Rick Reuben wrote:( Of course, to illustrate this hypothesis, first Gramsci would need a video of a steel skyscraper 'collapsing' from fire, and since the only three examples of such videos were all made on 9/11/01, that limits the selection. )

"Melted" Steel"

Claim: "We have been lied to," announces the Web site AttackOnAmerica.net. "The first lie was that the load of fuel from the aircraft was the cause of structural failure. No kerosene fire can burn hot enough to melt steel." The posting is entitled "Proof Of Controlled Demolition At The WTC."

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.

But jet fuel wasn't the only thing burning, notes Forman Williams, a professor of engineering at the University of California, San Diego, and one of seven structural engineers and fire experts that PM consulted. He says that while the jet fuel was the catalyst for the WTC fires, the resulting inferno was intensified by the combustible material inside the buildings, including rugs, curtains, furniture and paper. NIST reports that pockets of fire hit 1832°F.

"The jet fuel was the ignition source," Williams tells PM. "It burned for maybe 10 minutes, and [the towers] were still standing in 10 minutes. It was the rest of the stuff burning afterward that was responsible for the heat transfer that eventually brought them down."

4. Weren't the puffs of smoke that were seen, as the collapse of each WTC tower starts, evidence of controlled demolition explosions?

No. As stated in Section 6.14.4 of NIST NCSTAR 1, the falling mass of the building compressed the air ahead of it—much like the action of a piston—forcing smoke and debris out the windows as the stories below failed sequentially.

These puffs were observed at many locations as the towers collapsed. In all cases, they had the appearance of jets of gas being pushed from the building through windows or between columns on the mechanical floors. Such jets are expected since the air inside the building is compressed as the tower falls and must flow somewhere as the pressure builds. It is significant that similar “puffs” were observed numerous times on the fire floors in both towers prior to their collapses, perhaps due to falling walls or portions of a floor. Puffs from WTC 1 were even observed when WTC 2 was struck by the aircraft. These observations confirm that even minor overpressures were transmitted through the towers and forced smoke and debris from the building.

Rick Reuben wrote:

gramsci wrote: no one apart from 9-11 cranks proposed the steel melted...

Something melted in those towers...what do you think it was,

meathead? Cough drops from someone's desk?

Rick Reuben wrote:

Gramsci wrote: NIST reports that pockets of fire hit 1832°F.

If NIST told Gramsci that the fires were hotter than the sun's core, Gramsci would accept it without blinking an eye. NIST's own reports never show temps hotter than 800 celsius around any core column.

Face it, you dunce. Skyscrapers are built out of steel because fire doesn't bring them down.

People standing right in the impact zone of WTC1:

How about those white-hot flames??

Rick Reuben wrote:

Rick Reuben wrote:Here's a photo of a controlled demolition, featuring demolition squibs firing in numerous places, off center, even before any pancaking has resulted:

But

Gramsci, you dope, why are there are all these photos of demolition squibs ejecting from known controlled demolitions, before any pancaking, if the cause is pancaking??? Your 'explanation' for these squibs is good comedy. Your faith in these liars is bottomless. No one is more faithful than you ( or more terrified of peer pressure...)

Squibs appear, no pancaking:
Not

WTC:

WTC:

WTC:

Pop, pop, pop go the squibs.