TAIPEI (Taiwan News) -- As a testament to the power of Thursday's (April 18) magnitude 6.1 earthquake, Taipei 101's damper recorded the largest movement in its history due to an earthquake, as intensity level 4 shock waves struck the nation's capital.
When the magnitude 6.1 struck, ironically at exactly 1:01 p.m., Taipei 101's mass damper moved by 20 centimeters, the most due to an earthquake in its 15-year history, according to Taipei 101. The tuned mass damper is a device that is designed to sway to offset movements in the building caused by strong gusts and earthquakes.
The second largest movement due to an earthquake in its history was when it swayed by 15 centimeters after a magnitude 6.3 earthquake struck off the coast of Hualien in 2015. The most the damper has moved in history was at 6:59 a.m. on Aug. 8, 2015, when it swayed by 100 centimeters due to powerful wind gusts from Typhoon Soudelor.
An employee in Taipei 101 told CNA that the swaying of the building was exceptionally noticeable and many workers in the office were alarmed. The employee said that some women even began to scream.
The damper is a sphere that is 5.5 m in diameter, weighs 660 tons, and is suspended from the 92nd to the 87th floor. It consists of 41 circular steel plates of varying diameters, each 125 mm thick, welded together.
According to Taipei 101, the sphere can offset the swaying of Taiwan's tallest tower from wind gusts and earthquakes by up to 40 percent.
Video showing the massive damper sway during the earthquake: