The fireproofing that protects the steel is meant to protect it for 2 hours, not 7.

These questions have all been answered, but you conspiracy people are as bad as the fanatically religious; just keep plugging your ears and yelling, "la la la la, I can't hear you!"
>> ^Fade:

Do they perhaps use some kind of special fireproofing that protects steel from fire in skyscrapers? I mean they did claim that the planes blew this fireproofing off the twin towers thus exposing the steel. This didn't happen for wtc7.

was the wtc7 fire somehow magically hotter than all the other skyscraper fires that never resulted in a collapse?
Do they perhaps use some kind of special fireproofing that protects steel from fire in skyscrapers? I mean they did claim that the planes blew this fireproofing off the twin towers thus exposing the steel. This didn't happen for wtc7.

Why didn't this building collapse?

http://www.youtube.com/watch?v=nH5-DpMObGc

or this one?

http://youtu.be/j4MjsVnasLA

You clearly don't understand structural engineering so I seriously doubt you would have a firm grasp of rocket science.
>> ^Skeeve:

According to the American Institute of Steel Construction, "Steel loses about 50 percent of its strength at 1100°F, and at 1800°F it is probably less than 10 percent." This is in addition to the expansion of the steel due to the heat (which is great enough to crack any concrete it is reinforcing). A 20' beam will expand 1.5 inches at 1000 degrees.
So, even if we assume the fire wasn't even as hot as your average house fire, you now have cracked and broken concrete and steel beams that are warping and bending. And, just like a pop can (or a paperclip, or any thing else really) once something has started to bend, bending it further just gets easier.
This isn't exactly rocket science.
>> ^Fade:
I believe when architects are designing concrete high-rises the requirement is for the structural steel to be able to support 3 to 5 times the maximum load that will ever be applied to it during its lifetime. Thus a 'theoretical' (since we have no way of knowing what temperature was actually in place) 50% weakening in the strength of the steel cannot result in a complete failure of all the support column at exactly the same time.
>> ^Skeeve:
A house fire can reach 1500 degrees in 3 1/2 minutes but an office fire can't reach the 1000 degrees necessary to bring steel to 50% of it's strength? Bullshit.
>> ^marinara:
I really doubt that a failure of a steel beam, which supports the floor (and nothing else), could take down an entire building.
Otherwise the facts in this video are generally correct, but misleading. (because office fires don't burn over 1000 degrees)

Exactly how does some office furniture burn for 7 hours, and then raise (fireproofed) steel to over 1000 degrees? What we know from other videos of WT7, is many of the fires extinguished themselves (burned themselves out).


I really doubt that a failure of a steel beam, which supports the floor (and nothing else), could take down an entire building.

Otherwise the facts in this video are generally correct, but misleading. (because office fires don't burn over 1000 degrees)

I'm saying they tested for scenarios such as jets with full fuel loads smashing into the towers when they designed them. And provided quotes from the actual engineers stating that fact.

Some questions, since I always manage to completely misunderstand waht you believe your saying:

Most importantly, do you trust the honesty and competence of the engineers who published those tests?
I for one do.

Do you realize that your quotes from those engineers are from long BEFORE the attacks on the towers?

Do you realize that NONE of those engineers have come forward to condemn or rebuke the official story of the collapse?

The deeper story of the references you've given is that the engineers behind them have new evidence since the attacks. Primarily that the buildings collapsed hours after being hit by airliners. They have accepted a re-analysis of their initial tests and agree with the conclusion. That the combination of the initial crash striping the fireproofing and the following fires could collapse the towers, a condition they did not test for in their initial analysis you referenced.

And the number one question still stands:

Where is the profit in crashing the planes into the buildings, that wasn't already equally profitable by simple controlled demolition.

true westy ... designing for the worst case scenario would involve controlling all the variables... ut the buildings werent designed to fail at all, much less designed to fail in a specific manner which then happened to play out... but if the building wasnt as fireproof/structurally sound as it SHOULD have been...

its hard to judge the theoretical results vs the actual results... obviously the building fell down... would it have fallen down as easily in other scenarios? thats scary too, although out of control fires are destructive.


consider the building in spain that burned almost to its frame without collapsing..i read the steel frame was wrapped in concrete, and that should have made the steel even hotter than WT7.. but Windsor didnt fall ... so... it pays to know your building materials and have contingency and a little luck..

maybe the WT7 building was just built poorly and no one knew, like maybe the project was being ripped off by the .. i dunno, sopranos (mob)? theres always more than meets the eye

http://www.youtube.com/watch?v=j4MjsVnasLA

For reference...

NIST report and press conference:
Sunder said that his team investigated these hypothetical causes [thermite] and ruled them out. "We asked ourselves what is the minimum amount of charge we could use to bring the building down," he said. "And we found that even the smallest charge would release an extremely loud sound heard half a mile away." There were no reports of such a sound; numerous observers and video recordings found the collapse to be relatively quiet.

FEMA:
The eutectic temperature for this mixture strongly suggests that the temperatures in this region of the steel beam approached 1,000 degrees C (1,800 degrees F), which is substantially lower than would be expected for melting this steel...

FEMA:
Temperatures in this region of the steel were likely to be in the range of 700 to 800 degrees C (1290 - 1470 degrees F).

NIST:
In no instance did NIST report that steel in the WTC towers melted due to the fires. The melting point of steel is about 1,500 degrees Celsius (2,800 degrees Fahrenheit). Normal building fires and hydrocarbon (e.g., jet fuel) fires generate temperatures up to about 1,100 degrees Celsius (2,000 degrees Fahrenheit). NIST reported maximum upper layer air temperatures of about 1,000 degrees Celsius (1,800 degrees Fahrenheit) in the WTC towers (for example, see NCSTAR 1, Figure 6-36).
However, when bare steel reaches temperatures of 1,000 degrees Celsius, it softens and its strength reduces to roughly 10 percent [***NOTE: no reference] of its room temperature value. Steel that is unprotected (e.g., if the fireproofing is dislodged) can reach the air temperature within the time period that the fires burned within the towers. Thus, yielding and buckling of the steel members (floor trusses, beams, and both core and exterior columns) with missing fireproofing were expected under the fire intensity and duration determined by NIST for the WTC towers.

Modulus of Elasticity for Steel:
http://www.engineeringtoolbox.com/young-modulus-d_773.html

What is concerning is that thermite was rule out because of the noise, and that 1000 lbs would be needed.

Also, no one has explained the UL testing on the steel for 6 hrs at 1000C?

Finally, what is troubling is that softening girders causeing collapse, fine, steel is weakened at 1400degF, but the core wouldn't fall. Certainly wouldn't break apart.

I hope they'll make it fireproof this time.

>> ^quantumushroom:
TLF = Typical Liberal Fascism.

Liberal fascism makes about as much sense as fireproof matches?

From your own link:

FACT: Jet fuel burns at 800° to 1500°F, not hot enough to melt steel (2750°F). However, experts agree that for the towers to collapse, their steel frames didn't need to melt, they just had to lose some of their structural strength — and that required exposure to much less heat. "I have never seen melted steel in a building fire," says retired New York deputy fire chief Vincent Dunn, author of The Collapse Of Burning Buildings: A Guide To Fireground Safety. "But I've seen a lot of twisted, warped, bent and sagging steel. What happens is that the steel tries to expand at both ends, but when it can no longer expand, it sags and the surrounding concrete cracks."

"Steel loses about 50 percent of its strength at 1100°F," notes senior engineer Farid Alfawak-hiri of the American Institute of Steel Construction. "And at 1800° it is probably at less than 10 percent." NIST also believes that a great deal of the spray-on fireproofing insulation was likely knocked off the steel beams that were in the path of the crashing jets, leaving the metal more vulnerable to the heat.

The Madrid fire burned for 24 hours at temperatures up to 800°C (1500°F) and did not collapse. In 2004, Venezuela's tallest building burned uncontrolled for 17 hours and did not collapse. WTC7 had two small fires which burned for 6 hours and it collapsed in what looks like a controlled demolition.


When the tapes from 9/11 firefighters in were released, there was no mention of communication problems as we were told, and firefighters only reported small pockets of fire, not a huge inferno that can melt steel.

Two hose lines are needed, Chief Orio Palmer says from an upper floor of the badly damaged south tower at the World Trade Center. Just two hose lines to attack two isolated pockets of fire. ''We should be able to knock it down with two lines,'' he tells the firefighters of Ladder Company 15 who were following him up the stairs of the doomed tower.

Lt. Joseph G. Leavey is heard responding: ''Orio, we're on 78, but we're in the B stairway. Trapped in here. We got to put some fire out to get to you.''

Ladder 15 had finally found the fire after an arduous climb to the 78th floor, according to the tape. They were in the B stairwell. On the other side of the fire were hundreds of people, blocked from fleeing by smoke and flame on the stairs. Chief Palmer was facing similar fires in the A stairwell, across the floor.

''We're gonna knock down some fire here in the B Stair,'' Lieutenant Leavey is heard telling one of his firefighters. ''We'll meet up with you. You get over to the A Stair and help out Chief Palmer.''

If those fires were burning at 1500-1800°F, the people on that floor would have been dead.

I'm no conspiracy theory nutcase, but I'm also not stupid, the "official" explanations of collapse just don't match reality.

Actually, if a straw-bale house is properly built and maintained, there shouldn't be an issue with decomposition -- they can easily last as long as a conventionally-built house. They cost around the same to build, yet are incredibly energy-efficient, are made from non-offgassing materials, and are impressively fireproof.

I know somebody who built a huge straw-bale home near where I live in Ontario, which gets pretty cold winters, usually averaging -15°C to -20°C. Construction was completed in the fall, and because he was still researching alternative heating options for the house, he hadn't installed a heat source by the time winter hit. He discovered that a small space heater in the living room was enough to heat the whole house.

At least in my part of the world, there doesn't seem to be any trouble getting building permission or insurance for straw bale houses. I've heard that they are even more widespread in the USA than here. As more get built, the building techniques will continue to improve and the costs will inevitably come down further as well.

Thanks for the video, Mink! I'm in total support of green living options.

Secondly, evidently, you're under the impression that the National Institute of Standards and Technology have it all wrong. We have already seen that fire can appreciably affect structural steel and bring about a global collapse; we have also seen that the fireproofing was either damaged or insufficient to withstand fires of the requisite duration. So, please explain to me, in structural engineering (or even more prosaic) terms, the ways in which the buildings were "capable of withstanding the damage that they sustained." Further, you claim that "When one floor collapses upon the other, it does not gain speed - it loses speed"; please explain to me, in terms of the principles of the conservation of momentum, acceleration due to gravity, and those of elastic and inelastic collisions, how you have arrived at this conclusion.

Thirdly, please provide some evidence of "ground-level explosions".

Lastly, please provide some evidence to substantiate your belief that "The Bush administration, with a lot of help from Giuliani, went out of their way to conceal and destroy the evidence"; if you have no such evidence, then please explain the ways in which it is rational to hold this belief.

There is no mystery concerning the fireproofing. In the cases of World Trade Center buildings 1 and 2, the fireproofing was a light and brittle composite which had been simply sprayed-on to the structural steel; that steel was thrashed and the fireproofing stripped by the debris and explosions caused by the impacts of the airliners. In the case of World Trade Center 7, the fireproofing was designed to withstand, at most, a three-hour fire; on 9/11, however, World Trade Center 7 burned for approximately eight hours.

You have patently misrepresented my views on the issue of the molten metal and in doing so have committed the straw man logical fallacy. Clearly and straightforwardly, I neither claimed nor implied that the photographs of molten metal had been faked. Here is what I did say: "There is no compelling evidence of molten steel; the molten metal was mostly likely aluminium".

Perhaps some of your incredulity stems from the fact that you evidently haven't properly understood the National Institute of Standards and Technology's conclusions concerning the collapse mechanism; they simply do not state that global failure was brought about by the catastrophic collapse of the floor slabs.

Par. Let's take just one question instead of sidestepping around straw.

Let's say, for argument's sake, that a 767 is significantly bigger than a 707, that enough fuel remained in the building to burn enough to weaken the floors, that the visible molten metal was a freak occurrence and/or photoshop conspiracy theory, that somehow fireproofing was blown away all over the place over many floors even half a block away from the impact, and that the floors then distorted and collapsed catastrophically, due to the design of the building and the weak connections between the wall and the floor.

OK? I am agreeing with you so far.

Now, explain to me how the core, an enormous treetrunk of steel and concrete, collapsed also, completely, into dust, at the same time as all the floors, which had just disconnected from the core in order to fall, and were so flimsy that they couldn't drag the core down with them. I will even let you assume that somehow the floors disconnected evenly and simultaneously, permitting a total collapse into pretty much the footprint of the building.

How did the core collapse and turn to dust? Where did the energy come from for that? Just explain this, and I will instantly switch to your side of the argument and call choggie a weirdo conspiracy theorist.

I honestly would like to believe it man, it's just, you haven't addressed any of the issues that concern me, you've just debunked things i already find weak, and added things like "don't you trust NIST?" which make me think you might be gullible, or proud of you rational "non conspiracy theorist" position.

I would have an easier time believing the government on this one if they had done a better job of investigating the scene. If it is so obvious that there is no conspiracy, then I have to ask the question: Why not investigate the fuck out of this thing, out in the open? Families of victims still don't have satisfaction.

Then I remember the hundreds of other lies from Bush et al and I find it difficult to trust them on this one.

Please at least empathise with us skeptics, we have all been lied to a LOT, and it seems only rational to take a skeptical position in the absence of satisfactory explanation.

How did that core collapse like that?

The McCormick example serves to illustrate that fire can significantly affect structural steel and ultimately bring about a global collapse. The World Trade Center buildings had sprinkler systems and fireproofing -- both of which were stripped and destroyed by the impact of the airliner.

The sites of planes crashes, building collapses and suchlike are routinely cordoned-off and assigned to investigators for very obvious reasons. There is nothing suspicious about that.

"fantasist nonsense"-nice label

THE MC CORMICK
NOTHING LIKE A SKYSCRAPER
The gleaming white building burned down in 1967, a shocking event as it was largely steel and concrete and was thought to be fireproof. However, the exhibits at the time were highly flammable and there were inadequate sprinklers and hydrants, thus the fire spread quickly and destructively, taking the life of a security guard in the process.-some wiki-blogger

trade center had a completely different set of elements..fire-proofing, sprinklers, redundant columns for support...

the "evidence" at the site??? The site having been cordoned off and assigned investigators, means most evidence they produced in the form of reports should be held up to scrutiny, and remains suspect, doesn't it follow, that of you stack deck, you will win the pot???