World's second-tallest skyscraper completed in Shanghai
Following six years of construction, work was recently completed on the world's second-tallest skyscraper, the Shanghai Tower. Rising an impressive 632 m (2,073 ft) over Shanghai, China, the US$2.4 billion mixed-use project features an interesting design that twists 120 degrees from bottom to top, in order to mitigate the effects of wind on the structure.
Designed by international firm Gensler, the Shanghai Tower is officially recognized as the world's second-tallest building by the CTBUH (Council on Tall Buildings and Urban Habitat), after Dubai's Burj Khalifa. However, it is certain to slip to third position once the Jedah Tower is completed in 2020.
The size of the project boggles the mind. Located in the Lujiazui Financial Center in Shanghai, which was still farmland a mere two decades ago, the clay-based soil the tower rests upon required 1,079 concrete and steel piles to be driven into the ground for use as supports. Laying the foundation involved a fleet of trucks pouring concrete for 63 straight hours.
The tower features 128 floors and comprises 420,000 sq m (4,520,842 sq ft) of floorspace. Its highest occupied point is at 561.3 m (1,841 ft) and to get there, occupants make use of one of 106 Mitsubishi-designed elevators, which travel at a speed of 40 mph (64 km/h).
According to Gensler, the building's tapering form reduces wind loads by 24 percent. Furthermore, the reduction in materials that this allowed saved $58 million from the total budget of the project.
The interior of the building is mostly taken up by high-end office space, with some retail areas and hotel rooms, plus an observation point/cultural area at the top. It's also rated LEED Gold (a green building standard) and features some energy-saving design and technology.
A double-layered glass skin improves insulation and allows natural light to permeate inside, while the facade sports a total of 270 wind turbines that provide the power needed for external lighting. The building's funnel-shaped parapet channels rainwater into large tanks, which is used for air-conditioning and heating systems. A graywater system is also installed, but operable windows were decided against on account of the poor local air quality.