Quote:
Originally Posted by SwordNboard
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The WTC could have burned all year long and the steel would've stayed standing.
..but somehow, it collapsed in a day. From burning at the top..
Mmmkay.
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[Professor of Structural Engineering at the University of Newcastle, John Knapton] told BBC News Online: "The world trade centre was designed to withstand the impact of a Boeing 707, but that was unusual... we are trying to discover why they [ the towers ] collapsed and what needs doing to rebuild them."
"The buildings survived the impact and the explosion but not the fire, and that is the problem."
"The 35 tonnes of aviation fuel will have melted the steel... all that can be done is to place fire resistant material around the steel and delay the collapse by keeping the steel cool for longer
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 800º to 1500ºF, not hot enough to melt steel (2750ºF). 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."