostik glue for stiff and flexible plastics

Fixation Gel

Firmer Flexible compression Flexible Torsion Other charcs backside

Firmer But yet soft Spans Smoothness Other charcs backside

Test failed failed Test Noadded added second second No component!! component!!

Test failed Failed No addeddoesn’t second Velpon component!! resolve in water better use woodglue. 50% - 50%

Latex

Liquid plastic

Velpon

Hair fixator

Hairspray Extra strong

Sugar & hot water

Cristal Sugar & hot water

Paraffin & stearin

Dry process: Under tension Long time Need Clingfilm

Losing Smoothness Snaps stifness warming loosing caracteristics

Sugar fine grain

Sugar

Stearin

Little Little stiffened stiffened No No strongness strongness Smooth Smooth No Nospans snap No signification (less fraying)

We also studied different composites of acrylic wool (see below). We started the form-finding process with acrylic wool and liquid plastic. Subsequently, we changed the composite, because acrylic wool frayed out a lot, producing sloppy, inaccurate results. The composite was changed to cotton and epoxy, being more accurate, clean and ecological, while it achieved practically the same structural properties as the initially tested wool composite.

Bostic glue

Giorgi gel

Firmer But yet soft Spans Loose smoothness

Fixative

Parameters

Latex

Resin: Liquid plastic

Comparing latex and liquid plastic

Application process

Dipping

Superficial with brush

Dryprocess

Longer: 20 hours Turning the element / time Result: expanding

Shorter : 30 - 45 min Result: rather schrinking

In the table on the left, the results obtained with the best composites of the wool are being compared.

Radius

Smaller Radius

Bigger

Length

Longer, more deformation

+/- always the same height

Distribution

Partly filled holes (3/4th shift acts like one string)

No filled holes

Torsion

System more flexible: can turn more

Less flexible: depending of density and shifts and thickness of material apllication

Tension

Less

Strongness

Less weight lifting Elastic

More weight lifting Brittle: to much weight creates a permanent deformation

Shift

Quarter turn Max. x gr

Half turn Max. x gr

Three-quarter turn Max. x gr

Latex

Liquid Plastic

As shown in the images below, the liquid plastic is stronger and the latex is more flexible.

In order to study the influence of the shift, three kinds of patterns were made. These are shown in the images on the left.

Shift 1 to 7, quarter turn

Circular weaving with a quarter turn around the plastic tube was achieved in the least time, had the least density and used the least material. The higher the shift, the denser is the resulting weaving pattern, due to the quantity of strings going over and under each string. Differences became visible when removing the inner plastic tube: different sizes of cores appeared. The core is smaller, the higher the shift, and the woven fabric is getting longer.

Shift 1 to 14, half turn

The left image below shows a quarterturn pattern on a tube and the right one shows this prototype without the tube.

Shift 1 to 21, three-quarter turn

After analysing different densities and shifts, a circular pattern was cut and folded open. A s-curvilinear shape appeared and some push-reaction movements due to the woven pattern were detected. To study this open shape more accurately, a s-curvilinear frame with 56 holes was designed. The first open prototype was made using a plain weave as usual, with a quarter shift (280 mm) and a distance of 140 mm between the frames. These dimensions are the same as those used in our circular weaving studies. Using acrylic wool and liquid plastic, some composite problems such as irregular absorption and lack of stiffness were detected in this first prototype as illustrated on the left. A new stiffer and more accurate composite was achieved by using epoxy resin and cotton wire. R65 R65

Setup of the s-curvilinear shape.

Technical plans of possible s-proliferations of woven structures with s-curvilinear shapes. with radii of 65 mm each. These plans were used to lasercut the frames for the single, double and triple s-curvilinear prototypes. (Right) Distribution patterns of the strands and their corresponding models going from 1 to 7, 1 to 10, 1 to 14, 1 to 18 using a wooden frame with 56 holes and two extra ones for division of the rope at the ends of the single s-curvilinear frame.

Shift 1 to 7 1

Shift 1 to 10

1 2 3 4 5 6 7 8 9 10 11 12 1314 15 16 17 18 19 20 21 22 23 24 25 26 2728 2930 31 32 3334 35 36 37 38 394041 4243 44 4546 47 48 4950 5152 5354 5556

1 2 3 4 5 6 7 8 9 10 11 12 1314 1516 17 18 19 2021 22 23 2425 26 2728 2930 31 32333435 36 37 38 394041 4243 44 4546 47 48 4950 5152 5354 5556

Shift 1 to 14 1

Shift 1 to 18 1

1 2 3 4 5 6 7 8 9 10 11 12 1314 15 16 17 18 19 20 21 22 23 24 25 26 2728 2930 31 32 3334 35 36 37 38 3940 41 42 43 44 4546 47 48 49 50 51 52 53 54 55 56

Shift 1 to 7

Shift 1 to 14

Shift 1 to 18

By changing the shift, the strength and curvature of our models changed. The curvature (similar to a minimal net) is the main aspect to parameterize. It is important that when turning to architecture (second part of our study), we can predict how our building or model will change and which shapes can be generated. In architecture, it is not possible to make every time a model of the building to check whether the curvature is adequate. This is why it is important to have all the different curvatures mapped in Grasshopper. A chart or a catalogue is an easy way to tabulate measurements and to use these measurements for creating a parametric rule. The catalogue includes data for four different shifts, from the lowest to the highest shift.

Model with 56 holes and shift 1-->9 (18) 0 3 6 9 12 15 18 21 24 70 (1/2) 110 51 46 56 72 85 89 80 30 35(1/4) 110 48 43 55 75 87 92 84 30 Model with 56 holes and shift 1-->7(14)/ second measure 0 3 6 9 12 15 18 21 24 70 (1/2) 110 46 43 55 77 93 96 84 30 35(1/4) 110 43 40 54 80 95 99 88 30 Model with 56 holes and shift 1-->5(10) 0 3 6 9 12 15 18 21 24 70 (1/2) 110 41 40 54 82 102 104 88 30 35(1/4) 110 38 37 53 85 104 107 92 30 Model with 56 holes and shift 1-->4(7) 0 3 6 9 12 15 18 21 24 70 (1/2) 110 38 37 53 86 108 109 91 30 35(1/4) 110 35 34 52 89 110 112 95 30

Graphs allow other representations of the measurements. They clearly show the lower the shift, the more extreme the curvature gets. Or the higher the shift, the more flatter the middle curvature gets. In both graphs we see that al the models more or less have the same turning point from concave to convex. This point will be very useful in further parameterization. Based on these observations we derived a formula to describe the curvature depending on the shift. This formula was further used to generate all the curvatures in our Grasshopper models. The advantage of the formula is that we also can use other shifts than the ones we tested, allowing more options. Additional information about the parametrization and digitalization can be found in the section ‘Parametrization’.

Height (mm)

Middle measurements 115 110 105 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25

1-->18 1-->14 1-->10 1-->7

1/4 or 3/4 measurements

Height (mm)

Above the chart with measurements (on the left page), one can see the plan of the frame superimposed with vertical lines. These lines represent the measuring points 0-3-6-9-1215-18-21-24. The start and the end points were the reference points. At every line we took two measurements, one in the middle (70mm) and one at a quarter (35mm) of the model. The measurement at one quarter will be the same as at three quarters due to symmetric properties (which is the case only when using two identical frames).

115 110 105 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25

1-->18 1-->14 1-->10 1-->7

Shift

Curve Curveheight Heigh t

1-7

1-10

1-14

1-18

109 109

104 104

94 96

Density Densit y

Strongness Strength Flexibility Flexibilit y

The diagram above illustrates the conclusions made from the four single s-curvilinear shape prototypes each with a different shift. By changing the shift, the curve is changing, as well as the density. The higher the shift, the more expressed the hyperbolic curve, the stronger and the denser the structure and the less flexible the prototype becomes. The hyperbolic curve thus influences the strength and the flexibility of the structure. In the next research process we discovered that by bending the single, double and triple s-curvilinear prototypes, we could detect stronger elements. These are indicated by the red squares in the catalogue shown on the next pages. This higher strength is due a.o. to the more pronounced convex and concave shapes created by the bending. More specific: on the bending point in these elements, the hyperbolic curve is more expressed.

Open shape: first experiments • Push - pull movements • Assessment of strength

Weaving effects upon moving the middle frame: by moving up or down, and/or twisting the middle frame, new concave and convex curvatures with smaller or larger voids are formed.

Weaving Borders Strong Strong movement

Winding No borders Weak Little movement

Winding Borders Strong Strong movement

Weaving Changing direction of the middle frame to weave. No border in the middle, only at the ends.

Schift 14

Final model (December 2015): The model and its qualities can be summarized as followed:

The main questions arrising from this model were:

Spatial qualities are created by the use of ‘building blocks’ (such as an inner courtyard or hanging parts) by the use of only 3 different s-curvilinear frames: a single, double and the triple one (see p.77).

Will the system be composed of building blocks connected to each other or will it be conintuous woven and how?

Depending on the curvilinear fame used, another shape is created by bending, as shown on the right page. The resulting ‘triple s-curve shape’ which more specifically corresponds to a ‘three-void shape’, shows more opportunities to build on top. In the model, there are different densities, depending on the used shifts for the building blocks. The higher the shift, the denser the building block is. All the elements include as pattern the plain weave; which gives the elements structural qualities due to the interlacing. The created concave and convex shapes give strength to the elements. Each element has a woven frame, which reinforces the structural capacity of each separated element.

How to create a continous pattern from one shape to the other?

Final model (December 2015) including two- and three-void shapes, achieved by bending the s-curvilinear shapes.

Continuous weaving and connections Research was performed on different kind of intermediate pieces: double strings single strings border without border crossing straight weaving curved mold Based on these tests, we are able to conclude that intermediate pieces using borders are stronger; Subsequently we found that the problem solves itself by the use of a structural beam.

Examples, using different connections and borders.

Diagrams of possibile intermediate connections.

Closed form

Bending Open form

closed frame

closed form

112 holes (2 x 56) 112 strands 140 mm height length = length open form

Concave - convex

As shown in the image above, we can observe the evolution of the form-finding process. An open form was created as to allow more possibilities to create new shapes. By bending the open form into different shapes, a stronger closed form was discovered, due to its convex and concave shape. Closed prototypes were reconstructed by using a two- and three-voided frames (above the two-voided closed frame is shown). These closed prototypes achieved by bending into a closed two-voided or three-voided shape, maintained the characteristics of the earlier obtained concave and convex shapes of the open s-curvilinear prototypes. 79

Parameterization a) Height:

Height = 2 y, shift 14 The curvature of the created hyperbolic curve stays the same. However, the density is reduced.

Y 2Y

b) Radius (same shift): (R45, R55, R65) The bigger the radius, the less explicit is the hyperbolic curve. The density remains the same.

c) Two different radii: The hyperbolic curve is no longer in the middle, but moves to the smaller radius. The image below illustrates the relation between elements with a different radius. When the radii of the voids are changed, the length of the shape is kept and the relation between the inner circle and the outer circle stays the same.

R 55 to R 65 x>y

R 65

R 55 c1

x c2

Length 80

y =

Average c1 & c2 = 65

Length

R 45 mm =x1

R 55mm = x2

R 65 mm = x3

d) Quantity of wires: The more wires distributed over the same distance, the denser and the stronger the structure becomes. This should be taken into account for the view. The denser, the lower the porosity and the less the visibility become. There is no influence on the hyperbolic curve.

e) Changing the shift: The higher the shift, the stronger and denser the structure becomes. The hyperbolic curve is more explicit, the higher the shift. The more explicit the hyperbolic curve is, the stronger the shape becomes.

# Strings 2x36

1 2 3

# Strings 2x56

1 23 4 5 6

# Strings 2x86

1 2 3 4 5 6 7 8 9 10 11 12 12 13 14 15 16 17

Distance= X

Shift 14 u

space shape

convex - concave strength

density - pravacy -view strength

f) Change of shift and strands

Strings

Shift

Note in the last diagram that where the shift is changed in the structure, the density becomes lower and the structure less strong. This further motivates the step-bystep approach and can be solved by adding a string on top (which means thickening the material in this part of the structure).

Shift

Shift and quantity of strings

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Changing shifts, creates a hole.

Solution to deal with the gap.

Solution to prevent holes/ openings.

By changing the quantity of strings within one prototype, no problems were detected. Yet by changing the shift within a single prototype, problems of holes emerged. The diagrams down the page explain how to prevent these holes: the holes can be prevented by changing the shift step by step (not abruptly as shown in the first diagram).

g) Double skin

Advantages:

Research was done to create a double skin, as shown in the image below. These layers can create different kind of functions as will be further discussed.

A double skin can be very useful. If the outer skin is open and oriented in the direction of the south, climbing plants can grow. The leaves of the plants are able to protect the inner rooms from direct sunlight in the summer and they will fall in the winter to let in the lower sun beams into the room

By using layers, also three spaces are created: an inner, in-between, and outer space.

Additionally, the second structure can filter the polluted air from the environment. Working with two layers also gives the opportunity to improve the ventilation system, as further discussed in the chapter ‘Responsive systems’. At last a second skin can be a big advantage for cladding. For example, it can just be a straight skin as shown in image of the prototype. The holes are regular and the cladding can be standardized.

Double skin +

Nature

h) Directionality of the system: The system W.E.F.T. offers different possibilities of directional growth in the x, y and z directions by using different kinds of shapes.

Conclusion Through the first process of form finding using curvilinear weaving, we found structural capacities due to the interlacing by weaving, the hyperbolic curve (which is a shape which guides the forces) and the quantity of strings. The use of a curvilinear frame gives rise to concave and convex shapes in the prototypes, with a particular strength due to the hyperbolic curve. The height has no influence on the hyperbolic curvature, yet it affects the density and so the strength. The bigger the radius, the more explicit the hyperbolic curve becomes. By changing the shift, some weaker parts are created, which can be solved by thickening the material. Working with double layers can add beneficial features to the system by creating for example special ventilation systems, as will be further exploited in this research. This process of form finding lets us understand the structural capacities of weaving in a curvilinear frame.

We thank Iñaki Bedia for his contribution to this chapter. 87

Responsive systems Introduction examples and analysis W . E . F . T . a responsive system

Responsive systems A responsive system is able to react and adapt to a living environment by taking data of this environment. It are systems that feel, observe, listen, react, learn and interact. Before going on with analysing our system as a responsive system, we analysed the state of art in responsive pavilions and how to evaluate them. Take data → process data → Response

Warped (2008) Omar Khan This embedded responsive system designed by Omar Khan is made of pieces of plywood, responding to changes in the environment by twisting and bending between open and closed conditions.1 By changing directionality of the wood grain, Khan reaches different actions of each element joined by a connection piece. In this system, the humidity sensor, which is evoking the twisting, is contained by the material itself. It means that the responsive capacity is determined by the structure of the material itself. This system doesn’t need supply of external energy nor any kind of mechanical or electronic control. We can classify this system as a zero energy consumption system. This natural system opens a way to truly ecologically embedded architecture in constant interaction with its environment. Humidity → Change shape of elements → Global change

WARPED, By Omar Khan.1 1. Retrieved from: http://cast.b-ap. net/reflexivearchitecturemachines/warped/ [Accessed 15 January 2016]

FAZ Pavilion (Frankfurt, 2010) Achim Menges, Steffan Reichart and Scheffler + Partner

2. Material capacity, p.53-59, In: ‘Material computation’, Achim Menges, AD Architectral Design March/April 2012, Vol. 82 (2), p. 1-144

The FAZ summer pavilion built in 2010 on the northern embankment of the river Main in Frankfurt’s city center provides an interior extension of the popular public space. 2

3. Ecological urban architecture: qualitative approaches to sustainability, materially informed computational design in ecological architecture, Thomas Schröpfer, Basel: Birkhäuser, 2012, p.66-68

The pavilion is based on an integral structural and hygroscopic responsive system. This system evokes a reaction to weather changes. The surface of the elements will be fully opened (see picture below) when it is a sunny or dry day with a low humidity level.2 When the rainfall approaches and relative humidity increases, the pavilion elements are closing to form a rain screen. This is because the humidity triggers an autonomous response.2

Hygroscopic behaviour: refers to the capacity of the substance, in this case wood, to take moisture from the atmosphere when dry and to yield moisture to the atmosphere when wet.

When the rain stops, the humidity drops and the elements are opening again. The changing pavilion, in constant feedback and interaction, embodies the capacity to sense, actuate and regulate, this all within the material itself.1 This responsive characteristic is engrained in the material’s hygroscopic behaviour and anisotropic (directional dependence) properties.3,2

Breadboard deformation.4

4. Retrieved from: http://www.dbz.de/ imgs/39812413_e5fbf1eccc.jpg [Accessed 15 January 2016] 5. Retrieved from: http://www.achimmenges.net/?p=4967 [Accessed 15 January 2016]

FAZ Pavilion: Opening state in good weather.5 91

The desorption (removal) of water by natural evaporation reduces the distances between microfibrils in the cell tissue resulting in a substantial increase in strength due to the interfibrillar binding and an overall dimension decrease. 3,2 Wood has a constant dimensional movement because it continuously responds to changes in the surrounding relative humidity by adjusting the bound water content within the cell walls.2 These changes of shrinking and swelling by adsorption and desorption of water are fully reversible. The shape changes are also related to the directionality of the grain in the layers of the plywood strips. Dimensional changes in the plywood along the longitudinal axis are negligible but the transversal movements are significant because of the microfibrils orientation in the dominant wall layer: they are orientated at a slight angle to the longitudinal axis of the cells. The veneer is combined in this project with another synthetic composite, to expand the linear dependency of swelling and shrinking, in order to achieve highly specific and diverse shape changes. Opposite geometrical response can be evoked by the same environmental changes (bending and straightening). Following parameters contribute to getting different shapes: 1) fibre directionality 2) layout of the composite 3) length-width-thickness ratio 4) geometry of the element 5) humidity control during the production phase. Relative humidity is also temperature-dependent. That’s why this pavilion is also thermal responsive: also when the temperature drops, the surfaces will close.

FAZ Pavilion: Closed state in bad weather.5

Topotransegrity - Non-Linear Responsive Environments (2016) Robert Neumayr Topotransegrity is project about responsive architecture that can be introduced in public spaces, challenging the long-held assumption about architecture as a passive arrangement. This project currently investigates networked ways that enable architecture itself to operate as an intelligent interface that connects spaces, users and performance criteria in real time , as well as integrates the impact of such spatial configurations on urban space and urban public life.6 It is a kinetic structure capable of various transformations from small-scale surface articulations to large surface deformations, which can generate temporary enclosures (private space), by constant evaluation of its surroundings. It also reconfigures according to these changing conditions. The changes are done by sensors’ input and output and are directly related to the specific event schedule of its environment. It drives the generic transformations, initiating and locating the deformations that control the access and the circulation within the public spaces, and generates small emergent temporary spaces, with host programmes related to ongoing events. Additionally, the structure allows different degrees of transparencies. The transformations are based on the response to the movements and behavioural patterns of the visitors within the structure: the visitors influence the size, orientation and development of the temporary enclosures, previously established by the program mode. Finally, it affects the orientation of the surface tiles, based on the positions and sizes of the visitor crowds. On a long-term basis, the paths and motion patterns chosen by individual users, are influencing the surface topography by indicating and levelling the most frequented parts. They define the actual width of circulation spaces, temporary level connections, entrance areas and thresholds according to the number of visitors at every point in time during the period of use.6

(Topotransegrity: (Top) Different generated transformations of the system;6 (Bottom) Spatial arrangement.7

6. Retrieved from: http://rhizome.org/ editorial/2006/apr/12/topotransegrity-non-linear-responsive-environments/ [Accessed 22 January 2016] 7. Retrieved from: http://www.unsquare.at/?p=165 [Accessed 22 January 2016]

Algae Canopy (Expo 2015) Claudio Pasquero and Marco Poletto Claudio Pasquero and Marco Poletto proposed at the expo Milano 2015 a biodigital architecture powered by organisms. It was presented as a vision, but later-on they built a small version of the Algae Canopy which is called the Algae Folly. They use a 3 layered EFTE cladding system enhanced with microalgae organisms. They use a CNC welding technique to get the cushions under stress and get a dynamic behaviour of the water that travels through it. The physical parameters are: the weather patterns , the human activity and the visitors’ movement. The sensors are the flows of energy, water and CO2 working.

Algea Canopy 8

When the sun shines, algae photosynthesize and grow, thus reducing the transparency of the canopy. The presence of people underneath the canopy will trigger electro valves to alter the speed of the algae flow and to create a differentiation across the space.

EFTE: Ethylene tetrafluoroethylene: fluorine based plastic polymer. High corrosion resistance, high strength over a wide temperature range, high melting temperature, chemical, electrical and high energy radiation resistance properties. Most of the time used as a cushion.

The Algae Canopy will produce oxygen equal to 4 hectare of woodland and equal to 150 kg of biomass per day.8

8. Algea Canopy and Algea Folly, Retrieved from: http://www.ecologicstudio.com [Accessed 15 January 2016]

Remarks: In this system, the only external consumption of energy comes from the electric volts measuring the visitors’ movements. Besides this source of energy, the algae emerge as energy source themselves. Controlling the algae production also requires energy. But if we compare what we gain with what we lose of energy, we have a positive energy building. Every day you have to ‘harvest’ the building to start over again, because once the algae are produced, they don’t disappear by themselves. But what is harvested is useful, namely biomass. What happens at night, is not very clear. Supposedly, the canopy doesn’t work… If we evaluate the differences between the Algae Canopy and the Algae Folly, we observe a large difference in how it looks in real time and on a render. So probably the designers of this system needed more techniques than they initially estimated.8

The working process of the canopy, triggered by people underneath.8

How to analyse and criticize a responsive system? There are different kinds of reactive systems. Responsive systems can be analysed as follows: - Is it a low-tech or high-tech system? - how much motors for the system? (each element or global?) - how are the elements connected? - What is the energy efficiency? - is the energy source inherent or/and external? - is energy needed for the motors/electronic devices to respond? (ex: parasite, Jordi Truco & ADDA, elements are connected) - is there zero energy consumption? (ex: FAD pavilion) - What are the production costs? - How much material is needed? - Is it ecologically produced?

The parasite: All the elements are connected. One movement evokes a movement in the whole shape. Retrieved from: http://www.elisava. net/en/studies/master-advanced-design-and-digital-architecture-mentionresearch [Accessed 10 January 2016]

- How acts the actuator in the project? - Does the system deal (efficiently) with a problem? - Which are the advantages that the system has for the environment or is it just aesthetic? - food - air filtration - light/shade - privacy - ventilation - ... - What defines the response of the system? - the environment - a computer (ex. hypo surface: the global shape is defined top down) - Is it a bottom-up or top-down system?

. . . . W E F T , a responsive system Our system is a responsive system that is able to react to an environment, this by taking data of the environment by sensors or via other ways, and by analysing and translating them into values which change specific related parameters of our system. These changing parameters of the system will generate a different configuration, depending on the data values used. Take data → Process data by sensors and translate them into values → Digital response in Rhino

Investigating the hyperboloid shape from our form-finding studies in architecure, we find the form back in cooling towers. The cooling towers designed by van Iterson (WWI) and executed by bureau Kuypers, are constructed in the form of a shell-type rational hyperbolic shape and are nowadays still using this shape.8 This hyperboloid was chosen because it is considered to have a beneficial effect on the supply and discharge of air used to cool the water (by accelerating the upward convective airflow). Moreover, the reinforcement can be installed without bends because the main reinforcement is parallel to the straight lines of the hyperboloid. It offers structural strength with a minimal use of material.8 In nature, ants similarly use the chimney effect to create a ventilation system depending on the environment, as to get comfort in the nest (see p. 33). 96

The principle translated into the grammar of our shape goes as follows: If the shape has a big corner radius there will be more airflow. The higer the shift, the more expressed the hyperbolic curve, the higher the speed, the more will be the cooling and ventilation. In the middle part, the temperature won’t be maintained. On the other hand, a shape with a low corner radius will have less airflow. The lower the shift, the lower the airspeed. There is no cooling and less ventilation. The middle part is bigger, so will keep the temperature inside. The differences in temperature between the interior and exterior parts of a building and between different regions (cool down and hot upper) create different pressures, resulting in air currents.9

Such systems thus can preserve energy and functions on the basis of sustainability principles by leading the desired wind to the interior spaces and by providing thermal comfort. 9 Wind is the provision of comfort in hot regions by creating a difference in pressure on the exterior walls, so regulating natural ventilation and interior air temperature of a building. The heat is driven out of the building.9 Such chimneys or better called wind towers would best be designed with their openings to the nice breeze of the see, to use a maximum of natural ventilation. There is always a shaft to enter the breeze and another one to let air passage out. 8. Natural draught cooling towers, I.Mungan, U. Wittek (eds), Francis and Taylor Group, 2004, p.12-13 (Left) Chimney effects on our system elements.

Chimney Effect

More cooling & ventilation

Higher speed (Higher shift )

More Airflow

Middle: keeps temp. inside r2

Lower speed (lower shift )

Less Airflow r2 < r1

Natural windflow Further study of the created curvilinear shapes led us to the benefits of their surfaces in guiding the wind. A rectilinear building blocks the natural energy, because at the sharp edges, such building is experiencing a lot of drag and cavity created in the opposite direction.10 ,11 A curvilinear building in contrast works along with nature and experiences a minimum amount of drag, as the flow of the wind is undisturbed.10

Our curvilinear W.E.F.T. system also allows a natural flow of the wind around the structure without causing drag or cavity. It controls the wind by guiding, deflecting and blocking it due to the two or three-voided shapes. A three-voided shape can deflect or block the wind. A two-voided shape can guide or block the wind. The system can also let pass the wind through the elements.

9. Wind tower, a natural cooling system in Iranian traditional architecture, P.S. Ghaemmaghami, M. Mahmoudi, Qazwin, Int. Conf. ‘Passive and Low Energy Cooling for the Built Environment’, Santorini, Greece, 2005 10. Organic architecture, Umang Shandilya, 2014, Retrieved from: http://www. slideshare.net/umangshandilya/organic-architecture-43059156 [Accessed 16 January 2016] 11. New organic architecture: The breaking wave, David Pearson, Gaya Books, London, UK, 2001 The images on the right show different wind . . . . trategies that can be used in the W E F T system to ensure that the wind can be used in an optimal manner, as to benefit from the wind as natural ventilation, nice breeze, cooling or heating element.

Airflow

Drag and Cavity Drag

Cavity

Airflow Airflow Airflow

WINDSTRATEGY Guiding

Deflecting

Blocking

Deflecting

Airflow Undisturbed

Entering inner courtyards

Airflow

Deflecting outside

Airflow Blocking in natural way Minimum drag/cavity

Blocking

Passing trough

For the wind strategy we used 3 parameters; - the shift - the quantity of strings - the quantity of voids.

Also the quantity of voids is changing the shape. The generation of different shapes is important to be able to apply different wind strategies such as blocking, guiding, deflecting, channelling, entering...

The shift changes the strength and the shape. The higher the shift, the stronger the structure becomes and the smoother the wind is guided: the shape in the middle is then closer to a curvilinear aircraft wing and there will be a minimum of drag. Strength will play an important role in regions with very strong winds, where the building should not be weakened by the wind. The more fibres, the stronger and the denser the structure. This means less view or more privacy if the cladding is transparent or an open structure.

Parameters

Aerofoil, the shape of the aircraft minimizes the drag in the most optimal way. 100

Diagram: the three different parameters who are defining the structural shape en the view of our system depending on the wind.

Use of the firefly plugin in Grasshopper together with sensors and Arduino. Firefly is a plugin which helps us reading the strength from the good and bad winds, which are coming from two different directions. Depending on the strength of the wind, the quantity of strings are adapted.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

sHIFT 22 1 -> 22

sHIFT 18 1 -> 18

sHIFT 14 1 -> 14

Part of the Arduino code.

Shift strength-shape

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

X 12

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

X 78

12 34

5 67

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

X 10

12 34 56 78

91 0 11 12 13 14 15 16 17 18

#strings

Strength - density

Voids shape

101

Final model (January 2016) This model example illustrates the control of the wind using the wind rose on the right. The icy north wind with a high speed (12m/s, blue arrows below) should not enter the courtyard. This wind is deflected on the first floor, as well as on the second and third floor.

The strength is also created by changing the shift. The higher the NNW shift, the stronger the structure NW becomes and the smoother the wind is guided: the shape is then closer to an WNW curvilinear aircraft wing in the middle and there will be a minimum of drag. W

NE ENE E SE SSE

SSW

SSE

m/s speed 12 10 8 6 4

Windrose conceived to demonstrate the system.

The density of fibres in this model is higher where there are stronger winds, this to gain strength and not to be weakened or to become unstable due to the wind.

102

WSW In conclusion, our system W.E.F.T. is a responsive system to the wind. WSW

The warmer south wind is welcome and let into the patio, it is a less strong wind (6m/s, yellow & brown arrows).

Level 1

Topview model

Model

Level2

Level3

We thank Iñaki Bedia for his contribution to this chapter. 103

104

abiotic architecture

105

106

Growth capacities Graph Theory Directionality Continuous growth: roof & door Parametric definition

107

Growth capacities This chapter expands on the shape possibilities of the system. We discovered that our system can always consist of one basic element, which consists of two circles with two bi-arcs in-between. The two-dimensional representation of our system could just be created by nodes and vertices such as in graphs, therefore some graph theory was studied. Subsequently, we explain how a basic element of our model is parameterized in 3D and how this basic element serves to build up the more complex configuration of the whole self-generating system.

Graph theory At first, we will talk in specific about graph theory and its use in architecture. In fact, graph theory is a branch of mathematics. It is the study of graphs, which are mathematical structures used to model pairwise relations between objects. It was developed by Leonard Euler and is used in a lot of fields like computers science. 1 A graph is a representation of a set of objects where some pairs of objects are connected by links.

Conceptually, a graph is formed by vertices V (nodes or points) which are connected by edges E (lines or arcs). The vertices are labelled by numbers (1,2,3…) or letters (s,t,u… or v1,v2…). Every element can occur more than once, it has multiplicity.2,3 .

|V(G)| is the number of vertices V in a graph G, |E(G)| the number of edges. For example, for the image below we could write:³ V={v1,…,v5} for the vertices E= {(v1,v2);(v2,v5);(v5,v5);(v5,v4) ;(v5,v4)} for the edges |V(G)|= 5 |E(G)|= 5

Graph G= (V,E) example V={v1,…,v5} and E={e1,e2,e3,e4,e5} The graph has a circuit from v5 to v4, you don’t have to back-track; e5 and e4 are multiple edges; e3 is a loop 3

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REMARK the edges could also be labeld by letters (e1,e2,e3…) so E={e1,e2,e3,e4,e5} or by numbers (1,2,3..) so E={1,2,3} The edges (v4,v5) and (v5, v4) are the same.

In architectural design, graph theory is used to solve problems by developing models: these models are mostly used in the initial stage of design. The idea of using graphs for architectural problems was introduced by Levin. Graph theory enables a selective visualisation of only the essential characteristics to solve the problem.4 The easiest way to transform a plan into a graph is by defining the vertices and the edges. The vertices are seen as the intersections of walls and the edges as the walls between two intersections .

Architectural plan

Maintains only the relation between 2 walls

Coloured adjency graph Maintains the relation between 2 walls and contains the information about direction (red-black)

Coloured adjency graph

Maintains the relation between 2 walls and contains the information about direction and the weight (numbers)

Subgraph representing cells in the x-direction

Subgraph representing cells in the y-direction

Passage graph

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As shown on page 107, graphs can include different kinds of information depending on the type: - The relations between the walls: which walls meet each other. (This can also be represented by a matrix or adjacency list.) - Data about the direction (in an orthogonal grid) by represeting the direction of the walls by colours for the x and y direction of the walls [ = a coloured graph]. - Data of the dimensions of the edges, represented by weight of the edges [=(coloured) weighted graph]. The edge could also be seen as connecting two vertices describing the two parallel walls of the same cell [= a disconnected graph] . Some examples are discussed in this section.

a. London underground The London underground map designed by Harry Beck in 1933 of London is a graph example. Harry Beck simplified a complicated network, where people lost the way, to a simple and clear network by distorting the distances. The vertices are the stations and the lines ‘the edges’ are joining them. It is possible to travel from any station to any other.

2. Graphs, Retrieved from: https:// en.wikipedia.org/wiki/Graph_%28discrete_ mathematics%29 [Accessed 22 February 2016] 3. Graph theory, Keijo Ruohonen, ITranslation by Janne Tamminen, Kung-Chung Lee and Robert Piché, 2013, http://math.tut. fi/~ruohonen/GT_English.pdf 4. Algorithms in graph theory and their use for solving problems in architectural design J Roth and R Hashimshony. Computer-Aided Design 20 Issue 7, Sept. 1988, p.373 - 381

It is a graph in one piece: any two related vertices are connected by a path. It is a connected graph. Interchanges are shown different lines connect.

where

In the case of the London underground, the distortion of the distances don’t matter because the traveller is interested in the connections. This means that he wants to know that there is a line from station A to B rather than the shape of that line. This is different from when you go walking in de Pyrenees: In that case you want to see the sight, so you want to have a more detailed map and to know the paths’ shape and length. 5,6

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1. Graph theory, Retrieved from: https://en.wikipedia.org/wiki/Graph_theory [Accessed 22 February 2016]

Plan London underground.

b. Bridge problem Koningsberg

c. Voronoi Diagram

The Bridge problem of Koningsberg is a famous example. Koningsberg is divided into four parts by the river Pregel and these parts are connected by seven bridges. The problematic question when visiting Koningsberg is:

Voronoi is a cellular structure created by a field of points that is used to determine regions of space, or cells, that are closer to a certain point than any other point.

‘Is it possible to tour Koningsberg along a path that crossess every bridge once and at most once?’ 7 By using a drawn graph of the interconnection between the four parts in which the bridges are the edges and de four parts the vertices we can solve the problem. Crossing the bridge once, but not twice, is the same as finding a way to draw the graph without crossing a line twice. A tour like this doesn’t exist, there are two vertices less than edges.7

As the cells are not constrained by a fixed geometric topology, the cell properties can be tuned in much more specific ways than a tradition rectangular or hexagonal cell arrangement. The Voronoi diagram is the nearestneighbour map for a set of points. It is used as a tool to facilitate the translation and materialization of data from particle simulations and other point-based data into a volumetric form, which can easily be adapted to local changes. A Voronoi diagram can be made by throwing randomly a scattering of points, called sites. These points should be connected by lines to the point which is the closest. Then each of these lines should be bisected with a perpendicular in the middle. These last lines should then be connected into a network. 9

5 Introduction to graph theory, Robin J. Wilson. Longmann, Essex England, 1998 6. Topology underground, Irish Times 17 January 2013, Retrieved from: http:// thatsmaths.com/2013/01/17/topology-underground/ [Accessed 3 March 2016] 7. Bridges in Köningsberg, Mathigon Retrieved from: http://world.mathigon.org/ Graph_Theory [Accessed 3 March 2016] 8. Vonoroi diagrams: nature and architecture, Future concepts in architecture, 7 May 2011, Retrieved from: https://neoarchbeta.wordpress.com/tag/voronoi-diagrams/ [Accessed 3 March 2016] 10. The application of Voronoi diagram into the space planning for urban design, J. Park et al., March 2010, ISAIA 2008, p.524-528. Retrieved from: http://digiarchi.blogspot.com. es/2010/03/application-of-voronoi-diagram-into.html [Accessed 5 March 2016]

Map köningsberg translated into a graph7

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d) National Kaohsiung Performance Arts Centre, by Zaha Hadid

The information from the site conditions included trees, monuments, and boundaries. The access points of visitors are controlled by the Voronoi diagram. The region of the point clouds, which are created by analyzing the link and the relation between the space and the site, is connected to the main flow of human traffic so that it becomes a means to control the traffic of the space.9 The deformation of visual data drawn from the Voronoi diagram is also applied to the design of the canopy, façade, and roof of the building itself. 10

e) Fingerprint recognition Fingerprints have three characteristics: - there are no fingerprints the same in the world - fingerprints are unchangeable - fingerprints are one of the unique features for identifaction systems.

Progess of designing the site and the plan of the National Kaosiung Performance Art Centre 11

The lines that flow in various patterns are called ‘Ridges’ and the space between them are called’ Valleys’.

The competition entry for the National Kaohsiung Performance Arts Centre, designed by Zaha Hadid, used the Voronoi diagram for the analysis of the relationships of the data from the surrounding environment and the site.

Every form has a pattern, or types of pattern by itself. In fingerprints, although they are unique, we see different patterns occurring. The images shows some of these patterns.

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The places at which the ridges intersect or ends are called ‘Minute’, the places where the ridges form a half circle, ‘Core’ and the places where the ridges form a triangle, ‘Delta’. Parameters in fingerprints

In the past, people took fingerprints of a suspect and started matching them with a database to find the user identity. Because of the recognised patterns, we can divide the database in subsystems and already start with a classification, which makes it easier to find the user identity.12

Method for fingerprint recognition12

The fingerprint is segmented in different parts with different collours and a graph appears by connecting the segments together. From that graph, one can see in which subcategory the fingerprint is situated. Together by adding weight and the vertices, one comes to classification of the fingerprint. 11

11. Zaha Hadid, Retrieved from: http:// architect-1.blogspot.com.es/2014/09/national-kaohsiung-performing-arts.html [Accessed 5 March 2016] 12. Application of graphs, Retrieved from: http://www.slideshare.net/Tech_MX/ applications-of-graphs [Accessed 5 March 2016]

Segmentation (arch, whorl, right loop and left loop)12

Conclusion: • Applying graph theory to a system means using a graph theoretic representation which is consisting of nodes connected by vertices. • Representing a problem as a graph can provide a different point of view. • Representing a problem as a graph can make a problem much simpler. More accurately, it can provide the appropriate tools for solving the problem. • Graph theory can help to represent a system in a more understandable way. • Each node and vertices can have some symbols as colours, numbers and letters. These symbols are giving a specific weight to the node and the vertices. These symbols can give to each node characteristics. In the following chapter our system will be translated into graphs: this will help us generate our system in an easier way, as further shown and explained in the chapter ‘W.E.F.T..a generative system?’. 113

Component & growth: After analysing graph theory and graph-related projects, we evaluated our system. We discovered that both the two-void and three-void elements consist of one basic element. This basic element is in fact just our two-void element. By rotating this element three times with an angle of 120 degrees you get basically our three-void shape.

To better describe our system and the relation of its elements, our system can be seen as a graph. Our system consists of circles which are the main activity rooms and which are defined by a node and their radius. Depending on the space needed for the activity, the circular room size can increase or decrease.

Node Rmin= 2 m Rmin= 10 m

The radius has a minimum size of 2 m and a maximum size of 10 m. The circles are connected by bi-arcs. Each circle can be connected with maximum four other circles.

Vertice

De distance between two nodes need to be an element of the domain [(R_ n+R_(n+1) )*1.2;(R_n+R_(n+1) )*2.1] so that the bi-arcs can be made.

120°

#Connections

# cONNECTIONs

Possible options for different numbers of connections (maximum four connections). 114

Mixed

Decomposition

Length connection d2

d1 x

Parameters of component

width of connection

area of space

п•r12

п•r22

п•r32

п•r42

d1 3x

s<t<u<v

п•r12 < п•r22 <п•r32 < п•r42

Parameters influencing the size of our system.

115

Continuity and directionality: In this stage of our research, continuous weaving was tested, as illustrated in the adjacent images. Growing possibilities in x, y and zdirections, such as the bridging of height and possibility to parasite, were tested. Additionally, the relationship with the ground was studied, by integrating the structural frame of our woven prototype into the floor.

Examples of continuity, parasiting, bridging of height and changing of x, y and z-directions.

116

We also invesitgated how to design the roof. Therefore we studied the use of a compression ring in a bycicle wheel and in yurts.

117

Compression rings Compression rings are a key part of a fast, convenient roof building system that can utilize locally available wood poles. A tensile-compression ring structure is derived from the spoke wheel principle.1

Bycicle wheel: structural capacity Wire wheels in specific bicycle wheels are prestressed structures, with builtin stresses that are reduced when they are subjected to loads. In order to work, the wires must be tensioned to prevent their buckling under load. With tension, wires can support compression loads up to the point where they become loose. The bottom spokes directly under the hub of a wire wheel become shorter under load, but instead of gaining in compression, they decrease or lose their tension. 1,2 Structurally the bottom spokes are acting as compression members in the wheel, they look rigid. This is because the individual spoke tension results from tension in all spokes. This means that the wheel can be analysed only by considering all of its spokes. The higher the pretension in the spokes, the more compression forces arise, the stronger and stiffer the wheel becomes. By using pretensioned spokes, the high level of tension prevents the spoke from buckling.2

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By pretensioning the spokes, the wheel possesses great strength for such little weight. Our roof is based on the same principle of forces. So imagine a bicycle wheel which is held horizontally so the inner cylinder is hold vertically, and that you push its rim inward with your hand. The rim will deflect inward at the place where you apply the force rather than elsewhere. Nothing changes at the other side of the wheel.1,2 So in short, when a tensile load acts on the ring, the ring becomes compressed and ring action arises. This principle can be applied for roof structures. The more ring action can be provided, the more efficient the roof structure will become and more material will be saved (so there will also be a lower cost). When using a double inner ring with columns under compression, an opening in the structure can be created at the central node: the inner ring will transfer the loads through the spokes to the outer ring. An efficient equilibrium is reached when the angle between the spokes and ring elements in the outer and inner ring are equal to each other; so, there will be no loss of material.1,2

Load affected zone at the bottom of a wheel: due to the tensile-compression ring structure, nothing changes at the other side of the wheel.1

1. Tensile-compression ring: A study for football stadia roof structures, I. Boom, TU Delft, April 2012, p.7 2. The bicycle wheel, Jobst Brandst, Avocet. Inc, Palo Alto, California, 1993, p.6-13 3. Reciprocal frame architecture, Olga Popovic Larsen, Elsevier Architectural Press, Oxford, UK, 2008 4. Yurts: Living in the round, Becky Kemery, Gibbs Smith Publisher, Layton, Utah, 2006 5. Yurts, Retrieved from: http://www. wikiwand.com/en/Yurt [Accessed 7 June 2016] 6. Roof from the velodrome, Berlin, Retrieved from https://es.pinterest.com/pin/ 184436547214005889/ [Accessed 7 June 2016] 7. Cycling stadium in Berlin. In ’In detail: building skins’, Christian Schittich, Germany, 2006, p.86-88

Reciprocal roof

Examples:

Cycling stadium Berlin

A reciprocal frame is a grillage structure in three dimensions used for a roof, consisting of mutually supporting sloping beams, placed in a closed circuit. The inner end beam rests on and is supported by the adjacent beam. At the other end, the beams are supported by an external wall, a ring beam or columns. The beams are placed tangently and they form an inner polygon. The outer ends form an outer polygon or circle.3

Yurt roofs

The building of the cycling stadium in Berlin is composed of a circular steel roof 142 m in diameter and 48 trussed girders in radial arrangement. In combination with the bracing ring girders, the steel construction forms a massive wheel that is supported on 16 concrete columns at it main ring girder. These structure is clad with a metal mesh, like used in its façade.

Different sizes of the innercircle created by the construction of a reciprocal roof.3

The roof of a yurt is cone-shaped and supported by beams which are meeting in the centre ring. Various forces operate on a yurt roof. The gravity pulls down on the roof beams, creating an outward thrust against the outer wall and a force of compression against the inner ring. The roof beams are held in a state of tension between the compression ring at the centre and the tension band at the top of the wall. The centre ring holds the beams in a state of compression. This is giving the yurt roof its strength and flexibility. Because of this combination of a central compression ring and lower located tension band (where the roof meets the wall), long roof spans are possible without any other supporting system.

Roof from the velodrome, Berlin.6

The skeleton of the yurt.5

The forces acting on a yurt.4

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Roof

A compression ring for W.E.F.T. .

The roof structure of W.E.F.T. incorporates a unique architectural design that has its origins in the mountain steppes of Central Asia, in which the beams of the roof are meeting in a centre ring, producing inward and outward pressure. This holds the roof in a state of compression just as in a bicycle wheel.

Roof reasearch: prototypes.

Effect on the wind Not only the curvilinear shape of our system lets the wind waves moving naturally around the building, rather than getting caught at (and potentially ripping off) corners. But also the rounded roof avoids ‘air-planing’ - a situation where a strong wind lifts the roof structure up and off the building. 8

8. Why our ancestors built round houses and why it still makes sense to build round structures today, Retrieved from: http://inhabitat.com/whyour-ancestors-built-round-houses-and-why-it-stillmakes-sense-to-build-round-structures-today/ [Accessed 7 June 2016] 120

Digital model of the roof.

Doors The incorporation of the door in the system tectonics needed some investigation. Two options where studied: One was generating bigger openings by changing the shift. In these tests, we could observe that there exist weaker parts (picture on the right). This is also demonstrated in the pattern on the right. It is clear that there is almost no interlacing at the site were the opening is created. Moreover, the hyperbolic curve disappeared. The second test was by changing the flat circular beam into a beam with a door incorporated. In the ‘rapid’ prototype (left image) as well as in the pattern drawing, we could observe that the interlacing still takes place and that there will be more structural quality than just by changing the shift.

Door research: rapid prototypes by shift change (Left) and beam incorporation (Right) and their corresponding weaving patterns (top, bottom, respectively).

121

Parametrization We already parameterized the surface, created by weaving, in the chapter: Form Finding. There we also discussed the initial parameters. During our further research, some parameters will be fixed, while some new will arise. In this part we will describe, how we create the form of our system digitally. Furthermore, we will describe how our system is capable of self-organizing guided by the environment (see chapter ‘System, site, contextualization’). To show how the shape of the system is made, we will describe it with three circles instead of explaining the whole configuration. The approach to the system is similar, only you have more circles and more connections, so it becomes more complex.

The initial parameters were: • The shift: this is a horizontal displacement, that changes the density and porosity of the system • The strings: this is an amount of threads that changes the density and porosity of the system: together with the shift, it gives the structural strength to the shape. • The radius: the radius defines the size of a specific room or program. The domain of the radii of the system is fixed after one has insight in the program. • The height: this is the height of a room and is depending on the function of the space.

122

New parameters identiefid after the study of graph theory and growth capacities: • Distance between circles: to create the bi-arcs, we are bound to limits in distance between the center points of the circles. • Opening angles: these angles make the openings between the circles and the bi-arcs. The bigger the openings, the greater the relation between the adjacent rooms. • Space between bi-arcs: the space needed between the bi-arcs can be chosen depending on the flux of people or the relation between the rooms.

Zoom of the components of the right image above.

Circles We start with placing the center points of the circle. This can be done manually or by the self-organization, as explained further. It is possible to choose or to adapt the radii to create better spaces, although these radii are determined by the program and the areas needed for every room, so small changes can always happen. Two types of referencing the start.

Determination of connections Every circle can connect to maximum four other circles, otherwise the opening angles are getting too small to create the bi-arcs. Depending on how many connections a circle will have, we need to calculate the opening angle. We saw that we need at least an opening of 40 degrees, because otherwise the bi-arc will not work. Our maximum is four connections, that’s why we set the maximum angle on 90 degrees. It is important that the lines of the bi-arcs aren’t intersecting. As for the distance, we created a formula to calculate a domain for every opening angle depending on the amount of connections. The greater the angle the better the bi-arc, although this is not always in accordance with the program. By doing a digital form-finding process, we saw that the creation of the bi-arc is also restricted to the distances between the center points of the circles. The bi-arc is not only depending on the distance, but also depending on the radius and the opening angle. The bigger the radius and the opening angle of both circles, the bigger the distance can become. For this we created a formula which gives us each time the domain of the distances. Firstly, we used this to check whether it was possible to create the connection, afterwards we embedded this in the self-organization part. Components for calculation of distance and angles.

123

Creation of bi-arc To create the bi-arc, we use the center points of both circles and the output of the previous part. Also we can choose how open the bi-arc will be in the middle. The more circles and connections you have, obviously the more complex the creation of the system gets. On the left, the images illustrate how the bi-arcs of our system are created. Distance and creation openings angles room 1 and 2.

Bi-arc Creation with different distances in the middle.

Adding the amount of strings Basically our system is fully created in plan after aplying this step. The amount of strings will determine the porosity and strength of our system. To control the amount of strings and to guaranty the continuity of the strings, we created three types of porosities. The most important is that the distance between the strings is everywhere the same; 0.5m or 1m. This is important for the continuity of the strings, so that every point will be at the same place at the next level. The amount of strings is determined by the circumference of the circles and the distance of the biarcs. Before adding the strings, some parts of the circles have to be deleted, to create a fluent form with the bi-arcs.

Shape with different porosities. 124

shift 8

shift 10

shift 12

Strings 0.5 m double use Strings 1m double use Strings 1m Single use Graphic of the porosities and the most used shifts.

3D Surface To grow in the vertical direction, there are different possibilities. We can grow vertically with a horizontal displacement of the levels because of the self-organization. The radius of the next levels can change, depending on whether less/more space is needed. Most of the time, it will be only a vertical displacement with height as parameter. For each next level or ceiling, the shape of the system has to be created. The formula and derivations to be used have been explained in the chapter ‘Site, system, contextualisation’. Moreover, a middle curve between two levels is created in order to apply the convex and concave changes. Creation between points for concave and convex deformation.

125

Creation of the surface.

Strings Every circle and bi-arc may need a different shift because of strength or demanded porosity. So we determine for every circle and bi-arc separately the deformation and afterwards we combine them together to create the surface where the strings will be. On this surface we will project the strings, this is done with geodesic curves. We used this component because it searchs the shortest path between the points, and this is exactly what happens when we weave and tension it up. A shift change’ in the same surface is achieved by skipping points above and below (see p.84). .

126

Strings projected on the surface.

Density change by changing the shift.

Roof The roof is discussed in the previous section p.120--123 The principle of the bicycle wheel, more precisely a compression ring is used. For the parametrization it is important that the roof has half of the strings than the circle: this is because the strings come together in the same point. Also if we would use all points, the roof would be too dense and the roof’s compression ring can’t connect that many holes. By using two times every point, the string can come in and directly turn and move in the opposite direction. .

Larger configurations A complete configuration using the system (generated in the context of Vallcarca) will be worked out and explained in the next chapter. The example, we just explained in this chapter is a simple version of how to make the whole configuration. All the explained components are also used in the final configuration, only with more links and more circles. In the final configuration, you embed more than one level, but the principle remains the same. .

127

The file of the final configuration generated by the system for a specific context is vertically easy to read: every vertical line explains a step of the whole process starting with referencing the circles and ending with making the roofs.

Grasshopper whole configuration.

Topview whole configuration. 128

Perspective final configuration.

129

130

System, site, Contextualization Data collection and study of Vallcarca Operative cartography Program distribution W . E . F . T . , a generative system ? 131

In this chapter, W.E.F.T. is generated through the specific landscape of Vallcarca, a neglected neighbourhood in Barcelona without a specific centre. Our system is creating a micro-centrality by fulfilling specific program demands (central uses and public amenities). Vallcarca is just one example. We have to keep in mind that the generated building in Vallcarca just is one of the many possibilities of our system. Our system has a high capacity of generating formal differentiation. The creation of form and space, using processes of self-organisation of material, allows us to see that the attained form is not the only one, it is only one of the many options our system is capable of. The purpose is to design a hybrid which designs the system capabilities in relation to the environment.

Vallcarca data collection Vallcarca is a valley surrounded by three hills, some of which still retain part of natural space. Originally Vallcarca was written Vall carcara which means “squeezed”. So, a neighbourhood squeezed between the Valley Putxet and Coll, where once circulated the river Riera de Vallcarca, originating from Collserola. The neighbourhood of Vallcarca is situated on the slopes of the hill taking advantage, since its founding in the late nineteenth century, of the virtues of waterways, natural springs, abundant mines and sources of the area.

6. Carregades de Raons, Assemblea de Vallcarca, 2016 7.

Retrieved from: https://www.goog-

le.es/maps [Accessed 1 May 2016]

Location of Vallcarca in Barcelona.7 132

This natural richness defines from late nineteenth century onwards, the peculiar architecture and urban form. The first urban settlements were located around Torrent de Farigola (c.Farigola), later following la Riera Vallcarca (Av. Vallcarca), taking advantage of the wealth of the fertilized ground by water to install orchards and gardens.6,p.9 These spaces, now used as patios and terraces, form one of the most important green heritages of the area. Little patios with vegetation tell us what Vallcarca was, it reminds us of the existing rivers before they were channeled. It is common for historic buildings to give back to the streets while facing with their facades the patios or terraces. 6(p.10) The plots, long and narrow streets, the wealth of facades, different heights, alignments, colors and textures correspond to the traditional shapes and make up Vallcarca landscape, as they have done for over a century.

Old Vallcarca.

In 1975, Vallcarca was affected by the project of la via “U”, a street who connects Gracia with Colleserola. These project was finally rejected. This urban framework causes a social degradation. In 1976, the Plan General Metropolitano (PGM) declared the zone of Vallcarca as a zone for interior renovation. This freezes the daily improvement of local homes and buildings, waiting for the completion of the municipal renovation plan. The long process of indeterminacy and lack of municipal investment have played against its residents, but the completion of the renovation plan was the beginning of the end of Old Vallcarca. It is in 2002 that the neighbourhood of Vallcarca started to suffer from the approval of the Modification of the General Metropolitan Plan of Barcelona, so 26 years later than the PMG.

Vallcarca nowadays: ‘dirty lot’.

The old buildings that made the old center of Vallcarca are disappearing and are making place for a denser and alienated character. New roads, streets, boulevards houses and really high buildings are created and the old buildings are demolished. Inhabitants were forced to leave the historical center. Most of the shops and factories who made the neighbourhood living have disappeared and are now empty dirty lots. On these lots you see people separating metal in fire, that was taken out of the waste in the streets.

Vallcarca nowadays: ‘dirty lot’.

133

The demolition of these buildings is equal to the oblivion of what differentiated and identified the neighbourhood from the moment of his birth. Not only historical buildings where demolished but also natural sources such as the Source ‘Nina’ (under the viaduct Vallcarca) sprouting “water with healing properties” and the wells on the square ‘Tomillo’ have disappeared. Some old holiday houses are still preserved, whether or not with or without a garden and are giving the neighbourhood a melancholic character. A lot of organisations and associations are working on improving the district by understanding and modifying the process of degradation, creating new identities by filling the lots with squares, gardens … The gardens and the permeable sun panels reclaimed by the neighbourhood associations remind us of the melancholic character and how the old Vallcarca still is alive in the memories of the neighbourhood.

Souvenir shop.

Study of the site After studying the history of Vallcarca, a global study was made of the neighbourhood. Today, very noticeable as you wander around are the hilled landscapes, the graffiti of the activists, the souvenir shops related to Park Guëll, the old historical houses, the dirty plots and some local and neighbourhood shops which are concentrated in the ‘Farigola’ street. Important data we observed by wandering around we mapped in a plan such as the height differences, the parcels of opportunity (which are the empty dirty plots), the green zones (such as city parks and afforestation), the neighbourhood (such as a school), local (such as the pharmacy) and global-touristic activities and commerce.

Local shop.

The first perimeter in the map on the right is the global perimeter of the neighbourhood of Vallcarca in which the wind and view are studied The wind and the view are the two main elements of our sytem as mentioned in previous chapters because: - The quantity of strings is related to the strength as it is also to the view. - The configuration of the global shape of our building is related to the wind.

Ruin of an old house. 134

Operative cartography On the next page, the distance of view is analysed for each parcel of opportunity, which corresponds to the empty dirty plots and open public squares located in the perimeter of Vallcarca.

Map: Global analysis of the site, Parcel of opportunities, green zones and commercial zones (neighbourhood, local and global) are indicated. A global perimeter of Vallcarca is established. 122.3 117.8

117.8

The distance of view is mentioned in meters in different directions.

130

The first perimeter of analysis is established by the view areas, excluding the parcel with the least view.

120.3 155

160

151.2

126.3

150 104

120 145.6 108.6

135

111.8

115

140

145

130 103.7

gLOBAL ANALYSIS

115

102.6

110

105.1

125 105 100.5 101.8

90.8 120

pARCEL OF OPPORTUNITY

113.6 99.5 121.8 115

gREEN ZONES

117.8 110

nEIGHBOURHOUD 97.5 105

lOCAL

40 (m)

90.3

gLOBAL_tOURISM gLOBAL PERIMETER

100

Scale 1:200 LEGEND Parcel of opportunity

Commerce Neighbourhood

Green zones

Local Global tourism

Neighbourhood school. 135

56 85

114 141

131

distance of view in a specific direction

170

80-100% 60-80% 40-60% 20-60% 0-20% Scale 1:1000

1sth perimeter

136

137

SSW wind End/ blocked wind

SSW wind outside the parcel Existing SSW wind into the parcel area Arriving of the wind into the perimeter zone Scale 1:1000

second perimeter

138

Windrose Barcelona

To define the next perimeters, the winds were studied. There are two main winds in Barcelona, the SSW wind and the NNW wind, as can be observed on the wind rose. In summer the SSW wind is an unpleasant hot wind, whereas the NNW wind a nice breeze. For the second perimeter, the SSW wind was analysed for each parcel in relation to the view. Only five parcels where left over: a little empty plot, the ‘dog park’, the ‘local gardens’, the ‘petanque area’ and a ‘big empty plot’. These plots don’t have a lot of SSW wind coming into the parcel or where this wind comes into the parcel, there is almost no view. For the last perimeter, the NNW wind was analysed. The perimeter includes all the places with NNW wind. Four plots were left over.

NNW wind NNW wind NNW wind

Arriving of the wind into the perimeter zone Arriving of the wind into the perimeter zone Arriving of the wind into the perimeter zone Existing NNW wind in the parcel area Existing NNW wind in the parcel area Existing NNW wind in the parcel area NNW wind outside the parcel NNW wind outside the parcel NNW wind outside the parcel End/ blocked wind End/ blocked wind End/ blocked wind Third perimeter Scale 1:1000 Third perimeter Third perimeter

Scale 1:1000 Scale 1:1000

Windrose Barcelona

N 139

Spatial proposal After analysing Vallcarca a first attempt was made of massing (see the left images, and the maps on the next pages). By manual application of the grammar rules (see p.141) which are based on good (NNW wind) and bad winds (SSW wind) (see page on the left), a first configuration was made. In this first configuration, we can observe that the NNW wind is guided through the whole perimeter and SSW wind is blocked, as desired. The densities are changing depending of the view and privacy needed. Deflecting and no view has a higher density in strings than deflecting and view. The quantity of strings in the grammar rule image on the right is represented by + and -. Depending on how much levels are placed on top of a room, the shift will be changed and another hyperbolic curve will be created, which will lead to more or less strength and more or less view. Massing models: - Wind lines (Top, Left). - Environment model including the projection of the view map of this specific plot. (Top, Right). - Massing model over the whole perimeter (Middle). Translation of the view map of a specific plot into points with different heights for the CNC and to enable creation of the model of the specific plot in the upper image on the right. 140

Grammar rules related to the wind: As earlier mentioned in the chapter of responsive architecture, our system is responsive to the wind as well as to the view. It can deflect, block, channel, enclose, guide and even increase the intensity of the wind.

Detail of massing model.

141

evel 1

Floor 2

density Lowest

Highest

D INTERVENTION

no view view 2 floors 3 floors ORIGINAL WIND

Lowest

Floor 1 Highest WIND INTERVENTION

no view view 2 floors 3 floors

Floor 2

ORIGINAL WIND

ssw wind

NnW wind

142 NnW wind

NnW wind

NnW1:1000 wind Scale

Scale 1:1000

Floor 1 density Lowest

Highest

oor 3

WIND INTERVENTION

y Lowest

Highest

no view view 2 floors 3 floors

NTERVENTION

ORIGINAL WIND

sw wind

ssw wind

nW wind

NnW wind

Floor 3

Scale 1:1000

no view view 2 floors 3 floors ORIGINAL WIND

ssw wind

NnW wind

143

NNW analysis domain [0:5]

144

SSW analysis domain [ -5;0]

View analysis domain [0,5]

NNW wind [0;5] +

View [0,5]

NNW wind + view [0,10]

SSW wind [-5,0] -

View [0,5]

SSW wind - view [ -10 ; 0]

145

Placing the rooms depening on the view and wind To place the centre point of each room/activity, each room got specific values for the NNW wind , SSW wind and view. (see Table p.148) The wind values for SSW and NNW wind are depending on the kind of wind ‘hot/unpleasant or agreeable’ and the quantity needed for ventilation, drying, odour regulation and other functions.

These coloured wind analyses maps are translated into other maps with readable values by using the image sampler in Grasshopper as shown in the images below and on the right.

A dynamic fluid analysis from the SSW and NNW needs to be done, to get an accurate result of the influence of both wind directions as shown on p.144.

The new generated maps of the SSW and the NNW winds are visual readable by the differentiation of density of the coloured points. In fact each point is a circle on a regular divided grid with a specific radius depending on the strength of the wind. These radius, which represents the strength of the wind, is remapped between a specific domain.

In each of these analyses, a different tone of colour is used depending on the strength and the quantity of the wind. Light blue means there is wind and yellow means there is a huge concentration of wind.

The NNW wind values are remapped in a domain between 0 and 5. The SSW values are mapped in a domain between -5 and 0. The view distance is also remapped in a domain between 0 and 5.

Translation of the view distance of the big empty plot into values using the image sampler of Grasshopper.

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At the end, the sum is made from the NNW wind and the view, and a subtraction for the SSW wind and the view: Domain NNW + view = [0,10] Domain SSW - view = [-10,0]

Page 142: (Top): Fluid dynamic analysis of the SSW (Left) and NNW winds (Middle) and a view analysis(Right), Viewmaps were constructed based on the distance one can see in each direction. (Bottom): Corresponding translations by the image sampler in Grasshopper into points: the denser the zone, the higher the concentration of the NNW or SSW wind or the farther the view. Page 143: Translations by image sampler in Grasshopper from the fluid dynamic analysis, illustrating two combinations of wind and view. The denser the zone, the higher concentration of NNW of SSW wind ‘and’ the farther the view.

Translation of the NNW wind map and the SSW wind map into values.

Translation of the NNW wind map and the SSW wind map into values, using the image sampler of Grasshopper.

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Function

Area (m²)

Radius (m)

SSW

NNW

View

SSW/ View

NNW/ View

floor

Rehearsel room

3.99

-2

Staging area

314

10.00

-4

-5

0&1

High ventilated offices

201

8.00

-3

1&2

Entrance/lobby

201

8.00

-1

-4

Library1

adult

112

5.97

-2

-4

Labrary2 youth

5.50

-2

-4

Library 3 children

5.50

-2

-4

Low ventilated (LV) workshop

3.57

-1

Wind sheltered terrace

3.57

-2

Leisuren room

3.57

-2

-5

Conference room

50.26

4.00

-2

-6

Workshops (different)

332

10.28

Exhibition rooms

3.99

-1

-2

Event bar

140

6.68

-1

-5

Covered outside

5.05

-3

Dry workshops

3.57

-4

High ventilated workshops

3.99

-1

-3

Open workshop

3.57

-2

View workshop

3.57

-2

-6

Dark workshops

3.57

-2

Inflow market

5.35

-2

Outflow market

5.35

-4

-6

Still market

5.35

-2

6 2 2

0 0 0

Table of program distribution and their corresponding values depending on the kind (agreeable, hotter, colder) and quantity of wind needed to ventilate, regulate odour, make energy and other functions. The colours are the linked rooms: such as the rehearsal room should be connected with the stage and the stage should be connected with the lobby.

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Stage STAGE

EXHIBITION ROOM Exhibition Room covered terrace Covered Terrace

1 + 1= 2

1+1= 2 -1 - 1 =-2

3+3=6

-4 - 1 =-5

0 - 3 =-3

2+3= 5 -1 - 3 =-4

3+4= 7 -1 - 4 =-5

Entrance / lobby Entrance/Lobby

2+0=2 -2 - 0 =-2

EventBar Eventbar

Rehearsel Rehearsel

Inflow market INflow Market

Outflow market Outflow Market

Library Library 1+2=3

2+2=4

0 - 2 =-2

-2 - 2 =-4

Terrace Terrace

4+2=2

4+2=6

-4 - 2 =-6

-0 - 2 =-2

0+2=2 0 - 2 =-2

INtermediate market Market Intermadiate 1+2=3 -1 - 2 =-3

LOwventilated Ventilated Workshop Low workshop Diagram of our program on level one (represents +- 50% of the total program) with the corresponding values of NNWV or SSWV).

Page 150-155: Generation of the first floor. Page 156: The final population. The red frame indicates the choosen configuration. Page 157: Generation of the second ant third floor.

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Radius : NNW+View Value : SSW + View Value : Links :

10m +2 -5 Rehearsel Lobby

The zones are displayed in the first image. Firstly, the biggest space is placed, which is for the Vallcarca Program the stage (314 m²). The absolute value of the sum from the SSW + Value (SSWV) is the biggest one. So the stage will be placed in a zone with the SSWV value equal to -5. Secondly, the centroids are calculated which are the midpoints of the circular room. Thirdly, the intersections of the rooms with the boundaries are searched. If the room is crossing over a boundary, this room is deleted. Only one option is left in this case. After placing the stage, the links are placed. The biggest linked room is the lobby. The same process is repeated but this time the NNWV value has the biggest value.

Radius : NNW+View Value : SSW + View Value : Link : 150

5m +5 -4 Stage

Now, in this stage, the length of the links are checked and if they are not crossing borders. All the links which are crossing borders or too long are deleted. Only one option is left. Subsequently, the next and last link of the stage is placed, the rehearsal room. The same process is done. Note that the SSWV and the NNWV values are the same.

Radius : NNW+View Value : SSW + View Value : Link :

3,99m +2 -2 Stage

There are three options to go on, so a population of solutions will be created. Only one of the options is explained. The next biggest room is selected: this is the event bar. The same process is applied for the event bar and its links.

Radius : NNW+View Value : SSW + View Value : Link :

6,68m +7 -5 Stage

The process is repeated until all rooms are placed. 151

Covered terrace Radius :5,05m NNWV: +7 SSWV : -5 Link : Event bar

152

Exhibiton Radius : 4m NNWV: +2 SSWV : -2 Link : Event bar

Library Radius : 5.5m NNWV: +4 SSWV : -4 Links : Terrace Low ventilated workshop

153

Low ventilated workshop

Radius : 3.57m NNWV: +3 SSWV : -3 Link : Library

Windsheltered terrace

Radius: 3.57m NNWV: +3 SSWV : -2 Link : Library

Flow market inflow Radius: 5.35m NNWV: +6 SSWV : -2 Link : Outflow 154

Flow market Intermediate Radius 5.35m NNWV: +2 SSWV : -2 Link : Outflow

Outflow Radius: 5.35m NNWV: +2 SSWV : -6 Link : Windstill

155

Option 1

Option 2

Option 3

Option 4

Option 5

Option 6

Option 7 156

Option 8

Option 9

Offices ( stage = 2 floors, library 2nd floor)

Dry workshop

Dark room

Open workshop

View workshop

High ventilated workshop

Wind links

Office

Leisure room 157

NNW wind SSW wind E Enclosing

Channeling/ guiding

Deflecting D

Courtyards

Metro connection

view courtyards The final decisions for programming are made by the mind of the architect. Important factors are the metro, the powering of the wind, the creation of courtyards and their view.

At the end we get a population. In this population the final decision is made by the mind of an architect. For the final decision, there should be checked: if there are interesting courtyards, each with a specific view; if the pleasant NNW wind is coming in the courtyards, by guiding or enclosing it, and if the hot irritating SSW wind is coming in, by deflecting or blocking it.

158

After input of these decisions, there is one solution left in this case. Yet, in other cases, it can be possible that two or more good solutions are left over, then one of them should be chosen. But in this case there was only one. Subsequently, some changes are introduced, to get more architectural values: 1. The lobby is moved a little bit to the north to be in a perfect line with the metro.

2. The flow market is reorganised to create a bigger courtyard, relating the stage, lobby and market. 3. An entrance is created, for an indoor staircase to go uphill, connecting the ‘Carrer de la Farigola’ with the ‘Carrer de la Mare de Déu de Coll’, for this reason the exhibition room was removed and placed into an existing building.

entrance links

Library area event area staging area market area

Event plaza chilling zone Green playground stairs

Visual connections between different areas and entrances on the ground floor.

Division of the first level into four areas. Each of the areas needs its own entrance.

Adaptation of the configuration to create three different courtyards.

This existing building is connected by a parasite to the new building (one of the criteria of the Vallcarca assignment and possibilities of the system). The parasite is a slanted vertical staircase up to the conference room and the high ventilated offices.

There are in total 6 principal functional areas: the library area, the event area, the bar area, the market area, the offices area (situated on the second and third floor) and the workshop area. The workshops are divided over the whole building. It are spaces which can be rented for different uses. Next to indoor spaces, there is also creation of outdoor spaces.

The first courtyard is flat and is used for outdoor markets, food festivals, neighbourhood concerts and other events. The second one is bumpy and is the chilling zone. This zone is open to the public to picnic, rest, or have a nap under some trees. The third one is flat and is connected to the covered terrace from the bar. Parents can look after their children from inside the bar.

159

Structure of the generated building through the landscape of Vallcarca.

160

161

Wind analysis: SSW wind on the generated building In the left image we can observe the fluid dynamic wind analysis done with the SSW wind on the 3-dimensional model. Yellow-light blue means there is wind, dark blue means there is almost no wind. We can observe that the SSW wind is deflected by the building and that the courtyards are merely protected of the irritant SSW wind.

NNW wind on the generated building In the left image we can observe the fluid dynamic wind analysis done with the NNW wind on the 3-dimensional model. The yellow light blue means there is a lot of wind, the dark blue means there is almost no wind. We can observe that the NNW wind is coming into the courtyards .

162

School

Dog park

Metro

PUB 163

Relation W.E.F.T. - Topography

N Plan 1 164

Note that ‘l.v.’ stands for ‘low ventilated ‘ and that ‘h.v. stands for ‘high ventilated’

N Plan 2 165

15 m

N Plan 3 166

30 m

45m

Sections

A’

B’

Top Image: section AA’ trough the bridge, h.v. offices, lobby, play garden related to event bar, covered terrace, h.v. workshop, stairwell to exhibition room.

Bottom image: section BB’ through the first and second floor of the library and the l.v. workshops which are reading areas or also used for reading workshops.

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W.E.F.T. a generative system? Abstract Generative systems have more and more been studied over the last forty years, not only as systems for computing, but also as system methods recognised in the biological and design world. Generative systems, in particular shape grammar, have offered a unique computational theory for design and architecture. Shape grammars are being adapted to define ‘making grammars’ for computing different kind of things. In this paper, we analyse our own system W.E.F.T. and evaluate whether it is a generative system. Firstly, we study different approaches for specifying form generations, material properties and other specifications through shape grammars with their limitations and proposal properties. It was found that our own system W.E.F.T. is merely a generative system, that can be generated mostly by rules. After generating a population and evaluating it computationally, one option has to be chosen. This ultimate decision is not taken by computing, but by the mind of the architect and/or designer. Introduction Generative systems explain processes to generate any form of solutions. Generative systems are therefore linked to problem solving architecture.1-6 As we can observe in the latest trend of architecture, genetic algorithms, shape grammars and other evolutionary methods share the characteristic that they create a large number of designs. Because they generate different forms derived from the same set of rules, these different forms can be manipulated by changing parameters and values to select the fittest or most preferable results of design.6

1. Introduction into shape and shape grammars, G. Stiny, Environment and Planning B, 1980, Vol. 7, p.343-351 2. Regarding rules: from Rimini to Rio, Terry Knight. Magazine Coelho, 2014, Vol. 05 3. Making grammars: from computing with shapes to computing with things Terry Knight and George Stiny, Design Studies, 2015, Vol. 41 (Part A), p.8-28.

Firstly, before comparing our systems to other generative systems, we should clarify what means ‘generative design’.

4. Algorithmic beaty of Plants, Prezemyslaw Prusinkiewiez, Aristid Lindenmayer, Springer-Verlag, NY, 2004

Generative design is the method in which the drawings are generated by applying a set of algorithm rules. These rules allow us to explore new concepts and solutions. Etymologically, “gene-“ refers to the idea of a family or group that generates new members of the same group.

5. Structured dynamical systems, introduction to modelling with L-systems, Przemyslaw Prusinkiewicz, http://algorithmicbotany.org/papers/sigcourse.2003/1-9-L-fundamentals.pdf

Looking back into history, one of the first revolutionary discovered generative systems was the Turing Machine which can be defined as a formal system, the base for computation. Alan Turing defined a set of symbols and the way how to generate new strings by rules of formation – by manipulating the symbols on a strip of tape. A computer can be defined as a universal symbolic processor because it can process any symbol (which stands for something else) and it operates with these symbols by transformation rules.7 168

6. Generative systems, https://wiki. cc.gatech.edu/designcomp/images/e/e1/Minor-answer2.pdf 7. Lectures, Pau de Sola Morales, Elisava 2016 8. Lindenmayer systems, Fractal foundation,http://fractalfoundation.org/ OFC/OFC-2-4.html [Accessed 20 Juni 2016]

Another generative system, used daily by people, can be found in the theory of linguistics. It consists of a formal grammar (or simply a grammar) and of rules for structure with starting symbols and several rewriting rules. This theory was developed by Naom Chomsky: ‘All we do is generating systems of built-in grammar by transformation rules. We are generating sentences of language and then we are telling the words. 7,6 p.1,4 p.2 Shape grammar, a generative system Looking more into architecture, the theory of ‘shape grammar’ (generative system) appears to represent forms; or as Knight and Stiny define it: ‘Shape grammars are rule-based systems for describing and generating designs’ (Knight 1999, Stiny 2006).

Shape rules 1 and 2. Rule two is the erasing rule of the symbol.

G. Stiny defines ‘shape’ as follows: ‘Every shape is specified by a finite set of lines’.1 Starting from an initial shape (called an axiom), derived shapes are created by transformation rules. This system, as defined by Stiny, is also a formal system, just as the Turing Machine.1 Taken as an example, he describes in his theory two shape rules, as shown on the right. He starts from the initial shape. The generation of shapes by using these shape rules, called grammar, is shown in the next image. As we can observe, the shape rule applied on the initial shape is also applied on the next shape. On the third shape, the second shape rule is applied which erases the symbol • and no shape rule can be applied anymore. This generative system is similar to how a Turing Machine is working.

Initial shape.

Application of shape rule 1 and 2 to generate shapes.

Shape grammar, which is a description of form arrangement, is linked to design because it can represent how design has been evolving and how this generated grammar can produce many variations of design by applying the rules. In short, shape grammars generate rule-based design systems. 169

Each shape rule is “if-then” conditional or it is an instruction of the form A→B. The rule says, as shown in the previous images, that if there exists shape A in a design, it will be changed to shape B by applying a rule. These rules are applied repetitively as shown in the image, 2,p.15 So the concept of shape grammar is based on the concept of ‘rewriting’ which is the technique for defining complex objects by successively replacing parts of a simple initial object, using a set of rewriting rules or productions. So are also the L-systems defined by Aristrid Lindenmayer based on the concept of rewriting: they are conceived as mathematical theory for plant development. It is a mechanism to control asymmetric division.

L-system : splitting of branches by left and right side.

Taking a look at the starting image of the illustrated L-system, it is a straight line. Next, we apply a rule to the line 0, in this case, splitting it into two branches, one angling to the left and one to the right. The same rule is applied again (recursively) to each new branch. This process is being repeated so that self-similar patterns are being created. The essential difference between Chomsky grammars and L-systems lies in the method of applying productions. In Chomsky grammars, productions are applied sequentially, whereas in L-systems they are applied in parallel and simultaneously replace all letters in a given word. This difference reflects the biological motivation of L-systems, as cell divisions may occur at the same time in multicellular organisms. 4 The interpretation of L-system can be extended to three dimensions by representing the orientation by three perpendicular vectors with a specific length. By using these vectors in an equation, directional angles can be specified. 4 Lindenmayer makes a differentiation between OL-systems (= context-free Lindenmayer systems) and IL- systems (contextsensitive L-systems).4,p.3 So may the production application also depend on the predecessor’s context. For example, the growth of plants is affected by the flow of nutrients or hormones, which is in fact the mechanism of information exchange between neighbouring cells (interaction). Taking this kind of context in account helps to simulate the interaction between different plant parts.4,p.30, p.65

OL-systems also called DOL- systems are Deterministic Lindenmayer-systems with 0 interactions. 5, 4 170

A context–sensitive extension of tree L-systems (such as shown in the image) requires neighbour edges of the replaced edge to be tested for context matching. In a context-sensitive production, the predecessor p consists of three components: a path l forming in the left context an edge S (also called the strict predecessor) and an axial tree r constituting the right context as represented in the image. The asymmetry between the right ant the left context reflects, that there is only one way from the root of tree to a given edge. But there can be many ways from this edge to diverse nodes.4, p.31 In such context sensitive L-system of a tree, we observe and conclude that - if the production p (predecessor) matches a given occurrence of the edge S in a tree T, and if l is a path in this tree T terminating at the starting node of S, as well as r is a subtree of T originating at the ending node of S -, the production can then be applied by replacing S (the edge) with the axial tree specified as the production successor.4, p.31, 32 Left context < predecessor > right context: condition→ successor 5,p.23

IL-system: predecessor of a context-sensitive tree production (a) , matches edge S in a tree T (b).

As described by P. Prusinkiewiez during the derivation, the context modules may affect the applicability and outcome of a production application and only the predecessor will turn into the successor.5,p.23 In the context-free L-systems, there exists a parametric L-system, which includes a condition dependent on whether the production can be applied or not. Predecessor: condition → successor.5, p.11 Analysis grammar for design Looking into architectural existing grammars as the Palladian Villa grammar, developed by G. Stiny and W. Mitchell in 1978, it is an analysis grammar developed to understand and describe the design style of Palladio (an Italian architect active in the Republic of Venice, anno 1550). The grammar they developed can generate, depending on which rule is applied, the existing Palladian villa plans and even other new designs in the style of the existing ones. In contrast, shape grammars for design create only original possibilities.1,2

Some original Palladio villas.2

Palladian grammar: Examples of shape rules extracted from the different rooms created in Palladian villas. 171

Making grammars Shape grammars can be generalized to compute the making of material ‘things’ by ‘making grammars’.3 Two aspects are to be distinguished between making and computation. When ‘making’, ‘things’ are perceptible, real-world entities. To compute with them we should consider what they are materially and physically, as well as their properties and behaviour. This last aspect means that one has to find out with which formal algebra the properties can be represented computationally. Next to the ‘things’, the making activity itself, which is a ‘process’, should be considered. Two types are distinguished: the ‘doings’ (motor / body actions) and the ‘sensings‘ (visual, feeling…). How making these processes, should be represented by a rule A→B. These sensings and doings can occur simultaneously or independently and should also be translated into computation. Next to these two main aspects, as mentioned by Knight & Stiny 2015, there are other important aspects, such as context, environment, resources and people. 3 An example is given in the images, illustrating the sensing and doing rules of knotting by Ingold 2007.3 The grammar generates overhand knots along a string. There are three dimensional strings, which are represented in algebra as shown in the images on the right and there is the process which consist of knotting (looping, pulling…) = ‘ the doing’, and the process of touching with the hands = ‘the feeling’. There are two types of rules: rules of knotting and rules of touching/ grasping, as shown below.

Knotting a string with the grammar of knotting and sensing.

172

Making grammar: Knotting with string. Sensing rules

Doing rules

A and B represent the changing of the grasp location along the string in which the red brackets indicate the locations of left and right hand grasps (as in all the rules); a bracket open to the left represents a left-handed grasp and one to the right, a right-handed grasp. C represents the changing of the hand from under the string to over the string. The knotting rules represent the pulling and looping in different ways. The sensing rules can be applied at any time and the knot can be made in different orientations and directions. There are natural stopping points integrated in the knotting rules. The goal for developing algebra for making and sensing is to capture the physical reality of independent strings, and their versions and combinations.

The generation of W.E.F.T.. We don’t see our system as an intellectual activity, but it is a design that can be scripted in advance. Depending on where it will stand in the world, it will take another configuration. Our system is responsive to the wind and the view. So, in order to research if our system can be a generative system, or at least if parts are generative, we have to describe every step in our process that created the configuration and the form. Every architectural system has a moment where we have to take decisions which cannot be based on rules, even although some of these decisions can be described by and transformed into rules. The challenge , however, is how to translate each rule into symbols and – as to consolidate these into a program and into a set of solutions – to find out whether all steps can be translated into symbols. Symbols (as numbers and words) can restrict the way in which a rule can be applied, such as in the example by Stiny with the erasing rule. Our system can be divided into three main parts: The first part is placing the program (for placement of the “rooms”) on the building site based on a wind/view analysis. By researching the wind and view on the plot(s), different areas are being created, allowing placing the program. The second part is analysing the system on responsiveness to the wind: for instance, our system should deflect or block adverse winds, such as a hot strong wind, and let enter pleasant winds, such as a fresh summer wind, into the courtyards or guide these through the building. The third part is the analysis of the system capacities: our system is a woven membrane between curves which are constructed by circles and bi-arcs, who are defined by the nodes (centres of the circles which are the activity spaces) and the vertices (length between two circles). In this part we should analyse whether the system can be built, and thus whether it complies with the system rules. Translation into symbols As mentioned above, we have to describe every step by a rule. The rules of our system should be translated into symbols such as numbers, words, letters …. Instead of starting with placing the program with the rooms, we start to place the nodes according to their values, which are the centres of the program areas. Every node will have a start vocabulary. Throughout following the rules, this start vocabulary will be used continuously. 173

Start vocabulary: Each node / point is defined in the beginning as Pn (R,NNWV,SSWV, La,b,c,…), with: Pn : the amount of nodes, or how many rooms we need. R : the radius of circle with as centre the node/point. R has a specific domain. R ϵ [1.95m;10 m] : the requested area, translated into a radius.

NNWV: NNWV ϵ N ˄ ϵ [0;10] This parameter is the sum of the values of the NNW wind (its strength being mapped between [ 0 ; 5] ) and the views (translated into distances and also mapped between [0;5] and V ϵ N) NNW (ϵ [0,5]) + V (ϵ [0,5]) = NNWV (ϵ [0,10] ˄ ϵ N) SSWV: SSWV ϵ Z- ˄ ϵ [-10;0] This parameter is the subtraction of the views (distances mapped between [0;5] and V ϵ N) from the values of the SSW wind (its strength being mapped between [ -5;0] ϵ Z- ) SSW (ϵ [ -5;0] ˄ ϵ Z-) – V (ϵ[0,5]) = SSWV (ϵ Z-˄ ϵ [-10;0]) The wind values will be different depending on the country/city where we have to build our system. In some places, we might have enough with analysing one value, in other places, we may need to calculate and evaluate more values. For practical case-analysis in this project, we choose to build in Barcelona where we have two major winds, the NNW and the SSW. We used the following rules, as to decide which value is the most important to apply. When | SSWV| < |NNWV| the NNWV will be used. When | SSWV| = |NNWV| both values will be read. When | SSWV| > |NNWV| the SSWV will be used. La,b,c,… represents the parameters defining with which nodes connections have to be made (a,b,c,… ϵN) . For example P1(15,NNWV,SSWV, L2,5) should be connected with node P2 and P5. It is not possible to create more than four links with one node; this is a restriction of our system coming from the system capacities.

174

Placing rules: 1) The next steps define the placing rules of the vocabulary to generate basic solutions of our system W.E.F.T. Place the node Pn(R,NWV,SWV, La,b,c,…), with the biggest radius (R). The node Pn his NWV and SWV numbers are analysed. When | SSWV| < |NNWV| the NNWV will be used. When | SSWV| = |NNWV| both values will be read. When | SSWV| > |NNWV| the SSWV will be used. The node will be placed in the generated centroids of the areas 2) Construct the related circular space of the nodes, with the allocated radius. 3) Detect the intersections of the circular spaces with the borders, with themselves or with already established links. + Delete the circles that have intersections.

NNVW NNWV Place the nodes op the Place the nodes on the open plots with specific NNVW lots with theaspecific NNWV

R P1

P1 Seeing Seeing

Eliminating Eliminating

Node center Node / center of the space

Parcel border Parcel Border

The value of the NNWV The value of the NNWV

Room

Diagrams illustrating rules 1 to 4 .

175

4) Delete the links which are outside the distance domain. The distance domain is: [(R_n+R_(n+1) )*1.2;(R_n+R_(n+1) )*2.1]. This domain is derived from the system capacities. 5) Place the next node which has a link with the previous one. => Redo steps 1 to 5 6) Place the nodes which have links with links of rule 6. => Redo steps 1 to 6 7) If there are no links anymore, go further with the leftover nodes => Redo steps 1 to 7

Pa Pa

SSWV SSWV

Pa Ra

Pa P1 Eliminating Eliminating

P1 Pa

InInthese example a population of z these example a population of 2 elements is left go on on. elements is left totogo P1 Seeing Seeing

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P1 Eliminating Eliminating

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Analysis of the wind responsiveness: The wind grammar is based on powering the wind by guiding, deflecting, blocking and enclosing it. Therefore, we take our populations generated in the previous part and add the main wind vectors. In the environment of our case (Valcarca, Barcelona), we had two winds that we can divide in a positive and a negative vector. This is done because the NNW wind is a fresh breeze coming from the mountains (favourable -> positive vector). The SSW wind is a warm, dry wind (discomfort ->negative vector). The guiding and enclosing are grammars needed at the positive vectors (NNW), the deflecting and blocking are needed at the negative vectors (SSW). (See image)

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The left image shows how we evaluate the populations with the vectors. If the overall configuration is not following the wind grammar, the population is deleted.

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8) If the bad wind is entering the courtyard, than the option is deleted.

9) If the bad wind is guided through the building, than the option is deleted. 10) If the good wind doesn’t enter the courtyard by entering or deflecting, than the option is deleted. Eliminating

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The wind-grammar will eliminate a lot of populations of the first stage, although these steps alone are unlikely to result in the ultimate solution. We still have to evaluate the system rules first, to see if all these possibilities can be built. Eliminating

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Making the system At this stage, we are left with a second population which still needs to be translated into a more architectural language. The links have to be translated into volumes. Before doing this we should analyse whether we can construct our system. 11)If the angle between two vertices is less than 40°, the option of the population is deleted. With the second population, we start creating the bi-arcs between the circles determined by the links. The creation of the bi-arcs is submitted to certain parameters. Distance between each other, was one of these parameters. Other parameters we have to take into account are the opening(s) in the circles and the opening(s) in the middle of the bi-arc. 1)Make the openings in the circles with an angle between [40°; 90°]. If there is more than one opening, start with the opening where the sum of the radiuses is the highest. This is because the angles could influence each other and the bigger the radius, the bigger the angle has to be.

2) Make the opening(s) between the two arcs between [1m; 5m]. The opening is determined by the amount of people who use this link and the size of the radiuses.

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Architectural decisions After these three stages, there is still the possibility, as we had in our generated population for Valcarca, (p.156), to have more than one option in the population. At this stage, we evaluated the population by architectural qualities. These include: 1) An analysis between public transport (metro) and the main entrance. This means that there should be a visual link between the metro and the entrance through a street or another open space such as a courtyard. So, if there is no visual connection between the metro or other public transport and the main entrance, these options were deleted. 2) An analysis of architectural quality of the public spaces (open or covered) which are created by our configurations. We deleted the configurations where half open courtyards have no view. In this Barcelona case, these two ‘architectural’ rules were enough to obtain the final configuration. In other countries/regions, it can be that there are more and/or different rules to be applied. The architectural decisions depend on the program, the location of the W.E.F.T. system, the usage by consumer and also the wishes of the client.

The option of placing and building our system W.E.F.T., as shown on the left, is our chosen final generated configuration from the generated populations after adding and integrating these two last architectural decisions. The red arrows are representing the SSW wind, one of the two main winds of Barcelona, which is a bad hot wind in summer and which is deflected. The green arrows are representing the second main wind, the NNW wind. This is a fresh breeze in summer and should enter our courtyards. Each created courtyard has sufficient view distance.

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Event plaza chilling zone Green playground stairs

This final configuration can be submitted to small architectural changes. These changes will never affect the overall configuration. What could happen, are slight movements, enlargements or minimisations in order to create better courtyards, circulation or interiors

Growth in the z-axis The nodes of the second and third level of our system W.E.F.T. should be placed in their related view and wind areas ( see p.157). But a question we still have to answer is: when does the next level start and how? We can consider to options : Option 1: The nodes can have a 5th related element F to a node Pn(R,NWV,SWV, La,b,c,…, F) F indicates in which floor it has to be located. So the division of the program into levels occurs before generating the system. Option 2: When more than 50% of the area is occupied, the system starts occupying the second level. 181

Conclusion: In postmodern architecture, ‘some architects’ proclaim the idea that the computer generates the architecture to achieve an objective design. In their mind the computer generates a better result because it is able to test more solutions and so may come to a better design. The architect together with other collaborators, often in a multidisciplinary team, will fabricate the program, by establishing rules, and which results in a set of solutions. Within the set of solutions obtained by a program, a further search for the best solution is needed. So, in line with the criticism by other postmodern architects that a good design cannot be achieved by a computer only, the intervention of the mind of the architect is needed to steer the process and to obtain an adequate result. This is what we did with W.E.F.T.. Overall, this exercise was found to be successful, not only in showing that our system is generative, but also in discovering new areas where we have to investigate and spend more time and efforts, as to make the system even more generative. We showed that our own system W.E.F.T. is merely a generative system that can be generated mostly by rules with the exception of one step: the transition between the point placing and the translation of the system into architecture. Our research also points to the reality that in the end, the ultimate decisions are not just made by rules alone, but also by the mind of an architect. These decisions are to enhance the architectural quality and eventually user-friendliness or clientoriented demands of the project. Examples include connections of entrances with other public spaces or transport. Yet, it is acknowledged that it is sometimes possible to also translate these decisions into rules, as we did with the entrance to the metro in our Barcelona case. The generation of a building computationally can lead us to a good option for responding to the environment. The computation will generate possibilities which we couldn’t imagine. But besides ‘environmental rules’, the generated population should be evaluated by rules based on the point of view of architecture, design, client demands and user attitudes, and therefore, its surroundings conditions. After choosing the best option by rules and by mind, some adaptations should be done to improve architectural spaces and connections, in such way that there is a fluent circulation, communication and connection between open and closed spaces. To compare our system to the research of Darwin, our system can be seen as a “bird”. This bird will have different physical characteristics depending on the environment (country) in order to survive. But in the end, all the slightly different ‘birds’ still come from the same species… and as in our case, will be swarming out, being generated from the same original W.E.F.T. system.

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Manufacturing diversity seminar Cladding and structural research Prototype 1/250 Prototype 1/50

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Manufactering diversity seminar In this part, there are first different materials tested for the construction such as joints, load-bearing elements and cladding. The materials were also evaluated ecologically to search a non-conventional ecological material. This led to a proposal of natural elements, which contribute to the task of an ecological building. This part on materials and options for manufacturing/building the system needs to be further investigated in the future. At last, we also explain how we construct a prototype of W.E.F.T. on scale 1/50 and on scale 1/250.

Material testing: joints 1; Natural materials Sisal 6mm (extracted from the leaves of Agave Sisalana), is strong (breaking load 240 kg) and is moisture-resistant. Some disadvantages are: it is susceptible to rot, and lives only 1.5 year.

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Other option: polypropylene rope: doesn’t rot, is stronger, lives 15 year, is cheaper, but is artificial/synthetic. 2; Resin based ‘epoxy’ Epoxy is a strong and durable resin, it has an unlimited life, is 100% waterproof and is solventless, but nonrecyclable a ) Cotton (natural) b) Glassfiber (toxic) As general rope, cotton 8mm was used, such as in the small prototypes. 186

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Material testing: cladding Glass fiber + epoxy: Translucent, strong, windproof, difficult to apply, bigger environmental impact than natural fibers in composites. Sisal: natural fiber + epoxy: Easy to apply by the weaving technique, wind and water-permeable, the resin let the sisal lasting longer.

Sisal + curtain + epoxy In the beginning one could see through the curtain, but after applying epoxy it was only translucent. The drops are breaking the light and the view is blocked. Sisal: Woven through the structure, is easy to apply, but rots after 1.5 year.

Sisal winded in 4 directions: The rope is winded around the load-bearing structure in 4 directions. The structure can be seen as a cushion: between the two layers there is air, which can act as insulation.

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This air can only be retained and act as insulation when there is something applied on the rope such as resin. air 187

Recycled paper + epoxy Using recycled paper and epoxy, you get a stong skin, which is waterproof due to the epoxy. Holes from the same size can be kept open to standarize the window size. The paper is first applied with the ‘papier maché’ technique, using wallpaper paste. Woven veneer Woven through the load-bearing structure and also woven by itself. Easy to apply. Wind and rain can pass a little through. (Other option; branches)

Transparent curtain + epoxy The epoxy is filling the holes. Normally epoxy is transparent, but - in the combination with the curtain selected in this test - it doesn’t let the view pass anymore. So this composite can’t be used to let the view pass through. Textile Woven textiles can be woven through the woven structure: cotton, glass fibre... 188

Conventional solutions Metal + glass Looking to more standard materials, our structure can be made in steel and glass (such as produced by Cricursa). First we should consider that these materials are not produced in a real ecological fashion. Yet, these materials are durable. These technique can thus be considered.

Bamboo Looking to more ecologically produced materials, bamboo could be a solution. It has the capacity and compression strength between wood and metal. To put the bamboo in the foundations, a screw-wall principle can be used: this can be achieved by cutting the down part of the bamboo in slices and inserting a flatted cone as shown in the right image.

Emporia shopping mall, Malmö 2012, Cricursa Inspiring Glass Solutions, Retrieved from: www. cricursa.com [Accessed 12 June 2016]

Bamboo

50 mm cutted

Rubber 50 mm - 60 mm

Inner frames with bamboo used for windows ,Eco Bamboo Home, http://www.bamboosdesign.com [Accessed 12 June 2016]

Note that the hyperbolic curve will more tend to a hyperbolic paraboloid. Each crossing between two bamboo elements should be connected by a joint. The structure will not be woven, but will be interlaced by the joints. Depending on the cladding, the joint can be rope or should be a more sophisticate joint, for example, to enable windows (see image).

Subsequently, bamboo reinforced with rubber is inserted in a cylindrical hole in the foundation by pushing the Bamboo cutted down part together. Note that radius + rubber of the cylindrical hole is equal at the radius of the bamboo. The rubber will expand in the foundation and the bamboo will be fixed just like a screw in the wall.

Foundations with hole 50 mm

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Breakthrough solutions How would it be, when this building structure of three floors could just exist by a composite of rope (or another fibre) and a resin? That robots could weave this kind of structure, while the hyperbolic created shape contributes sufficiently to the strength to hold the three floors? Would it not be even more fantastic that the cladding would be woven through the structure and is made impermeable just by applying resin? That the visibility through the skin is made by the holes between the weaving, which could even be standardized in a cladding system using paper (visualized below).

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The breakthrough structural solution of a whole woven system will need some more investigation in the future.

Possible solutions for cladding: (Top) Cladding in direction of the strings is easier to apply when it are bendable flat pieces. (Bottom) Use of standardized holes as windows.

Prototype 1/250 The prototype on scale 1/250 is made to understand better the spatial qualities, generated by the system, such as the configuration of system itself, as well as the generated courtyards. Green areas and vegetation are indicated on the CNC-model to understand better the different kind of zones.

3D printed piece.

The system was 3D printed as a closed building with the structure visible.

Final model scale 1/250.

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Prototype 1/50 This prototype is only one part of our whole configuration in Vallcarca, it is the conjunction of the market together with the high ventilated offices and the parasite. It shows some characteristics of our system such as the compression beams of the roofs, the capability to parasite and to highly ventilate, as well we to create outer roofs and squares. The structural beams from this prototype are made in 3D printed pieces which are assembled puzzle-like. Some parts have a bulging piece, with a hole, in which structural metal bars have to be fixed. This structure of metal bars needs to be made to maintain the beams in place during weaving and thus to enable to weave, it could be compared with the scaffoldings. After everything is woven with cotton wire, the epoxy resin is applied. When the prototype is dry, the metal bars are taken out and the bulges are cut off the beams. The prototype is placed in the site model which is made out foam and cartboard and shows the relation to the ground floor and neighbourhood.

Image: indication of the area chosen for the prototype.

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Final prototype: ‘setup.’

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Final prototype & details

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Final prototype and setup.

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Design tools Rhinoceros Grasshopper Autodesk VectorWorks V-Ray Arduino Photoshop Illustrator InDesign RhinoCAM 3D printing Laser-cut CNC Milling

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W.E.F.T. A project in research This book presents a year of investigation of an architectural generative system that can grow horizontally and vertically in responsiveness to wind and view, owning the structural and porosity characteristics of weaving. The system is not only responsive to the wind but it can power the wind by guiding, deflecting, channelling and blocking the wind. This is of great importance to introduce a green ventilation system and this even means that in zones where there is a lot of wind, even green energy could be produced. Form-finding, responsiveness, parameterization, sitesystem contextualisation and materialization are explained in this book always related to theory and research.

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