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> Tony wrote: > > jeff_wisnia wrote: > >> A more complete set of photos of this June's Shanghai building > >> collapse and diagrams explaining what happened and why.
> > I'm glad I don't live there, I'd never remember which apartment is > > mine, they all look alike, even the ones that are different look very > > similar. Well if the flat one was my building I suppose I could pick > > it out of the rest.
> > What is with the hollow pilings? They really look weak with a little > > bit of steel wire mesh in them. Hollow? Would it have happened if it > > were steel I beams encased in concrete?
> For the same amount of material, a tube is stronger than a solid cylinder.
Dig, dig, dig. The hollow piling is stronger for its intended load. The hollow tube piling has greater bearing capacity. The woulda/ coulda/shoulda Monday morning quarterbacking stuff is stupid. The excavation and the heavy rains are what caused the building to fall. Note the other buildings did not fall.
I know nothing of the seismic activity in the area, climate (read typhoon, etc), so it is pointless to speculate whether the design was adequate or not. If a contractor undermines a foundation, whatever the design, it will fail.
>I'm glad I don't live there, I'd never remember which apartment is mine, >they all look alike, even the ones that are different look very similar. > Well if the flat one was my building I suppose I could pick it out of >the rest.
>What is with the hollow pilings? They really look weak with a little >bit of steel wire mesh in them. Hollow? Would it have happened if it >were steel I beams encased in concrete?
It's a little hard to see in the photos but to me it looks like the pilings were actually made by first driving metal piles into the ground and then filling the inside of them and encasing the outside of them in concrete. most likely they drilled a hole to some depth, then dropped the piles in and drove them deeper, then backfilled it all with concrete with some rebar.
>> did you know 45,000 died last year in mining accidents?
> Citation please.
Actually, it was over twice that and that was a reduction...
> China’s State Administration of Work Safety said the coal mining > death toll fell 15% last year, dipping below 100,000 fatalities for > the first time in 14 years.
> The official death toll for 2008 was 91,172 fatalities while the > number of accidents dropped more than 10% to 506,000.
> Dig, dig, dig. The hollow piling is stronger for its intended load. > The hollow tube piling has greater bearing capacity. The woulda/ > coulda/shoulda Monday morning quarterbacking stuff is stupid. The > excavation and the heavy rains are what caused the building to fall. > Note the other buildings did not fall.
> I know nothing of the seismic activity in the area, climate (read > typhoon, etc), so it is pointless to speculate whether the design was > adequate or not. If a contractor undermines a foundation, whatever > the design, it will fail.
Certainly, that last was precisely the point I was made. The failure was of the nature it was because once the initial lean became of a certain magnitude the construction had little compensation for tension.
I still say seems at least moderately unusual to have so little steel in large concrete construction. I've not tried a typical design wind loading calculation estimate, but there would be quite a moment on those towers that would be translated downward on the windward side.
Ashton Crusher wrote: > On Sat, 07 Nov 2009 11:38:35 -0500, Tony <tony.mik...@gmail.com> > wrote:
>> jeff_wisnia wrote: >>> A more complete set of photos of this June's Shanghai building collapse >>> and diagrams explaining what happened and why.
>>> http://home.comcast.net/~jwisnia18/bldg_fall/ >> I'm glad I don't live there, I'd never remember which apartment is mine, >> they all look alike, even the ones that are different look very similar. >> Well if the flat one was my building I suppose I could pick it out of >> the rest.
>> What is with the hollow pilings? They really look weak with a little >> bit of steel wire mesh in them. Hollow? Would it have happened if it >> were steel I beams encased in concrete?
> It's a little hard to see in the photos but to me it looks like the > pilings were actually made by first driving metal piles into the > ground and then filling the inside of them and encasing the outside of > them in concrete. most likely they drilled a hole to some depth, then > dropped the piles in and drove them deeper, then backfilled it all > with concrete with some rebar.
I didn't see any rebar of any size at all anywhere in any of the pictures...
> Ashton Crusher wrote: > > On Sat, 07 Nov 2009 11:38:35 -0500, Tony <tony.mik...@gmail.com> > > wrote:
> >> jeff_wisnia wrote: > >>> A more complete set of photos of this June's Shanghai building collapse > >>> and diagrams explaining what happened and why.
> >>>http://home.comcast.net/~jwisnia18/bldg_fall/ > >> I'm glad I don't live there, I'd never remember which apartment is mine, > >> they all look alike, even the ones that are different look very similar. > >> Well if the flat one was my building I suppose I could pick it out of > >> the rest.
> >> What is with the hollow pilings? They really look weak with a little > >> bit of steel wire mesh in them. Hollow? Would it have happened if it > >> were steel I beams encased in concrete?
> > It's a little hard to see in the photos but to me it looks like the > > pilings were actually made by first driving metal piles into the > > ground and then filling the inside of them and encasing the outside of > > them in concrete. most likely they drilled a hole to some depth, then > > dropped the piles in and drove them deeper, then backfilled it all > > with concrete with some rebar.
> I didn't see any rebar of any size at all anywhere in any of the pictures...
"dpb" <n...@non.net> wrote: >>> did you know 45,000 died last year >>> in mining accidents?
>> Citation please.
> Actually, it was over twice that and > that was a reduction...
>> China’s State Administration of Work >> Safety said the coal mining >> death toll fell 15% last year, >> dipping below 100,000 fatalities for >> the first time in 14 years.
>> The official death toll for 2008 was >> 91,172 fatalities while the >> number of accidents dropped more than >> 10% to 506,000.
(Rest deleted)
I was the person seeking the citation, since those numbers seemed much too high for me. The citation provided did in fact support the very high number of deaths in China (~100,000 per year) in coal mining. I was still skeptical, and did a search on "coal mining deaths china" and found several sites that provided numbers much lower. Finally, I found one which said:
CORRECTION: 3,215 coal mining deaths in 2008
On January 28, China.org.cn carried a Xinhua story that mistakenly reported 91,172 deaths due to accidents in China's coal mines during 2008. The correct figure for 2008 coal mining deaths is 3,215, according to the State Administration of Work Safety (SAWS).
SAWS told China.org.cn today that a total of 3,215 people were killed in coal mining accidents in China during 2008, down from 3,786 in 2007.
A SAWS spokesperson said the 91,172 figure referred to the total number of deaths resulting from 413,752 accidents of all types throughout China during 2008. The figures include all workplace accidents as well as road traffic accidents. The corresponding figures for 2007 were 101,480 and 506,376. It is believed a mistake at a press conference led to the total accident figures being applied to coal mining alone.
The Chinese authorities acknowledge there is a major problem of health and safety in the country's coal mines, but say most accidents occur in small, privately-owned, and often illegal, mines rather than larger, state-owned producers. They also maintain that safety standards are gradually improving.
I can provide the links I read from the search I described above, but I suggest any other skeptics do a similar search of their own. I now believe the annual deaths in China from coal mining are in the 5,000-10,000 range, not approximately 100,000.
On Sun, 08 Nov 2009 07:42:50 -0600, dpb <n...@non.net> wrote: >Ashton Crusher wrote: >> On Sat, 07 Nov 2009 11:38:35 -0500, Tony <tony.mik...@gmail.com> >> wrote:
>>> jeff_wisnia wrote: >>>> A more complete set of photos of this June's Shanghai building collapse >>>> and diagrams explaining what happened and why.
>>>> http://home.comcast.net/~jwisnia18/bldg_fall/ >>> I'm glad I don't live there, I'd never remember which apartment is mine, >>> they all look alike, even the ones that are different look very similar. >>> Well if the flat one was my building I suppose I could pick it out of >>> the rest.
>>> What is with the hollow pilings? They really look weak with a little >>> bit of steel wire mesh in them. Hollow? Would it have happened if it >>> were steel I beams encased in concrete?
>> It's a little hard to see in the photos but to me it looks like the >> pilings were actually made by first driving metal piles into the >> ground and then filling the inside of them and encasing the outside of >> them in concrete. most likely they drilled a hole to some depth, then >> dropped the piles in and drove them deeper, then backfilled it all >> with concrete with some rebar.
>I didn't see any rebar of any size at all anywhere in any of the pictures...
There is some. Go to the very bottom picture, it's the best one for seeing the rebar and the steel pile. Upper left corner of the photo.
"EXT" <noem...@reply.in.this.group> wrote in news:4af4a115$0$65858 $892e0...@auth.newsreader.octanews.com:
> jeff_wisnia <jwis...@dumpthisconversent.net> wrote: >> A more complete set of photos of this June's Shanghai building >> collapse and diagrams explaining what happened and why.
> Those pilings look awfully flimsy, no wonder they snapped off, there was > hardly any re-rods and they were just hollow tubes, not much more than a > concrete drain pipe.
> > Sorry. I meant to agree with Robert, but my computer hiccupped. So, > > I guess I'll re-iterate (again) that it's amazing the building didn't > > crumble more.
> > I suspect that the reason it gives that appearance is because the > buildings > > collapse was cushioned a bit in the soft mud, allowing the stresses to > snap > > things sequentially as it fell rather than an explosion where the energy > is > > applied all at once.
> Yeah but . . . (-: Many of the windows didn't even break. That's just > bizarre. I wonder what the "rate of descent" was. I guess if it tipped over > gradually enough there wasn't a big slam at the end, but still, it's a > pretty amazing site. Or sight. Or even cite. Thanks for posting that, > Jeff.
> I guess I am used to seeing collapsed buildings in the aftermath of > earthquakes where the buildings fall because they are shaken apart. The > Shanghai building didn't have to endure any pre-collapse shaking and I am > betting the ground gave way slowly and the pilings appear to have bent > before they broke, asborbing both time and energy and moderating the forces > on the building. Still, what a ride that must have been. Sounds like a > project for Disney World. Here are some random EQ photos, FWIW:
re: "I guess if it tipped over gradually enough there wasn't a big slam at the end..."
Imagine being in the building at the time and feeling it slowly lean over. If it went over slow enough, you could just walk across the floor and step onto the wall, remaining upright the entire time.
As long as you could avoid the objects sliding across the floor with you, and the pictures and stuff falling from the opposite wall, it looks like you could have walked away from this type of collapse relatively unharmed.
Of course, getting to the door that was now on the ceiling could be tricky!
> > > Sorry. I meant to agree with Robert, but my computer hiccupped. So, > > > I guess I'll re-iterate (again) that it's amazing the building didn't > > > crumble more.
> > > I suspect that the reason it gives that appearance is because the > > buildings > > > collapse was cushioned a bit in the soft mud, allowing the stresses to > > snap > > > things sequentially as it fell rather than an explosion where the energy > > is > > > applied all at once.
> > Yeah but . . . (-: Many of the windows didn't even break. That's just > > bizarre. I wonder what the "rate of descent" was. I guess if it tipped over > > gradually enough there wasn't a big slam at the end, but still, it's a > > pretty amazing site. Or sight. Or even cite. Thanks for posting that, > > Jeff.
> > I guess I am used to seeing collapsed buildings in the aftermath of > > earthquakes where the buildings fall because they are shaken apart. The > > Shanghai building didn't have to endure any pre-collapse shaking and I am > > betting the ground gave way slowly and the pilings appear to have bent > > before they broke, asborbing both time and energy and moderating the forces > > on the building. Still, what a ride that must have been. Sounds like a > > project for Disney World. Here are some random EQ photos, FWIW:
> re: "I guess if it tipped over gradually enough there wasn't a big > slam at the end..."
> Imagine being in the building at the time and feeling it slowly lean > over. If it went over slow enough, you could just walk across the > floor and step onto the wall, remaining upright the entire time.
> As long as you could avoid the objects sliding across the floor with > you, and the pictures and stuff falling from the opposite wall, it > looks like you could have walked away from this type of collapse > relatively unharmed.
> Of course, getting to the door that was now on the ceiling could be > tricky!- Hide quoted text -
Ashton Crusher wrote: > On Sun, 08 Nov 2009 07:42:50 -0600, dpb <n...@non.net> wrote:
>> Ashton Crusher wrote: >>> On Sat, 07 Nov 2009 11:38:35 -0500, Tony <tony.mik...@gmail.com> >>> wrote:
>>>> jeff_wisnia wrote: >>>>> A more complete set of photos of this June's Shanghai building collapse >>>>> and diagrams explaining what happened and why.
>>>>> http://home.comcast.net/~jwisnia18/bldg_fall/ >>>> I'm glad I don't live there, I'd never remember which apartment is mine, >>>> they all look alike, even the ones that are different look very similar. >>>> Well if the flat one was my building I suppose I could pick it out of >>>> the rest.
>>>> What is with the hollow pilings? They really look weak with a little >>>> bit of steel wire mesh in them. Hollow? Would it have happened if it >>>> were steel I beams encased in concrete?
>>> It's a little hard to see in the photos but to me it looks like the >>> pilings were actually made by first driving metal piles into the >>> ground and then filling the inside of them and encasing the outside of >>> them in concrete. most likely they drilled a hole to some depth, then >>> dropped the piles in and drove them deeper, then backfilled it all >>> with concrete with some rebar. >> I didn't see any rebar of any size at all anywhere in any of the pictures...
> There is some. Go to the very bottom picture, it's the best one for > seeing the rebar and the steel pile. Upper left corner of the photo.
Evidently that one piece of rebar wasn't enough. ;-)
> > Sorry. I meant to agree with Robert, but my computer hiccupped. So, > > I guess I'll re-iterate (again) that it's amazing the building didn't > > crumble more.
> > I suspect that the reason it gives that appearance is because the > buildings > > collapse was cushioned a bit in the soft mud, allowing the stresses to > snap > > things sequentially as it fell rather than an explosion where the energy > is > > applied all at once.
> Yeah but . . . (-: Many of the windows didn't even break. That's just > bizarre. I wonder what the "rate of descent" was. I guess if it tipped over > gradually enough there wasn't a big slam at the end, but still, it's a > pretty amazing site. Or sight. Or even cite. Thanks for posting that, > Jeff.
> I guess I am used to seeing collapsed buildings in the aftermath of > earthquakes where the buildings fall because they are shaken apart. The > Shanghai building didn't have to endure any pre-collapse shaking and I am > betting the ground gave way slowly and the pilings appear to have bent > before they broke, asborbing both time and energy and moderating the forces > on the building. Still, what a ride that must have been. Sounds like a > project for Disney World. Here are some random EQ photos, FWIW:
re: "I guess if it tipped over gradually enough there wasn't a big slam at the end..."
<<Imagine being in the building at the time and feeling it slowly lean over. If it went over slow enough, you could just walk across the floor and step onto the wall, remaining upright the entire time.
As long as you could avoid the objects sliding across the floor with you, and the pictures and stuff falling from the opposite wall, it looks like you could have walked away from this type of collapse relatively unharmed.
Of course, getting to the door that was now on the ceiling could be tricky!>>
I thought about what a ride that must have been. It's a natural for Disney. (-:
> Ashton Crusher wrote: > > On Sun, 08 Nov 2009 07:42:50 -0600, dpb <n...@non.net> wrote:
> >> Ashton Crusher wrote: > >>> On Sat, 07 Nov 2009 11:38:35 -0500, Tony <tony.mik...@gmail.com> > >>> wrote:
> >>>> jeff_wisnia wrote: > >>>>> A more complete set of photos of this June's Shanghai building collapse > >>>>> and diagrams explaining what happened and why.
> >>>>> http://home.comcast.net/~jwisnia18/bldg_fall/ > >>>> I'm glad I don't live there, I'd never remember which apartment is mine, > >>>> they all look alike, even the ones that are different look very similar. > >>>> Well if the flat one was my building I suppose I could pick it out of > >>>> the rest.
> >>>> What is with the hollow pilings? They really look weak with a little > >>>> bit of steel wire mesh in them. Hollow? Would it have happened if it > >>>> were steel I beams encased in concrete?
> >>> It's a little hard to see in the photos but to me it looks like the > >>> pilings were actually made by first driving metal piles into the > >>> ground and then filling the inside of them and encasing the outside of > >>> them in concrete. most likely they drilled a hole to some depth, then > >>> dropped the piles in and drove them deeper, then backfilled it all > >>> with concrete with some rebar. > >> I didn't see any rebar of any size at all anywhere in any of the pictures...
> > There is some. Go to the very bottom picture, it's the best one for > > seeing the rebar and the steel pile. Upper left corner of the photo.
> Evidently that one piece of rebar wasn't enough. ;-)
If that was a NYC building, the foundation would be packed with dead mobsters instead of rebar. (-"
> > > Sorry. ?I meant to agree with Robert, but my computer hiccupped. ?So, > > > I guess I'll re-iterate (again) that it's amazing the building didn't > > > crumble more.
> > > I suspect that the reason it gives that appearance is because the > > buildings > > > collapse was cushioned a bit in the soft mud, allowing the stresses to > > snap > > > things sequentially as it fell rather than an explosion where the energy > > is > > > applied all at once.
> > Yeah but . . . (-: ?Many of the windows didn't even break. ?That's just > > bizarre. I wonder what the "rate of descent" was. ?I guess if it tipped over > > gradually enough there wasn't a big slam at the end, but still, it's a > > pretty amazing site. Or sight. ?Or even cite. ?Thanks for posting that, > > Jeff.
> > I guess I am used to seeing collapsed buildings in the aftermath of > > earthquakes where the buildings fall because they are shaken apart. ?The > > Shanghai building didn't have to endure any pre-collapse shaking and I am > > betting the ground gave way slowly and the pilings appear to have bent > > before they broke, asborbing both time and energy and moderating the forces > > on the building. ?Still, what a ride that must have been. ?Sounds like a > > project for Disney World. ?Here are some random EQ photos, FWIW:
> re: "I guess if it tipped over gradually enough there wasn't a big > slam at the end..."
> Imagine being in the building at the time and feeling it slowly lean > over. If it went over slow enough, you could just walk across the > floor and step onto the wall, remaining upright the entire time.
> As long as you could avoid the objects sliding across the floor with > you, and the pictures and stuff falling from the opposite wall, it > looks like you could have walked away from this type of collapse > relatively unharmed.
> Of course, getting to the door that was now on the ceiling could be > tricky!- Hide quoted text -
> - Show quoted text -
<Imagine walking thru that building TODAY.
it could be a tourist attraction:)>
I remember driving across the Verazzano Narrows Bridge in NYC during a very windy blizzard. I think that's the most scared I've every been. The bridge deck was icing over, tractor-trailers were rocking from side to side from the high wind and the bridge deck was shaking very hard.
Everbody in their cars had the hunkered down look you see on pictures of Civil War soldiers charging into a storm of bullets. Not one smile, hands clenched to the wheel, passengers all ashen-faced with fear. All I could think about was that famous film of the Tacoma Narrows Bridge breaking up in high winds. I was driving an Oldsmobile F-85 with rear wheel drive (I don't think very many cars had FrontWD back then) and it was fishtailing all over the road. The only way to drive was to make sure you had slow, but steady forward motion. If you stopped, you were going to spin on start up.
This was back when the VN bridge first opened, about 1964 or so, and there had not been a storm that bad so I figured I was a goner. What I worried about was whether I had clean underwear on and whether God would mind that I suddenly couldn't remember the words to the Lord's Prayer. Yes, the mind works in really weird ways. So I kind sort of imagine what a ride like that feels like. Sort of. (-: I'll bet, by some standards, the building would be less scary because it was over in seconds. My bridge ordeal took about an hour to cross a bridge that normally took 4 minutes.
> lol, with a little bracing, that coule be turned into another building just > as it sets! Imagine the room dimensions!
Architect I.M. Pei once said that we should reconsider our love of skyscrapers, particularly in earthquake zones because "Someday, the world's tallest building may end up being the world's longest one." I think he may be right if this is how they're being built.
"CWLee" <cdubya...@post.harvard.edu> wrote in message
<stuff snipped>
> I can provide the links I read from the > search I described above, but I suggest > any other skeptics do a similar search > of their own. I now believe the annual > deaths in China from coal mining are in > the 5,000-10,000 range, not > approximately 100,000.
> Best regards to all
Excellent catch, sir. I never failed to be amazed at how erroneous (and nearly unbelievable) information gains a monstrous life of its own on the Internet. Who hasn't done a Google search on a phrase in, say Wikipedia, only to find that 100 other sites have lifted the information? Sometimes it's verbatim, but sometimes is been subject to editing that subverts the original meaning, often with a nefarious agenda. My "favorite" (sarcasm alert) false numbers are war casualty statistics, loosely based on the "we lost no one, they lost everyone" theory.
I wonder, in this case, how much of the repetition of the outrageously highly initially quoted death toll is due to good faith transposition errors or a desire to believe that life is valueless, or near so, in China. Actually, what I think it says is that China is much, much larger than the US, so the numbers alarm us disproportionately, and that the Chinese are mining an enormous amount of coal. We had some pretty serious mine death figures in the US until we got serious about mine safety (the Feds, not the industry - they came along screaming ever inch of the way). This Mine Safety and Health Administration site
will show that the US and China have had some very parallel experiences when it comes to lots of miners dying yearly. Hopefully, they'll clean up their act as we did.
BTW, no offense meant to any posters here in this thread - I am sure no one falsified any statistics. It's just well known that if you take any group, from football teams to political parties to nations, there's SOMEONE that's got a bone to pick with them. Falsifying statistics is a time-honored way of doing that!)
>> lol, with a little bracing, that coule be turned into another building >just >> as it sets! Imagine the room dimensions!
>Architect I.M. Pei once said that we should reconsider our love of >skyscrapers, particularly in earthquake zones because "Someday, the world's >tallest building may end up being the world's longest one." I think he may >be right if this is how they're being built.
I remember a Monty Python episode where a building was held up by the belief of the residents that it was going to stay up. I guess these folks just didn't believe enough.
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