Posted by Paul Dremann on September 13, 2002 at 14:38:35:
In Reply to: Re: The Price of Progress posted by d on September 13, 2002 at 11:49:18:
Thanks for your post.
Yes, I remember Ngon Nguyen. I'm sure he would remember our earlier posts on the days following the 9-11 disaster.
Yes there certainly was some of what you propose here. The 'actual' existing oxidation (at the moment of the collapse) may never be known or accurately quantified. Other circumstances were more culpable. The sudden weight'hammer effect of the jet collision...dead loads and explosive loads. Much more probable was the fire (very hot) acting on the soft (bumpers) of the then 'exposed' Viscoelastic dampers holding up every floor truss. The fireproofing was not working and as the metal deformed causing the rivits to shear at the truss chords leading to the weight of a section/most of a floor to land on the one below. Furthur down the building the dampers were all overloaded leading to shearing of the rivits and bolts.
The problem you posed about a 'hot fire' may/ may not do the same thing to the WTC tower. It would be (hypothetically) dangerous however. All that it would need to be a repeat would be that the fireproofing at the 'dampers' to become degraded, and deformation, to cause shear failure.
I would hope that investigators are 'all over' the Viscoelastic Damper problem. They have given themselves about 2 years to prove/disprove their part in the WTC collapse.
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