Taipei 101

Taipei 101 (Traditional Chinese: 臺北101 or 台北101; Simplified Chinese: 台北101; Hanyu Pinyin: Táiběi Yīlíngyī; Wade-Giles: T'ai-pei I-ling-i) is a 101-floor landmark skyscraper located in Taipei, the capital of Taiwan. The building, designed by C.Y. Lee & Partners and constructed by KTRT Joint Venture, is the world's tallest completed skyscraper. Taipei 101 received the Emporis Skyscraper Award in 2004. It has been hailed as one of the Seven New Wonders of the World (Newsweek magazine, 2006) and Seven Wonders of Engineering (Discovery Channel, 2005). Taipei 101 is managed by the International division of Chicago based Urban Retail Properties Co.

The name of the landmark reflects its home city and floor count, of course, but also its location in Taipei's 101 postal district, a rapidly developing hub of international activity in Taiwan. The number is pronounced in English simply as One Oh One. (See also Exterior symbolism below.) The original name planned for the building, Taipei World Financial Center, derived from that of its owner, Taipei Financial Center Corporation and the formal name of the structure in Chinese: literally, Taipei International Financial Center (Traditional Chinese: 臺北國際金融中心; pinyin: Táiběi Guójì Jīnróng Zhōngxīn).

On 2007-07-21 Taipei 101 was overtaken in height by the Burj Dubai in Dubai, UAE, upon the completion of that building's 141st floor. Taipei 101 retains its title until the Burj Dubai is completed, though, as international architectural standards define a "building" as a structure that can be occupied.

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 meters per second and the strongest earthquakes likely in a 2,500 year cycle.

Skyscrapers have to be flexible in strong winds yet remain rigid enough to prevent large sideways (lateral drift) movement. The resistance enables comfort for the occupants and protects glass, curtain walls and other features from damage. Most designs achieve this 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 on the part of engineers.

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 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 the its foundation to make Taipei 101 one of the most stable buildings ever designed. The foundation is reinforced by 380 piles driven 80 meters into the ground, extending as far as 30 meters into the bedrock. Each pile is 150 cm in diameter and can bear a load of 1100-1450 tons. The stability of the design became evident during construction when, on 2002-03-31, a 6.8-magnitude earthquake rocked Taipei. The tremor was strong enough to topple two construction cranes from the 56th floor, then the highest, and kill five people in the accident. An inspection still showed no structural damage to the building and construction soon resumed.

Thornton-Tomasetti Engineers along with Evergreen Consulting Engineering designed a 662 metric ton steel pendulum that serves as a tuned mass damper. Suspended from the 92nd to the 88th 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 layered steel plates, each with a height of 125 mm being welded together to form a 5.5-meter diameter sphere. Another two tuned mass dampers, each weighing 4.5 tons, sit at the tip of the spire. These prevent cumulative damage to the structure due to strong wind loads.

Taipei 101's characteristic blue-green glass curtain walls are double glazed, offer heat and UV protection, and can sustain impacts of eight tons.