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Tuned Mass Damper of Taipei 101

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Re: Tuned Mass Damper of Taipei 101

#31

Post by saryant »

chiph wrote: post #6

The shape/design was copied by the Westworld designers for the quantum supercomputer "Rehoboam" in season 3. https://www.youtube.com/watch?v=TgBtBkW0u8Y Also - given the large motion of the damper in today's earthquake, why weren't more people freaking out? I'm also curious about how much the dampers (shock absorbers) heated up from restraining the movement of the ball.

I was on the ground floor of a modern building in Tokyo when Fukushima happened and barely felt a thing. These systems are remarkably effective.

Re: Tuned Mass Damper of Taipei 101

#32

Post by bhrgunatha »

graderjs wrote: post #25
jwmoz wrote: post #23

I've felt 4 earthquakes in 2 days. The bigger one was when I was in a department store 11th floor in Xinyi, horrible, horrible. One of the reasons I can't live here permanently. Last year there were much more earthquakes.

Do you remember that 7.2 a couple years ago? Much closer to Taipei then these Hualien quakes. That felt really sickening to me. The ones yesterday I felt pretty sick for a while too

Are you misremembering the 6.4 from 2018 in Hualien?

There were no 7+ magnitude quakes in recent years. [1] The closest is 2016 at 7.1 which took out some undersea internet cables the caused a reduction in spam worldwide of 50%. [2]

[1] https://en.wikipedia.org/wiki/Taiwan_earthquakes [2] https://en.wikipedia.org/wiki/2006_Hengchun_earthquakes

Re: Tuned Mass Damper of Taipei 101

#33

Post by HyperSane »

samstave wrote: post #26
LegitShady wrote: post #18

Earlier quoted context omitted.

Tall buildings are built with deep foundation systems. Taipei 101 has 380 1.5m diameter piles tied into a 3m thick concrete raft that creates its basement. The piles rock socketed into some 40-60m below the structure. those piles are socketed up to 30m into the bedrock. https://www.civilengineeringforum.me/the-tower-of-taipei-101... https://structures-explained.com/taipei-101-structural-engin... It is designed to res…

Quoted post unavailable.

The Millennium Tower piles do not rest on bedrock, it was supposed to use friction with the soil instead. This is cheaper and CAN work but it is far easier to get wrong than having the piles rest directly on bedrock.

Re: Tuned Mass Damper of Taipei 101

#35

Post by iancmceachern »

z9znz wrote: post #2

> Safety comes at a hefty price, however, as the tower’s tuned mass damper cost $4 million to build. A paltry 4 million for a project which cost almost 2 billion (USD); and I imagine it resulted in some measurable reductions in insurance cost. But I wonder, what happens if the entire land that it stands on shifts and is no longer level? That pendulum won't help right a tilted building, and in fact it will move the ce…

It's not a price, it's what enables it. Without the damper, the building would have to be shorter.

Re: Tuned Mass Damper of Taipei 101

#36

Post by max51 »

Passive mass dampers are used for wind, not earthquakes. their performance for earthquake is so bad that researchers don't even bother studying it.

If you use google scholars, the only results you get are researchers mentioning in their intro that passive systems don't work for seismic and then they propose an active (ei. with motors, pumps, etc.) system or a semi-active system (ef. fluid dampers with electronically controlled valves).

Passive mass dampers (ei. no valves, motors, etc.) like the one in Taipei 101 require too long to resonate with the earthquake and dissipate energy. by the time they start doing work, the earthquake is over.

This subject is like airplane lift explanations, the misinformation gets repeated so much that it even make its way into college textbooks.

Re: Tuned Mass Damper of Taipei 101

#37

Post by fisherjeff »

doomlaser wrote: post #4

Footage of it in motion during today's 6.8 magnitude earthquake: https://www.youtube.com/watch?v=qnSh8C40i1s

I can’t say that my first reaction to a major earthquake would be “let’s go up to the 89th floor and see what that 1.5 million pound ball is doing!”

Re: Tuned Mass Damper of Taipei 101

#38

Post by vl »

max51 wrote: post #36

Passive mass dampers are used for wind, not earthquakes. their performance for earthquake is so bad that researchers don't even bother studying it. If you use google scholars, the only results you get are researchers mentioning in their intro that passive systems don't work for seismic and then they propose an active (ei. with motors, pumps, etc.) system or a semi-active system (ef. fluid dampers with electronically…

Or how skates work on ice.

Re: Tuned Mass Damper of Taipei 101

#39

Post by luobogao »

graderjs wrote: post #24
doomlaser wrote: post #4

Footage of it in motion during today's 6.8 magnitude earthquake: https://www.youtube.com/watch?v=qnSh8C40i1s

It was actually a 6.9 https://earthquake.usgs.gov/earthquakes/eventpage/us7000i90q...

Actually Taipei was only around 2. Magnitudes 6-7 were in the epicenter near Taitung, fairly far away - about 200-300km.

Re: Tuned Mass Damper of Taipei 101

#40

Post by graderjs »

bhrgunatha wrote: post #32
graderjs wrote: post #25

Earlier quoted context omitted.

Do you remember that 7.2 a couple years ago? Much closer to Taipei then these Hualien quakes. That felt really sickening to me. The ones yesterday I felt pretty sick for a while too

Are you misremembering the 6.4 from 2018 in Hualien? There were no 7+ magnitude quakes in recent years. [1] The closest is 2016 at 7.1 which took out some undersea internet cables the caused a reduction in spam worldwide of 50%. [2] [1] https://en.wikipedia.org/wiki/Taiwan_earthquakes [2] https://en.wikipedia.org/wiki/2006_Hengchun_earthquakes

No there was definitely a 7 a few years back, I didn't say it was in Hualien. Do I really need to check this, for your convincing, can't you just believe me?

alright I checked: this is weird, but can't remember this one being a 6. Anyway, it was 7 on the Taiwan intensity scale. Maybe that's where I got it from?

https://scweb.cwb.gov.tw/en-us/earthquake/details/EE20190418...

https://en.wikipedia.org/wiki/2019_Hualien_earthquake

f off downvoters

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