Burj Khalifa

Burj Khalifa (Arabic: برج خليفة) is a skyscraper in the city of Dubai in the United Arab Emirates. Construction started on September 21, 2004. On July 21, 2007, the Burj Khalifa took over the title of "tallest building in the world" from Taipei 101 in Taiwan. The tower reached its highest point on January 17, 2009, at a height of 828 meters. Including antennas and flagpoles, the height is 829.8m. The building was opened with grand fireworks on January 4, 2010.

During the construction the tower was known as Burj Dubai (Arabic: برج دبي, literally: Tower of Dubai), but a few hours before the opening the tower was renamed Burj Khalifa, a reference to Khalifa bin Zayed Al Nahayan, president of the United Arab Emirates and Emir of neighboring Abu Dhabi. This name change took place after considerable financial support to the Dubai-ravaged Dubai from the Emirate of Abu Dhabi.

Architecture and design

The Burj Khalifa was designed by the American architectural firm Skidmore, Owings and Merrill from Chicago. They also designed the Willis Tower in Chicago and the Jin Mao Tower in Shanghai. The main contractor was the South Korean Samsung C&T Corporation, with the important subcontractors being the Belgian Besix and the local Arabtec Construction. The project developer is Emaar Properties from Dubai.

The floor plan of the tower is built in the shape of the Hymenocallis, a common desert flower in the region. The tower is made up of three elements around a central core. The concrete body of the building is over 575 meters high. The roof height is around 636 meters. Estimates about the final height varied widely. The companies involved first kept this fearfully secret for fear that the height of the Burj Khalifa would be surpassed in a short time. Eventually the counter remained at 828 meters.

In addition to office space and 900 apartments, space is reserved in the tower for a large hotel. The hotel interior was designed by fashion designer Giorgio Armani. The first Armani Hotel occupies 15 of the 37 lower floors.

It is expected that on floors 37 to 108, apartments will be built. According to the project developer, all apartments were sold in eight hours. A swimming pool is being built on the 78th floor, a lobby on the 123rd floor and an observation deck on the 124th floor. Furthermore, the world's highest nightclub is located on the 143rd floor and the world's highest mosque can be found on the 158th floor.

Records

The tallest building ever built by people breaks many records. Some of them are described below:

• In February 2007, the Burj Khalifa surpassed the Willis Tower, which at that time had the largest number of floors in the world. The building has 163 floors in total. These are 35 floors more than the number 2, Shanghai Tower (128) and 40 floors more than number 3, Lotte World Tower (123).
• On September 13, 2007, the tower reached a height of 555 meters. This passed the tallest freestanding structure in the world, the CN Tower in Toronto.
• On 7 April 2008, project developer Emaar reported that the Burj Khalifa had reached a height of 629 meters (and 160 completed floors). Now the KVLY TV mast in North Dakota (628.5 meters) had also passed. The Burj Khalifa thus surpassed the tallest structure on earth.
• The height of 688 meters was achieved on 1 September 2008. With this, the only height record that was still standing, that of the tallest structure ever, was already broken by 41.5 meters. For this the height record was in the name of the 646.4 meter high mast of Radio Warsaw, which suddenly collapsed in 1991 during maintenance work.
• On January 23, 2011, the world's highest restaurant, called At.mosphere, opened in the Burj Khalifa. The restaurant is located on the 122nd floor, at a height of 422 meters.
• Also a chocolate replica of the Burj Khalifa, made by Andrew Farrugia, broke a record on November 30, 2014. The replica consisted of 4200 kg of Belgian chocolate and stands at 13.5 meters in the Guinness Book of Records as the highest construction in chocolate.

Technology

The tower had the world's fastest lifts, with a speed of 42 km/h (12 m/s) (this record was meanwhile broken by the lifts of the G1 Tower in Hitachinaka, Japan: 48 km/h or 13 m/s) and a capacity of 21 people. It is the highest lift installation in the world. The water installation will supply the tower with an average of 946,000 liters per day. The maximum electricity supply is estimated at 36 MVA. The cooling system will use the equivalent of more than 10.2 million kilos of melted ice as cooling water. The tower forms the center of a multifunctional complex, which includes the adjacent largest mall in the world, the Dubai Mallincludes. The tower is located on an artificial pond with the largest fountain in the world.

Because of the technology, the tower was the main subject of an episode of National Geographic's Big, Bigger, Biggest.

Trivia

The building is so high that the sun sets 3 minutes later on the top floor than on the bottom.