At over 828 metres (2,716.5 feet) and more than 160 stories, Burj Khalifa holds records for:
The Tallest building in the world
Tallest free-standing structure in the world
Highest number of stories in the world
Highest occupied floor in the world
Highest outdoor observation deck in the world
Elevator with the longest travel distance in the world
Tallest service elevator in the world
The tower was designed by Skidmore, Owings and Merrill, who also designed the Willis Tower here in Chicago and the new One World Trade Center in New York City
No stranger to Middle Eastern design, architect Adrian Smith incorporated patterns from traditional Islamic architecture, cultural and historical elements particular to the region but his most inspiring element was a regional desert flower, the Hymenocallis, is one of the organizing principles of the tower's design. The Burj Khalifa uses the bundled tube design. Like petals from a stem, the tower's wings extend from its central core. Viewed from the base or the air, Burj Khalifa is evocative of the onion domes prevalent in Islamic architecture. In addition to its aesthetic and functional advantages, the spiraling “Y” shaped plan was utilized as the structural core of Burj Khalifa. The structural system can be described as a “buttressed core”, and consists of high performance concrete wall construction. Each of the wings buttress the others via a six-sided central core. This central core provides the torsional resistance of the structure, similar to a axle. Corridor walls extend from the central core to near the end of each wing, terminating in thickened hammer head walls. These corridor walls and hammerhead walls resist the wind shears. Perimeter columns and flat plate floor construction complete the system. The tower is composed of three elements arranged around a central core. The modular, Y-shaped structure, with setbacks along each of its three wings provides an inherently stable configuration for the structure and provides good floor plates for residential. The Y-shaped plan with the wings allows for maximum outward views and inward natural light as well as reduces the wind forces on the tower. As the tower rises from the flat desert base, there are 27 setbacks in a spiralling pattern. At the top, the central core emerges and is sculpted to form a finishing spire. At its tallest point, the tower is
Excavation work began for Burj Khalifa in January 2004 and In just 1,325 days, it became the tallest free-standing structure in the world.
The superstructure is supported by a large reinforced concrete mat, which is in turn supported by bored reinforced concrete piles. The design was based on extensive geotechnical and seismic studies. The mat is 3.7 meters thick, and was constructed in four separate pours totaling 12,500 cubic meters of concrete. A high density, low permeability concrete was used in the foundations, as well as a cathodic protection system under the mat, to minimize any detrimental effects form corrosive chemicals in local ground water., and construction took 22 million man-hours.
Exterior cladding of Burj Khalifa began in May 2007 and was completed in September 2009. The vast project involved more than 380 skilled engineers and on-site technicians.
The tower accomplished a world record for the highest installation of an aluminium and glass façade, at a height of 512 meters. The exterior cladding is comprised of reflective glazing with aluminum and textured stainless steel spandrel panels and stainless steel vertical tubular fins. Close to 26,000 glass panels, each individually hand-cut, were used in the exterior cladding of Burj Khalifa. Over 300 cladding specialists from China were brought in for the cladding work on the tower. The cladding system is designed to withstand Dubai's extreme summer heat, and to further ensure its integrity, a World War II airplane engine was used for dynamic wind and water testing. The curtain wall of Burj Khalifa is