October 2015  Trevor Langford

 

 

 

 

ABSTRACT

 

Since Vitruvius started designing buildings people have been trying to mimic Nature. Today computers can assist in designing organic structures using complex algorithms which has allowed it to become even easier to mimic Nature in architecture. There is a risk in mimicking natural forms by purely replicating their aesthetic form. The Beijing Watercube (2004-2007 Beijing, China) replicates the structure and appearance of bubbles but not the free organic form when they form clusters, its as if the bubbles were bound by a simple glass box (see Fig.1). Analysing the method of mimicry used in the Watercube, by investigating other examples of soap bubble experiments and inspired designs this paper will explore how computers can assist in designing organic structures. Before computers, Plateau’s experiments with soap films (1858-1873) creating Plateau’s rules for soap films and Frei Otto’s roof system for the Munich Olympic Stadium (1972 Munich, Germany), these practical experiments test and calculate the inherit structural integrity of Nature’s building code. Investigating these examples will prove that computers aren’t needed to design organic structures. However this code can now be calculated by computers using algorithms, and used to help and more easily design structure. The world is turning more and more to computers to experiment and create digitally. Just because a computer does the experiment to calculate the organic form does that mean we shouldn’t do practical form finding experiments? The Watercube is an example of computer designed Nature, which is practically tested via small scale experiments and art installations. Chris Bosse and LAVA often use small scale experiments and art installations to test large scale designs. Through an analysis of interviews with Chris Bosse and investigation into experiments and art installations in supporting the Watercube design this paper will argue the importance of practical experimentation and understanding of Nature’s building code for contemporary architecture.

 

 

 

Introduction

 

Since humanity started designing buildings, shelter and machines, designers have been turning to Nature for inspiration and answers to the problems that arise when creating something new. ‘Architectural principles are imitations of the processes of Nature.’[1] The primitive hut introduced by Vitruvius, and later recaptured by Marc Antoine Laudier who

 

‘believes in absolute, ‘essential’ beauty… this beauty is to be found in Nature alone; it is from Nature that all rules are derived’1.

 

The primitive hut depicted in the frontispiece of Laudier’s ‘Essai sur l'architecture’(1755) illustrates a simple hut with trees as its structure, a literal interpretation of using Nature to design and build. Confirming designers have investigated Nature for the rules of building and design. Mimicry of Nature is used not only in the structure of a building, also in its ornament, as depicted in the capitals of Corinthian columns in which stone is carved to aesthetically copy the form of unfurling fern leaves and other broad leaves. There is a risk of mimicking forms in Nature by purely replicating the aesthetic image of something.[1] Further investigation into Natures appearance is required to understand the rules behind its form, those rules should then be applied to help inform the design process.

 

Before computers, to find out Nature’s rules or building codes Scientists and Architects create physical experiments, such as Plateau’s soap film experiments (1858-1873) and Frei Otto’s soap film experiments to design the roof system of the Munich Olympic Stadium (1972 Munich, Germany). ‘The study of soap bubbles greatly helps the understanding of pneumatic structures.’[1] Pneumatic structures are one of the fundamental structural forms in Nature, found in the fruits of plants, air bubbles, in animals blood vessels, and even within skin kept taught by muscles and blood pressure. Pneumatic structures are structural forms stabilised and shaped by the pressure differences of liquids, gases, foam, or material in bulk. As the mere studies of soap bubbles relates to a fundamental structural form of Nature, Plateau and Frei Otto achieve a lot of insight into the building code of Nature. Through the investigation of these experiments this essay will provide evidence of Natural form design through physical experimentation without the use of computers.

 

‘Form-finding, which takes place through physical and digital modelling, with physical models being at a reduced scale, introduces functional models to the toolset of architectural design.’

 

 

When architects are using computers more and more to digitally model and experiment, is there still a place for physical form finding experiments? The Beijing Watercube (2004-2007 Beijing, China) designed by PTW architects, with Chris Bosse as a leading architect, is a case study in which parallel to the designing of the structure a form finding experiment was conducted. The overall form of the Watercube was chosen to be square in nature to juxtapose the circular Bird’s Nest stadium (2004-2007 Beijing China) situated opposite the site, this form of circle (Bird’s Nest) and square (Watercube) represents the Ying and Yang of Chinese culture. The soap bubble, foam based structural design within the form is to represent water molecules as the Watercube houses the aquatics centre. The soap bubbles seem to be bound by a clear cube, the edges connecting the vertices where the bubbles meet form the skeleton of the structure (Fig. 1)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 1: Analytical diagram of Watercube structure

 

‘Despite its apparent complexity and its organic form, the building is in fact built using a high degree of repeatability. The use of only three different faces, four different edges and three knots or different angles’[1]

 

Using computer aided design software the form and structure for the Watercube was produced. During the same period of time students in a master class at the University of Technology Sydney lead by Chris Bosse researched modern trends in algorithmic design and created an art installation, ‘Digital Origami’, to embody a new architectural space. This experiment in form finding generated a scaled model of the architectural space to be designed within the Watercube. Through the analysis and further investigation of this experiment this paper will argue the importance of physical form finding experiments. This paper will first take investigate the experiments of Plateau and Frei Otto to determine that it is possible to ascertain the rules behind the creation of organic forms in Nature and the possibility of replicating such forms in architecture. Secondly this paper will analyse the case study, the Beijing Watercube, and its parallel form finding experiment to argue that even when computer is used to help, more easily design organic structures a physical form finding experiment is also beneficial to the development of such architecture.

 

 

Plateau’s soap film experiments

 

Antoine Ferdinand Plateau was a scientist, he began his career in the scientific field of astronomy. During one of his experiments his eyes were irreversibly damaged from staring at the sun for an extended period of time. He was diagnosed as blind in 1843, which turned his interest to the nature of forces in molecular fluids. After 15 years of research in 1873 he published his findings in two volumes: ‘Statique exp´erimentale et th´eorique des liquides soumis aux seules forces mol´eculaires’.

His experiments with soap films were to solve what is known today in the mathematics’ world as Plateau’s problem;

 

‘is to consider a curve in any space and try to find the surface that has that curve as a boundary and has the lowest possible area.’[1]

 

At first Plateau considered the forms obtained when air is blown into a soapy liquid, which doesn’t create perfect separate spherical bubbles instead creates an

 

agglomeration of almost flat soap films that separate bubbles of air. Using pipettes more air is blown into the soapy liquid, creating a more complex agglomeration of soap films. Plateau observes that however high the number of films that arise there are only two possible types of configurations (rule 2). From his observations Plateau deduces three rules of soap films:

 

1. a system of bubbles or a system of soap films attached to a supporting metallic wire consists of flat or curved surfaces that intersect with each other along lines with very regular curvature;

2. surfaces can meet only in two ways: either three surfaces meeting along a line or six surfaces that give rise to four curves that meet in a vertex;

3. the angles of intersection of three surfaces along a line or of the curves generated by six surfaces in a vertex are always equal in the first case to 120◦ (Fig. 2 in red), in the second to 109.47◦ (Fig. 2 in yellow). [1]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 2: Angles of the intersection of soap films 120o (red) 109.47o (yellow)(Image courtesy of Mihail-Andrei Jipa, University of Westminster, School of Architecture and the Built Environment.)

 

Using these rules Plateau experimented with three dimensional wire frames, dipping them in a soapy liquid, when the wire frames are removed from the soapy liquid a system of soap films connect each wire. The result is the physical solution to ‘Plateau’s problem’ for each individual three dimensional wire shape. Plateau’s publishing’s prove that Nature’s code can be calculated without the help of computers and these laws are adhered to into the modern day to provide the basis of experiments, both physical and digital, to find minimum surface areas.

 

 

Frei Otto’s Olympic stadium

 

Frei Otto researched and experimented with tensile structures, he compiled his research and the research of mathematicians and engineers into two volumes: ‘Tensile structures; design, structure and the calculation of buildings of cables, nets, and membranes’ volume one was published in 1962 and volume two was published in 1966.

 

‘A knowledge of minimum surfaces is important in the design of membrane and cable-net structures. However, minimum surfaces are not always the optimum structural shapes. A minimum surface defines only the surface of least area within a closed curve. A minimum surface is identical with a membrane everywhere uniformly stressed in all directions.’[1]

 

Each individual soap bubble or agglomeration of soap bubbles has at each point and in every direction equal membrane stresses. Hence soap bubbles or films will always assume the form that has the least possible surface area, the minimum surface area. In research for the design and construction of the Munich Olympic Stadium (1972 Munich, Germany) Otto looked back to his previous works and experiments within his book ‘Tensile Structures’. In particular the soap film test with composite surfaces boarded by cables, these tests explore the forms and theories behind the roof structure of the Munich Olympic Stadium. These tests involve using nails on a board, hammered to specific combinations of low and high points with thread connecting each head of the nail to form an enclosed boundary, additional threads are used to connect similar apposing points to help create further shapes (Fig.3). From the froms created with soap films a rubber thread test of the desired form can be made (Fig. 4) however this threaded model doesn’t have to obey Plataues laws of soap films and minimal surface, so the resulting form is a greater surface area.

 

 

 

 

 

 

 

 

 

 

 

Figure 3:Frei Otto's soap film experiments (Sourced: Otto, Frei, Rudolf Trostel, and Friedrich Karl Schleyer. Tensile Structures; Design, Structure, and Calculation of Buildings of Cables, Nets, and Membranes. Cambridge, Mass.: M.I.T. Press, 1967.)

 

 

 

 

 

 

 

 

 

 

 

 

Figure 4: Soap films and rubber thread models (Sourced: Otto, Frei, Rudolf Trostel, and Friedrich Karl Schleyer. Tensile Structures; Design, Structure, and Calculation of Buildings of Cables, Nets, and Membranes. Cambridge, Mass.: M.I.T. Press, 1967.)

 

‘Any shape which a soap bubble can assume can also be obtained as a pneumatic structure. Any envelope, forming an enlargement to scale of a soap bubble shape can be made of slightly deformable skins, such as glass fabric or paper.’[1]

 

From these form finding models it is possible to calculate and scale up the design to a life size construction, proving once again that it is possible to design a structural form from Nature without the use of computers.

 

 

 

 

Chris Bosse – parallel designing

 

The design of the Watercube is imbedded in the concepts set forth by Lord Kelvin in 1887, when he asked ‘how space could be partitioned into cells of equal volume with the least possible area of surface between them’[1], known as the Kelvin problem. Adhering to the aforementioned rules set forth by Plateau’s experiments, Kelvin proposed a foam based on the bi-truncated cubic honeycomb composed of truncated octahedrons, which have 6 square faces and 8 hexagonal faces that are slightly curved conforming to Plateau’s laws of soap films. Kelvin’s proposed foam composition is known as the Kelvin structure and for over 100 years believed to be the optimal solution to the ‘Kelvin problem’. In 1993, the physicist Denis Weaire and his student Robert Phelan from Trinity College, Dublin, discovered through computer simulations a new foam structure that had 0.3% less surface area than the ‘Kelvin structure’. The new found foam structure, the Weaire-Phelan structure, differs from the ‘Kelvin structure’ as it consists of two different kinds of cells of equal volume. The first cell is an irregular dodecahedron with pentagonal faces, which possess tetrahedral symmetry. The second cell is a tetrakaidecahedron with two hexagonal and twelve pentagonal faces possessing antiprismatic symmetry. Conforming to Plateau’s laws the pentagonal faces are slightly curved in both cells.

 

Chris Bosse stated:    

                                                                                           

‘The structure of the Watercube, National Swimming Center in Beijing was based on the possible most efficient division of three-dimensional space. It is a scheme extremely widespread in nature (for example, it is the way in which cells are disposed, the shape of structure of crystalline mineral, and how soap bubbles form). Lord Kelvin had posed at the end of the nineteenth century the problem of dividing space into three-dimensional multiple compartments, of equal volume, and finding the form they would have if the surface area of the interfaces should be minimal. The study of soap bubbles is a good starting point for considering the challenge of Kelvin.’[1]

 

In parallel to the designing of the Watercube, students from the University of Technology Sydney’s master class lead by Chris Bosse, were asked to research and explore the current trends in parametric modelling, digital fabrication and material science and to apply the gained knowledge to a space filling installation. The aim of the master class was to test modules copied from Nature in the generation of an architectural space through the smallest elements of design (i.e. foam structure). The end result ‘Digital Origami’ project was displayed in the Erskine gallery, Sydney (2007). The installation used the same cells of the ‘Wearie-Phelan structure’ built from recycled card to redefine and create an intriguing architectural space which uses the same principal of linear repetition as the Watercube only at different scales (Fig. 5 and Fig. 6).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Source: http://www.l-a-v-a.net/

Figure 5: Digital Origami Project (Sorced: http://www.l-a-v-a.net/)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Source: http://www.l-a-v-a.net/

Figure 6: Beijing Watercube interior

 

 

 

 

The installation gives a life size, physical experience of the architectural space that is being proposed in the Watercube, even though the scale of the cells are different the spaces created are almost the same, as the form of the cells used as building blocks lead the design of  the inherent architectural space that follows.

 

 

Conclusion

 

From the workings of Vitruvius and Laudier in 1755 through to the buildings and art installations of Chris Bosse today, there is no doubt designers and architects have been trying to capture the beauty and form of Nature. Today with the most current form finding methods, including both digital and physical, result in generating systems defined by:

 

‘curved geometries, whether minimal surfaces, pneumatic structures, tensile-stressed suspended forms (linear elements -catenaries; flat elements- suspended nets), compression-stressed inverted forms (linear elements -standing chains, thrust lines; flat elements-thrust surfaces, grid shells), this also applies for natural structures such as tensile-stressed (for membrane-forming materials) and compression-stressed material conglomerations (rubble heaps, drain funnels, caves, erosion formations), as well as structures in space and time (waves, systems subjected to vibrations, vortices and turbulence) whether in living or non-living nature.’[1]

 

It is easy to see how computers can help with the calculations and design of these forms found in Nature, however when a design is solely based in digital form does it detract from the potential of the architectural space. Through the investigation into Plateau’s experiments (1755) this paper has shown how it is possible to discover and calculate Nature’s building code. Through the investigation into Frei Otto’s experiments (1966) we came to the conclusion that a model physical experiment can be calculated and scaled up to create a life size construction. Through the analysis of the case study, the Beijing Watercube, and its relationship to the parallel art instillation ‘Digital Origami’ the paper has confirmed the positive attributes of physical form finding in parallel conjunction to digital form finding.

 

 

 

[1] Kruft, Hanno-Walter. A History of Architectural Theory : From Vitruvius to the Present.  London : New York: Zwemmer ; Princeton Architectural Press, 1994.

[1] Veitch, Michael, Fenella Kernebone, and Chris Bosse. Chris Bosse: Fenella Kernebone Talks to German-Born Architect Chris Bosse, Director of Lava, the Laboratory for Visual Architecture Based in Sydney, Australia. 2009.

[1] Otto, Frei, Rudolf Trostel, and Friedrich Karl Schleyer. Tensile Structures; Design, Structure, and Calculation of Buildings of Cables, Nets, and Membranes.  Cambridge, Mass.: M.I.T. Press, 1967.

[1] Hensel, Michael & Menges, Achim. "Morpho-Ecologies – Towards an Inclusive Discourse on Heterogeneous Architecture ". Chap. Part 1 In Morpho-Ecologies, edited by Michael & Menges Hensel, Achim, 16–61. London: Architectural Association, AA Agendas No.4, 2006.

[1] Emmer, Michele. “Matematica E Cultura 2007: A Cura Di Michele Emmer.” Chap. L’architettura delle bolle di sapone edited by Bosse, Chris, 43-56. Matematica E Cultura. 2007.

[1] Emmer, Michele, Alfio Quarteroni, and SpringerLink. “Mathknow Mathematics, Applied Sciences and Real Life.” Chap. Soap films and soap bubbles: from Plateau to the Olympic swimming pool in Beijing edited by Emmer, Michele, 119-129. Milano: Springer Milan, 2009.

[1] Emmer, Michele, Alfio Quarteroni, and SpringerLink. “Mathknow Mathematics, Applied Sciences and Real Life.” Chap. Soap films and soap bubbles: from Plateau to the Olympic swimming pool in Beijing edited by Emmer, Michele, 119-129. Milano: Springer Milan, 2009.

[1] Otto, Frei, Rudolf Trostel, and Friedrich Karl Schleyer. Tensile Structures; Design, Structure, and Calculation of Buildings of Cables, Nets, and Membranes.  Cambridge, Mass.: M.I.T. Press, 1967.

[1] Otto, Frei, Rudolf Trostel, and Friedrich Karl Schleyer. Tensile Structures; Design, Structure, and Calculation of Buildings of Cables, Nets, and Membranes.  Cambridge, Mass.: M.I.T. Press, 1967.

[1] Emmer, Michele, Alfio Quarteroni, and SpringerLink. “Mathknow Mathematics, Applied Sciences and Real Life.” Chap. Other geometries in architecture: bubbles, knots and minimal surfaces edited by Wallisser, Tobias, 91-111. Milano: Springer Milan, 2009.

[1] Emmer, Michele. “Matematica E Cultura 2007: A Cura Di Michele Emmer.” Chap. L’architettura delle bolle di sapone edited by Bosse, Chris, 43-56. Matematica E Cultura. 2007.

[1] Hensel, Michael & Menges, Achim. "Morpho-Ecologies – Towards an Inclusive Discourse on Heterogeneous Architecture ". Chap. Part 1 In Morpho-Ecologies, edited by Michael & Menges Hensel, Achim, 16–61. London: Architectural Association, AA Agendas No.4, 2006.

 

 

 

BIBLIOGRPAHY

 

Emmer, Michele, Alfio Quarteroni, and SpringerLink. “Mathknow Mathematics, Applied Sciences and Real Life.” Chap. Soap films and soap bubbles: from Plateau to the Olympic swimming pool in Beijing edited by Emmer, Michele, 119-129. Milano: Springer Milan, 2009.

 

Emmer, Michele, Alfio Quarteroni, and SpringerLink. “Mathknow Mathematics, Applied Sciences and Real Life.” Chap. Other geometries in architecture: bubbles, knots and minimal surfaces edited by Wallisser, Tobias, 91-111. Milano: Springer Milan, 2009.

 

Emmer, Michele. “Matematica E Cultura 2007: A Cura Di Michele Emmer.” Chap. L’architettura delle bolle di sapone edited by Bosse, Chris, 43-56. Matematica E Cultura. 2007.

 

Hensel, Michael & Menges, Achim. "Morpho-Ecologies – Towards an Inclusive Discourse on Heterogeneous Architecture ". Chap. Part 1 In Morpho-Ecologies, edited by Michael & Menges Hensel, Achim, 16–61. London: Architectural Association, AA Agendas No.4, 2006.

 

Kruft, Hanno-Walter. A History of Architectural Theory : From Vitruvius to the Present.  London : New York: Zwemmer ; Princeton Architectural Press, 1994.

 

Otto, Frei, Rudolf Trostel, and Friedrich Karl Schleyer. Tensile Structures; Design, Structure, and Calculation of Buildings of Cables, Nets, and Membranes.  Cambridge, Mass.: M.I.T. Press, 1967.

 

Veitch, Michael, Fenella Kernebone, and Chris Bosse. Chris Bosse: Fenella Kernebone Talks to German-Born Architect Chris Bosse, Director of Lava, the Laboratory for Visual Architecture Based in Sydney, Australia. 2009.