Taipei 101

Taipei 101, formerly known as the Taipei World Financial Center, is a landmark skyscraper located in Xinyi District, Taipei, Republic of China (Taiwan). The building ranked officially as the world's tallest from 2004 until the opening of the Burj Khalifa in Dubai in 2010. In July 2011, the building was awarded LEED Platinum certification, the highest award in the Leadership in Energy and Environmental Design (LEED) rating system and became the tallest and largest green building in the world. Taipei 101 was designed by C.Y. Lee & partners and constructed primarily by KTRT Joint Venture and Samsung C&T. The tower has served as an icon of modern Taiwan ever since its opening, and received the 2004 Emporis Skyscraper Award. Fireworks launched from Taipei 101 feature prominently in international New Year's Eve broadcasts and the structure appears frequently in travel literature and international media.

Taipei 101 comprises 101 floors above ground and 5 floors underground. The building was architecturally created as a symbol of the evolution of technology and Asian tradition (see Symbolism). Its postmodernist approach to style incorporates traditional design elements and gives them modern treatments. The tower is designed to withstand typhoons and earthquakes. A multi-level shopping mall adjoining the tower houses hundreds of fashionable stores, restaurants and clubs.Taipei 101 is owned by the Taipei Financial Center Corporation (TFCC) and managed by the International division of Urban Retail Properties Corporation based in Chicago. The name originally planned for the building, Taipei World Financial Center, until 2003, was derived from the name of the owner. The original name in Chinese was literally, Taipei International Financial Center



Height

The Taipei 101 tower has 101 stories above ground and five underground. Upon its completion Taipei 101 claimed the official records for:[2]

Ground to highest architectural structure (spire): 509.2 metres (1,671 ft). Previously held by the Petronas Towers 452 m (1,483 ft).
Ground to roof: 449.2 m (1,474 ft). Formerly held by the Willis Tower 442 m (1,450 ft).
Ground to highest occupied floor: 439.2 m (1,441 ft). Formerly held by the Willis Tower 412.4 m (1,353 ft).
Fastest ascending elevator speed: designed to be 1010 meters per minute, which is 16.83 m/s (55.22 ft/s) (60.6 km/h, 37.7 mi/h). Now it has been succeeded by Burj Khalifa's elevator whose speed of ascending is 18 m/s (64 km/h).
Largest countdown clock: Displayed on New Year's Eve.
Tallest sundial. (See 'Symbolism' below.)

Taipei 101 is the first building in the world to break the half-kilometer mark in height It also displaced the 85-story, 347.5 m (1,140 ft) Tuntex Sky Tower in Kaohsiung as the tallest building in Taiwan and the 51-story, 244.2 m (801 ft) Shin Kong Life Tower as the tallest building in Taipei.

Various sources, including the building's owners, give the height of Taipei 101 as 508.0 m (1,667 ft), roof height and top floor height as 448.0 m (1,470 ft) and 438.0 m (1,437 ft). This lower figure is derived by measuring from the top of a 1.2 m (4 ft) platform at the base. CTBUH standards, though, include the height of the platform in calculating the overall height, as it represents part of the man-made structure and is above the level of the surrounding pavement.

Structural design

The main tuned mass damper atop Taipei 101
Location of Taipei 101's largest tuned mass damper.

Taipei 101 is designed to withstand the typhoon winds and earthquake tremors common in its area of the Asia-Pacific. Planners aimed for a structure that could withstand gale winds of 60 m/s (197 ft/s, 216 km/h, 134 mph) and the strongest earthquakes likely to occur in a 2,500 year cycle.

Skyscrapers must be flexible in strong winds yet remain rigid enough to prevent large sideways movement (lateral drift). Flexibility prevents structural damage while resistance ensures comfort for the occupants and protection of glass, curtain walls and other features. Most designs achieve the necessary strength by enlarging critical structural elements such as bracing. The extraordinary height of Taipei 101 combined with the demands of its environment called for additional innovations. The design achieves both strength and flexibility for the tower through the use of high-performance steel construction. Thirty-six columns support Taipei 101, including eight "mega-columns" packed with 10,000 psi (69 MPa) concrete. Every eight floors, outrigger trusses connect the columns in the building's core to those on the exterior.

These features combine with the solidity of its foundation to make Taipei 101 one of the most stable buildings ever constructed. The foundation is reinforced by 380 piles driven 80 m (262 ft) into the ground, extending as far as 30 m (98 ft) into the bedrock. Each pile is 1.5 m (5 ft) in diameter and can bear a load of 1,000–1,320 tonnes (1,100–1,460 short tons). The stability of the design became evident during construction when, on March 31, 2002, a 6.8-magnitude earthquake rocked Taipei. The tremor was strong enough to topple two construction cranes from the 56th floor, then the highest. Five people died in the accident, but an inspection showed no structural damage to the building, and construction soon resumed.

Thornton-Tomasetti Engineers along with Evergreen Consulting Engineering designed a 660 tonnes (728 short tons) steel pendulum that serves as a tuned mass damper, at a cost of NT$132 million (US$4 million). Suspended from the 92nd to the 87th floor, the pendulum sways to offset movements in the building caused by strong gusts. Its sphere, the largest damper sphere in the world, consists of 41 circular steel plates, each with a height of 125 mm (4.92 in) being welded together to form a 5.5 m (18 ft) diameter sphere. Another two tuned mass dampers, each weighing 6 tonnes (7 short tons), sit at the tip of the spire. These prevent damage to the structure due to strong wind loads.