the
design of
Burj Al
Arab hotel
by Tom Wright,
Design Director
What was the brief for the hotel? The client asked us to design a building that would become a symbol for Dubai. Sidney has it's Opera House and New York has the Statue of Liberty so Dubai would also have a building that people would associate with the place. What makes a building symbolic? We looked at the other buildings in the world that are symbols to see what they had in common. We found that they were all totally unique in shape and they all have a simple easily recognisable form. We decided that the test to determine if a building is symbolic is if you can draw it in 5 seconds and every one recognises it. Why did you make the hotel look like a giant sail? Dubai is becoming a world resort location so the building had to say holiday, fun and sophistication all things associated with yachting. This mixed with Dubai's nautical heritage it seemed an appropriate shape. Why is the hotel out to sea? It helps its uniqueness. It looks like a sail / boat. If it was on shore it would block the sun on the beach in the middle of the day. Does the hotel stand on rock? The building is built on sand, which is unusual as most tall building are founded on rock. The building is supported on 250 1.5M diameter columns that go 45 meters under the sea. As there is only sand to hold the building up the columns rely on friction. Are there any unusual materials used in the building? The screen that encloses the third side of the atrium is made of 1mm thick glass fibre fabric with a Teflon coat to stop the dirt sticking. The screen is the largest of it's type and covers an area of one and a half football pitch and is hung from the top of the building by over a kilometre of 52mm cable. Other amazing facts... The diagonal trusses on the side of the building are as long as a football pitch and weigh as much as 20 double-decker busses. They were built 15 KM from the site and brought by road to Dubai on huge 80 wheel lorries which had to be specially imported from South Africa. The highest truss took a day to lift into place. If one man was to build the building himself it would take about 8,000 years to finish.
Technical by
Details
fabric David
atrium
wall Dexter
The solution to overcome the complex 3-dimensional shape of the hotel atrium wall whilst maintaining the overall sail-like form of the building was to provide a series of shaped membrane panels that could be pattered to the defined geometry. The membrane is constructed from 2 skins of PTFE coated fibreglass separated by an air gap of approximately 500mm and pre-tensioned over a series of trussed arches. These arches span up to 50 metres between the outer bedroom wings of the hotel which frame the atrium, and are aligned with the vertical geometry of the building. The double-curved membrane panels so formed are able to take positive wind pressures by spanning from truss to truss and negative wind pressures by spanning sideways. Additional cables have been provided running on the surface of the fabric to reduce the deflection of the membrane. The trussed arches which can extend out from the supports by up to 13 metres are supported vertically at the 18th and 26th floors by a series of 52mm diameter crossbraced macaloy bars. Girders at these floors transfer the load to the core structure. These bars are then pre-tensioned to ensure that the whole structure remains in tension. An expansion joint is provided for the full height of the building on the right hand side of the wall. This enables the building to 'breath' under wind loads and avoids the exertion of large horizontal loads on the relatively weak bedroom structures. The resulting form is entirely appropriate for the building and its function with the fabric reducing solar gain into the atrium and providing an effective diffused light quality. It is also appropriate for the Middle-East region where its predicted lifespan and selfcleansing qualities should resist the aggressive environment.
The Burj al Arab (or Arabian Tower) hotel is built in the shape of a modern yacht sail to reflect Dubai′s seafaring heritage combined with a modern aspect moving forwards into the future. It accommodates 202 one, two and three bedroom suites.
The Burj is 321 metres high and is the tallest stand-alone hotel structure in the
world. The Burj is built 290 metres off the Dubai coast on a triangular, man made, landscaped island with sides of 150 m in length built off the sea bed in 7.5 metres of open sea.
The gross area of the Burj al Arab is 1.2 million square feet with 28 double height space floors, each floor is 7m high.
A gently curving road bridge links the island (which is some 450m offshore) to the Dubai mainland.
The island is protected by special hollow concrete armour units. These present a perforated sloping surface to the sea that absorbs the waves without throwing water onto the island.
The concrete structure, with exposed diagonal steel wind bracing, is triangular in plan founded on 250 concrete piles which penetrate the sea floor to a depth of more than 40 m.
The accommodation wings enclose two sides of a huge triangular atrium that runs up the full height of the accommodation floors. The third side, facing the shore, is enclosed by a double skinned, Teflon coated woven glass fibre screen; the first time such technology has been used vertically in this form or to this extent.
Dicroyic lights illuminating the exterior of the hotel in varying colours throughout the night.
The atrium is the tallest in the world at 182 metres high.
Site mapLog inWebsite terms of useWebsite built by Net-ConceptionOther The hotel rests on an artificial island constructed 280 metres offthe Dubai shore and 450m to its furthest point. To make the foundation secure, its builders drove 230 40 metre long concrete piles into the sand. The foundation is held in place by the friction of the sand and the silt along the length of the piles. The surface of the island was created using large rocks which were circled with a concrete ‘honey-comb′ pattern armour which serves to
protect
the
foundations
from
erosion.
Of the hotel's total five year construction period, it took 3 years to complete the island. The following stages were involved in the island construction process:
Temporary tube piles driven into sea bed
Temporary sheet piles and tie rods driven into sea bed to support boundary rocks (see figure 1)
Permanent boundary rock bunds deposited either side of sheet piles
Hydraulic fill layers deposited between bunds to displace sea water and form island (see figure 2 with fill layers partially complete)
Permanent concrete armour units placed around island to protect it from the
waves 2m diameter 43m deep piles driven through island and sea bed below to stabilize structure (see figure 3)
Island interior excavated and temporary sheet pile coffer dam inserted
2m thick concrete plug slab laid at base of island
Reinforced concrete retaining wall built
Basement floors created (see figure 4)
For the last eight years, since the completion of the Burj Al Arab, Tom Wright has continued to work with the Atkins team designing projects for some of the most prestigious international clients. The current portfolio includes work throughout Australasia, the Far East, the Middle East, Europe and the USA. The Atkins design office will consider all types of projects in the built environment, a selection of recent projects can be seen on the Atkins Design website by following this link: www.atkinsdesign.com
Site mapLog inWebsite terms of useWebsite built by Net-ConceptionOther Tom Wright Architect RIBA (formerly Tom Wills-Wright)
.
Tom Wright is the architect and designer of the Burj al Arab in Dubai, UAE. The Burj Al Arab (Tower of the Arabs) was conceived in October 1993 and completed on site in 1999. The lower left image shows Tom Wright′s first drawing of the Burj al Arab concept that was shown to the client in October 1993 which along with the simple card model shown above convinced the client that the tower should be built. The felt pen illustration to the left was an early development sketch of the hotel drawn by Wright on a paper serviette whilst he sat on the terrace of the Chicago Beach hotel which stood adjacent to the site of the Burj al Arab. The brief to the architect was to create an icon for Dubai, a building that would become synonymous with the place, as Sydney has its opera house and Paris the Eiffel Tower
so Dubai was to have the Burj al Arab. On the links page the Atkins Press pack can be downloaded which contains further information on the Burj al Arab. Tom Wright lived in Dubai during the design and construction of the project working as the project Design Director for Atkins one of the world′s leading multi discipline design consultancies. Since 1999 Tom Wright has continued to work for Atkins as Head of Architecture from the Atkins H.Q. in Epsom, London. Tom Wright is British, born in Croydon a suburb of London on 18th September 1957. Educated at the Royal Russell School and then Kingston Polytechnic school of Architecture. Wright became a member of the Royal institute of British Architects in 1983 and has been in practice ever since.
Free-D High Rises Dr. Karel Vollers Integration of digital technologies into the various stages of building development rapidly increases the variety of high-rise volumes. A scheme has now been developed to classify the various building shapes. As shaping largely follows the modeling tools that architects have available, this scheme is based on those tools as well. Consequently, no knowledge of mathematical formulae is required to describe the complex curved façades. Transforming a shape is simple, but the structural consequences are considerable.
Modeling Software and High-Rise Shaping Many non-orthogonal high-rises are designed to be iconic - to pinpoint urban projects, cities, regions, and even countries on the global map. Generally their façades are curved, or unusually shaped, for esthetic reasons, and sometimes to improve the building performance. Complexity of fabricating and constructing superstructures and façades, increases with the geometrical complexity. Remarkably, repetition of elements is losing importance. Various major projects demonstrate the economical feasibility of large-scale application of non-standard products. The relative ease by which one can now design, allows rapid shape development and quick generation of digital data on components and their production.
High-rise shaping is strongly related to the modeling tools that architects have available. Nonorthogonal building shapes traditionally are drawn by repeating floor surfaces upwards into a 3-D composition by applying the software commands Copy, Move and sometimes Rotate. Subsequently, façades are generated around the floors.
Figure 1a: The CAD-tool shape scheme.
Figure 1b: The CAD-tool shape scheme. As shown in Figure 1, standardized shape names have been developed by the author to describe the specific groups and variations of shapes. For instance, building volumes with upward repetition of floors, without scaling or rotation, are called Extruders. Variations on the basic orthogonal volume are introduced by inclining the line along which floors are moved upwards and by bending the line. As the floors are multiplied upwards, a rotation can be added, turning the volume into a twister. The basic twister has a constant rotation around a vertical axis. Thus all floors stay identical and façades on each floor are repeated. Though repetition generally is advantageous, often now the rotation is varied and the volumes additionally are tapered. Such varying adds identity - and indicates that repetition of elements loses importance. Non-standard elements get affordable, owing to digitizing of all stages of building development. Rotors are generated by rotating a line around an axis. When axis and line both are vertical, a Cylinder results. Free-shapers and Transformers are at the fore-front of recent building developments. Data processing for form generation, and subsequently production, in recent years is eased by scripting or adopting parametric modeling procedures. In such software, shapes are described by relations between their composing elements. Some programs instantly provide data, such as on floor surface changes when, during the design, a building volume is bent sideways. The shapes described in the system can all be generated by parametric modeling. Transformers are volumes that have been transformed either as a whole, or in part. Carvers are sculpted by deducting or adding parts that are described by intersections with other parts.
In an Angler, identical floors are stacked under a fixed angle. An angler can consist of straight segments leaning in different directions (Figure 2a). When the inclination angle varies, or when built of straight segments interconnected by bent segments, it is called a Slider. Sliders can overlap to achieve a more rigid structure, shorten traffic routes and provide alternative fire-escapes. One of the Figure 2b sliders for stability in a corner rests on another slider. This additionally enables elevator shafts to vertically continue. A Rotor is a building volume created by rotating a line around a vertical axis. When this line is a semicircle with its ends on the axis, a Globe results. Holes are carved in the globe of Figure 2c. Rotational building models can be varied easily by manipulating the curve that is rotated. The Figure 2d tower seems a rotor, but is a Transformer with elliptical floor plans. Such a volume can be drawn with solid modeling software by first stretching a globe upwards and then squeezing it horizontally over one axis. Such transforming turns it into a Scaled rotor.
Figure 2a: CCTV, Beijing (by OMA)
Figure 2b: Dancing Towers, Dubai (by Zaha Hadid)
Figure 2c: RAK Convention And Exhibition Centre Ras Al Khaimah, Dubai (by OMA)
Figure 2d: Torre Agbar, Barcelona (by Nouvel) A twister has twisted façades that repeat on all floor levels (Figure 3a). The twisting superstructure in the façade of the Figure 3b twister has wide columns with vertical sides. They repeat upward, shifted sideways and maintaining an overlap. The zone between outer structure and flat recessed glass façades provides sunshaded balconies. The inward fold of one façade gives the tower an orientation. As the number of façades around a twister grows, the shape resembles more a cylinder. This can allow for arranging a circle of vertical columns behind the façade. With vertical columns there is no torque on the structure. Tapering implies less vertical repetition, but this in Figure 3c and 3d twisters is compensated by horizontal repetition: 6 façades and 5 wings respectively.
Figure 3a: Turning Torso, Malmö (by Calatrava)
Figure 3b: Infinity Tower, Dubai (by SOM)
Figure 3c: Fordham Spire, Chicago (by Calatravea)
Figure 3d: Gazprom, Petersburg (by RMJM)
Figure 3e: Ocean Heights One Residential Tower, Dubai (by Aedes) A tordo is a transformed volume, with at least one corner moved out from the orthogonal structural grid. It thus has one or more twisted façades. The mullions of the Figure 3e tordo connect to parallel vertical structural walls. All components of the twisted façades are different. Freely curved glass panes have as yet not been produced on a scale fit for high-rise. Therefore, twisted surfaces were replaced by cylindrical surfaces or were tessellated (by approximating the curving shape with flat triangular panes). Just like the underside of a set of stairs, a twisted surface can be approximated by flat vertical and horizontal surfaces. Stepped twisters are built of stepped flat façades. The Figure 4a Stepped hybrid twister has stepped surfaces that connect around a cylinder. When floors are moved upwards and sideways, along a curving axis, a Slider results. By adding a rotation, it becomes a Sliding twister. When the 3D axis is a helix, the volume is named a Helical
twister. Helical twisters can adjoin, intersect or merge, depending on their positioning and proportions
(Figure 4b). Figure 4a: Mode Gakuen Spiral Tower, Nagoya (by Nikken Sekkei)
Figure 4b: Cobra Towers, Kuwait
Figure 4c: Dubai Towers, Dubai (by TVS) Overlapping can provide a vertical zone for elevator shafts. The Dubai Towers (Figure 4c) are Tapered sliding twisters. Their floor plans scale down, while moving upward and rotating along a double curved axis. This curvature of the axis is varying, and chosen such to result in pleasingly curved façade contours. The vertical structural cores stay within the octagonal floor plates. Where floors are very eccentric to the core, high atria are made to reduce structural loads. The increasing use of non-standard elements in twisted facades implies that such geometry is not applied for economic gain by repetition, but for ease of construction. While twisted façades are double curved, the straight floor ends and façade transoms are easier to measure and realize than curved elements would be. The repetition of lines on such shapes helps understanding the geometrical buildup. The inclining contours add a notion of movement to the shape - depending on the degree of rotation, torquing associates with slow and lazy, to painful and strangling.
When the sequence of applied manipulations is not obvious, the volume is called a Free shaper (Figure 5a). The sinuous balustrades and louvers of the Figure 5b buildings are single-curved. Buildings with protruding elements that make the façades seem double curved, are classified in the special category Slicers. Figure 5c shows a canyon-like cut-out. The freely curving façade juxtaposes the box-like overall shape. The glass industry has for many years been lagging behind in developing production facilities for such glass. If this project is executed with freely curving insulated glass panes, it will be a major breakthrough.
Figure 5a: Tour Phare, Paris (by Morphosis)
Figure 5b: Slinky Twins, Paris (by PCA)
Figure 5c: Opus, Dubai (by Zaha Hadid) With architects getting accustomed to software modeling tools, new shapes are emerging. All pictured buildings in this article, except maybe the Cobra Towers, are in the process of being built, or are finished. They are a minor part of what is being realized globally. Many more will arise when freely curved panes become more affordable. Development of production facilities for freely curved glass is speeding up. An aluminum curtain wall framing system for such façades is available: the Alcoa/Kawneer AA100Q-Twist system. Education on the geometrical aspects of complex geometry buildings is highly eased by the recently published book Architectural Geometry (Pottman, et al). It elaborates in a very accessible way on the
various topics that architects and product designers come across when modeling on their computer. The CAD-tool shape scheme connects to the descriptions and names used in the book. A few years ago, many shapes described in the scheme would have seemed mere theoretical - now many have been built, and in variations. New modeling tools and new computer based structural calculations will bring new shaping of high-rises.▪
