How Taipei 101, Taiwan’s tallest skyscraper, stands tall amid earthquakes

At least ten people died, and hundreds were injured after a 7.4 magnitude earthquake struck Taiwan’s east coast on April 3. The quake, which was followed by strong aftershocks, was the most powerful in 25 years, causing significant damage to several buildings.
Hualien County, the quake’s epicentre, lies just 80 miles from Taipei, the country’s capital. Despite the widespread damage to structures across the country, Taipei 101, once the tallest skyscraper in the world, remained unscathed. While the 1,667-foot-tall tower slightly swayed during the quake, it stood firm against the seismic forces.
Since the island nation has a long history of catastrophic earthquakes, it has long integrated seismic requirements into its building codes.
In 1999, the country faced one of the deadliest quakes that killed 2,400 people. It also demolished more than 51,000 buildings and damaged an equivalent number of buildings, according to Taiwan’s National Center for Research on Earthquake Engineering (NCREE).
Since then, Taiwan has enacted stricter building codes emphasising quake-resistant construction techniques. According to NCREE, around 80 buildings in Taiwan in 2009 had seismic features, which grew to more than 1,000 by 2022.
Taipei 101’s resilience against seismic activity can be attributed to several factors. Its construction materials, a combination of concrete and steel, were chosen for their flexibility and strength, enabling the skyscraper to endure quakes. Secondly, the building rests on deep foundations supported by reinforced concrete and steel piles drilled into the bedrock. Furthermore, its core is linked to outer mega-columns via sturdy steel outrigger trusses to enhance stability, reported CNN.
Taipei 101’s stability also depends on the mass damper—a spherical device suspended from 92 thick cables between the 87th and 92nd floors.
“When a building starts to shake, (the tuned mass damper) will move in the opposite direction. In the case of Taipei 101, it’s suspended… so it will lag behind as the tower sways and will absorb the kinetic energy by moving in the opposite direction,” Stefan Al, author of ‘Supertall: How the World’s Tallest Buildings Are Reshaping Our Cities and Our Lives’ told CNN.