Continuous | Complexities
University College London Bartlett School of Architecture 2015-2016
Continuous Complexities An Integrated system of natural fibrous structures
Submitted in partial fulfillment of requirements for the MArch Architectural Design B-pro
Noura Mhied | Research Cluster 6 Supervised by | Daniel Widrig - Soomeen Hahm - Igor Pantic - Stefan Bassing
Report Tutor | Lisa Cumming Submitted on: 22nd of July 2016
Zoom in on felt clipping mask
Noura Mhied | Wonderlab - Research Cluster 6, 2015-2016 Supervised by | Daniel Widrig - Soomeen Hahm - Igor Pantic - Stefan Bassing
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CONTENTS Abstract Introduction Chapter 1 | History and development of fabric
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1.1 Woven and Non-woven textiles 1.2 History of craft techniques 1.3 Fiber continuity Chapter 2 | Building with fabric
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2.1 Historical fabric structures 2.1.1 Early tent structures
2.2 Modern fabric structures 2.2.1 German Pavilion, Montreal
2.2.2 Fabric Customization
Chapter 3 | Continuous structures
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3.1 Material continuity 3.1.1 Material control
3.1.2 Materiality in fabrication
3.2 Structural continuity Chapter 4 | FleXtiles
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4.1 Studio research 4.2 Initial studies 4.3 Fabrication development Chapter 5 | Future recommendations
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Conclusion Bibliography
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Abstract The emergence of modern ‘free-form’ designs has challenged practitioners to seek for new fabrication techniques that can easily create such structures with less time, effort and material. As such, this research investigates the age-old craft of felt-making and the potential of non-woven fabrics in the production of architectural structures at various scales. The project will focus on introducing the potential of fibrous wool material as a new building block, for creating organic structures that smoothly transition from soft to hard textures, to create new spatial sensations and experiences within the field of architecture. By going beyond the traditional uses of felt wool and reconsidering its many natural-given properties, architecture can create spaces that combine both the natural and synthetic, a concept that has yet to be fully exploited in the man-made world of architectural design.
This research will firstly discuss fabric through history up until its most recent developments and uses in our present time. It will also explore the hidden potentials of using such a versatile, natural material in the development of a new environmentally friendly craft that is specific to the material and requires no chemical enhancements to make selfstanding and light weight structures for architectural use.
It will specifically propose felt wool as a new reformed material for the construction of continuous structures. These are composed of various components that are seamlessly connected without stitching, adhesives or any kind of joints. It will also highlight the structural abilities of felt wool given its unique materiality while using high technology, robotic fabrication techniques to create self-standing forms. By transforming a naturally soft material into new found complexities and optimized structures, the use of felt fibers can revolutionize the way architectural forms are built today.
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Introduction Wool fibers have been used for many years throughout history to make different kinds of textiles for clothes and shelter. Nowadays they are being used for a wider range of products from artistic sculptures to thick acoustic panels in building construction. However, this versatile material can be processed in various ways to simply adjust its physical appearance and characteristics according to different functional requirements, which makes it quite intriguing to develop complex forms in architecture.
Felt wool is also very responsive and can be smoothly controlled to be shaped into various forms unlike most traditional materials. However, its structural abilities have yet to be tested to the limits, specifically in larger scales. So far, felt fibers have been compressed into flat sheets that cover inner structures of wood or metal. This paper will address this issue and propose how such a flexible, adaptable material can create self-standing and light weight structures by relying on the natural ability of felt to easily transition between hard and soft textures.
The unique methods in which fibers are compressed together to transform themselves into a solid mass is also another attribute for the perceived continuity in a felt wool structure. When fibers are merged together, they form an irreversible and resilient bond so no adhesives or stitching is required to join different parts together. Such a naturally given intelligence can create endless possibilities in creating stronger and unbreakable structures.
With the rise of technology in the architectural industry, the need to revolutionize materiality in structure is evident. Therefore, this research will firstly discuss the natural abilities of felt wool and investigate its hidden potential in the production of a much more tactile architecture with unique spatial and visual experiences. It will also investigate how the materiality of felt can inform its structural ability in redefining fabric architecture as a whole. As well as, suggest for the hybridization of a low technology craft with modern fabrication technologies to reduce wasted material in construction. This research will then address the concept of an integrated, continuous architectural system and its main advantages over traditional segregated building designs in optimizing structural performance and overcoming typical challenges in fabrication.
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Chapter 1 | History and development of fabric
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1.1 Woven and Non-woven textiles Textiles are among the oldest man-made materials in history. They date back to pre-historic times and were mainly used for shelter and apparel. The structure of textiles and how they are manufactured is what differentiates them apart in characteristics such as appearance, texture, flexibility and porosity. Textiles mainly form into two groups; woven and nonwoven fabrics. Woven fabrics are mainly made of yarn or thread and weaved together in certain patterns to create a sheet of fabric. Traditionally, they were spun together using a spinning wheel however, nowadays the weaving process is more mechanized. The general stability and ability of a piece of fabric to conform to any shape mainly depends on the weave style. While, nonwoven fabrics differ greatly in their inner structure. These textiles require no weaving or knitting to form into a fabric and are made from the batting of fibers together to form a sheet of fabric. The fibers are entangled together in no specific pattern and strength of the fabric is achieved by the densification of more interlocked fibers. This type of fabric was most commonly used throughout history for its high absorption of moisture and its excellent insulation. Also, since this process of fabric-making only required the addition of heat, moisture and pressure by hand, it was quite popular among various civilizations of mankind. This method was mainly used to make felt out of sheep wool fur, the oldest kind of fabric known to mankind (A.W. Koester,1993). Figure 1 below illustrates the difference in internal structures between weaved, knitted and nonwoven fabrics .
Internal structure of different types of fabrics (Polona Dobnik Dubrovski and Miran Brezocnik (2012).
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1.2 Development of felting techniques The craft of felt-making dates back to pre-historic times. Generally, wool fur from animals was gathered and compressed together to form the fabric using only hot water. The unique natural structure of each fiber is what gives it the ability to be felted into fabric. Each wool fiber is composed of exterior cuticles that interlock with others when agitated in moisture. The image below, shows an exploded view of the structure of a single fiber (Biotechlearn.org.nz, 2010).
Exploded view of the various structural units of the wool fiber (Source: Geoffanderson.com, 2011)
In more recent times, specifically preceding the industrial revolution, mechanical needle felting was replaced for the production of felt fabric in less time and with the least amount of manual labor. On the other hand, this procedure substitutes water and heat with barded needles that when pushed into the fibers, interlock them together into a single sheet of material (Kamath, 2004).
In this method, the texture and thickness of the felt sheet depends on the amount of fibers as well as the number of times the needle pierces through the network of fibers. The felt sheet densifies and increases in strength the more material is pushed through. The shape and size of each needle also affects the compactness of the fibers together. The following image illustrates how a felting needle collects the fibers together (Kamath,2004).
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A closer look of a felting needle ( Author’s own, 2016) In order to understand the properties and different ways of processing felt fibers to produce felt sheets, both techniques were initially experimented with and the different samples were compared against each other. It was evident that the difference between the two techniques produced different thicknesses and different textures of flat sheets. The end result all depended on the initial fiber arrangement and the way they were entangled together to form one unified felt sheet. The below images demonstrate the different end result of wet and needle felted samples.
Nowadays, both methods are still being practiced by designers in the textile industry yet none have truly explored its true potential. And so this research will investigate how to transform such a low technology craft into a high technology fabrication technique to produce a material with higher structural abilities.
Sample 01
Sample 02
[4] Fiber layers
[8] Fiber layers
Sample 03 [12] Fiber layers
Different samples of needle & wet felting ( Author’s own, 2016) | 12
1.3 Fiber Continuity As previously mentioned, nonwoven textiles can easily be adjusted by differentiating the structure of the fibers on a micro scale. This control on the behavioural aspect of the different fiber arrangements easily allows for the adaptation to various design criteria. The resulting homogeneity of fibers introduces a new level of material organization potentially expanding the scope of materiality in design. By utilizing this unique feature of natural fibers, materiality can be simply reflected on to varying scales within the different design stages and overall fabrication.
The continuity of fibers is transferred from one element to another on both the micro and scales of a prototype. Thus even in larger assemblies such a homogenous material can expand the way different design elements form and connect with one another. In the Architecture of Continuity, Lars Spuybroek defines this type of continuity purely as a relational organization of elements within a whole system. Despite the fact that architecture is naturally viewed as an assembly of segregated parts, Spuybroek promotes for a deeper configuration between these elements. To further elaborate this ideology, in his book Spuybroek compares the architecture of conventional buildings as isolated predefined parts of columns, slabs and so forth to historical Gothic structures where all the resulting elements are a consequence of their initial relation to a single element, the ribs. Spuybroek describes the rib as a relative element that varies in different states by bundling into columns and fanning out into vaults creating uninterrupted ceiling structures of immense spans. This constant connection between the different parts of the building is what creates a continuous gradient of transitions, as opposed to traditional buildings where these elements are treated separately. For example, the church of Saint-Nicholas-des-Champs demonstrates how the ribs disguise the connections between the columns and the vaults creating a seamless and continuous gradient of materiality and design (Spuybroek, 2009).
Spuybroek’s view of the rib as a self-organizing element that changes into various forms, is similar to the materiality of felt fibers. In the studio research, the fiber is seen as a continuous entity that runs through each separate fabric component. Similar to the repetitive rib element, the same component is used but in varying weaving and interlocking positions and are fused together at the edges by simply needle felting them in place, creates a single unified piece of three dimensional textiles. The fiber ‘ribs’ not only connect the different components in a continuous order but also give the overall shape and form to the fabric. In this way, a homogenous relationship is maintained between the individual parts, comparable to the continuity achieved in gothic architecture.
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Chapter 2 | Building with fabric
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2.1 History of textile structures Tent structures are considered to be one the earliest constructions using fabric in the history of mankind. Its most basic application was in the form of simple tents made out of animal skin draped on wood from trees. Such structures were readily made due to the abundance of natural materials such as animal skin and were easily assembled or adjusted according to the changing environment. They are also quick to assemble for temporary uses setting them apart from other architectural construction techniques at that time. The two main examples of historical fabric structures were the ‘Black tent’ and the ‘Yurt’.
2.1.1 Early applications The black tent was originated by the nomads and is considered to be the first type of tent structure in history. The fabric used was mainly of animal fur. It was easily made from animal fur and was used for its durability, light weightiness, and resistance to water. The fabric was mainly used to provide privacy and protect from harsh weathers and so it was very suitable for their nomadic life style. The structure was simply made by fastening the fabric on top of branches from fallen down trees. The purpose of the fabric was used as the roof of the tent and was the most important feature of the whole wooden frame. Such structures are still used till today in most rural areas of the world for its easy set-up and portability (Kuusito, 2012)
Yurt (Kuusito, 2012) | 16
The Yurt on the other hand is an advanced form of the traditional tent. Its structural frame is enhanced and the fabric covering is made of felted animal fur. It originated mainly in the central regions of Asia and Turkey. This structure differentiated itself from the previously mentioned type of tent for its more complex wooden frame, added functional features, and use of wet felted animal fur for the covering instead of animal skin or fur. The self-bracing structure formed a cylindrical shape with a dome as its roofing system. Its most distinct feature was its ability to be demounted temporarily to be moved as a whole piece by horses to different locations. The felt was also used in different variations according to the different climate changes. So even back then the versatility of this material was exhibited and was processed differently to either produce light covering for the summer or heavier covering for the harsh winter weather. The yurt is still in use nowadays as well but with more permanent structures. It was also used as an integral material in the structure of the yurt. The felt’s flexibility to form into the shape of the inner structure and carry loads of the roofing structure made it a distinguished piece of architecture for its time (Kuusito, 2012).
This research investigates such conventional tent structures that are self-supporting, and able to seamlessly shape into walls, ceilings and roofing systems. However, in these basic structures, the internal scaffolding is created separately from the fabric and is shaped into a three dimensional structure completely disregarding the strength and shapability of fabric. The wooden frame is used to simply drape the fabric covering on top creating a weak relationship between the two layers. Such an approach was further developed within the research to create a stronger relationship between the fabric and its inner structure. By embedding the inner structure into the fibers of fabric a single, more reinforced textile material was shaped into three dimensional shapes and maintaining the homogeneous quality of the tent structures.
Transformation from a flat sheet into a three dimensional form (Author’s own, 2016) | 17
2.2 Modern applications of textile structures With modern advancements in technology and fabrication, textile structures have been developed to enhance their natural properties and perform beyond their preconceived abilities. The light-weightiness, strength and durability of fabric is the reason this type of architecture was favorable throughout history until this day. However, being more developed, these structures still maintain the same functionalities and structural aspects that were inspired by history. The most witnessed advancements in textile structures were preceding the Second World War along with the development of construction systems. Most of these structures used fabric to achieve larger light weight buildings in the least amount of time (Kuusito, 2012). And so it was evident from this progression that fabric could potentially be used as a structural element in designing architectural scale buildings. Frei Otto was one of the leading innovators with experimenting with light-weight tensile structures. His work essentially inspired this research to explore how fabric can expand into a structural network of surfaces.
2.2.1 German Pavilion, Montreal This building specifically brought about a new definition to tensile structures in architecture. The organic cable-net structure was Frei Otto’s first large scale project in which a polyester fabric was suspended from the structure as a secondary skin. The whole roofing system was of cotton fabric, replicating traditional tent like structures that were also prefabricated and easily assembled. His research and work into structural pre-stressed fabrics continued to lead the world into developing tensile structures in architecture (Kuusito, 2012).
Organic, cable-net structure by Frei Otto (Kuusito, 2012)
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In the Architecture of Continuity, Lars Spuybroek proposes a different approach to the use of the fabric material in architectural structures by rethinking the fibers on a more intimate scale. Rather than adding the soft fibers to a rigid framework, Spuybroek suggests for the transformation of the soft fiber into a rigid structure. By reconsidering the materiality of fabric material itself and merging both layers of fabric and structure into one, the fibers move towards each other and interlock becoming the rigid structure. Establishing a deeper relationship between materiality and structure will create forms that smoothly transition from soft to hard (Spuybroek, 2009).
Viewing the fabric as a continuous fibrous entity rather than a fragile flat sheet, this concept is what this research is developing. So rather than creating forms out of ready-made sheets, the project uses the fibrous raw material of fabric to be able to control the material behavior on a local scale and then reflect this on the overall structure. This approach introduced a new level of structural ability to textiles by altering its unique materiality into the structure itself and thus creating self-supporting felt fabric prototypes such as the one below.
2.2.1 Fabric customization Along with advancements in the construction of tensile structures came the evolution of enhanced fabric and fabric-like materials. New fibers were designed to enhance flexibility and structural performance to exceed the natural behavior of textiles. In ‘Tension Fabrics: Waves of the Future’, Mark Weaver explains how the internal structure of fabric is what affects the overall performance of textile used in construction. Textiles mainly are differentiated by the type of fiber used to create them and how they are weaved together. And so, different types of textiles perform differently in various conditions. By reinforcing the fabric, more structurally stable forms were designed with less material compared to other construction systems (Weaver, 2005)
This approach was most commonly applied in pneumatic structures. With the need to create buildings on larger spans but without the need for expensive inner structure, inflatable buildings were introduced in architecture. New textiles were needed that could withstand the stress and strain of being supported by air as well as flexible enough to be inflated into large structures. Below is an example of a pneumatic building by the Fuji Company for the 1970 world expo (Kuusito, 2012).
The Fuji Group Pavilion pneumatic is the world’s largest pneumatic structure of its kind made of a composite fabric to enhance its load bearing ability as well as its elasticity. It was made of a double layer polymer fabric, attached together by an adhesive and coated with a specialized PVC material to guarantee air-tightness. The structural membrane elements were air-filled and connected together by a cable-net system (Kuusito, 2012). The hybrid structure transformed membrane tensile structures and introduced new possibilities in fabric architecture. | 19
Taking inspiration from both construction techniques of tensile and pneumatic structures, this project investigates how to create customized fabric while crafting a stronger connection to a self-supporting structure that will enable the fabric to transform into complex three dimensional forms. By combing both approaches, this research presents the flexibility of fabric material as more than just convenient roofing systems but to develop it into more integrated structures and utilizing the fibrous strength of fabric in creating self-standing continuous organic forms.
Fuji Group Pavilion (Kuusito, 2012)
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Chapter 3 | Continuous structures
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Most natural systems are categorized for their unique material and structural organization which features high efficiency and optimization. The way that such integrated systems respond to external forces are extremely intricate and provide novel models for innovative structures in architecture. Specifically, their ability to differentiate between the different material performances complex according to complex gradients of material and structural distribution. Plant systems, in particular, demonstrate how different levels material organization can achieve different structural abilities. Bamboo stems are one of the many examples in nature where the distribution and density of material are self-organized according to environmental forces such as gravity and the wind. The fibers inside the stem are mainly arranged depending on their height so that the upper portions consist of tighter bundles to withstand gravitational and wind loads. The differentiation in fiber organization and bundling effect the overall elasticity and stiffness of the bamboo stem material. This offers an interesting model for the study of differentiating performances of a single material and its role within a whole system (Weinstock,2006).
Another interesting aspect of the biological system of a bamboo is its connection with other components. The fibrous material is continuous and transitions by decreasing stiffness when transforming into the leaf and so technically there are no divisions between the steam and the leaf but rather a shift in the physical structure of the fibers to create the different parts. Thus creating a continuous system of alternating levels of material performance based on its differentiating inner formations (Weinstock,2006). The below images represent the differentiating densities and distribution of fibers inside the stem of a bamboo.
Bamboo stem and cross section ( Boo, 2013)
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Natural systems embed materiality in structure and that is what this research aims to explore in textile architecture. Such integrated organizations offer many advantages over conventional architectural design processes and suggest for the rethinking of structural joints altogether.
So far most traditional fabric structures use compressed fibers into making flat two-dimensional sheets that are then formed according to a predefined inner structure. The materiality of fabric and its inner structure are completely segregated layers and eventually do not portray the true versatility of textiles and their ability to be customized into complex architectural formations.
Nowadays, most designs are split into various elements that are connected either with mortar or specifically designed joints and extra consideration is taken into these connections to make them strong. Despite these efforts, these connection points are still considered to be the weak points of any structure. However, in this project by experimenting with fibrous materials it was discovered that these joints become seamlessly merged into the design as a whole. The connections created between the many components is very strong and resilient since the wool fibers of each are entangled together and the bond created between them is then irreversible and unbreakable.
A sense of continuity is also naturally achieved since these joint-less connections don’t require any adhesives nor stitching and are just attained by the simple act of fusing the fibers into one unified unit. Similar to many organizational systems in nature, such an approach in construction can produce structurally stable forms that more efficiently distribute loads within a structure. As well as, result in a higher degree of freedom to position and add new elements with endless possibilities according to structural or functional constraints thus providing the designer with more control on the overall form. Accordingly, these light-weight, unbreakable structures are what this research will investigate in hopes to create architecture that uses less material and eventually instigate for integrated, continuous structures.
The following sections will explain how materiality can inform structure creating continuous fabric formations in architecture.
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Felt fabric spatial divider ( Author’s own, 2016)
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3.1 Material Continuity Architecture is where materiality and spatial human experiences exist to interact with each other. They affect each other and influence the resulted behavior taken place in between. In the Architecture of Continuity, Lars Spuybroek refers to Gothic architecture as the ultimate continuous form of design where both structure and ornamentation are merged into one. And where continuity is achieved through materiality and through scale variation and so is considered to be one entity rather than of aggregated components. The whole design works on a system of scale variation where a column can easily transition into a vault and then weave together to form a ceiling structure. Spuybroek describes this system as one where its elements continuously vary in states yet maintaining a constant relationship between them all. Eventually, Lars proposes for a relationship logic based on a continuous sense of materiality that creates the whole and not just the parts. This kind of architecture is what fuses the hard with the soft, and the material with construction (Spuybroek, 2008). In this project, the materiality of felt fibers was explored in two different ways, through the physical control of material deposition and manipulation. The advantage to any designer of being able to control the physical quantity and behavior of any material offers a deeper understanding of how it performs locally and globally within the whole.
3.1.1 Material Control Inspired by the ability of natural systems to control the distribution of fibers according to their dynamic surroundings, in this project felt fibers were similarly controlled by manipulating fiber density and layering depending on their structural performance. Accordingly, the different elements were segregated by thicknesses, the structural elements were assigned as the hard inner tubes and the soft layers as the surfaces or enclosures.
The transition of hard to soft or tube to surface is how the different layers were primarily identified. The merging of both layers was initially explored by reinforcing a single material sheet of felt fibers with a pattern of same size inner tubes. To create a difference in thicknesses. the same size tubes were bundled into thicker layers to be able to withstand different loads similar to the bundling of fibers in bamboo. The below prototype demonstrates how multiple tubular twisted sheets were connected by needle felting and the thicknesses varied depending on the number of tubes bundled together.
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Continuous prototype ( Author’s own, 2016)
1. Global deformation :
Forms bigger curves that are flexible for folding
2. Structure :
Bundled veins create a stiff surface for support & structure
3. Local deformation :
Forms smaller curvatures with more controlled curvature
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Comparable to the bamboo fibers, the more the thick tubes were bundled, the more the fibers are interlocked and so locally manipulating the strength of the connecting fibers. However, the first approach was experimenting with the limits of the fibers alone and so created weak pieces that went bad quickly. In those experiments, it was deduced that fibers can’t withstand to bear loads and can’t perform structurally alone. As such, to develop larger prototypes, a new layer of material was introduced to reinforce the fibers.
The expandable foam was a very useful material to use since it was light weight and easily formed into the required shapes. It also was very helpful when combining it with the fibers since they could easily be infused in the foam due to its penetrable natural. The thin coat of fibers was easily merged with the foam using the same needle felting technique forming a new multilayer composite of material that is stronger and more durable. The expandable foam reinforced the fibers but also eliminated the need for hardening the fibers and thus the natural soft texture of the fibers was maintained. And so what appeared to be a multilayer material system, in fact, turned into a single infused layer of a reinforced fibrous structure that maintains the unique textural properties of felt fibers and smoothly transitions from soft to hard within one continuous hybrid material.
The below prototype demonstrates how the hardened tubes were bundled to increase the strength and thickness of the fibrous layers at the transition points where they branched out to form the thinner surface. The different layers vary in scale and in performance all while maintaining the continuous transition of a tube to surface.
1. The tubes were connected at the legs
for more strength. By combing (bundling) multiple tubes together, the overall leg is reinforced.
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2. The tubes at the legs also branch out to
connect with adjacent legs. The whole pattern was a continous flow of tubes as to avoid any breaking when foaming
3. As for the seating area another linear
component was connected perpendicular to the stool structure to accommodate for the surfaces needed in that area.
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Tubular stool ( Author’s own, 2016)
3.1.2 Materiality in fabrication As the research progressed, the modern technology of robotic programming was utilized to assist in achieving a higher accuracy in the gradient of textures and thicknesses. A specialized end effector was designed and attached to the robotic arm to pass through the felt fibers at alternating speeds and needle felting programmatic gradients within a single sheet of felt fibers. The below table demonstrates different speed patterns and their corresponding gradient textures. This approach allowed for an advanced level of material control introduced into the fabrication process and thus further reducing material waste by knowing exactly how many layers of fibers were needed and how much time was required to felt them into soft or hard material. [ Fabrication Logic ] In order to create an accurate gradient of textures, the robot was programmed to change its speed and number of passes through the wool fibers.
Sample
Speed pattern
01
Fast, Slow, Fast
Low, High, Low
6, 2 , 6
1 , 2, 1
02
Number of overlaps
Slow, Fast, Slow 2, 6, 2
03
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Soft
Hard
Soft
Hard
Soft
Hard
Soft
Soft
Hard
High, Low, High 2, 1, 2
Fast, Slow, Slow 2, 6, 2
Gradient pattern
High, Low, High 2, 1, 2
Robotic felting patterns ( Author’s own, 2016)
[ Felting needles move in a vertical motion through the wool fibers interlocking them into a solid sheet of felt fabric ]
Needle felting end effector ( Author’s own, 2016)
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| Robotic Fabrication Robot : ABB120 Felting Time : 3.5 hours Advantage : Efficient in creating a continuous gradient of various textures among felt fibers.
3.2 Structural Continuity Structural systems rely mostly on the way it’s various elements are connected together. Discontinuous systems are the most commonly used structural frames these days. Such arrangements are simple and cost effective yet they are not efficient in terms of material use since they require larger elements to withstand large amounts of internal loads. These types of systems also restrict designers to structures that are of regular geometries that require traditional steel work. On the other hand, continuous structures behave differently. Even though they are complex and more difficult to construct, such structures reduce material waste and are thus more efficient. They also allow for more design freedom and overall greater stability by simply reducing the number of connections between the various structural elements (Macdonald,1994). The figure below illustrates the difference between discontinuous and continuous structural systems.
Since fibers components are easy to connect, structural continuity can simply be achieved in larger woven assemblies. By taking advantage of the natural materiality of felt fibers, this project was able to demonstrate how different elements can be joined together into what seem like a single unit. The connection points between the various elements were kept to the minimum and were easily disguised since the tubes were connected at their edges rather than their end points. By dissolving the divisions between the different components and infusing the multilayer materials into a single composite, a continuous structure was created.
The above chair is an example of how various components were connected at assigned points along a thick inner structure. It also demonstrates the variation in scale between the load-bearing tubes and smaller bundled tubes that spread out to accommodate the surface layer. As such, the materiality of felt fibers was reflected on a larger assembly to create a self-standing chair of multiple components and eventually achieve an overall continuous structure.
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Discontinuous and Continuous Structures (Macdonald, 1994)
Continuous surface chair ( Author’s own, 2016)
1. Structure:
Veins are concentrated in the seating area and back rest in order to transfer the loads to the volumetric part of the chair. As well as, assist the chair to stand on its own.
2. Volume:
Volumetric part to absorb loads is composed of multiple surfaces merged into layers of felt.
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Chapter 4 | FleXtiles
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4.1 Studio Research The intent of this research project is to physically investigate the natural characteristics of felt fibers in creating fabric architecture without stitching or using glue. This research will highlight the possibilities of using such a natural material to go beyond building simple tent-like structures to functioning as structural elements in architectural design. Taking inspiration from the previously mentioned topics, The project investigated many approaches where the natural materiality of felt fibers was merged into the development of the design and fabrication processes to potentially redefine the use of fabric in architecture. The following sections will further elaborate how that was carried out within the design studio.
4.2 Initial Studies Inspired by organic forms in nature, Stephanie Metz mostly experimented with the craft of needle felting to sculpt using wool fibers. These felted sculptures offered an insight to this research on the true potential of felt fibers in creating volume and stiffness out of a naturally soft material. Thus the initial approach included various experiments to understand the general behavior of felt fibers and it’s many qualities were noted throughout these trials that further assisted in discovering the potential of felt fibers in creating structurally designed elements.
Stephanie Metz felted wool sculptures ( Bertus Pieters, 2015) .
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Some early on investigations involved combing both techniques of wet and needle felting, to customize and shape the fibers into various forms by simply building up overlapping layers of fibers into three dimensional woven prototypes. However, to further understand how the felted fabric can transform from a flat sheet into three dimensional forms, a new layer of felted linear elements was introduced. This inner structure was integrated within the sheet of fibers and the resulting material became a single reinforced unit suggesting a homogeneous material system. Multiple pattern studies of the inner structure were tested and the different number of linear elements, as well as their arrangement according to each other, affected the flexibility of the felted sheet thus creating different three dimensional forms.
The below prototypes demonstrate how by twisting and connecting the inner structure, the single felted sheet was formed into various shapes with different levels of curvature and stability.
Felted prototypes ( Author’s own, 2016)
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The project further experimented the versatility of felt by customizing multiple layers of reinforced sheets together and forming them into various shapes. By entangling the fibers at connection points, the joints were strengthened and thickened as opposed to the fibers on the outer peripheries which were thinner and more flexible.
This development introduced how different layers of felt could be locally manipulated to create a gradient of different textures and thicknesses within a single sheet of material which we related back to material systems found in nature.
Multilayer prototype ( Author’s own, 2016)
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4.3 Fabrication Development The need for an inner structure is evident from conventional fabric buildings. However, unlike previously referenced textile structures, this project focuses on how the fabric membrane can be infused into its reinforcement. From the initial experiments it was discovered that the felted fibers alone could not withstand loads and needed further support of a different kind of material. And so, expandable foam was introduced as a new material layer to the fabrication process to assist in creating larger self-standing prototypes.
Similar to traditional techniques of fabric casting, the expandable foam was injected into flat patterns of industrial felt sheets. This created the required volume without the need for needle or wet felting excess layers together and so it saved material as well as fabrication time. The foam is also lightweight and extremely flexible to easily shape into various double-curved forms and so designed into the structural tubes.
In order to fabricate larger assemblies, the need for a component based approach was apparent due to limitations in the newly introduced material. When experimenting with the expandable foam it was discovered that it easily fused with the fibrous fabric material making it difficult to span inside large components. Casting the foam also required exterior scaffolding to hold and shape the patterned fabric in place. However, despite introducing a new material to the system, the penetrable nature of the expandable foam still allowed for the felt to preserve its unique materiality. The felted coat of fibers was thus easily needle felted and infused into the foam creating the surfaces needed for enclosures.
To further develop this approach for the upscaling of prototypes, various loads were digitally analyzed and simulated to differentiate where thick and thin layers were allocated. By being able to control where the material layers can be deposited, variations in the scale of the inner structure were easily achieved and thus creating a continuous structure of structural tubes and thin surfaces similar to the previously mentioned continuity of Lars Spuybroek.
The diagram below illustrates how the deformation analysis was translated into a variation of fiber densities within a designed chair. This information allocated where the inner structure thickens according to structural loads. It was evident that the amount of fiber and density increased in the more load bearing members as opposed to the more porous layers that required less material.
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[ The process of hanging ] [1]
[2]
[3]
Hanging Progress = 0%
Hanging Progress = 15% Repelling Range = 30.0 Spring Stiffness = 0.2
Hanging Progress = 30% Repelling Range = 60.0 Spring Stiffness = 0.2 Height = 70 cm
Repelling Range = 0.0 Spring Stiffness = 0.2 Height = 0 cm
[4]
Height = 40 cm
[5]
Hanging Progress = 60% Repelling Range = 120.0
Hanging Progress = 85%
Spring Stiffness = 0.2 Height = 90 cm
Spring Stiffness = 0.2 Height = 90 cm
Repelling Range = 170.0
[6]
Hanging Progress = 100% Repelling Range = 200.0 Spring Stiffness = 0.2 Height = 90 cm
Digital process of transformning 2D to 3D patterns ( Author’s own, 2016)
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[ Inner structure optimization ]
[ Back Load ]
[ Hand Load ]
[ Hand Load ]
[ Seat Load ]
[ Foot Support ]
[ Foot Support ]
Digital load analysis on three dimensional form ( Author’s own, 2016)
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[1]
[2]
[3]
Analysis Progress = 0%
Analysis Progress = 100%
Analysis Progress = 50%
Maximum Deformation Value = 0.00
Maximum Deformation Value = 14.50
Maximum Deformation Value = 10.17
Average Deformation Value = 0.00
Average Deformation Value = 2.19
Average Deformation Value = 1.38
[0.00]
[15.00]
Optimization process ( Author’s own, 2016)
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[ Material used ]
. Expandable foam:
. Felt fibers:
. Felt sheets:
. Plastic tubes
In order to expand into a three dimensional form
Used to connect the felt sheets together without the need for stitching or glue.
Used for the overall form and shaping.
To help maintain the shape of the tubes prior to the injection of foam
The analysis informed the fabrication process of the necessary quantity of fibers needed in the load bearing areas of the large scale prototypes. This information was reflected in the physical realm in terms of tube thicknesses and hard textures for the structural elements as opposed to the thinner and softer textures for the surface layer. The designed chair prototype below demonstrates the variation in scale between the load bearing tubes and smaller bundled tubes that spread out to accommodate the surface layer as well as the continuity achieved from the felt/foam composite.
The continuity was still maintained when the different components were combined together to form the overall chair. Using the needle felting technique the components were fused together along with the felted surfaces layer. Since the thicknesses of the fibrous sheets were manipulated , different kinds of surfaces with different types of performance abilities were created. The thinnest surfaces that were attached gathered and curled to form more soft textures in between the hard tubes. and so these surfaces were allocated on the seating and back area to add extra comfort to the chair.
In conclusion, the materiality of felt fibers proposed new potential for the development of traditional fabrication techniques of textile structures in architecture. By reinforcing the inner support with the natural strength and resilience of felt fibers, more homogeneous and continuous prototypes were fabricated. With these developed fabrication techniques, the research intends to revolutionize the traditional craft of felt-making to create a new building block of natural materials within the field of architectural design.
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Physical chair - Front view (Author’s own, 2016)
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Chapter 5 | Future Recommendations
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The research aims to propose for an evolution of materiality in design to develop more optimized, and eventually stronger structures. Defying traditional discrete building typologies, it suggests for an integrated architectural design approach to create continuous self-standing shell structures composed of a multi-layer architectural system of surfaces and structure seamlessly merged together.
Inspired by material organizations in nature, a systematic approach was presented to develop innovative systems for the construction of fabric architecture that unifies materiality, and fabrication in a continuous integrated design process. Michael Weinstock elaborates more on how such an ideology can be implemented in engineered structures of architectural scale by abstracting the main complexities behind the material structures of natural systems.
Unlike conventional structures that rely on the standardization of segregated components and elements, natural systems function with higher levels of structural performance that depend on the interaction of a multilayer material organization. The inner arrangement of material distribution and behavior is the source for the efficient functionality of such biological structures. Understanding the complexity behind such unique models found in nature, Weinstock proposes to reflect this intelligence on to architecture by establishing a stronger relationship between the design elements on different organizational levels thus achieving a system that is greater than the sum of its parts (Weinstock, 2006).
This understanding of materiality goes beyond the continuity defined by Lars Spuybroek in The Architecture of Continuity where materiality is achieved in the variation of just size or scale in relation to other architectural elements. Whereas Weinstock suggests that a more complex level of continuity can be achieved on different material organization levels as well as between the different components of the structure thus affecting the global morphology of the overall form. The variation in materiality on different layers ensures a constant relationship among the inner organization of each connected element (Weinstock, 2006). Since wool fibers are versatile and can be manipulated in a similar way, this hierarchy of material control among different levels can be achieved to ultimately develop strong continuous forms out of soft fibrous fabric.
Architecture is customarily regarded as an assembly of parts, however, by developing such an approach in architectural design each part can function interdependently together to create new levels of functionality as a whole. Researchers at the Institute for Computational Design (ICD) took on this approach and fabricated a high-performance pavilion constructed out of a combination of carbon-fiber and glass composites. By replicating fibrous systems found in nature, the fibers were carefully arranged according to a programmed gradient of thicknesses and stiffness. The two different types of synthetic fibers were also oriented according to a specified hierarchy in transparency and performance. The resulting configuration easily transitioned between different states and materiality resulting in a structurally stable shell structure (Bojovic, 2013).
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The studio research develops similar fabrication tactics in which the wool fibers are distributed and strengthened in areas that are load bearing as opposed to the thinner surfaces which create more porous enclosures. Assigning such functional variations within local elements is reflected within larger assemblies. This complex integration of material and structure will increase the overall efficiency while minimizing material consumption in developing homogeneous structures in architecture.
ICD reserach pavilion (Bojovic, 2013) | 47
Conclusion Textiles in architecture have played a big role in the development of light-weight, adaptable structures throughout history. The high level of versatility in forming and shaping fabrics has been very intriguing to designers of all fields. Especially in architectural design, this kind of material has great potential in creating newly defined spatial mediums. By using historical references of past textile structures combined with technological advancements nowadays, architecture can take advantage of the hidden potentials of customizing textiles to increase overall performance and structural ability of such structures.
However, the opportunities of creating structure and form from the raw material of textiles have yet to be fully explored. By going beyond ready-made flat sheets of felt fabric, this research proposes the use of felt fibers to rather explore three-dimensional forms with the same versatile characteristics that can easily be controlled according to the way the fibers are processed. This is an extreme advantage to designers since it provides the freedom to control the material on a local scale to behave differently at different moments throughout the design and eventually minimizes material wastes and fabrication limitations.
By also taking inspiration from material systems found in nature, this research highlights how the materiality of felt fibers can inform the fabrication and design of homogeneous structures in an integrated architectural design approach. The continuous complexities running through the system redefines the potential of fabric in architecture.
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Digital design (Author’s own, 2016)
References . Biotechlearn.org.nz. (2010). Wool fibre properties | Biotech Learning Hub. Available at: http://biotechlearn.org.nz/focus_stories/wool_innovations/wool_fibre_properties . Dobnik Dubrovski, P. and Brezocnik, M. (2012). The Usage of Genetic Methods for Prediction of Fabric Porosity. . Geoffanderson.com. (2011). Available at: http://www.geoffanderson.com/kat16-Fabrics/side318-Merino-wool.html . Kamath, M. (2004). Available at: http://www.engr.utk.edu/mse/Textiles/Needle%20Punched%20Nonwovens.htm . Koester, A. (1993). The Structure Of Textile Fabric. . Kuusisto, T. (2012). Textile in Architecture. Master’s Thesis. Tampere University of Technology. . MacDonald, A. (1994). Structure and architecture. Oxford: Butterworth Architecture. . Spuybroek, L. (2008). The architecture of continuity. Rotterdam: V2 Pub. . Weaver, M. (2005). Tension Fabric: Waves of the future. (1). . Weinstock, Michael. “Self-Organisation And The Structural Dynamics Of Plants”. Architectural Design 76.2 (2006): 26-33
. Bojovic, M. (2013). Researching New Tectonic Possibilities In Architecture / Robotically Fabricated Pavilion In Stuttgart - eVolo | Architecture Magazine.
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University College London Bartlett School of Architecture 2015-2016