UAE PAVILION EXPO DUBAI 2020 CONSTRUCTION AND SUSTAINABILITY DESIGN STUDIO
TURN WASTE INTO SPACE
2017 / 2018
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PROJECT DESCRIPTION AND CONCEPTUAL DESIGN
Pavilion Location in Expo 2020 Accessibility from the main Entrance
[Introduction] On November 27, 2013 the Bureau International des Expositions general assembly in Paris awarded Dubai as the host of an upcoming Universal Exposition in 2020. The site of the expo was chosen to be located on the South-Western end of Dubai, next to the Sheikh Mohammed Bin Zayed road – one of the main throughways leading to Abu Dhabi, and some 1,5 kilometers North from the Al Maktoum International Airport. The masterplan 4
for the exhibition shows a centrally located plaza and several alleys radiation from it, along which all the numerous countries, that decided to participate in the exhibition, will express and showcase their understanding of the official 2020 Expo’s theme – Connecting minds. Creating the future.
[Theme] The above-mentioned theme in its polysemy gives many possibilities of understanding its meaning in one’s unique way. After the long research into the history, current development and problems of the United Arab Emirates both in its cultural and socio-economic aspects we focused on a subjects that is problematic not only in the country itself but also around the whole world – the recycling of waste. Today estimated world’s population is 7.6 billion, by 2050 it most likely will rise up to 10 billion. Not only there will be more of us but also we are predicted to be more and more wealthy which will lead to even more significant mass consumption. The more we buy the more waste we
generate. Already today, every American produces up to 2.1 kilograms of waste every day. Even though people were mastering recycling for decades now, making it more and more popular and making it possible to recycle more and more materials, there are still things that are not widely recycled even though it is possible. Those things are in the spotlight of our interest – the unused mobile phones and food waste. We believe that there is a possibility of enhancing the use of recycled materials in the architectural design in order to make it more sustainable and hence we propose the motto of the United Arab Emirates pavilion to be Turning waste into space.
FIRST CONCEPTUAL MODEL
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[Design Objective] The main objective was to design a medium-sized plot temporary pavilion serving primarily as an exhibition space as well as learning and gastronomic facilities. The pavilion had to be designed in accordance to plot and design parameters and the sustainability controls as stated in the Expo’s masterplan. In addition to that we decided that its design, both in its structural aspect and the appearance, has to reflect and represent the Turning waste into space theme. [Initial Design Concepts] The first challenge of the design process was developing a common language for the visual and architectural representation of the problem of recycling mobile phones and food waste. As the two components have barely anything in common but the recyclability, it seemed reasonable for us to use materials retrieved from them in the process of recycling and which can also be easily recycled after the Expo. In terms of shape of the pavilion we decided it should have more or less an organic form. Another important issue was the accessibility. It was clear for us that all the spaces open to visitors must have an easy access for the elderly and disabled, hence the initial idea of making a one-storey structure but soon it was clear that due to the site parameters and guidelines the area of such pavilion would not be sufficient to accommodate all the functions. The idea of a system of ramps going through the whole pavilion, providing an easy access to all the spaces, emerged soon after. In terms of structure the initial idea included carbon fibre skeleton but due to its insufficiently determined properties as well as relatively high cost we were forced to find an alternative, the most suitable turning out to be steel. 6
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VISUAL ANGLE
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[The proposal] The pavilion is a two-storey structure consisting of three connected and structurally dependent parts – the passage, the piazza and the main building. The circulation is linear to optimize the organization of people flow and build up the spatial narrative. Visitors enter the pavilion through a ramp shaded by chitin panels. This is also the place where the exhibition starts. They move up to the first floor where they can overlook a piazza downstairs and the main exhibition room behind the glazed wall in front of them. Then they enter the exhibition room by the door on the right-hand side. The exposition in the main room focuses on the problems connected to overuse of mobile phones and the low awareness of this issue. It is meant educate and encourages visitors to recycle their old or no longer used mobile phones. They later leave the room by the door on the opposite side and go down to the piazza. Here they can rest, take a drink in the bar, attend events in the auditorium underneath the exhibition room or just leave the pavilion onto the pedestrian path to continue their journey around the expo site. The pavilion has a slightly rounded C letter shape. The main part housing the exhibition room and the auditorium is oriented towards southern edge of the plot in order to maximize the area and the performance of the solar panels. The structure is entirely made of prefabricated steel elements joined together in situ and then cladded. The passage is shaded for the visitor’s wellbeing until the piazza. A 3D printed chitin which is a natural food waste product is used. It composes the shells of crustaceans and varies in density and strength according to where on the animal’s body it is. It’s a bio-degradable, environment-friendly 3D printing material that could eventually replace plastics. 8
MAIN ZONES DIGRAM
It can be chemically stabilized by various agents and submerged in water without any degradation. Visitors will encounter along the entrance some digital semi - transparent panels that showcase the process of recycling the wasted shells. Then there’s a piazza which as an open-air space is devoid of shading system giving the visitors a feeling of being both inside the pavilion but outside the shading structure, it is a break not only for a rest but a symbolic division between two other parts of the pavilion. Arriv-
ing to the main exhibition room, the main destination of the visitors, the materials used for the enclosure of this space are incorporated into a thermal sandwich system composed of 3 layers, which are respectively from outer to inner: 1. PVC coated polyester, a flexible fabric membrane that is capable of reducing radiant heat gain, keeping interior temperatures cooler during warmer weather conditions, which has a thermal conductivity of 0.14W/ mK. It was chosen because it is a
fabric that is totally recyclable, therefore ideal for the temporality of the pavilion. Moreover, PVC is proven as a material with minimal environmental load in terms of CO2 emission when compared with metal or glass products of the same application. 2. The second layer is the insulated fireproof layer with a thermal conductivity of 0.035 W/mK. 3. The inner layer is a silicone coated glass used to provide a smooth lining for the interior, with a thermal conductivity of 0.2 W/mK. This overall insulated triple layers system has a U value of 0.18. The steel structure resembles an endoskeleton or an armour of a non-specified crustacean and can be easily dismantled after the Expo and rebuilt or reused elsewhere. Concerning the Solar panels, the silicon photovoltaic cells are applied on the areas facing the direct sun on the outer shell, while some elevated solar panels installations are also implemented in the landscape for increasing the energy production. Furthermore, our aim is also to achieve a sustainability goal by recycling these photovoltaic cells once they are disassembled after the Expo and in a way once again by that exhibiting the recycling phenomenon in the pavilion. It is expected that by 2030 a cumulative PV panel waste of 1.7-8 million tons will be produced, which could be recovered to produce a total of 60 million new panels.
SCHEMATIC PLAN
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BUILDING STRUCTURE
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BUILDING STRUCTURE
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Structure elements: Steel Connections: Bolts As mentioned, the main aim behind choosing all the materials is the same as our theme, sustainability and recycling. We made the formation of the pavilion from steel members in different sections according to the loads which been carried by each part, also all the connections is bolts to be able to be reused again after the expo of Dubai. The structure components is formed to serve the designed form of the pavilion which build according to the conceptual design of the main spine: from the top; arches, trusses slap, main beams, and columns which carry the loads to the ground.
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6 LOAD TRANSITION THROUGH STRUCTURE ELEMENTS
horizontal load of the wind. 2. The trusses slap load in addition to the arches loads to be transfered to the main I beams which carry the loads of the arches and finishing materials, the dead loads and live loads on the trusses slap. 3. The columns in the bottom (5) takes the whole load to the ground [Step 01] which require a bigger section to be able to transfer the load safely to the The graph is describing the load tran- ground. sition through the structure elemtnes from the top to the ground; [Step 02] 1. The main arches which contains; from main frame (1) and sub struc- In this step, we choose the sections ture (2) to make it more stable to car- of each structure element according ry the vertical load (its own load and to two main conditions; the first is the the finishing materials) as well as the design principles, and the second is 12
the loads which carried by each element. We choose the square section for the main arch to make it easier in the connections through metal plates, otherwise, we choose the I beam with different sections from the whole structure which is shown in details in the following graph.
CLARIFYING THE LOADS ON THE MODEL
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Y [Section 01]
x t
h
x
Element: Main Arch Material: Steel Section: Hollow Square
h Y Dimensions h t 80 5.0
Weight
Area
11.70
14.9
Axis X-X & Y-Y I S r 139 34.7 3.05
Surface Area Um Ut 30.9 26.42
J 217
b c
[Section 02]
s
X
c
X
h
Element: Sub Structure (arch) Material: Steel Section: I Beam
h-2c
r1
t
weight
Sec. No Kg/m 100 8.10
Area
Aweb
cm2 10.3
cm2 3.36
h mm 100
b mm 55
Dimensions s t r1 mm mm mm 4.1 5.7 7
c mm 12.7
Y
Axis X-X Axis Y-Y h-2c Ix Sx rx Iy Sy ry mm cm4 cm3 cm cm4 cm3 cm 74.6 171 34 4.07 15.9 5.79 1.24
b c
[Section 03]
s
X
c
X
h
Element: Trusses Slap Material: Steel Section: I Beams
h-2c
r1
t
weight
Sec. No Kg/m 160 15.8 14
Area
Aweb
cm2 20.1
cm2 7.26
h mm 160
b mm 82
Dimensions s t r1 mm mm mm 5 7.4 9
c mm 16.4
Y
Axis X-X Axis Y-Y h-2c Ix Sx rx Iy Sy ry mm cm4 cm3 cm cm4 cm3 cm 127 869 109 6.58 68.3 16.7 1.84
b c
[Section 04]
s
X
c
X
h
Element: Main Beams Material: Steel Section: I Beams
h-2c
r1
t
weight
Sec. No Kg/m 330 49.1
Area
Aweb
cm2 62.6
cm2 23
h mm 330
b mm 160
Dimensions s t r1 mm mm mm 7.5 11.5 18
c mm 29.5
Y
Axis X-X Axis Y-Y h-2c Ix Sx rx Iy Sy ry mm cm4 cm3 cm cm4 cm3 cm 271 11770 173 13.7 788 98.5 3.55
[Step 03] Calculations of the loads of the whole building and compared with the maximum load which could be carried by the main member to be sure that it’s safe. Using the following formula, we calculate the total load which carried by each member + its own load, then we get it / m2, and divide it with the maximum load which could be carried with this section / m2 to check if it is safe or not. We considered the load of each element to be sure that it will be totaly safe.
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BUILDING ENERGY 1. 2. 3. 4.
CLIMATE ANALYSIS OF DUBAI ARCHITECTURAL DESIGN MATERIALS SELECTION TECHNICAL SYSTEMS
1 [Parametric studies] Climate analysis for the city of Dubai. Weather data for Dubai (25.14° N 55.17 °E) Summary of mean daily values of the main parameters.
TABLE 1: MONTHLY WEATHER DATA FOR DUBAI
[Monthly diurnal average] The monthly variations of the outdoor dry-bulb temperature show that the annual cycle can be divided into 3 distinct periods : a 4 month period of mild weather (December to March inclusive) characterized by daily mean temperatures of 20- 23 C, a warm period (November and April) with mean temperatures of 25-26 C, and a hot period (May- October) with mean temperatures of 29-34 C.
HOURLY VALUES OF DIRECT AND DIFFUSE SOLAR RADIATION ON THE HORIZONTAL AND HOURLY MEAN, MAX AND MIN VALUES OF DRY-BULB TEMPERATURE FOR EACH MONTH PLOTTED AGAINST THE CALCULATED ADAPTIVE COMFORT RANGE. BACKGROUND COLOR IDENTIFIES MILD, WARM AND HOT PERIODS OF THE YEAR
The diurnal temperature range of 10-12K involves night-time ambient air temperatures that are low enough for convective cooling of building structures for most of the year. However, the useful cooling potential available from this source is being eroded by the urban warming caused resulting from the heat discharges from air conditioning appliances on buildings and motor cars.
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FIG 2: SUN PATH DIAGRAM FOR 24N WITH MILD, WARM AND HOT PERIODS OF THE YEAR MARKED. EFFECTIVE SHADING IS REQUIRED ON ALL ORIENTATIONS ALL YEAR ROUND
FIG 3: HOURLY DRY– BULB, WET– BULB AND SKY TEMPERATURES AT THE BEGINNING OF THE HOT PERIOD (MAY) AND SURFACE TEMPERATURE ON HORIZONTAL PLANE EXPOSED TO SUN IN DUBAI
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[Sun chart] Sunshine is strong throughout the year with an annual average of 8 hours of bright sunshine per day, rising to some 10 hours per day in the hot period. Clearly, solar protection of occupied spaces is essential outdoors as well as indoors throughout the year. The incident solar radiation is high all year varying in the range of 3.7- 7.0 kWh/m2 on unobstructed horizontal surfaces. Roofs, streets, pavements and other exposed manmade surfaces will get extremely hot affecting outdoor comfort as well as building cooling loads unless specially treated.
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[Sun shading chart] Sun shading is practically needed all the time Generally recommended to be used during summer and winter mornings.
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[Wind velocity range] Winds average 4.0-4.5 m/s throughout the year the strongest coming from the direction of the Gulf on most months except for the hottest months ( July- September) when the predominant direction is recorded as South.
[Illumination range] The sky luminance is high throughout the year in the range 15 000- 70 000 lx during workhours in the mild period to 50 000- 100 000 lx in the hot period about half is diffuse illuminance from the sky vault. Under these conditions, 1-2% of the outdoor illuminance is sufficient to meet required illuminations levels for any indoor activities. These fractions can be achieved in buildings with very modest areas of glazing. High glazed facades risk serious problems of glare as well as excessive cooling loads and overheating.
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[2- Architectural design: Day lighting analysis on the model] The model is located on the southern part of the site. Its closed part is facing the sun course. This enables the solar panels to operate efficiently.
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2 [Architectural design: building shape, envelope, daylighting] The main shape of the biggest zone in the pavilion is formed not only according to our conceptual design and its function, but also respecting the environmental aspects which concluded from the weather analysis of Dubai. It’s oriented to the south to be able to use this huge solar energy in producing electricity by placing the solar panels in the top of the form oriented to the south. This was considered also in the step of making the treatment of the material of coverage by making a sandwich of 3 layers; 2 layers of PVC polyester and isolation in between to diminish the U value of the whole surface. After we design considerations that mentioned, we used best energy to calculate the amount of energy that need for the cooling of that zone by following these steps: 1. Created a simplified form for our zone. 2. Created components of the different surfaces according to the layers of materials’ of each. 3. Definition of the proprieties of the zone; number of people, conditions inside, artificial lighting, ..etc 4. Run the simulation and get the results hourly to keep going with the energy consumption process. In a following step, we included the results of this part in comparing between the energy we need to power our zone and the energy we produce out of the solar system.
STEP (1) SIMPLIFIED FORM OF THE ZONE
STEP (2) THE MATERIALS’ INPUTS IN BEST ENERGY
STEP (3) DEFINITION OF THE PROPRIETIES OF THE ZONE
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3 [Materials seletion] THERMAL SANDWICH SYSTEM INCORPORATING THREE LAYERS in order to achieve a better U value
AVAILABLE INSULATION MATERIALS MAKE THE MEMBRANE ROOF AS AN OPAQUE ELEMENT
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4 [HVAC systems] Solar panels : For solar energy applications the prospects are extremely good for all types of applications both thermal and electric; sun-tracking appliances can intercept as much as 6.5-8.5 kWh per m2 collector area daily throughout the year.
150cm
150cm
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Solar panels Calculation of PVGIS solar electricity generation for 153 PV Cells.
Total primary energy demand:
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4 [HVAC systems] Cooling air - water system.
Input data
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4 [HVAC systems] Sizing of the equipments - People density for the thermal zone: Expositions: 0.2 persons/m² - Required air change ratio for the thermal zone: Expositions: 0.01 m³ /s per person - Total air change rate needed to ensure good air quality: 0.01 x 0.2 x 180 = 0.36 m³ /s - Latent and sensible cooling power due to air change: 0.36 x 1.2 x 52 = 22.46 kW - Total sensible heat to be treated with the air system: 6 kW - Air flow rate : Q= 1260 m³ /s - Size of the air ducts and the grilles in each thermal zone considering the max speed in the ducts Main ducts: 5 m/s Secondary ducts ( within thermal zones): 3m/s Grilles: 1.5 m/s - Size of the main ducts (supply and return) = 1260/ 5 = 0.25 m² (square of 50cm x 50cm) - Size of the secondary ducts (supply and return) - Grilles: 5 elements
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4 [HVAC systems] Direct evaporation cooling in the entrance area. Radiative and evaporative cooling techniques are complementary and are applicable in the warm and hot periods of the year helping to restore comfort.
CHITIN MATERIAL IS 3D PRINTED IN A SHAPE THAT IS DESIGNED AS EVAPORATION BRICKS, MOISTURIZED WITH THE DEW COLLECTED FROM THE SURFACE DURING THE NIGHT. IT LETS THE DRY HOT AIR TO BE NATURALLY COOLED DIWN BY THE ENERGY CHANGE
Currently, the temperature difference between the airconditioned spaces inside the buildings and the streets and urban spaces outside frequently rises above 20 degrees, high enough for a thermal shock when entering or exiting airconditioned buildings and motor cars. It is necessary to prevent that as much as possible, with adapting standards of thermal comfort and a better understanding of the technical aspects of building design for these climates
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[Conceptual Development of membrane structure] The use of material is inefficient in bending elements. The interior fibers never reach their maximum stress levels, while always maintaining weight. From this idea, the truss was developed where the inefficient material of the beam was turned into clear space and each truss carried specific tension and compression forces. However, the simplest efficient structural system is when load is carried by one element that is either completely in tension or compression. While in two-dimensions, this system is a cable for tension loads and an arch for compression loads, in three dimensional space, this system is a dome and tensioned fabric, respectively. This development is outlined in Figure 1. Therefore, terms "membrane structure" and "tensioned fabric structure" not only allude to the nature of the material used in such design, but also the way in which the forces act within the system. The stresses created are membrane stresses, that is, stresses acting parallel to the local surface and constant through the thickness of the surface. Unloaded, the surface prestresses are all in equilibrium. However, when the membrane is loaded, since it can not carry any out of plane stresses, it deforms until all the surface forces find a new equilibrium. Pretensioning of the membrane is necessary to decrease potential deflection. On a loaded pretensioned membrane, the final deflection will be less than a nontensioned membrane. However, at the same time, the final tension will be higher. The primary structure, which is usually made up of compression elements, play an important role for it equalizes and maintains forces from the prestressing of the fabric. Not only do they transmit the loads to the ground, but the supporting structure ultimately controls the geometric parameters.
THE CONCEPTUAL DEVELOPMENT AND EFFECTIVENESS OF TENSIONED MEMBRANE STRUCTURES (KOCH ET AL., 2004)
termines the long term appearance of the structure for it is the most visible Membrane structures, encompass- element of the structure. ing both the tensioned fabric and the supporting structure, can span from 3 Membrane Criteria: to 20 meters to spans more than 200 Mechanical properties: meters. For spans more than 200 me- The mechanical properties of most ters, the fabric is supported by cables importance to the designer are the with steel or air so that unsupported tensile strength, which measures the span of the fabric is actually less than force required to rupture the material, 30 meters. tear strength, which is the resistance to propagate an existing tear, and [Material Characteristics] elastic properties, such as stiffness, which is the relationship between the The selection of membrane material modulus of elasticity and the area of is important to the successful design the cross section of fibers. of the tensioned fabric structure. The material contributes to the structural Membrane fabric: function of the system, as well as oth- Polyvinylcholoride (PVC) coated er important properties involving du- polyester fabrics have been used and rability, insulation, light transmission tested since the 1960’s. The wide and fire protection. Also, the mem- use of this material is due to their low brane component of the structure de- cost, as well as their ease of handle. [Membrane type]
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However, their life expectancy is only 10-15 years and fire ratings can be improved. The PVC coated polyester has tensile strength from 350 MPa to 1,200 MPa and a strip tensile strength of 3,100 N/5cm to 5,800 N/5cm for membranes weighing 800 g/m2 to 1,100 g/m2 (Huntington, 2007). The pre stress levels of PVC coated polyester fabric range from 1-4 kN per meter (Shaeffer, 1996). The PVC coating helps the material to achieve high tear strength for the soft PVC chains around the fibers at the tear to resist further tearing. PVC also has moderate stiffness as well as moderate behavior to creep. [Design specifications] Load considerations: Wind loads are the main consideration for membrane structures. In order to resist these loads, the membrane must have sufficient tensioning and curvature. There are several loads that are negligible in membrane design. The selfweight of the membrane is usually negligible, but often included in the analysis. Moreover, due to the negligible weight of the membrane, seismic loads are also usually insignificant and not incorporated in the analysis. Rain loads are also rarely considered since water will be designed to shed rapidly to avoid ponding. Live roof loads can also be significantly reduced for it usually accounts for building material during construction, which is irrelevant in the case of membrane structures. Lastly, as of yet, temperature gradients of the membrane have not produced accountable loads for the fabric. Although there is no set safety factor for the strength of the selected fabric, conventional practice is to use a factor of 4 for short term load cases and a factor of 5 for live load cases (Huntington, 2004).
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[Insulated tensile fabric] In order to develop a tensile roof system that is capable of meeting the very high thermal values of an insulated conventional roof, while retaining the virtues of sculptural form and a clear structural span, a sandwich system can be placed with some technology to pattern and join panels that provides an extremely versatile approach to insulating membrane roofs. People have grown accustomed to tensile fabric being used for stadia and unheated venues, but actually the opportunity exists to employ a high performance membrane system as the external envelope for virtually any building. Being such a lightweight material, fabrics inherent limits of thermal performance severely restrict the applications to which it may be put. Actually the need to insulate buildings to a much higher standard has become unavoidable. The new thermal insulation regulations require a U Value of 0.25W/m2. To achieve this, it would be required to put in place a three membrane layers; an outer membrane identical to a normal tensile roof; an insulated membrane suspended beneath the outer layer; and a lighter weight inner lining giving the underside for the system a smooth appearance. The jointing and the connection of the thermal layer to the steel arch and the building perimeter were designed to form a continuous vapor barrier to condensation, always a potential headache in a thermally insulated roof space. Condensation forms on the inner surface of the outer membrane and drips down onto the outer surface of the thermal insulation. Channels at the roofs perimeter collect the drips and allow water to safely drain away to the outside. With currently available insulation materials an insulated membrane roof has one drawback; it is opaque. By overcoming the thermal limitations usually associated with
fabric, it becomes viable as a building material in areas previously off-limits to membrane construction. The widely acknowledged benefits of fabric can now be introduced into considerably more building types where lightweight construction has intrinsic advantages.
EXEMPLE OF THE USE OF THERMAL INSULATED FABRIC STRUCTURE IN A DEMOUNTABLE THEATRE AT THE MILLENNIUM EXHIBITION SITE IN LONDON IFAI EXPO 2000