How Taiwan’s tallest skyscraper withstands earthquakes

By Oscar Holland, CNN

Published 6:23 AM EDT, Thu April 4, 2024

The Taipei 101 building in Taiwan's capital was the world's tallest skyscraper from 2004 to 2007.

CNN —

The deadly 7.4 magnitude earthquake that hit Taiwan on Wednesday and left at least 9 people dead, also damaged 770 buildings.

In the capital Taipei, just 80 miles away from the epicenter, buildings also shook violently during what was Taiwan’s strongest earthquake in 25 years. But in a triumph of modern engineering, the soaring Taipei 101, once the world’s tallest skyscraper, emerged from the island’s latest seismic event undamaged.

Footage from the quake appears to show the 1,667-foot-tall tower slightly swaying, its structural flexibility helping to counter the powerful motion of the quake. This movement perfectly demonstrated how the skyscraper’s single most important defense against earthquakes is the very material it is constructed from: reinforced concrete.

Combining concrete’s compressive strength with steel’s tensile strength, the material makes the building flexible enough to sway, yet rigid enough to resist high winds and the typhoons that frequently hit Taiwan. (The principle that buildings can endure seismic forces by moving with them, rather than against them, has underpinned traditional architecture in earthquake-prone East Asian countries for centuries, from Japanese pagodas to Chinese palaces.)

High within the tower, however, another technological innovation helps protect the 101-story skyscraper — a huge orb-like device known as a tuned mass damper.

A 660-ton spherical device called a tuned mass damper swings like a giant pendulum in the skyscraper's upper floors.

Giant counterweight

Suspended from 92 thick cables between the 87th and 92nd floors, the golden steel sphere can move about 5 feet in any direction. As a result, it acts like a pendulum that counteracts (or “dampens”) swaying motions.

“It’s essentially a very large counterweight,” explained Stefan Al, author of “Supertall: How the World’s Tallest Buildings Are Reshaping Our Cities and Our Lives,” in a phone interview. “In the case of Taipei 101, it’s 660 tons. That seems really heavy, but if you compare it to the overall weight of the building, it’s just a fraction.

“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,” Al said, explaining that hydraulic cylinders between the ball and the building convert this energy into heat, which is then dispersed.

Tuned mass dampers are used in skyscrapers around the world, including the “super-skinny” Steinway Tower in New York and Dubai’s sail-shaped Burj al-Arab, which has 11 of them. The device crucially protects against the violent motion caused by “harmonic vibration,” which can cause structural failure during an earthquake, Al said.

“(That’s) when buildings start to vibrate at their own resonance,” he said, comparing the phenomenon to a tuning fork. “This can lead to a collapse, (as the building) will start shaking faster and faster and faster.”

Tuned mass dampers, which are also known as harmonic absorbers, are “tuned” to resonate at the same frequency as the building — but with wavelengths starting earlier or later, helping to dissipate the potentially catastrophic energy.

The stability they provide can also reduce the uncomfortable — or even nauseating — effect swaying can have on a building’s occupants in high winds.

How Taiwan’s tallest skyscraper withstands earthquakes

台湾最高的摩天大楼如何抵抗地震

The deadly 7.4 magnitude earthquake that hit Taiwan on Wednesday and left at least 9 people dead, also damaged 770 buildings.

台湾周三发生地震，造成至少9人死亡同时摧毁了770座建筑。

In the capital Taipei, just 80 miles away from the epicenter, buildings also shook violently during what was Taiwan’s strongest earthquake in 25 years. But in a triumph of modern engineering, the soaring Taipei 101, once the world’s tallest skyscraper, emerged from the island’s latest seismic event undamaged.

距离震中心仅仅80英里的省会台北，在台湾25年来最强的地震时建筑物也是剧烈摇晃。但现代工程的成功，让曾经是世界最高摩天大楼的高耸的台北101在岛上最近的地震中未受到损坏。

Footage from the quake appears to show the 1,667-foot-tall tower slightly swaying, its structural flexibility helping to counter the powerful motion of the quake. This movement perfectly demonstrated how the skyscraper’s single most important defense against earthquakes is the very material it is constructed from: reinforced concrete.

地震的录像显示，这座1667英尺高的高楼轻微摇晃，其结构灵活性有助于对抗地震的强大震动。这一震动完美地展示了摩天大楼抵御地震的最重要防御手段是其建造材料：钢筋混凝土。

Combining concrete’s compressive strength with steel’s tensile strength, the material makes the building flexible enough to sway, yet rigid enough to resist high winds and the typhoons that frequently hit Taiwan. (The principle that buildings can endure seismic forces by moving with them, rather than against them, has underpinned traditional architecture in earthquake-prone East Asian countries for centuries, from Japanese pagodas to Chinese palaces.)

这种材料结合了混凝土的抗压强度和钢材的抗拉强度，使建筑足够灵活的进行摇摆，但又足够坚硬，可以抵御频大风和繁袭击台湾的台风。（几个世纪以来，建筑物可以与地震一起活动而不是对抗地震力这一原则加固了处于地震带的东亚国家的传统建筑，从日本的宝塔到中国的宫殿。）

High within the tower, however, another technological innovation helps protect the 101-story skyscraper — a huge orb-like device known as a tuned mass damper.

然而，在大楼的高处，另一项技术创新可以保护这座101层的摩天大楼——一种被称为调谐质量阻尼器的巨大球体状装置。

Giant counterweight

巨型平衡物

Suspended from 92 thick cables between the 87th and 92nd floors, the golden steel sphere can move about 5 feet in any direction. As a result, it acts like a pendulum that counteracts (or “dampens”) swaying motions.

这个金色的钢球悬挂在87层和92层之间的92根粗钢索上，可以向任何方向移动约5英尺。因此，它就像一个钟摆，抵消（或“阻尼”）摇摆运动。

“It’s essentially a very large counterweight,” explained Stefan Al, author of “Supertall: How the World’s Tallest Buildings Are Reshaping Our Cities and Our Lives,” in a phone interview. “In the case of Taipei 101, it’s 660 tons. That seems really heavy, but if you compare it to the overall weight of the building, it’s just a fraction.

“这本质上是一个非常大的平衡物”，《超高层建筑：世界上最高的那些建筑如何重塑我们的城市和生活》一书的作者Stefan Al在接受电话采访时解释道，“以台北101为例，它有660吨。这看起来很重，但如果你把它与大楼的整体重量相比，它只是一小部分”。

“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,” Al said, explaining that hydraulic cylinders between the ball and the building convert this energy into heat, which is then dispersed.

“当大楼开始摇晃的时候，（调谐质量阻尼器）会朝反方向运动。对于台北101，它是悬着的，在大楼摇晃的时候它有滞后性，朝着反方向运动以吸收动能”，Al说道，并解释到球体和建筑物之间的液压缸将这些能量转化为热量，随后分散掉。

Tuned mass dampers are used in skyscrapers around the world, including the “super-skinny” Steinway Tower in New York and Dubai’s sail-shaped Burj al-Arab, which has 11 of them. The device crucially protects against the violent motion caused by “harmonic vibration,” which can cause structural failure during an earthquake, Al said.

调谐质量阻尼器被用于世界各地的摩天大楼，包括纽约的“super-skinny” Steinway大厦和迪拜的帆形阿拉伯大厦，其有11个调谐质量阻尼器。该装置对防止“谐波振动”引起的剧烈震动起到了至关重要的保护作用，谐波振动会在地震中导致结构破坏，AI说道。

“(That’s) when buildings start to vibrate at their own resonance,” he said, comparing the phenomenon to a tuning fork. “This can lead to a collapse, (as the building) will start shaking faster and faster and faster.”

“建筑物就开始以自己的谐振振动，”他说道，并将这种现象比作音叉“。这可能导致倒塌，因为建筑物将开始越来越快地振动。”

Tuned mass dampers, which are also known as harmonic absorbers, are “tuned” to resonate at the same frequency as the building — but with wavelengths starting earlier or later, helping to dissipate the potentially catastrophic energy.

调谐质量阻尼器，也被称为谐波吸收器，被“调谐”到与建筑物相同的共振频率，但波长不同步，这样有助于分散可能的毁灭性能量。

The stability they provide can also reduce the uncomfortable — or even nauseating — effect swaying can have on a building’s occupants in high winds.

其带来的稳定性还可以减少大风摇晃对建筑物里的人们的产生不舒服甚至恶心的感觉。