4 ms·

It's leaning 6 inches so I'm assuming it's going to continue to lean further and further each year unless they make modifications to the building (so lopping of

It's leaning 6 inches so I'm assuming it's going to continue to lean further and further each year unless they make modifications to the building (so lopping off the top 20 floors or whatever else that could fix or mitigate it). At which point does it lean far enough that they have to demolish the building? At which point does the entire building become a safety issue should an earthquake (or even "the big one") ever hit? Working in the city these tall buildings going up kinda worry me with the area being prone to earthquakes. I'm not a structural engineer so maybe my worries are misguided but they're there.

nikmobi 10y ago
My thoughts as well. Does anyone here have any insight on if it's misguided to worry here? Second, what exactly, if anything, can be done to fix the lean, or prevent it from leaning any further?
- the_mitsuhiko 10y ago
  Depends on what your worry is. It can lose value. There are many options to keep it straight but they all come with some disadvantages. Worst case you build something next to it and tether them together.
  - mikeryan 10y ago
    You can't really build anything next to that building. It's surrounded on three sides by major thoroughfares and a brand new terminal on the fourth.
idlewords 10y ago
Tall buildings built to seismic code are some of the safest structures to be in in an earthquake. Though you'll probably need a change of underwear afterwards: https://www.youtube.com/watch?v=NisWbAXfyWI https://www.youtube.com/watch?v=NisWbAXfyWI
- BinaryIdiot 10y ago
  Holy crap you're not kidding! That's incredibly cool and terrifying at the same time! I wonder how this tower in SF compares and if it did meet seismic code, will the sinking and leaning eventually take it out of code?
- PhantomGremlin 10y ago
  A building can have a tuned mass damper[1] to help counteract the swaying. You can even turn that into a tourist attraction of sorts.[2] [1] https://en.wikipedia.org/wiki/Tuned_mass_damper https://en.wikipedia.org/wiki/Tuned_mass_damper [2] https://www.youtube.com/watch?v=ohKqE_mwMmo https://www.youtube.com/watch?v=ohKqE_mwMmo
  - wlesieutre 10y ago
    Taipei 101 even turned it into a mascot of sorts, the Damper Baby http://www.alamy.com/stock-photo-damper-baby-and-tuned-mass-damper-in-taipei-101-it-was-the-worlds-52580647.html http://www.alamy.com/stock-photo-damper-baby-and-tuned-mass-... http://josellesoh.deviantart.com/art/damper-baby-292759048 http://josellesoh.deviantart.com/art/damper-baby-292759048
- ScottBurson 10y ago
  I was asleep on about the 20th floor of a hotel in LA in 1992 when the 7.3 Landers and 6.5 Big Bear earthquakes hit [0]. The building (which I believe was on rollers) was rocking quite noticeably. I wasn't afraid for myself, though by the large, low-frequency motion I could tell it was a very large earthquake whose epicenter was a good distance away. I hoped it hadn't just taken out San Diego. Though I'll admit, to go back to sleep and then be wakened by a second large quake (Big Bear hit about 3 hours later; it is considered a separate quake rather than an aftershock) was starting to get a bit freaky. [0] https://en.wikipedia.org/wiki/1992_Landers_earthquake https://en.wikipedia.org/wiki/1992_Landers_earthquake [1] https://en.wikipedia.org/wiki/1992_Big_Bear_earthquake https://en.wikipedia.org/wiki/1992_Big_Bear_earthquake
  - cgriswald 10y ago
raldi 10y ago
> It's leaning 6 inches so I'm assuming it's going to continue to lean further and further each year Why? Maybe it's settling into a new spot and the leaning will taper off. I think we need to wait and see what the experts say on this.
- happyslobro 10y ago
  Expert here! We need to wait and see if the angular velocity accelerates exponentially. Until then, we can't be certain that there is any hazard. You may all go back to work now. We'll measure its angle regularly and bill your insurance monthly until something or nothing happens.
- BinaryIdiot 10y ago
  Oh fair enough. That thought never crossed my mind. I kinda assumed if it starts leaning then gravity is only going to make it lean further. At least that's what it sounds like each time I read about it. But I don't know anything about structural engineering ¯\_(ツ)_/¯
  - xenadu02 10y ago
    No one really knows; it's built on landfill that used to be part of the bay and it isn't anchored to bedrock. However the rate of movement will most likely continue to slow over time and the foundation that is present will keep it from falling over anytime soon. Think Leaning Tower of Pisa, which sank and tilted slowly over many years... long enough for corrective measure to be take. Fixing it will probably require cutting holes and driving down to bedrock, then pouring new concrete. It will have to be carefully done to avoid weakening the foundation and to make sure the new Piles don't poke through the concrete like a bed of nails. The developer cheaped out... using reinforced concrete is less expensive than steel but it makes the building a lot heavier. Why the city let them skip out on anchoring to bedrock for such a tall building in an earthquake zone I have no idea. I do find it hilarious that all the other big towers going up are happily advertising their bedrock pillar work.
    - repsilat 10y ago
pitaa 10y ago
You might be interested in the story of the Citicorp Center, a building in NYC that was dangerously susceptible to being literally blown over. >...LeMessurier calculated that a storm powerful enough to take out the building hits New York every 16 years. In other words, for every year Citicorp Center was standing, there was about a 1-in-16 chance that it would collapse.[0] [0] http://www.slate.com/blogs/the_eye/2014/04/17/the_citicorp_tower_design_flaw_that_could_have_wiped_out_the_skyscraper.html http://www.slate.com/blogs/the_eye/2014/04/17/the_citicorp_t...
- m_mueller 10y ago
  They didn't even give the student recognition, sleazy basterds. Should have given her a job right away!
- kator 10y ago
  During hurricane Sandy I lived directly across from the Chase building in the financial district. The motion of the Chase building made me sea sick looking at how much it swayed in the wind. You could see the window shades flying back and forth, some office chairs moving around. The displacement was obvious with the naked eye, it reminded me of palm trees at the beach during high winds.
  - graaben 10y ago
    I worked in that building in 2012, and when we got back into the office later that week there were huge cracks running down the drywall from ceiling to floor.
  - wdr1 10y ago
    Swaying is not necessarily indicative of a problem. The Sears Tower has a fair bit of sway as well. The general idea is "bend, don't break" and allow some give in high winds.

nikmobi 10y ago

My thoughts as well. Does anyone here have any insight on if it's misguided to worry here? Second, what exactly, if anything, can be done to fix the lean, or prevent it from leaning any further?

the_mitsuhiko 10y ago
Depends on what your worry is. It can lose value. There are many options to keep it straight but they all come with some disadvantages. Worst case you build something next to it and tether them together.
- mikeryan 10y ago
  You can't really build anything next to that building. It's surrounded on three sides by major thoroughfares and a brand new terminal on the fourth.

idlewords 10y ago

Tall buildings built to seismic code are some of the safest structures to be in in an earthquake. Though you'll probably need a change of underwear afterwards: https://www.youtube.com/watch?v=NisWbAXfyWI https://www.youtube.com/watch?v=NisWbAXfyWI

BinaryIdiot 10y ago
Holy crap you're not kidding! That's incredibly cool and terrifying at the same time! I wonder how this tower in SF compares and if it did meet seismic code, will the sinking and leaning eventually take it out of code?
PhantomGremlin 10y ago
A building can have a tuned mass damper[1] to help counteract the swaying. You can even turn that into a tourist attraction of sorts.[2] [1] https://en.wikipedia.org/wiki/Tuned_mass_damper https://en.wikipedia.org/wiki/Tuned_mass_damper [2] https://www.youtube.com/watch?v=ohKqE_mwMmo https://www.youtube.com/watch?v=ohKqE_mwMmo
- wlesieutre 10y ago
  Taipei 101 even turned it into a mascot of sorts, the Damper Baby http://www.alamy.com/stock-photo-damper-baby-and-tuned-mass-damper-in-taipei-101-it-was-the-worlds-52580647.html http://www.alamy.com/stock-photo-damper-baby-and-tuned-mass-... http://josellesoh.deviantart.com/art/damper-baby-292759048 http://josellesoh.deviantart.com/art/damper-baby-292759048
ScottBurson 10y ago
I was asleep on about the 20th floor of a hotel in LA in 1992 when the 7.3 Landers and 6.5 Big Bear earthquakes hit [0]. The building (which I believe was on rollers) was rocking quite noticeably. I wasn't afraid for myself, though by the large, low-frequency motion I could tell it was a very large earthquake whose epicenter was a good distance away. I hoped it hadn't just taken out San Diego. Though I'll admit, to go back to sleep and then be wakened by a second large quake (Big Bear hit about 3 hours later; it is considered a separate quake rather than an aftershock) was starting to get a bit freaky. [0] https://en.wikipedia.org/wiki/1992_Landers_earthquake https://en.wikipedia.org/wiki/1992_Landers_earthquake [1] https://en.wikipedia.org/wiki/1992_Big_Bear_earthquake https://en.wikipedia.org/wiki/1992_Big_Bear_earthquake
- cgriswald 10y ago

raldi 10y ago

> It's leaning 6 inches so I'm assuming it's going to continue to lean further and further each year Why? Maybe it's settling into a new spot and the leaning will taper off. I think we need to wait and see what the experts say on this.

happyslobro 10y ago
Expert here! We need to wait and see if the angular velocity accelerates exponentially. Until then, we can't be certain that there is any hazard. You may all go back to work now. We'll measure its angle regularly and bill your insurance monthly until something or nothing happens.
BinaryIdiot 10y ago
Oh fair enough. That thought never crossed my mind. I kinda assumed if it starts leaning then gravity is only going to make it lean further. At least that's what it sounds like each time I read about it. But I don't know anything about structural engineering ¯\_(ツ)_/¯
- xenadu02 10y ago
  No one really knows; it's built on landfill that used to be part of the bay and it isn't anchored to bedrock. However the rate of movement will most likely continue to slow over time and the foundation that is present will keep it from falling over anytime soon. Think Leaning Tower of Pisa, which sank and tilted slowly over many years... long enough for corrective measure to be take. Fixing it will probably require cutting holes and driving down to bedrock, then pouring new concrete. It will have to be carefully done to avoid weakening the foundation and to make sure the new Piles don't poke through the concrete like a bed of nails. The developer cheaped out... using reinforced concrete is less expensive than steel but it makes the building a lot heavier. Why the city let them skip out on anchoring to bedrock for such a tall building in an earthquake zone I have no idea. I do find it hilarious that all the other big towers going up are happily advertising their bedrock pillar work.
  - repsilat 10y ago

pitaa 10y ago

You might be interested in the story of the Citicorp Center, a building in NYC that was dangerously susceptible to being literally blown over. >...LeMessurier calculated that a storm powerful enough to take out the building hits New York every 16 years. In other words, for every year Citicorp Center was standing, there was about a 1-in-16 chance that it would collapse.[0] [0] http://www.slate.com/blogs/the_eye/2014/04/17/the_citicorp_tower_design_flaw_that_could_have_wiped_out_the_skyscraper.html http://www.slate.com/blogs/the_eye/2014/04/17/the_citicorp_t...

m_mueller 10y ago
They didn't even give the student recognition, sleazy basterds. Should have given her a job right away!
kator 10y ago
During hurricane Sandy I lived directly across from the Chase building in the financial district. The motion of the Chase building made me sea sick looking at how much it swayed in the wind. You could see the window shades flying back and forth, some office chairs moving around. The displacement was obvious with the naked eye, it reminded me of palm trees at the beach during high winds.
- graaben 10y ago
  I worked in that building in 2012, and when we got back into the office later that week there were huge cracks running down the drywall from ceiling to floor.
- wdr1 10y ago
  Swaying is not necessarily indicative of a problem. The Sears Tower has a fair bit of sway as well. The general idea is "bend, don't break" and allow some give in high winds.