# Skyscrapers on fire, not collapsing **URL:** \ **Category:** Great Debates\ **Created:** [September 12, 2010, 10:53pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541 "2010-09-12T22:53:57Z")\ **Posts on this page:** 20\ **Page:** 27
**Author:** ![DrFidelius](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/drfidelius/32/3447_2.png) [@DrFidelius](https://boards.straightdope.com/u/DrFidelius)\ **Post date:** [September 28, 2010, 8:49pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/522 "2010-09-28T20:49:37Z")
> [@Mozart1220](#): > > > [@begbert2](#): > > > > Sixth’d (or whichever). This is an incredible if accidental display of how a tall structure composed mainly of rigid framework and air would collapse. > > > > I particularly liked how it survived the initial ‘plane’ hit (with minimal swaying! :p), only to be later felled when further damage (admittedly by a different kind of ‘fire’) caused the area to lose the remainder of its structural integrity. > > :D:D:D:D > > ETA: I _so_ want to see our resident truthers comment on that video. Not parodies of them, the actual people. > > It’s not a true test, since > > A: the structure was hollow > > B: it was “Lincoln logs” and you already pointed out how stupid I was for making that analogy. > > C: Not hit anywhere close to the place the planes hit. > > And that video could have been half as long, why did we need a slow motion shot of a miss? Don’t throw your back out moving those goalposts. You had the thought experiment of a very tall structure of Lincoln Logs, and you expected such a structure to topple instead of collapsing. These students built a very tall structure from a kit very similar to Lincoln Logs. When damaged, it collapsed, it did not topple. Therefore, your expectation that a very tall structure MUST topple is mistaken; that your assumption is erroneous is demonstrated by this model. When expectations do not match observed results, the intellectually honest person reexamines his expectations. ---
**Author:** ![Miller](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/miller/32/481_2.png) [@Miller](https://boards.straightdope.com/u/Miller)\ **Post date:** [September 28, 2010, 9:15pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/523 "2010-09-28T21:15:10Z")
> [@Contrapuntal](#): > > I just didn’t discuss it with you in that thread, and if I do say so myself I crushed you like a bug. Are you OK? You seemed to be off your game a bit. I’m just out of practice. It’s been so long since I haven’t had an argument with someone, my not arguing skills are rusty. ---
**Author:** ![yoyodyne](https://avatars.discourse-cdn.com/v4/letter/y/a9a28c/32.png) [@yoyodyne](https://boards.straightdope.com/u/yoyodyne)\ **Post date:** [September 28, 2010, 9:31pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/524 "2010-09-28T21:31:16Z")
> [@Mince](#): > > Also _listen_ to a few [controlled demolitions](http://weburbanist.com/2008/03/05/16-sweet-and-scary-building-demolitions-in-action/) and compare them to [building 7’s collapse](http://www.youtube.com/watch?v=LD06SAf0p9A). > > Wow! How many times does it need to be repeated that WTC 7 was _pulled down by wires_, not demolitions?! ---
**Author:** ![XT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/xt/32/456_2.png) [@XT](https://boards.straightdope.com/u/XT)\ **Post date:** [September 28, 2010, 9:34pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/525 "2010-09-28T21:34:33Z")
Are you sure about that? I thought it was held up by wires, and that someone cleverly cut said wires and that’s what brought down the tower (as an aside, it was done by Combat Wombats riding Battle Bunnies according to informed sources). -XT ---
**Author:** ![CurtC](https://avatars.discourse-cdn.com/v4/letter/c/ce73a5/32.png) [@CurtC](https://boards.straightdope.com/u/CurtC)\ **Post date:** [September 28, 2010, 9:40pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/526 "2010-09-28T21:40:27Z")
Yes, and when Silverstein said to “pull it,” he meant that he wanted the wires to be left in place, to continue pulling and holding the building up. It was all a very unfortunate misunderstanding. ---
**Author:** ![XT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/xt/32/456_2.png) [@XT](https://boards.straightdope.com/u/XT)\ **Post date:** [September 28, 2010, 10:01pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/527 "2010-09-28T22:01:53Z")
Huh…you see? You learn a lot in these threads. I had heard that Silverstein was sitting around with a bunch of his buddies in his Man Cave, and when he said ‘pull it’ he was referring to his finger so he could let off a ripper (apparently, according to inside sources, this always leaves them rolling in the isles, though if it’s from the humor or the smell is hard to determine). -XT ---
**Author:** ![pikey\_pete](https://avatars.discourse-cdn.com/v4/letter/p/8edcca/32.png) [@pikey\_pete](https://boards.straightdope.com/u/pikey_pete)\ **Post date:** [September 28, 2010, 10:42pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/528 "2010-09-28T22:42:01Z")
> [@yoyodyne](#): > > > [@Mince](#): > > > > Also _listen_ to a few [controlled demolitions](http://weburbanist.com/2008/03/05/16-sweet-and-scary-building-demolitions-in-action/) and compare them to [building 7’s collapse](http://www.youtube.com/watch?v=LD06SAf0p9A). > > > > Wow! > > How many times does it need to be repeated that WTC 7 was _pulled down by wires_, not demolitions?! you forgot about the wombats ---
**Author:** ![DrFidelius](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/drfidelius/32/3447_2.png) [@DrFidelius](https://boards.straightdope.com/u/DrFidelius)\ **Post date:** [September 28, 2010, 11:42pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/529 "2010-09-28T23:42:27Z")
Everybody forgets about the wombats. That’s the beauty of it all. ---
**Author:** ![Gorsnak](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gorsnak/32/7587_2.png) [@Gorsnak](https://boards.straightdope.com/u/Gorsnak)\ **Post date:** [September 29, 2010, 4:44am UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/530 "2010-09-29T04:44:01Z")
> [@Mozart1220](#): > > A: the structure was hollow Nearly all buildings are hollow, comprised mostly of air by volume. They aren’t really useful as buildings if they aren’t. The only exceptions I can think of are fortifications with massive solid walls, and special purpose structures such as the pyramids (which have demonstrated a marked resistance to collapsing). ---
**Author:** ![42fish](https://avatars.discourse-cdn.com/v4/letter/4/b487fb/32.png) [@42fish](https://boards.straightdope.com/u/42fish)\ **Post date:** [September 29, 2010, 2:08pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/531 "2010-09-29T14:08:28Z")
> [@begbert2](#): > > A: The WTC towers were hollow. Where do you suppose the people using the offices worked? Hanging off the outside the the building? So that’s why Silverstein had such a hard time renting it out! ---
**Author:** ![Sailboat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sailboat/32/461_2.png) [@Sailboat](https://boards.straightdope.com/u/Sailboat)\ **Post date:** [September 29, 2010, 4:11pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/532 "2010-09-29T16:11:28Z")
At random, I ran across a passage in a book about the Battle of Midway that has some bearing on fires and their well-known effect on structural steel. _Shattered Sword, the Untold Story of the Battle of Midway_, Parshall and Tully, page 299: > [@](#): > > The fires had been blazing on Akagi, Kaga, and Soryu for several hours now, and the ships were beginning to suffer permanent structural damage as a result. On board Akagi and Kaga, which each had an elevator that had been dropped into its well, the situation would have been aggravated, because the elevator shafts began acting like chimneys, venting smoke at the top and sucking air in through the bottom. The effect was to create a blast furnace. Steel structural members, having been heated too hot and for too long, were now glowing red and beginning to come apart under the strain. > [@](#): > > Inside, the bulkheads in the vicinity of the fires were now mostly bare, red-hot metal, the chalky, sodium-silicate fireproof paint having been either flaked off in handfuls by the explosions or scorched away by the flames. The aircraft in the hangars had long since been melted down to aluminum slag, leaving only the glowing steel engine blocks deposited on the hangar decks. ---
**Author:** ![Bryan\_Ekers](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bryan_ekers/32/183_2.png) [@Bryan\_Ekers](https://boards.straightdope.com/u/Bryan_Ekers)\ **Post date:** [September 29, 2010, 4:44pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/533 "2010-09-29T16:44:54Z")
> [@42fish](#): > > > [@begbert2](#): > > > > A: The WTC towers were hollow. Where do you suppose the people using the offices worked? Hanging off the outside the the building? > > So that’s why Silverstein had such a hard time renting it out! Huh. I’d’a thought balconies would be in demand in New York. ---
**Author:** ![Valgard](https://avatars.discourse-cdn.com/v4/letter/v/7feea3/32.png) [@Valgard](https://boards.straightdope.com/u/Valgard)\ **Post date:** [September 29, 2010, 4:45pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/534 "2010-09-29T16:45:29Z")
> [@Sailboat](#): > > At random, I ran across a passage in a book about the Battle of Midway that has some bearing on fires and their well-known effect on structural steel. > _Shattered Sword, the Untold Story of the Battle of Midway_, Parshall and Tully, page 299: > > > [@](#): > > > > The fires had been blazing on Akagi, Kaga, and Soryu for several hours now, and the ships were beginning to suffer permanent structural damage as a result. On board Akagi and Kaga, which each had an elevator that had been dropped into its well, the situation would have been aggravated, because the elevator shafts began acting like chimneys, venting smoke at the top and sucking air in through the bottom. The effect was to create a blast furnace. Steel structural members, having been heated too hot and for too long, were now glowing red and beginning to come apart under the strain. > > > [@](#): > > > > Inside, the bulkheads in the vicinity of the fires were now mostly bare, red-hot metal, the chalky, sodium-silicate fireproof paint having been either flaked off in handfuls by the explosions or scorched away by the flames. The aircraft in the hangars had long since been melted down to aluminum slag, leaving only the glowing steel engine blocks deposited on the hangar decks. Obviously, the Japanese were in on the conspiracy 60 years ago. I remember in some of the previous threads a couple of people (I think including **ivan astikov** or **psikeyhackr** ) trotting out the “It didn’t get hot enough for steel to melt” argument and then getting a blizzard of facts regarding how the yield strength of steel changes drastically at temps well below melting (50% loss at around 1000F, IIRC from my steel engineering courses), videos of steel foundries at work, etc. When the NIST report on WTC7 came out one of the CT posters referred to the “recently invented theory of thermal expansion”…evidently every blacksmith, barrel hooper and thermostat inventor throughout history has been in on the conspiracy as well. Frankly, I’m all for people asking about these things. Collapses like the WTC are so far removed from our everyday experience with “how stuff breaks” that it raises a lot of interesting questions and there’s the opportunity to educate people about some basic physics, engineering and so on. What bugs me are the people who absolutely refuse to learn anything - their question is answered, they raise it again, it’s answered again, they raise it again, they are referred back to many previous answers, etc… ---
**Author:** ![zut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zut/32/2875_2.png) [@zut](https://boards.straightdope.com/u/zut)\ **Post date:** [September 29, 2010, 6:02pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/535 "2010-09-29T18:02:30Z")
> [@Valgard](#): > > I remember in some of the previous threads a couple of people (I think including **ivan astikov** or **psikeyhackr** ) trotting out the “It didn’t get hot enough for steel to melt” argument and then getting a blizzard of facts regarding how the yield strength of steel changes drastically at temps well below melting (50% loss at around 1000F, IIRC from my steel engineering courses), videos of steel foundries at work, etc. Something I’d thought pertinent to this, but never gotten around to posting, is the relatively recent collapse of the Nine Mile Road bridge over I-75 here in Detroit. A gasoline tanker crashed and burned under the bridge, and the results have some parallel to the WTC disaster: fuel burning in the open air, thick black smoke, and the eventual collapse of the bridge (or, more exactly, the half of the bridge that had been heated) under the weight of the decking. For a quick visual ref, [here’s a seurity camera video of the start of the fire](http://www.youtube.com/watch?v=YJJghodxj4s&feature=related), [here’s more video as the fire rages](http://www.youtube.com/watch?v=iDCpFNiNcKg&feature=related), [here’s a news story](http://www.clickondetroit.com/news/20067687/detail.html), and [here’s a gallery of pictures from the aftermath](http://jalopnik.com/5316090/detroit-i+75-bridge-collapse-mega+gallery). Conclusion: steel + heat = bad ---
**Author:** ![XT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/xt/32/456_2.png) [@XT](https://boards.straightdope.com/u/XT)\ **Post date:** [September 29, 2010, 6:08pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/536 "2010-09-29T18:08:43Z")
_Scoff_ But everyone knows that bridges aren’t like skyscrapers. Plus, it’s not the same, since the bridge wasn’t hit by a plane first (which would have put out the fire, obviously). Also…how do you know that the government didn’t have the bridge wired to collapse in order to prove the 9/11 Official Story™?? (Need to book mark this thread and simply parrot it back the next time a Truther starts a similar thread…it’s got some very good links in it knocking down a number of the CT talking points) -XT ---
**Author:** ![Mozart1220](https://avatars.discourse-cdn.com/v4/letter/m/f1d935/32.png) [@Mozart1220](https://boards.straightdope.com/u/Mozart1220)\ **Post date:** [September 29, 2010, 6:10pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/537 "2010-09-29T18:10:59Z")
> [@Gorsnak](#): > > > [@Mozart1220](#): > > > > A: the structure was hollow > > Nearly all buildings are hollow, comprised mostly of air by volume. They aren’t really useful as buildings if they aren’t. The only exceptions I can think of are fortifications with massive solid walls, and special purpose structures such as the pyramids (which have demonstrated a marked resistance to collapsing). There were no beams, girders or floors in it at all? Wow. ---
**Author:** ![Valgard](https://avatars.discourse-cdn.com/v4/letter/v/7feea3/32.png) [@Valgard](https://boards.straightdope.com/u/Valgard)\ **Post date:** [September 29, 2010, 6:12pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/538 "2010-09-29T18:12:03Z")
> [@zut](#): > > Something I’d thought pertinent to this, but never gotten around to posting, is the relatively recent collapse of the Nine Mile Road bridge over I-75 here in Detroit. A gasoline tanker crashed and burned under the bridge, and the results have some parallel to the WTC disaster: fuel burning in the open air, thick black smoke, and the eventual collapse of the bridge (or, more exactly, the half of the bridge that had been heated) under the weight of the decking. For a quick visual ref, [here’s a seurity camera video of the start of the fire](http://www.youtube.com/watch?v=YJJghodxj4s&feature=related), [here’s more video as the fire rages](http://www.youtube.com/watch?v=iDCpFNiNcKg&feature=related), [here’s a news story](http://www.clickondetroit.com/news/20067687/detail.html), and [here’s a gallery of pictures from the aftermath](http://jalopnik.com/5316090/detroit-i+75-bridge-collapse-mega+gallery). Conclusion: steel + heat = bad The same thing happened here in the Bay Area in April 2007 when a gas tanker crashed and burned in the MacArthur maze (freeway interchange). The flames heated the steel structure of an overpass, it lost sufficient strength and collapsed onto the roadway below which played hell with traffic until it was rebuilt and the mess cleaned up. It took about one day for the CT folks to claim that this was a completely different situation than the WTC and thus no parallels could be drawn. ---
**Author:** ![Valgard](https://avatars.discourse-cdn.com/v4/letter/v/7feea3/32.png) [@Valgard](https://boards.straightdope.com/u/Valgard)\ **Post date:** [September 29, 2010, 6:14pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/539 "2010-09-29T18:14:07Z")
> [@Mozart1220](#): > > > [@Gorsnak](#): > > > > Nearly all buildings are hollow, comprised **mostly** of air by volume. They aren’t really useful as buildings if they aren’t. The only exceptions I can think of are fortifications with massive solid walls, and special purpose structures such as the pyramids (which have demonstrated a marked resistance to collapsing). > > There were no beams, girders or floors in it at all? Wow. Bolding mine. [http://dictionary.oed.com/cgi/entry/00316298?single=1&query\_type=word&queryword=mostly&first=1&max\_to\_show=10](http://dictionary.oed.com/cgi/entry/00316298?single=1&query_type=word&queryword=mostly&first=1&max_to_show=10) ---
**Author:** ![XT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/xt/32/456_2.png) [@XT](https://boards.straightdope.com/u/XT)\ **Post date:** [September 29, 2010, 6:15pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/540 "2010-09-29T18:15:34Z")
[QUOTE=Mozart1220] There were no beams, girders or floors in it at all? Wow. [/QUOTE] You said it…wow. Just…wow. -XT ---
**Author:** ![begbert2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/begbert2/32/3357_2.png) [@begbert2](https://boards.straightdope.com/u/begbert2)\ **Post date:** [September 29, 2010, 6:21pm UTC](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541/541 "2010-09-29T18:21:20Z")
> [@Mozart1220](#): > > > [@Gorsnak](#): > > > > Nearly all buildings are hollow, comprised mostly of air by volume. They aren’t really useful as buildings if they aren’t. The only exceptions I can think of are fortifications with massive solid walls, and special purpose structures such as the pyramids (which have demonstrated a marked resistance to collapsing). > > There were no beams, girders or floors in it at all? Wow. Putting aside your apparently poor grasp of the english language, what do you suppose you’re arguing here? The model that you’re tring to refute by claiming it’s hollow didn’t entirely lack internal ‘beams’ and ‘girders’ either; it had at _least_ two layers to its outer wall. And yet it still managed to collapse downward. I do realize that you’re not actually trying to construct a logical or coherent argument or position here, but could you at least try to maintain at least a _pretense_ that you’re addressing the actual discussion under discussion? [Previous page](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541.md?page=26) [Next page](https://boards.straightdope.com/t/skyscrapers-on-fire-not-collapsing/553541.md?page=28)