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2006-09-19 09:53:57 · 12 answers · asked by Anonymous in Science & Mathematics ➔ Engineering
It happens more than people realize.
In Paraguay on August 1st, 2004 a fire burned out of ductwork that had not been properly cleaned and ignited a fire above the ceiling in a two story shopping center with a parking deck. The fire burned above the ceiling, unoticed and eventually weakened the steel supports and the building's roof collasped. 417 Perished.
Obviously, everyone is aware of the WTC collapses. I think that's probably the first time it happened on that large a scale and that publicly. The WTC fire is constantly compared to other high rise fires such as the One Meridian Plaza Fire in Philadelphia or the First Interstate Bank fire in L.A. But there is one missing component that often is not talked about. The sprinkler systems in these other fires stayed functional and kept the steel frame cool enough to withstand the fire.
Fire weakens steel, that's why we treat the steel with protective coatings and install water sprinkler systems. In the case of the WTC, these systems were compromised.
I ran with fire and rescue in a SMALL community for about 4 years and personally saw two fires in smaller facilities (steel frame) that were not large enough to merit fire sprinklers. The roof and steel trusses gave way in both of those fires.
Firefighters die every year from truss related failures, both wood AND steel, I'll admit more from wood. Check out this quote from third link below...
"More than 60% of the roof systems in the United States are built using a truss system. By design, wooden truss systems contain a significant fuel load and are often hidden from sight. Fires in truss systems can burn for long periods before detection and can spread quickly across or through the trusses. Steel trusses are also prone to failure under fire conditions and may fail in less time than a wooden truss under the same conditions."
Probably not the answer you were looking for. Be careful of the truth, it may surprise you when you least expect it.
2006-09-20 04:34:42 · answer #1 · answered by todvango 6 · 2⤊ 0⤋
Almost every that has any amount of fuel inside to burn. Steel doesn't have to reach the melting point to become weakened by the heat.
We just had a fire in our building and part of the requirement to get a building permit to make the repair required that we have a structural engineer inspect the steel frame and recommend repairs.
The fire lasted only a few minutes and only burned some wooden parts of the building. The sheet metal roof and wall decks were destroyed (light guage metal) Steel trusses near the point of ignition were warped and misshaped by the heat and will have to be reinforced before the building can be occupied. Had the fire lasted another 30 minutes the single story structure would have collasped under its own weight. Just imagine what would have happened if it had 40 stories of concrete and steel sitting on top of it.
2006-09-19 15:09:30 · answer #2 · answered by Roadkill 6 · 1⤊ 0⤋
Steel frame buildings usually do fall down if the rest of the building is on fire and the heat of the fire gets hot enough to bend the steel. This would cause the building to collapse. I do know of a few that have fallen down because of this. Just because you have a steel frame doesnt mean the rest of the building wont catch fire as the other materials used to line the walls can be flammable.
2006-09-19 09:58:23 · answer #3 · answered by auburn 7 · 1⤊ 0⤋
Numerous. However building WTC 7, I assume was splashed with jet fuel when the jets hit, and considering jet fuel burns EXTREMELY HOT!!!!, I assume that bent the steel muuuucccchhhhh faster than any regular fire would have. And don't lead this conversation into some stupid conspiracy theory that the government was involved, because the government made bookoo dollars off the WTC.
2006-09-19 11:02:12 · answer #4 · answered by The Crow 3 · 1⤊ 0⤋
How many steel framed buildings have been soaked with jet fuel?
2006-09-19 09:56:19 · answer #5 · answered by Anonymous · 1⤊ 0⤋
How many idiots actually could believe our own government was involved in 911. Cause I know exactly where this arguement is headed. Go back to your parents' basement, and leave your ridiculous ideas to yourself.
2006-09-19 10:08:56 · answer #6 · answered by AresIV 4 · 1⤊ 0⤋
That would be a tough question..but metal gets weak under heat...it really depends on the fire load.
2006-09-19 09:56:59 · answer #7 · answered by ? 6 · 1⤊ 0⤋
Apparently just the one...Building 7
2006-09-19 09:55:21 · answer #8 · answered by eantaelor 4 · 0⤊ 1⤋
Last time I counted it was 20
2006-09-23 03:21:23 · answer #9 · answered by Anonymous · 0⤊ 0⤋
many
2006-09-19 09:55:43 · answer #10 · answered by ted k 2 · 2⤊ 0⤋