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My views on those that think the US government intentionally demolished the WTC complex should be very clear. I received an interesting comment today on one of my YouTube videos about thermal expansion:

NIST claims thermal expansion caused the collapse of WTC7 by the fires?

Is there anyway you could post a comment on whether the degrees of heat caused alot of thermal expansion. or just check the NIST’s report to see if they have any calculations For this?

They’ve allowed only 3 weeks to go through their documents to allow rebuttels and corrections. They call Thermal expansion of steel a “New phenomenon” which is weird when you have a video explaining thermal expansion a year prior

Obviously, this is in reference to the recent annoncement by NIST that progressive collapse brought about by weakened steel was the reason that the WTC7 building fell. I’ll respond as best I can.

Is there anyway you could post a comment on whether the degrees of heat caused alot of thermal expansion. or just check the NIST’s report to see if they have any calculations For this?

Yes. I am certain that thermal expansion occured and that it was probably significant. I am a materials scientist, though my research focus is on semiconductors and nanomaterials, so I have not personally studied anything to with the WTC in detail. However, the peer-reviewed research on the collapse of the Twin Towers points in this direction. I suggest starting with the following journal article:

“Behaviour of lightweight composite trusses in fire: A case study,” STEEL AND COMPOSITE STRUCTURES 7 (2): 105-118 APR 2007

Continuing …

They’ve allowed only 3 weeks to go through their documents to allow rebuttels and corrections.

This is merely for the report. The issue will still be argued and studied in the scientific and engineering community because it is incredibly interesting (see below).

They call Thermal expansion of steel a “New phenomenon” which is weird when you have a video explaining thermal expansion a year prior

The idea that materials expand and contract in response to thermal inputs is hardly new. My assumption is that what NIST means by “new phenomenon” is the thermal expansion of the steel trusses to the degree that allowed for collapse. This is new! There is truth to the 9/11 Troofer claim that before 9/11, no steel structure of the magnitude of the WTC buildings had ever fallen due to fire. The collapse of the three WTC buildings was unprecedented. If you would have asked an engineer before 9/11 if such a collapse scenario was possible, then they probably would have told you that it was very unlikely. That is precisely why the collapse has been studied in great detail by structural engineers and fire safety engineers and why there are numerous peer-reviewed articles in scholarly journals on this subject. In fact, the collapse has led to stricter building codes, as evidenced by the following article:

“Progressive collapse of structures: Annotated bibliography and comparison of codes and standards,” JOURNAL OF PERFORMANCE OF CONSTRUCTED FACILITIES 20 (4): 418-425 NOV 2006

I’m a little confused by NISTs recent report. I had assumed that this had always been their opinion on WTC7. Also, the claim that there were no “blast events” may be disingenuous, since there are credible reports that the fuel-oil tanks on the 3rd or 4th level (I can’t remember which level, precisely) had blown, which would not be suprising.