As of 2013, the tallest building in the world that has been completed and is in operation is the Burj Khalifa in Dubai, United Arab Emirates. The Burj Khalifa, which took six years to complete, is not only the tallest building in the world, but also holds a number of other "tallest" titles, including tallest freestanding structure in the world, tallest number of floors, tallest number of occupied floors, tallest outdoor observation deck (124 floors), tallest bar (144 floors), and tallest bar (144 floors). The highest number of floors, the highest number of floors in use, the highest outdoor observation deck (124 floors), the highest bar (143 floors), the highest mosque (158 floors), the largest elevator in the world, the highest service elevator, and even the Dubai Fountain, which has the world's highest water jet with a column of water that reaches 275 meters high, is the "highest spraying fountain in the world".
The Burj Khalifa is 828 meters high, with 162 floors above ground, almost the height of two Shanghai Jinmao towers (88 floors, 420.5 meters) overlapping. Designed by the American firm SOM Architects in collaboration with architect Adrian Smith, construction of the Burj Khalifa began in January 2004 and was completed on January 4, 2010, when it opened.
The completed Burj Khalifa
Since ancient times, people have regarded the construction of high-rise buildings as a symbol of strong economic strength and superior technology, so the competition for the "world's tallest" has always been a fiercely competitive project, and the construction of Burj Khalifa has been a process of constantly breaking world records. In February 2007, it surpassed the Wells Tower (110 floors above ground and 443 meters high) in Chicago, U.S.A., to become the tallest building in the world in terms of the number of floors; in July, it surpassed the 508-meter Taipei 101 Building to become the tallest building on the ground; in September, it surpassed the 555.33-meter-high National Television Tower of Canada in Toronto, U.S.A., to become the tallest freestanding structure in the world; in April 2008 , surpassing the 628.8-meter-high KVLY TV tower in North Dakota, U.S.A. (held in place by steel cable ties) to become the world's tallest man-made structure; in January 2009, Burj Khalifa reached its final height of 828 meters, creating a new Guinness Book of Records.
The architects of the Burj Khalifa created a three-petal structure inspired by the form of a local desert plant, the spider orchid. Each wing of the tower's spire extends outward from the core, just as the petals of a flower grow from its stem. As the tower rises, this Y-shaped structural body recedes step by step, forming a stable structure with a large bottom and a small top. In this way, it is able to avoid the formation of wind vortices at the tower's surface. The core in the center to the top forms a rather sculptural spire that can be seen from as far away as about 100 kilometers. The building houses a hotel below the 39th floor, ultra-luxury apartments from the 45th to 108th floors, and an observation deck on the 124th floor, from which you can stand overlooking the entire city of Dubai. The Burj Khalifa is also used as a club, library, restaurant, pool and mosque, with a total construction investment of more than $7 billion.
To build the Burj Khalifa, the total **** used 330,000 cubic meters of concrete, 39,000 tons of steel and 142,000 square meters of glass, and used 45,000 cubic meters of more than 110,000 tons of concrete for the foundations alone, and drove 192 piles that were more than 50 meters deep. The skyscraper used 31,400 tons of rebar, which would have circled the globe a quarter of an inch if it had been connected end to end.
Just as the Bible describes the construction of the Tower of Heaven, the Burj Khalifa is the result of the sweat and ingenuity of laborers of many nationalities around the world. At the height of construction, 12,000 workers and contractors from more than 100 countries converged on the site every day.