11-27-2010, 09:28 PM
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Too lazy to set a custom title
Industry Role:
Join Date: May 2004
Location: West Coast, Canada.
Posts: 10,217
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Quote:
Originally Posted by Alky
FEMA's official report said the jet fuel burned off within minutes.
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And as demonstrated, it only takes a few minutes for the steel to weaken and bend etc.
Quote:
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However, when bare steel reaches temperatures of 1,000 degrees Celsius, it softens and its strength reduces to roughly 10 percent 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.
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http://wtc.nist.gov/pubs/factsheets/faqs_8_2006.htm |
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