Taipei Financial Center

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 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 . 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 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 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 metric tons (1,100 short tons) - 1,320 metric tons (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, and killed five people in the accident. An inspection afterwards showed no structural damage to the building and construction soon resumed.
Thornton-Tomasetti Engineers along with Evergreen Consulting Engineering designed a 660 metric tons (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 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 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 metric tons (7 short tons), sit at the tip of the spire. These prevent 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 7 metric tons (8 short tons).