4 ms·

Any data on survivability of occupants of upper floors in cases where the bottom floor is destroyed and the rest of the building settles on top of the rubble in

by kijin 3y ago

Any data on survivability of occupants of upper floors in cases where the bottom floor is destroyed and the rest of the building settles on top of the rubble instead of pancaking? This is exactly what happened with some apartment blocks in Japan earlier this year, too. I guess it depends a lot on whether the building stays upright or falls over, as there are plenty of objects that can crush a person in any space that suddenly turns sideways.

bobthepanda 3y ago
Which is why the advice has always been to hide under something sturdy, like a table or bed. For the most part, it should break the impact of anything on top falling onto it.
- kijin 3y ago
  Yes, the usual advice is optimized for buildings that stay upright. But this [1] happens, too, surprisingly often with reinforced concrete buildings. A table turned sideways isn't going to stop the fridge that's hurtling toward you. Ships roll all the time in heavy seas but don't have the problem of loose fridges, because everything is anchored much more strongly than on land. Perhaps that's the kind of standard we should aim for, at least for concrete buildings in earthquake zones with a certain width to height ratio. [1] First photo in https://www.japantimes.co.jp/news/2024/01/02/japan/noto-peninsula-quake-damage/ https://www.japantimes.co.jp/news/2024/01/02/japan/noto-peni...
- rjzzleep 3y ago
  Table or bed? What they teach here locally is to get under a door frame or a pillar. I guess that recommendation has something to do with construction codes. When your walls are made out of light wood a sturdy table might protect you from fractured pieces I guess.
  - scoofy 3y ago
    If I remember from Introduction to Natural Disasters in college, the door frame example is mainly for masonry buildings, and is a bit of a historical artifact. My understanding is that advice today strongly suggests getting under something sturdy in the attempt to end up in a void during a collapse event.
    - rjzzleep 3y ago
      > My understanding is that advice today strongly suggests getting under something sturdy in the attempt to end up in a void during a collapse event. A table is sturdy? The doorframes here are made out of solid steel. It's literally the most sturdy place to be next to pillar. On top of that if the solid steel door gets stuck you will not leave the apartment until emergency services with steel drills or someone with welding equipment frees you from there. I'm a bit puzzled at what you were taught there. Contrary to the US, Taiwan has had proper earthquake compliant building codes that for the most part have been enforced(and reinforced) since the last disaster stuck the island over 20 years ago. For most places in the world outside of Japan, Taiwan, and a few other places an earthquake of this magnitude would be a mass casualty event.
      - bobthepanda 3y ago
        One is that in an open floor plan, you may not have time to find the nearest actual doorway. I would also imagine that the strength of any given doorway would depend on if the wall it was in is load bearing. A non load bearing wall is going to get crushed to bits once an actual load falls on it. I do think the advice is geared towards traditional furniture and not today’s IKEA particleboard crap.

by kijin 3y ago

bobthepanda 3y ago

Which is why the advice has always been to hide under something sturdy, like a table or bed. For the most part, it should break the impact of anything on top falling onto it.

kijin 3y ago
Yes, the usual advice is optimized for buildings that stay upright. But this [1] happens, too, surprisingly often with reinforced concrete buildings. A table turned sideways isn't going to stop the fridge that's hurtling toward you. Ships roll all the time in heavy seas but don't have the problem of loose fridges, because everything is anchored much more strongly than on land. Perhaps that's the kind of standard we should aim for, at least for concrete buildings in earthquake zones with a certain width to height ratio. [1] First photo in https://www.japantimes.co.jp/news/2024/01/02/japan/noto-peninsula-quake-damage/ https://www.japantimes.co.jp/news/2024/01/02/japan/noto-peni...
rjzzleep 3y ago
Table or bed? What they teach here locally is to get under a door frame or a pillar. I guess that recommendation has something to do with construction codes. When your walls are made out of light wood a sturdy table might protect you from fractured pieces I guess.
- scoofy 3y ago
  If I remember from Introduction to Natural Disasters in college, the door frame example is mainly for masonry buildings, and is a bit of a historical artifact. My understanding is that advice today strongly suggests getting under something sturdy in the attempt to end up in a void during a collapse event.
  - rjzzleep 3y ago
    > My understanding is that advice today strongly suggests getting under something sturdy in the attempt to end up in a void during a collapse event. A table is sturdy? The doorframes here are made out of solid steel. It's literally the most sturdy place to be next to pillar. On top of that if the solid steel door gets stuck you will not leave the apartment until emergency services with steel drills or someone with welding equipment frees you from there. I'm a bit puzzled at what you were taught there. Contrary to the US, Taiwan has had proper earthquake compliant building codes that for the most part have been enforced(and reinforced) since the last disaster stuck the island over 20 years ago. For most places in the world outside of Japan, Taiwan, and a few other places an earthquake of this magnitude would be a mass casualty event.
    - bobthepanda 3y ago
      One is that in an open floor plan, you may not have time to find the nearest actual doorway. I would also imagine that the strength of any given doorway would depend on if the wall it was in is load bearing. A non load bearing wall is going to get crushed to bits once an actual load falls on it. I do think the advice is geared towards traditional furniture and not today’s IKEA particleboard crap.