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Taipei 101
Ambition Reaches New Heights: Erecting the world’s tallest building—in an earthquake zone

By Michael Moyer

Although “World’s Tallest Building” is a fleeting title—almost every year, it seems, a different Asian capital unveils an even more audacious skyscraper plan—the technological achievements of Taipei 101 won’t soon be forgotten. Taiwan’s capital wasn’t an obvious spot for a 1,666-foot building. Not only is the city frequently buffeted by typhoons, it sits near the Pacific Ring of Fire, the most seismically active area on Earth.

To survive high winds, skyscrapers need stiffness; to survive earthquakes, they must sway. Faced with that conundrum, Thornton-Tomasetti Engineers and Evergreen Consulting Engineering devised a package of innovations that serve the $1.7-billion building’s versatile needs. For starters, they hung a 730-ton steel pendulum, called a tuned mass damper, from the 92nd floor. The movements of the damper offset strong gusts and shakes. Meanwhile, the building’s frame makes it flexible enough to absorb earthquake energy. Two dozen giant vertical columns provide support; a steel web wraps around the exterior, adding ductility; and every eight floors, outrigger trusses connect the columns in the building’s core to those on the exterior, further distributing the structural load. The final tech touch: Visitors ride the world’s fastest elevators, which travel at up to 55 feet a second. Find out more at the Taipei Financial Center website.