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The Burj Khalifa is the tallest building in the world, standing at a height of 828 m (2,716.5 ft). It is not just a work of art, but a unique feat in design and engineering. This stunning building in Dubai became a symbol of the rich and dynamic Middle East and personifies the grand vision of the Arab world. The Burj Khalifa is also a beacon of international cooperation and progress and sets new benchmarks in global construction and unprecedented figures for the next generation of skyscrapers.
Designing the Burj Khalifa
The design of the Burj Khalifa came from a high-profile design competition attracting some of the world’s greatest designers and architects. Chicago-based master of ultra-tall skyscrapers, Skidmore, Owings & Merrill LLP, won the contract. Adrian Smith FAIA, RIBA was their consulting design partner. The final design was extensively studied to ensure the proposed structure would be safe under all conditions while meeting the unique, luxurious requirements of the proposed occupants.
The Structure of the Burj Khalifa
The tower has a three-lobed footprint and a Y-shaped floor plan with three wings based around a central core, which provides torsional resistance and strength to the entire structure. This modular structure ensures a stable configuration and good floor plates for the load of residential construction. There are 26 helical levels reducing the tower’s cross-section as it goes skyward. The central core of the skyscraper emerges at the top, culminating in a sculpted spire. The tower features several onion domes, typical of ancient Islamic architecture.
The foundation of the superstructure incorporates a huge reinforced concrete mat measuring 3.7 m thick, backed up by bored reinforced concrete piles. A cathodic protection system incorporated under the concrete mat minimizes the harmful effects of corrosive chemicals in the groundwater potentially affecting the long term stability of the reinforced metal components. The whole design was finalized after extensive seismic and geotechnical studies.
The Inauguration of the Burj Khlaifa, 04/01/2010, Dubai. Courtesy of the Dubai Mall Channel.
The podium serves as a base for anchoring the tower and provides access to the three different levels of the tower from three sides. The entry pavilions are fully glazed and have a suspended cable-net structure enabling separate entries for the corporate suites and residences at different levels of the massive structure.
To assess how wind influences the skyscraper and its inhabitants, more than 40 wind tunnel tests were carried out. These included climate testing and facade pressure tests at both the base and the terraces. Ultra-tall towers like these are generally affected by the stack or chimney effect, which is caused by the difference in temperature and pressure with altitude. The Burj Khalifa was subjected to special studies to assess the effect of this phenomenon and make the necessary changes to the building design to mitigate the effects.
Aesthetic Components of the Burj Khalifa
The high rise boasts several extravagant aesthetic design features, including a park spanning 11 hectares with greenery and several water features, and about 3,000 underground parking spaces. The tower exterior also has 18 building maintenance units, equipped with cradles for window washing and facade cleaning, which are only visible when in use. It takes about 3 to 4 months to clean the entire exterior of the ultra-tall tower, with all 18 maintenance units functioning.
Interior Design of the Burj Khalifa
Nada Andric, the award-winning designer from Skidmore, Owings & Merrill LLP led the interior design for the tower. Nada incorporated modern features and Islamic culture. The design includes Venetian stucco walls, silver travertine and stone flooring, and handmade rugs. The Burj Khalifa also features stainless steel, polished dark stones, and glass in its interior design. The interior of the building is adorned with more than 1,000 works of art by popular Middle Eastern and international artists.
Accommodation in the Burj Khalifa
The Armani Hotel adorns Levels 38 and 39 of the tower and levels 9 through 16 house residences by Armani. The hotel has a total of 160 rooms.
Floors 45 to 108 house expensive private homes. The rest of the floors incorporate a mix of corporate suites, a restaurant at level 122 and a public observatory at level 124. The homes in the tower have access to KY lobbies at levels 43, 76, and 123 with facilities such as jacuzzis, swimming pools, and recreational rooms. The pools open to the outside balcony and are for residents only.
Construction of the Super-Tall Tower
In January 2004, excavation began for the construction of this global icon and it took just 1,325 days to build. In September 2009, the tower topped out with the completion of its spire and exterior cladding was completed by January 2010. It took 22 million man-hours to create the world’s tallest free-standing structure. Involving over 380 on-site technicians and skilled engineers, the construction started at the rate of 20 to 30 panels per day during its initial installation and progressed up to 175 panels per day.
The structural system of the tower is a “buttressed core” with a high-performance concrete wall construction. Corridor walls from the core extend to the end of each wing to become thick hammerhead walls. The system is complete with flat plate floor construction and perimeter columns, making the tower both laterally and torsionally stiff.
The laying of the concrete and steel foundation of the structure required more than 45,000 m3 (110,000 tonnes) of concrete. The foundations have 192 piles buried at a depth of over 50 m (164 ft). About 39,000 tonnes (43,000 ST; 38,000 LT) of steel rebar (reinforced steel bar) and 330,000 m3 (431,600 cu yd) of concrete were used to construct the tower.
The amount of aluminum used in the tower is equivalent to the aluminum in five A380 aircrafts. The exterior cladding of the tower is made up of textured stainless steel spandrel, glass, aluminum, and stainless steel vertical tubular fins. About 26,000 hand-cut glass panels are found in this exterior cladding.
The reinforced concrete core walls of the tower were cast in situ by pumping concrete from ground level to a height of 601 m, breaking the Taipei 101’s (world’s second tallest building) pumping record of 470m. During pumping, the concrete pressure was about 200 bars. The quantity of rebar used in the construction of the ultra-tall structure is 31,400 metric tons and the length of stainless steel bull nose fins in the tower is 293 times the height of the Eiffel Tower in Paris.
Interesting Facts about the Burj Khalifa
The Burj Khalifa is an unbelievable feat of engineering, design, innovation, and opulence. Apart from being the tallest building the world has ever seen, it also became the world’s tallest structure, breaking the record of the KVLY-TV mast in Blanchard, North Dakota, and the tallest free-standing structure, beating the record of Toronto’s CN Tower.
It also has a world record for its 512m high aluminum and glass facade installation and enjoys other superlatives for having the world’s greatest number of floors in a building, the longest elevator in the world, the highest outdoor observation deck, and highest occupied floor. If the 31,400 metric tons of rebar used in this tower were laid end to end, it would be enough to cover a quarter of the way around the whole world!
The Burj Khalifa has aroused global curiosity and its observatory at level 124 offers a brilliant bird’s eye view of the world and ever-changing development of Dubai below. A high-speed elevator takes visitors to the observatory deck at a speed of 10 m/s, where glass walls extend from floor to ceiling offering an unobstructed, 360-degree view of the city, ocean, and desert. Visitors can walk around the full perimeter of the deck for comprehensive views from different angles and venture out to the open-air terrace for a sweeping, breezy view.
Sources and Further Reading
This article was updated on 11th February, 2020.