Constructing Shadows – Pergolas, Pavilions, Tents, Cables and Plants

Contents Essays 7 8 12 22 44 50 54 58

Introduction Peter Petschek, Siegfried Gass Plants — Shadow Peter Petschek Constructive Design of Small Buildings: Handbook Fabienne Kienast Weber, Peter Petschek Pergolas: Functions, Forms, and Construction Elements Hans-Joachim Liesecke Shade-providing Small Buildings in Landscaping and Landscape Architecture Julia Burbulla Cables in Landscape Architecture: The MFO Park Markus Fierz Teaching About Shadows Nancy Yen-wen Cheng, Joachim B. Kieferle Shade-providing Tents: On the Design and Construction of Lightweight Canvas Structures Siegfried Gass

Plants 72 74

Overview Plants Clinging Rootlets, Creepers, Twiners, Tendrils, and Scrambling Climbers Maja Tobler, Olivier Zuber

Projects 116 122 245 246

Overview Projects Projects Biographies Sources and Bibliography

Plants — Shadow

the connective tissue of the dermis, and From a building services engineering percan cause premature aging of the skin, spective, a plant is something between or wrinkles. UVA rays are also responsa sun collector and an air-conditioning ible for sun allergies. They can indirectly unit that also happens to cast shadows. damage the DNA (genetic makeup) of Construction engineers ask about their the skin cells and increase the risk of weight. Architects use them for greening skin cancer. surplus areas. However, for landscape • UVB rays (5%, 280–320 nm) are rich architects, a plant is the most crucial in energy and are more aggressive than design medium and construction materPeter Petschek UVA rays. They only penetrate the epiial. This also includes the shadows they dermis, but cause the most dangerous sunburns. They can cast. Shadows are part of an extraordinarily multi-faceted directly damage DNA and overtax the skin’s own repair mechphenomenon. In his book, The Secret of Shadows, scientist Roberto Casati wanders deftly from astronomy and archi- anism. UVB rays greatly increase the risk of skin cancer. tecture to painting and mathematics, and on to philosophy • UVC rays (< 280 nm) do not reach the earth’s surface, beand physics, and impressively describes "the fascinating ca- cause they are absorbed by the ozone layer (Krebsliga Schweiz).

The sun’s radiant energy is vital for many processes on the reer of a mysterious phenomenon." (Casati 2001) Although, unfortunately, Casati does not write about the shadows cast Earth: the water cycle and other cycles, the growth of flora and by plants, his book is nevertheless highly recommended be- fauna. Depending on geographic location and radiation levels, cause it can unveil the complex quality of shadows to the light can be very damaging to human health. The problem of the thinning ozone layer increased public awareness of the interested reader.

As far as designing shadow-casting constructions in land- chemical thermal effects of solar radiation. Surplus chloroscape architecture is concerned, plants and their relationship fluorocarbons (CFCs) released by people into the atmosphere to light are certainly of fundamental interest. We will go into has damaged the ozone layer, allowing more UV rays to reach more detail about this phenomenon after examining the defini- the Earth’s surface, which increases the risk of skin damage and skin cancer. On the other hand, the physical effects of tions of light and shadow. light are also vital to people—for instance, for the sensory impressions recorded by the eye, in which light and color play Light the most important role. A sunny, autumn landscape is inspir— The sun is the star at the center of our planetary solar system. ing, but limited visibility and lack of contrast can also be dull The distance between the earth and the sun is approximately and depressing.

150 million kilometers. The earth receives an uninterrupted Shadows flow of energy from the sun in the form of radiation. Only a — fragment of this transmitted energy arrives on the earth’s surface; the rest is reflected by clouds, back out into space, Shadows can create a space or a projection. A shadow will or absorbed by gas molecules in the atmosphere. The rad- form behind an object if it is located in front of a light source. iation that reaches the earth’s surface is called global The object will also cast a shadow onto another surface if the radiation. It consists of both direct and scattered rays. Scat- front of the object is lit with a point light source, such as the tered radiation, which is also called skylight, is bounced sun or a spotlight. The sharply focused shadow shape cast around by clouds, water, and dust particles before reach- by an object is called a silhouette. The unlit portion of the object, which is in shadow, is called the eigenshadow. The ing the earth’s surface.

The vernacular term "light" refers only to the part of the deepest shadow, or umbra, is the darkest area of the shadow sun’s radiation that is visible to the human eye. Solar radiation because the light source is completely covered by the shadowconsists of electromagnetic rays of varying wavelengths. They casting object. The penumbra is the area in shadow that is only obscured in part from the light source, meaning that the are measured in nanometers (nm) and are composed of: • 50% visible light (400–780 nm), which provides light and light source is partially recognizable from the penumbra perspective. In this area of the shadow, a part of the light that color, • 44% infrared rays (>780 nm), which warms the skin and is obscured from the object is reflected on the surface. Real light sources are not point light sources; they possess a cermuscles, and • 6% ultraviolet (UV) rays (100–400 nm), which are neither tain spatial expanse, which is why the contour of the shadow is blurred. visible nor can they be directly felt.

Shadows play an important role regarding plants. Two ecological plant groups can be identified, based on the type of UV Rays available natural light: shade-tolerant plants and sun-tolerant — Ultraviolet rays have shorter wavelengths than visible light and plants. Species that can grow in very heavily shaded areas, infrared rays. This makes them more powerful and more able to such as beech, wild garlic, and yellow archangel are called shade-tolerant plants. Sun-tolerant plants are those that need damage skin and eyes. There are three types of UV rays: • UVA rays (95%, 320–400 nm) brown the surface of the skin. almost constant sun, such as thyme or stonecrop.

They penetrate deep into the layers of the skin, can even reach

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1 1. Umbra (deep shadow), 2. Silhouette (outline shadow), 3. Penumbra, 4. Eigenshadow, 5. Shadow line, 6. Shadow area (Casati, 2001).

2 1. Roots take in water.

2. The plant releases oxygen through the stomata.

3. Glucose is transported from the leaf to other parts of the plant. 4. Carbon dioxide enters the leaf through the stomata. 5. Water evaporates on the leaf via photosynthesis.

6. Chlorophyll in the leaf absorbs energy from the red, orange, blue, and violet parts of transmitted light, and reflects only the green light, which is why the leaves appear green. 7. Solar radiation: 50% visible light, 44% infrared rays, 6% ultraviolet rays (Burnie, 2008).

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3 The reproduced image of the light source becomes increasingly sharper as the opening in a barrier located between a diffuse light source and the projection surface becomes smaller. (Schlichting 1995) 4 Correct digital tree shadow (www.laubwerk.com) 5 Long shadows in an autumn mountain landscape 6 Dappled sun on asphalt

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Plants â&#x20AC;&#x201D; Shadow

Constructive Design of Small Buildings

Design challenges rarely follow a linear Structural planning involves fulfilling the process; rather, they are revealed while required bearing capacity and usability following a complex pathway of right or of a built structure for a specific length wrong decisions. In order to keep control of time. These also have to meet the cost of the design process in this Durcheinanefficiency and esthetic requirements. dertal (Valley of confusion) (Medici Mall, Structural design is the construction 1998), the authors of this essay wrote a stuof built structures. It includes the builddent handbook for the course Constructive ing process as well as the result, that is, Design in the Department of Landscape the structural sum of the individual comArchitecture at the Technical University ponents in the finished building. in Rapperswil. Small Buildings, shadeStructural designs are subdivided acproviding structures such as pavilions cording to components (foundation, wall Handbook or pergolas, are among the most basic construction, roof construction), accorddesign challenges for landscape archiing to material (wood, masonry, steel, reFabienne Kienast Weber tects. This essay sets out to systematiinforced steel), according to the assemPeter Petschek cally explain the procedure. bly of the components (solid structure, Any methodical practice requires a certain level of stringency. system building, frame construction) and according to building This is not always a simple matter in a creative process. It creates phase (earth work, shell construction, interior work). a basis from which the right questions can be posed and also Design methodology is the theory of the methods that are serves as a source of ideas for designers. Moreover, stringency generally applied when constructing a building. It systematizes is not a replacement for intuition or creativity; on the contrary, and abstracts the process of building. Design methodology can it leaves space for any design possibility and does not exclude be used to divide the total task into smaller parts, thus making ideas or options for known or universal solutions. The solutions it possible to develop situation-specific partial solutions. found during the design process can still be verified and questioned. It helps keep the design process transparent, accessible, Approaching and quantifiable. This method facilitates dialog, which is espeConstructive Design cially crucial for collaborations involving several team members — or professionals from other fields of expertise, because it pro- In order to discuss the basic design methods, we will first examvides an accessible and understandable work process. ine the design strategies implemented by architects.

The original role of the architect as universal genius is changIn Entwerfen – 25 Architekten 25 Standpunkte (Designing — ing into one of generalist. Architects are the heads of construc- 25 architects 25 points of view) (Lorenz 2004), Peter Lorenz tion projects, and are hence required to be familiar with all the interviews architects on the subject of designing. The results different areas of knowledge and expertise. They are advised verified that designing is a highly complex process that evolves and supported by specialists and specialist planners. from a process of discussions involving several people. The first Landscape architecture has also changed over time, from design step might be a simple sketch to solidify an idea. The designing gardens or clearly delineated spaces to the larger path to the finished project is developed from a process of intelprojects and future-oriented development planning common lectual effort and collecting information, verifying and evaluattoday. The spaces such architects usually work with have ing the analysis, and finally, further developing the original idea. not only expanded; the requirements involving public space Designing is creative chaos and needs a system of methodolhave become much more complex and diverse. Landscape ogy. "Sensuality is the goal, but rationality is the means," is Max architectural concepts are in demand today, but so also are Dudler’s answer to the question of whether he designs spontasolutions for small buildings. These include bus stations, pe- neously and emotionally, or systematically and rationally. destrian shelters, kiosks, pavilions, pergolas, and other shadeA comparable situation can be found in machine technology. providing structures that landscape architects and construc- If we look at a building within a landscape context as a technical tion engineers plan and realize in collaboration. The different system consisting of several subsystems, there are some obvifunctions and the often-complex conditions set by the client ous parallels in the VDI-Richtlinie 2222 "Konstruktionsmethodik take teamwork to arrive at appropriate solutions. For this – Konzipieren technischer Produkte" (VDI guideline 2222: VDI reason, interdisciplinary cooperation with architects, spatial Manual of Product Engineering and Design) published by the planners, and construction engineers is an absolute necessity, Association of German Engineers. Producing and using conin order to meet the challenges and requirements successfully. struction manuals calls for the following procedure: developBoundaries between the different areas of responsibilities often ing the idea, designing, and realizing. In general, this involves cross—thought processes interconnect, which creates an over- dividing the task into smaller parts and searching for as many lapping of ideas that ultimately leads to an overall solution. efficient partial solutions as possible, which when combined provide different variations on a concept. The first step is planDefinitions ning: the task is chosen, information gathered, and the devel— opment contract secured. The next design phase is to define Structural engineering and knowledge of structural theory and de- the tasks and establish a list of requirements. In the subsesign methodologies are basic requirements for structural design. quent design phase, a design to scale is created, which is then

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2. Analysis optimized and adjusted. In contrast to architecture or land— scape architecture, machine technology focuses on the choice The analysis examines the context and the project. It provides of material, production, assembly, and ergonomics. data about the existing local conditions, and important factors and information concerning the task that has to be developed.

Summary This offers an overview of the task. The first design ideas can — Formally developing a project is a dynamic process in which a be developed at this stage. spatial form evolves step by step, a process shaped by interactions, progress, and setbacks caused either by new knowlAnalysis — Context edge or by the client changing the requirements. These might In this phase, the site and object come into the dialog. The site involve economic aspects or additional requests that have to will not only change in form, but will also experience a converbe integrated into the design along the way. sion or new use. Time, and how it will actually be used, will Form, function, and the properties of materials and con- determine to what degree the new object has been integrated structions can be explained in a rational manner. Every form into the built, public, and social environment. This, however, can be measured precisely, and material properties can be does not imply that an attractive design solution is a guarverified according to physics. However, describing the ratio anteed upgrade for the site, or that it will be accepted by the between two dimensions, dealing with the existence or per- user. Designing is not merely a task of creating esthetically spective of the site, and explaining how a project relates to its attractive design solutions; it is also a task of satisfying specicontext, or how it is interpreted within its context, are all far fied requirements, such as functionality, financial viability, or more complex and difficult to articulate. Here is where per- dealing with its continued existence. sonal experience and individual ideas regarding architecture The following is a description of the most important points enter into the design process. The physical experience of the of analysis, without creating a hierarchy. Every task and every built space influences the individual’s perception. site will establish the importance of these points in a new way.

Constructive design is a synthesis of rational knowledge and emotional thinking. Contradictions and tensions that arise Site during the design process are not signs of failure, but rather Visiting the site provides an overview of the area to be conindicate progress. structed, an understanding of it as a whole. It is important to The design strategy Konstruktives Entwerfen in der Land- register the spatial and visual boundaries, the path structure schaftsarchitektur (Constructive design in landscape architec- or traffic patterns, and the infrastructure of the site in question. ture), which can be downloaded as a poster from the construct- Sketching is a good way of recording and analyzing the site ingshadows.hsr.ch website, identifies and defines six work precisely. Drawing reduces a spatial situation, whether it is a phases: task, analysis, concept, design, development, project. town square or a landscape, to its most essential characterThese phases guide the designer through the design process, istics. Accentuating or omitting individual elements transmits from the task to the project. This strategy is illustrated on the one’s individual perception of the site onto paper. Parameters poster: Content is a part of each work phase. It lists the factors such as size, proportions, and spatial and atmospheric effect that have to be taken into consideration. The result shows the are taken in subjectively and expressed by means of the drawoutcome of the relative status of the project. Theory provides ing. Through subconscious abstraction, a picture of the site more information on the subject by means of additional litera- is created that is the first critical and analytical approach to ture. The image book provides a view of the expected status the design.

Human-body dimensions can be used to measure the diof the development via plans, sketches, and photographs. The Konstruktives Entwerfen in der Landschaftsarchitektur manual mensions of the space. It is possible to measure the length of presents all the relevant factors of a design process and ex- a path, the width of a support, or estimate the height of a tree using span (the distance between the thumb and the tip of the plains their rational, underlying principles. small finger), fathom (the length of the outstretched arms of the human body), or stride (the distance between the instep of 1. Task both feet while walking).

— In addition to measurable site properties, there are charA construction or design process begins by formulating the problem and defining the tasks. Requirements presented by acteristics that cannot be tangibly articulated in dimensions. the clients serve as a helpful guide for the design to get started This is how the genius loci pervades the atmosphere. It is influin the right direction. The needs and requests can differ greatly enced by people and how they use the site.

Observing and recording the environment is a core subject from one target group to another. For older people, wheelchair accessibility is crucial, which means project requirements will area for landscape architects; the space around us is their field include minimum width for doorways or barrier-free entrances. of work and research. One must be able to observe very closely A list of requirements is a checklist for planners, allowing to recognize the finer points in the environment that can serve them to repeatedly assess feasibility and financial viability. It as design ideas, such as the fall of shadows, the branches of a can be adjusted according to need. As far as the client is con- tree, or other natural processes. cerned, the specifications are of interest because they might reveal any possible risks in his or her own plan.

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Schattenkonstruktion vor Ort

Constructive Design

Dozent P. Petsche

The use of analytical and subjective methods allows us to develop a concept out of these initial design elements.

Analytical Methods

Literature research can provide built examples. Gathering information about built structures and construction systems using different materials will supply an initial impression of the various design possibilities.

Analytical natural systems (bionics) offer the following design approaches: the branches of trees, for instance, are structural systems. Studying human limbs can give insight into the way supports and posts may be joined. There is a wealth of natural systems and processes that can be incorporated into architectural works.

The morphological box is another analytical, rational method used to aid design development. It breaks the task down into individual sections. For every partial problem, there are partial solutions, which, when combined in various ways, create a total solution. This does not mean that every solution is sensible or possible. Formulating the problem, the requirement specifications, and the analysis from the product and context will help the designer to evaluate and select the appropriate solution.

Subjective Methods

Teamwork and dialog are subjective or intuitional methods.

The tasks are discussed between two or more members of the team. It is also invaluable to exchange ideas with other professionals, such as construction engineers, other architects, carpenters, or steelworkers at an early stage. This allows the construction engineer to demonstrate possible variations of the structural system, for instance.

A similar procedural method is the iterative process, which consists of a sequence of sketches. This is a more complex process, because it deals with intuitive processes and is very broad-based. The designs do not build on one another consecutively; each one is individual and different.

The iterative process involves developing a concept, editing it down to the most specific points, and pursuing these in a coherent and thorough manner. The resulting concept serves as a foundation for further development and finally the actual implementation of the project. The project is visualized in non-scale sketches as a ground plan, sectional diagram, or perspective drawing.

can achieve this while making it possible to create a much finer construction: the supports almost float atop the slender posts. Horizontal wooden surfaces require a slight slope in order to avoid moisture build up and the damage it causes.

If the design calls for plants to be trained on the construction, the intervals and alignment of tension wires or lamellae have to be considered in order to make sure the plants will have the desired effect as they grow over time. If two different materials are to be combined, it is imperative to examine whether they are mutually compatible and how they can be joined together structurally.

The choice of supporting framework system depends on the load the structure will have to bear. Measures have to be taken to guarantee stability, such as braces to protect the structure against strong winds. Physical and mechanical properties like stability, elasticity, or tensile and compressive strength influence the form and choice of material and of supporting structure. In combination, they lend the project the desired atmospheric effect of lightness, liveliness, transparency, enclosure, or a monumental presence.

Because structural engineering is only marginally addressed at the bachelor level in landscape architecture, we recommend the book Structure Systems by Heino Engel (Engel 2007) as an initial way to choose a supporting structure, used in close collaboration with structural engineers at the educational and practice level. In Rapperswil, for instance, students are required to discuss their landscape architectural constructions with the structural engineer lecturers, before they take their projects to the next stage. They are also required to make a final seminar presentation about their project.

Form and Structure

Simple forms are created by joining points and lines that form surfaces and bodies. Some elementary geometric forms are the circle, the square, and the equilateral triangle. The most important aspects of these shapes are their absolute regularity and geometric precision. Symmetry and order also create a powerful effect. These primary forms represent a central concept to which all others are subordinated.

Circular buildings are not oriented; they are centered around their own midpoint. They express individuality and are confident in relation to the concept. The plaza or square is a cosmopolitan symbol. The four equal sides give the surface an omnidirectional effect, and, as with the circle, can be integrated freely into an existing context. Equilateral triangles 4. Design are created by dividing the square through its symmetrical â&#x20AC;&#x201D; axis, corner to corner. The forms of triangles and squares are The concept has now been developed. The next step is to more directly related. The rectangle has two long sides of equal precisely define and assess the design as regards material and length that can serve to orient a structure in space and can supporting framework, form, and design, and the layout and place emphasis on specific sides. function of the project.

More complex forms can be created by adding, subtracting, or repeating these basic forms. Criteria such as symmetry (dividing forms), proportion (the relationship between forms Material and Supporting Framework The appropriate material and supporting framework must be and proportions), and organization (the structure of forms) found in order for the concept to be realized. For example, define the design composition of the elementary forms.

In contrast to basic forms and combined forms, free forms large span widths in wooden constructions are only feasible with supports and posts that have large cross-sections, which do not follow design principles such as symmetry, propormake the structure look very robust. Steel, on the other hand, tion, or structure, nor are they based on geometric principles.

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Mikado Pergola

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Constructive Design

Shadeproviding Tents

mal surfaces with characteristics that Lightweight canvas tents have been imcorrespond to the structural requireportant shade-providing structures for ments of modern tents can be created centuries. They offer protection in hot easily within any perimeter. Minimal climates against the searing sun and surfaces represent the smallest posare fundamental to the nomadic way of sible surface within a given perimeter. life. Classic nomad tents are still used They are normally curved in a saddleon the steppes of central Asia and in the shape, and the curvatures in both main desert regions of the Arab world. They directions are equal in size and are are constructed from local materials On the Design and Construction of exact mirror images (negative Gaussian according to traditional methods, and Lightweight Canvas Structures curvature). Optimal stress distributheir lightweight and simple installation can be achieved because the tention mean they are easy to move around.

Siegfried Gass sion on each point in each direction of Black goat hair is woven using simple handlooms to form strips of fabric fifty to seventy centimeters the surface is equal in degree 4. A multitude of possible tent wide. The strips are sewn together and the fabric is attached forms can be created using these characteristics, the classito wooden posts hammered into the earth, forming the roof cal forms of which will be presented in the following typology. and side walls of the tent. The dark roof sections of canvas absorb the rays of the sun and create dense shade.

Tent Typology Mobility, simplicity of installation, light weight, and local — materials are the fundamental design requirements for the The Anticlastic Curved Four-point Surface roof of a handmade tent in the desert or on the steppes.

— Urban civilization in Mediterranean societies has also de- The four-point tent is the easiest tent form to derive from the pended heavily on fabric awnings over the centuries. In Spain, basic, anticlastic curved minimal surface. The membrane retractable canopies called toldos 1 that are mounted above spans two opposite-positioned high and low points. Frei Otto the street between the eaves of houses have become an im- built this archetypal form of modern tent construction in 1955 portant part of standard construction. In other countries, the in collaboration with Peter Stromeyer as a music pavilion for canopy cloth is hung freely above the streets. The charac- the garden show in Kassel. 5 teristic way that the cloth hangs is defined by the weight of By varying the positions of the high and low points, diverse the material, which is not stable in the wind, but flutters and spatial configurations can be created that are either more billows, subjecting corner details and attachment points to open or more closed, depending on the different intended very dynamic loads. uses of the tent construction.

The knowledge of the form, construction, layout, and If the membrane surface is constructed from single secmaterials used for all of these traditional canvas shade con- tions of canvas, the way that they are positioned plays a destructions has been—similar to the classical tent construc- finitive role in the material’s formal design and load-bearing tions of the nineteenth century—passed on from one master capability. Positioning the sections parallel to both main tent builder to another down through the centuries. directions will inevitably lead to the formation of ridges between both high points and both low points, even if there is Shade-providing Tents and no seam at the connecting lines. In these ridges, which are the Principle of Minimal Surface a clear deviation from the minimal surface, a concentration — of load will develop that can lead to overstress. On the other Tent construction in the twentieth century, including modern hand, the fibers, and therefore the load-bearing elements of shade-providing tents, convertible/retractable roofs, and the membrane, are positioned so as to optimally carry the sunshades, is founded on physical and engineering principles applied loads. Turning the direction of the canvas sections that underpin of the design, construction, layout, and choice forty-five degrees avoids a direct continuation of fibers; then of material. the form can easily adjust to that of the minimal surface.

The key principle of modern tent construction, particularly However, there is little curvature in the fibers (similar to the as demonstrated through the research and projects of Frei hyperbolic paraboloid), with the result that the form can beOtto 2, is a double curved surface that conveys the load as come very distorted even in cases of relatively small loads. pure tensile force from different directions to the points of sup- This leads directly to the idea of turning the axis of the secport—which means that very lightweight, pliant constructions tions of fabric 22.5 degrees in relation to the main direction can be used. These surfaces also have a highly complex geo- (or grain) of the fabric. metric form that shares cer3 A very clear description of the 4 See Institute for Lightweight tain aspects with the hyper- 1 See Institute for Lightweight Structures (ed.): IL 30 – Velas, Toldos, mathematical foundations of Structures (ed.): IL 18 – Seifenblasen, bolic paraboloid, but unlike Sonnenzelte, Stuttgart 1984, p. 93 ff. minimal areas can be found in: Stuttgart 1987, p. 74 ff.

Stefan Hildebrandt, Anthony Tromba: these, cannot be described 2 Winfried Nerdinger (ed.): Frei Otto Panoptimum: mathematische 5 Winfried Nerdinger (2005), p. 179 f. mathematically 3.

– Das Gesamtwerk, leicht bauen, Grundmuster des Vollkommenen, In experiments with soap natürlich gestalten, Basel, Boston, Heidelberg 1987. film, anticlastic curved mini- Berlin 2005.

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1 Nomad tent in the steppe region of Saudi Arabia

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2 Toldos in Córdoba, Spain 3 Shade-providing fabric roofs in Istanbul, Turkey 4 Pavilion of the Federal Republic of Germany at EXPO ’67 in Montréal, Canada.

Architects: Frei Otto and Rolf Gutbrod 5 Load transfer of the anti-clastic curved minimal surface 6 Minimal surface as soap film 7 Four-point surface: Music pavilion at the Federal Garden Show in Kassel, Germany, 1955.

Architect: Frei Otto.

Realization: L. Strohmeyer & Co. 8 Different spanning possibilities of the four-point surface 9 Cutting patterns of the four-point surface

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Shade-providing Tents

Tents with Support in the Surface â&#x20AC;&#x201D; A support in the surface is necessary to achieve the required spatial curvature in large tents, as is the case with the applied loads transfer. In contrast to rigid constructions, this cannot be done by means of a point support of the surface, because Canvas surfaces with numerous spanning points If additional spanning points at the edge are necessary to the span is too small to achieve sufficient spatial curvature. span a surface, the surface curvature can only be modeled This was illustrated by the attempt to support a soap bubble optimally if the surface is not too strongly differentiated or if using a moistened needle. Large spatial deformations, and high and low points alternate at the edge, meaning an even therefore effective surface supports, can be achieved if the number of spanning points. An uneven number of edge points, load is transferred via a linear element from the surface to the as well as peaks that extend far from the surface, will not point, or via a planar element. lead to all areas of the tent having the appropriate threedimensional curvature.

Ridge Tent A point-symmetrical arrangement of spanning points will The effect of a linear element, called a ridge or flute, in a minigive a surface a horizontal center. This leads to water accumu- mal surface can be explained by means of soap film experilating from rain or snow; the water collects in the middle and ments. The consistently level, minimal surface between three can no longer drain off the low points. A continuous drainage points is spatially deformed by a second minimal surface. The of water can be guaranteed by tilting the plane of reference or newly created form can be modified by adding a ridge in its by making an opening in the middle of the tent. sag, meaning that the surface can be modeled by means of a linear element, and the applied loads are transferred from the surface through the linear element to the support points.

Wave Tent A wave tent is suitable for very long, rectangular roof struc- In contrast to an unsupported surface, the spatial curve of tures, for example for shaded pathways, which have an or- the surface sections is greatly reduced; because the ridge is dered alternating of high and low points at the edge. Placing relatively stiff, the deformation of the entire surface subject the low and high points opposite one another creates a dy- to load is also greatly reduced. Integrating more ridges will namic form with very good three-dimensional curvature of the increase the rigidity of the tent. The curve radius is smallest membrane: all of the high points can lie on one horizontal at the support points and increases continuously as it reaches level and the low points on a another, without the surface the mid-span. The form of the ridge is defined by the preload; forming horizontal surfaces. This will solve the problem of in extreme cases (preload â&#x2020;&#x2019; â&#x2C6;&#x17E;), the ridges are rectilinear and the surface sections are flat triangular surfaces. water accumulation.

The classic form of the rotationally symmetrical, pointed tent is a clear illustration of the construction principle "from A Mast without Guy Lines This is a special tent form in which the horizontal component the surface via the line to the point." of the tensioning forces is introduced into the foundation by the end elements of the sail, rather than by a separate sail.

Umbrella as an Inverse Ridge Tent This arrangement is stable if the base of the mast is positioned Funnel-shaped umbrellas with the lowest point at the center behind the forward-lying lateral tension points. The mast is for controlled drainage of precipitation can be understood as positioned on the masthead in the tangent plane between the inverse (or inverted) ridge tents, whereas with smaller umperipheral cables: it moves according to the load in question, brellas, having several layers of fabric in the seam can provide and can adjust to a new static equilibrium. the effect of a ridge. In the case of larger umbrellas, in a manThe membrane lies on the mast and undergoes consid- ner similar to ridge tents, a strap (girth) or cables sewn into erable mechanical stress due to movement caused by load casings (or pockets) can be used.6 shifts. A curved mast is a possible solution here, but it will be subject to eccentric curvature. The loss of the functional Ridge Tent as Crossed Wave advantage of guy wires or lines, which reach into the space but An alternating, concentric arrangement of ridges and flutes are not disruptive, is offset by a soft construction that displays under the tent surface, supported in the center by a mast, creconsiderably more deformation as a result of wind pressure ates a space similar to a cross vault. This introverted spatial and snow load. impression can be enhanced by guiding the membrane down to the ridge cables along the side masts.

Several four-point surfaces can be combined to cover larger areas. This method will convey a serial-type quality, whether the surfaces are similar or not. Combining different types of canvas will open up even more freedom of design.

6 See the project "Solar Umbrellas," p. 210.

Essays

60

20 Soap film model of the star wave of the Tanzbrunnens at the Federal Garden Show in Cologne, Germany, in 1957.

Architect: Frei Otto

20

21

21 Soap film model of a wave tent, with parallel ridges between high and low points 22 Soap film model of the Institute for Lightweight Structures. Architect: Frei Otto

22

23

23 Roof of the market square in Phoenix, Arizona, U.S.A. Architect: R. Larry Medlin 24 Soap film model of an arch-supported tent for the roof of the sports center in Kuwait, 1974. Architects: Frei Otto and Kenzo Tange 25 Soap film horizontally spanned, with full-surface support

24

25

26 Festival tent for the inauguration of the first North Sea pipeline, at Aberdeen, Scotland, in 1975.

Architects: Frei Otto with Ove Arup & Partners 27 Convertible roof over the monastery in Bad Hersfeld, Germany, in 1968, opening and closing. Architect: Frei Otto

26

27

28 Soap film in catenoid form between two rings of different sizes 29 Design model for a cooling tower in minimal surface form with flexible edges. Architect: Frei Otto

28

63

29

Shade-providing Tents

Certain material properties, in particular the strain curve properties, must be taken into account for the cut patterns and in compensating for a change in length when under load; biaxial tension tests and long-term tests are indispensible to attaining the highest level of precision. Because of the deformation of the individual fibers in the weaving process, uncoated fabric displays great flexibility in the warp direction (with the grain) — the original highly curved fibers are pulled straight — but in general less flexibility in the fill direction (across the grain of the fabric), and in some cases a shortening of the fabric has even been reported: the initially straight fill fibers are curved by the warp fibers. The opposite is true for coated fabric, due to the additional mechanical stress in the warp direction, i.e. along the grain.

PTFE-coated Fiberglass Fabric

This relatively expensive material is suitable for use in extreme climatic conditions, in making membranes with large span widths, or when a particularly long lifespan is required.

Because the inflammable polytetrafluoroethylene (Teflon®) coating is highly dirt resistant and UV radiation resistant, it shows few signs of aging. The material has a light transmission level of up to thirteen percent. The relatively stiff material requires very high pre-stressing forces. Its low buckling resistance makes it unsuitable for convertible constructions. The individual sections of fabric, which require a special cut, are joined by high frequency welding.

PTFE Fabric

The open, uncoated polytetrafluoroethylene fabric’s excellent buckling properties and perpendicularity make it suitable for Cotton/Polyester Blend Fabric This uncoated and therefore porous fabric is suitable for light- complex, convertible, shade-providing structures where a weight shade-providing tents that can only be erected in warm long lifespan is required. However, the structural properties of seasons. It has a high level of flexibility that allows the use the material mean this fabric is only suitable for constructions of parallel sections of fabric without cutting. Both fibers are with relatively small spans. It is flammable and, depending on mixed in the yarn, but cotton, which is a renewable resource material and thickness, has a light transmission level of up to and the traditional material used in tent construction, will thirty-seven percent. It has exceptional antifouling properties become shorter and expand if exposed to moisture: the tent and a lifespan of over twenty-five years if treated and handled will stretch and the pores between the fill and warp fibers with care, as is required by all open fabrics. Problems arise will close. Polyester fibers have a high level of tensile strength, in regard to its resistance to driving rain, which can be solved meaning this relatively lightweight material is still sufficiently by sealing the gaps in the fabric with a fluoropolymer coatstable under load. Unprotected fibers have a lifespan of five ing. The seams are stitched, as is the standard procedure with to ten years, depending on levels of strain and care. The open fabrics. normally flammable, open fabric is known for having a lighttransmission level of approximately ten percent, as well as ETFE Film for its foldability and buckling resistance. This makes it also a In contrast to anisotropic fabrics, highly translucent ethylene good choice for convertible or mobile constructions. The sec- tetrafluoroethylene film has an isotropic stress-strain curve. tions of fabric are joined and the membrane edges produced It is also has very good mechanical properties, is flame resisusing the same sewing techniques that are used with all un- tant, and, typically for fluoropolymer bonds, highly resistant coated fabrics. to chemical and biological stresses, as well as UV rays. The standard 250-micrometer-thick film has a low tear resistance, which limits the span of weight-bearing constructions, and PVC-coated Polyester Fabric This mass-produced membrane material remains a very popu- is the reason why the material is mainly used in the form of lar choice, due to the clearly differentiable material proper- pneumatic cushions. As with all membranes made from fluoties and relatively low cost. The polyester fibers ensure a high ropolymer bonds, ETFE film’s lifespan of twenty-five to thirty level of tear resistance, and the polyvinyl chloride coating years is very high. It also offers a level of light transmission protects against ultraviolet (UV) rays and moisture. An addi- much higher than glass, which is an important consideration tional surface coating (PVDF varnish) provides protection that if the design calls for covering natural habitats. The individual keeps the coating from becoming prematurely brittle or soiled, sections — up to 1.55 meters wide — are joined by welding. resulting in a lifespan of twenty years or more. The fabric is classified into five different standard type classes according to minimum tensile strength, and is highly flammable. It has a light transmission level of four percent. Compared to open fabric, the coating reduces the level of flexibility, normally required by differentiated cut sections of fabric. The standard joining technique employed is high frequency welding. A strap is sewn to the edges as additional reinforcement.

Essays

64

30 Double-sided linen fabric

30

31

32

33

34

35

31 Cotton/polyester blend fabric: Tent in front of the Academy in Nürtingen, Germany in 2007.

Architect: Siegfried Gass 32 PVC-coated polyester fabric: renovation of the star wave tent above the Tanzbrunnen in Cologne, Germany, in 2000.

Architects: Frei Otto, SL-Rasch 33 PTFE-coated fiberglass fabric: tent in front of a ministry in Riyadh, Saudi Arabia, in 1995.

Architect: SL-Rasch 34 PTFE-fabric: solar umbrella in Jeddah, Saudi Arabia, in 1987.

Architects: Bodo Rasch and Associates 35 ETFE-film: summer shade tent in a private garden in Leonberg, Germany in 1987.

Architects: Frei Otto, Jürgen Bradatsch

Standard membrane materials and their properties

Fabric type Surface weight [g/m²] Tear resistance warp / weft [N/5cm] Translucency UV-resistance Life expectancy Standard color

Use

65

Cotton / blend fabric uncoated 350 to 500

PVC-coated Polyester fabric coated 590 to 1500

PTFE-coated glassfiber weave coated 800 to 1500

PTFE fabric

ETFE film

uncoated 300 to 750

film 87.5 to 350

1700/1000 to 2500/2000 up to 25 % satisfactory

3000/3000 to 9800/8300 0 to 25 % good

3500/3500 to 7500/6500 0 to 15 % very good

400/2200 to 4500/4500 15 to 40 % very good

5 to maximum 10 years white, can be painted almost any color light, temporary, and foldable membrane; small span widths; rainproof

15 to 20 years

more than 25 years

more than 25 years

50/50 to 60/60 up to 95 % very good, without UV transmission more than 25 years

white, other colors available on demand standard material, highly versatile, limited foldability, rainproof

white, limited colors available on demand high quality standard material, technically demanding, cannot be folded, rainproof

white, other colors available on demand superior quality standard material, specifically for convertible roofs, semi-rainproof

transparent, other colors available on demand high quality standard material, specifically for pneumatically supported membranes, rainproof

Shade-providing Tents

Overview Plants Twiners Actinidia 76

Akebia 78

Aristolochia 80

Berchemia 82

Celastrus 86

Fallopia 92

Humulus 96

Jasminum officinale 99

Jasminum polyanthum 99

Jasminum sambac 99

Lonicera 100

Schisandra 110

Thunbergia 111

Wisteria 114

Plants

72

Clinging rootlets Campsis 84

Creepers Ficus 93

Hedera 94

Hydrangea 97

Parthenocissus 102

Clematis 87

Parthenocissus inserta 103

Passiflora 104

Vitis 112

Jasminum grandiflorum 98

Jasminum mesnyi 98

Jasminum nudiflorum 98

Rosa 106

Tendrils Ampelopsis 79

Scrambling climbers Bougainvillea 83

73

Overview

Botanical name Common name Family

Actinidia Actinidia Actinidiaceae

Growth

The actinidia genus comprises approximately 40 species that are indigenous to China, Eastern Siberia, Japan, and Java. They are twiners, rather fast growing shrubs, and are cultivated for their tasty fruit, which is very high in vitamin C. They have very dense leaf growth and are resistant to illness. Many species are dioecious; but bisexual species are also available.

Bot. name Eng. name

Actinidia arguta Hardy kiwi

Actinidia callosa Mini Kiwi, Chinese gooseberry

Climbing form

twiners

twiners

Growth

up to 3 m/y 10‒15 m tall, 5‒6 m wide

up to 2 m/y 8‒10 m tall, 4‒5 m wide

Location





Soil

humus-rich soil

humus-rich soil

Hardiness

to -20° C

to -5° C

Leaf

large leaves up to 13 cm long, oval

large leaves up to 12 cm long, cuneiform

Blossom

white; May-June; lightly scented, mostly hidden by dense foliage, dioecious

large, white; May; lightly scented, mostly hidden by dense foliage

Fruit

edible, somewhat less flavorful than real kiwis

edible, green, red overflowing and mottled

Choose for

UQu

UQu

Care

prune in winter

prune in winter

Special notes

Young plants need to be protected Young plants need to be protected in the event of a hard winter. in the event of a hard winter.

Variety: 'Issai': self-fertilizing clone; 'Meander Female': large fruit yield

Actinidia deliciosa

Plants

76

Actinidia coriacea Chinese egg gooseberry

Actinidia deliciosa (A. chinensis) Kiwi

Actinidia kolomikta Chinese gooseberry

Actinidia polygama Silver vine

twiners

twiners

twiners

twiners

up to 2 m/y up to 8 m tall, up to 4 m wide

up to 3 m/y 8‒10 m tall, 6‒8 m wide

up to 1.5 m/y 3‒6 m tall, 3‒5 m wide

up to 1.5 m/y 3‒6 m tall, 3‒5 m wide





humus-rich soil

humus-rich soil

humus-rich soil, calcareous soil

humus-rich soil, calcareous soil

to -5° C

to -20° C

to -20° C

to -20° C

often semi-evergreen, large leaves up to 13 cm long, oval

large leaves up to 20 cm long, cordate

large leaves up to 15 cm long, oval; male leaves are creamy white and pink or reddish on top

large leaves up to 15 cm long, oval; male leaves are creamy white on top

red with yellow anthers; June; mostly hidden in the dense foliage

many flowers, white to creamcolored; May to June; fragrant, dioecious

small, white; June; slightly fragrant, mostly hidden by dense foliage

small, white; June; slightly fragrant, mostly hidden by dense foliage

edible, brown, juicy

edible, reddish brown, fuzzy skin

edible, yellowish green, approx. 2.5 cm long

edible, yellowish green, approx. 2.5 cm long

UQu

UQu

UQu

U

prune in winter

prune in winter

prune in winter

prune in winter

Winter protection is needed for young plants in the event of a harsh winter. Also goes (erroneously) by the name of A. henryi: but A. henryi is a different plant.

Winter protection is needed for young plants in the event of a harsh winter.

Variety: 'Jenny': self-fertilizing hermaphrodite, 'Bruno': female bears very large fruit

Winter protection is needed for young plants in the event of a harsh winter.

The distinctive color of the leaves appears after 2 or 3 years.

Winter protection is needed for young plants in the event of a harsh winter.

The distinctive color of the leaves appears after 2 or 3 years.

77

Act

Botanical name Common name Family

Hedera Ivy Araliaceae

Growth

Hedera helix

Plants

Evergreen, develops climbing adhesive pads in its juvenile phase. The genus comprises approximately 16 species that are distributed throughout the northern hemisphere with the exception of North America. The appearance of ivy's young phase and mature phase differs greatly. The mature shoots flower and bear fruit, while only the young shoots form adhesive climbing pads. All varieties of ivy tolerate full shade.

Ivy can cause great damage to buildings if it does not receive the appropriate care or is provided with the wrong climbing aids. It can tear the plaster from a facade when it becomes too heavy. It is also necessary to be careful with cracks or splits, which the plants can infiltrate without being noticed.

Bot. name Eng. name

Hedera canariensis Canaries ivy

Hedera colchica Persian ivy

Climbing form

clinging rootlets

clinging rootlets

Growth

up to 3 m/y 5‒7 m tall, 5‒6 m wide

up to 2 m/y 10‒20 m tall, up to 10 m wide

Location





Soil

humus-rich, moist, and nutrient-rich soil

humus-rich, moist, and nutrient-rich soil

Hardiness

to -5° C

to -15° C

Leaf

evergreen, young leaves trilobal, 10–15 cm long, yellowish-green, bronze in winter, adult shoots ovate to round, dark green; petiole dark red

evergreen, very large elliptical, rarely lobed, 10–25 cm long, dark green

Blossom

appear only on adult shoots, panicles, greenish; September–October

only on adult shoots, round umbels, greenish; September–October; nectar and pollen source for bees

Fruit

round, black, ripe in winter, up to 1 cm across

round, bluish-black, ripe in spring, up to 1 cm across

Choose for

Qe

Qe

Care

prune in late spring to maintain desired size; pruning not necessary

prune in late spring to maintain desired size; pruning not necessary

Special notes

Variety: 'Gloire de Marengo': foliage green with silvery-gray areas between the veins, irregular cream-colored border

Variety: 'Dentata Variegata': foliage undivided, light green with irregular gray-green spots and creamcolored edge 'Sulphur Heart': leaf center irregularly variegated large, yellow

94

Hedera helix Common ivy, English ivy

Hedera helix 'Glacier' Common ivy, English ivy

Hedera helix 'Goldheart' Common ivy, English ivy

Hedera helix 'Plattensee' Common ivy, English ivy

Hedera hibernica Atlantic ivy, Irish ivy

clinging rootlets

clinging rootlets

clinging rootlets

clinging rootlets

clinging rootlets

up to 2 m/y 10‒25 m tall, 4‒10 m wide

up to 0.5 m/y 5‒8 m tall, 3‒4 m wide

up to 0.5 m/y 5‒8 m tall, 3‒4 m wide

up to 2 m/y 10‒15 m tall, 4‒8 m wide

up to 2 m/y 10‒20 m tall, 4‒10 m wide











humus-rich, moist, and nutrient-rich soil

humus-rich, moist, and nutrient-rich soil

humus-rich, moist, and nutrient-rich soil

humus-rich, moist, and nutrient-rich soil

humus-rich, moist, and nutrient-rich soil

to -20° C

to -10° C

to -20° C

to -20° C

to -15° C

evergreen, very variable, mostly trilobal, dark green with lighter lamina; mature form unlobed, cordate form, tapered long, shiny dark green; turns mottled brownish-violet when exposed to summer sun

evergreen, shoots green-violet, leaves are tri- or pentalobal, to 6 cm long, gray-green with narrow white border

evergreen, shoots first deep pink, then brown; leaves trilobal, up to 6 cm long, dark green with irregular pale yellow spots in the center

evergreen, small tri- or pentalobal, 4–6 cm long, fresh green with silvery white veins, in winter dark green; when exposed to sun in winter become mottled brown-violet

evergreen, pentalobal, central lobes longer than side lobes, leaves larger than H. helix, 8–15 cm long, matte green with pale gray veins, petiole violet-green

only on mature shoots, round umbels, greenish; September–October; plants are floral mature in 8–10 years, nectar and pollen source for bees

only on mature shoots, round umbels, greenish; September–October; plants are floral mature in 8–10 years, nectar and pollen source for bees

only on mature shoots, round umbels, greenish; September–October; plants are floral mature in 8–10 years, nectar and pollen source for bees

only on mature shoots, round umbels, greenish; September–October; plants are floral mature in 8–10 years, nectar and pollen source for bees

only on mature shoots, round umbels, greenish; September– October; nectar and pollen source for bees

round, bluish black, ripe in spring, up to 1 cm across

round, bluish black, ripe in spring, up to 1 cm across

round, bluish black, ripe in spring, up to 1 cm across

round, bluish black, ripe in spring, up to 1 cm across

round, bluish black, ripe in spring, up to 1 cm across

Qe

Qe

Qe

Qe

Qe

prune in late spring to maintain desired size; pruning not necessary

prune in late spring to maintain desired size; pruning not necessary

prune in late spring to maintain desired size; pruning not necessary

prune in late spring to maintain desired size; pruning not necessary

prune in late spring to maintain desired size; pruning not necessary

Variety: 'Sagittifolia': leaves spear-shaped, very slender, 5–7 cm long, pentalobal, dark green; in winter reddish-brown; moderate growth up to 4 m high

Variety: 'Woerneri': very similar, but leaves somewhat larger

Mature form

95

Hed

Overview Projects Pergolas ALCOA Forecast Garden 122

Pergola am Wassergarten 126

Dan Kiley Pergolas 128

Shade Roof 130

Acapulco Pergolas 134

CSS Tribschenstadt 136

Sunshade on the Riva 140

Jacaranda Square 144

Trellis 148

Projects

118

Pavilions Follies 154

Strand Jetty Shade Structure 156

Pier 45 160

Pavilion in Spreebogen Park 164

Pavilion Botanical Garden 168

The Birdhide 172

Orquideorama 176

Water Flowers Pavilions 182

Pavilions Parc des Rives 186

[C]SPACE 190

The Serpentine Gallery Pavilion '09 Houtan Park 198 192

"Shadow Forest" 202

119

Overview

CSS Tribschenstadt Lucerne, Switzerland 2005 freiraumarchitektur gmbh

â&#x2020;&#x2018; View of the pergola from the office building â&#x2020;&#x2019; View under the pergola to the hanging cables with a sufficiently large plant trough

Projects

The freestanding pergola is located at the center of the inner courtyard of a new complex of buildings in the Tribschenstadt in Luzern. Its triangular ground plan refers to the surrounding buildings. The 34-meter-long, 15-meter-wide pergola is made of 100% galvanized steel, trained with various climbing plants, and has a clearance height of 3.90 meters. It is constructed using round supports 15 centimeters in diameter, beams made from T-profile steel supports, and lateral rung-like supports of the same profile. The supports are spaced at double-rung intervals along the beams. The spacing changes to an interval of one-rung from beam to beam.

This staggered spacing enables the outward-facing end supports to be placed directly under the beams that run diagonally at this point. The rung level was augmented by means of Inox cable pulls (www.jakob.ch) that run transverse to the metal supports and serves as climbing aids. The four-millimeter-thick steel cables are laced through holes drilled into the rungs. The posts are fixed to the ground by welded flanges, which are bolted into the concrete base with compound anchors. This joint is below the surface of the pavement and covered with a water barrier to prevent moisture entering the concrete body. On the upper ends of the supports there are double link plates to which the beams are bolted. The drilled holes for the screws are elongated lengthwise, so as to compensate for any possible deformation of the material when erecting the construction. The rungs are bolted directly onto the beams. The climbing plants grow in steel plant troughs, which are embedded halfway into the earth under the pergola. The hanging cables extend from these troughs to the level of the rungs. The plants are distributed along the rung level and the horizontal cables spanned at this point.

The cable winches are attached at ground level by a frame construction made from band steel that is concealed in the troughs. A variety of climbing plants were used to green the structure; these include wisteria, clematis, akebia quinata, campsis radicans, lonicera japonica, parthenocissus quinquefolia, and vitis riparia.

The dense growth along the hanging cables creates the effect of spatial partition and protection.

Assigned to them are seven concrete benches.

An additional concrete element is a 2.40-meter-high wall plate that cuts across the construction in the tapering area of the pergola, creating a spatial conclusion. There are five hanging lamps arranged in a row to illuminate the space. The required electricity is supplied by a cable that is fed through the supports and follows along the beams.

136

Top view

S 1:150

1 2

1 Concrete wall plate 2 Hanging cables, frame: band steel 8 mm, cable: INOX ø 4 mm 3 INOX-cable ø 4 mm, grouted external thread, intermediate, bolted onto the long side additionally with molded water resistant connector, spacing between the cables: 600 or 300 mm 4 Tubular steel supports, 152.4 X 7.1 mm, length 4140 mm, attached to a concrete lid 5 Secondary supports T-Profile 100/100/11 6 Primary supports 1/2 I PE 300

3

4

5

6

137

Pergolas

Sectional view a-a

S 1:100 1 Detail of support beams 2 Hanging cables, frame: band steel 8 mm, cable: INOX ø 4 mm 3 Primary support, 1/2 I PE 300 4 Secondary support, T-Profile, 100/100/11 5 INOX cable ø 4 mm 6 Tubular steel supports, 152.4 /71 mm, length 4140 mm 7 Detail of attachment to ground

1 3 4 5 2

6

7

Sectional view b-b

Projects

S 1:100

138

Details

S 1:10 1 2 3 4 5 6 7 8

1 2

3

4 5

6 7

T-iron, 100/100/11 INOX cable ø 4 mm Grouted intermediate thread Grouted external thread M10 ½ I PE 300 M12 Tubular steel, 152.4 X 7.1 X 4140 mm 9 FLA 15 10 Water barrier EP 5 GA 11 4 anchoring dowels, M16, L = 165 mm, bolted directly into the concrete ceiling, covered with the water barrier EP5 GA and 1/2 I PE 300 M12

8

9 10 9 11

Details

139

Inox cables as climbing aids

Pergolas

Orquideorama Medellin, Colombia 2006 Plan:B Arquitectos + JPRCR Arquitectos

Projects

The "Orquideorama" can be found in the Botanical Garden in Medellin, Colombia. The construction design has an overall size of 4,200 square meters and a maximum height of 16.7 meters. It was built in 2006.

The shade thrown by the tree-like roof guarantees a stable climate of 16 to 28 degrees Celsius and creates the climate needed for the sensitive orchid plants to grow and thrive.

In the jungle, the tall trees assume the function of providing shade. In the Orquideorama, a hive-like, hexagonal metal structure, paneled with pinewood lamellae, deflects any direct sun rays from reaching the lower levels.

Rainwater is collected in large polyester pans, then led to the ground through a system of pipes and ultimately used to irrigate the plants.

The Orquideorama consists of several "trees." The hexagonal basic form of the individual elements is continued at the floor level. The geometric form and the possibility of constructing the roof as needed means that the system can be expanded whenever there is a need.

176

Sectional view of a "tree"

S 1:100 1 Skylight (metal frame) with transparent polycarbonate panels 2 Steel construction for the skylight 3 Metal roof parapet 4 Roof gutters 5 Transparent polycarbonate panels 6 Steel construction for the inclined roof 7 Downspout pipe

8 Steel supports 9 Pressure-treated Patula pinewood cladding 10 Cross section of steel supports 11 Tubular steel, anchored to the main frame 12 Steel construction for the wood paneling 13 Modular system for orchid exhibition 14 25.4 cm tubular steel supports 15 Concrete pile foundation

1

2

3 4 5 6 7 8 9 10

11

12

13 7 14 15

177

Pavilions

CAD rendering, structural assembly

Initial design sketches

Projects

178

Isometric drawing

Plan

Sectional view

179

S 1:1000

S 1:500

Pavilions

Houtan Park Pudong, Shanghai, China Expo 2010 Kongjian Yu ‒ Turenscape

Living organisms have the ability to adapt, change, and protect themselves. Houtan Park at the Shanghai 2010 Expo is designed as a living organism. Located on a former "brown lands" field on the Huangpu waterfront, Houtan Park is a showcase for the Expo as a regenerative public green space.

At the very north end of the linear park, a shadow-casting structure is located. It is an advanced version of the Dujiangyan plaza’s Golden Canopy. This shadow-casting structure spreads out in the manner of tree canopies surrounding a water pond, the same pond which collects the water that has been cleaned through the wetland system. It is a celebration of water that has been heavily polluted and then been cleaned through the landscape as a living system.

The shadow-casting canopies are painted in shades of pink, the color tones of lotus flower petals, a metaphor for the lotus that has its roots in dirty mud but produces a plant and flowers that are clean and elegant. The shadow-casting canopies are made of metal, while the supporting poles are made of steel and painted white.

→ The shade-providing construction in Houtan Park was further developed from the Turenscape project "Golden Roof" at Dujiangyan Plaza in Dujiangyan.

Unlike the Houtan project, in Dujiangyan the steel net hangs on bronze rods.

Projects

198

Plan

Top view

S 1:1000

S 1:50 1 Steel poles, finished surface in white 2 Steel bar network, finished surface in pink

1

2

Projects

200

Sectional view

S 1:50 1 145 X 45 mm bamboo pavement (5 mm joint).

2 50 X 50 mm wood beam and H 20 mm wood block base per 0.5 m 3 Retaining wall made of local natural stone 4 30 mm granite, deep gray 5 Reinforced concrete

1 2 3 4 5

Detail view of the connection between the pipe and the net

S 1:5 1 2 3 4

Iron disk, 20 X 3 mm 2 half steel rings, 20 X 3 mm Steel pole Steel bar network

1 2 3 4

201

Pavilions