Did you read the NCSTAR 1-9 analysis of the location and extent of the fires? Did you find anything wrong with it?
Yes to both. I posted here https://www.metabunk.org/posts/41014
The fires are not sufficiently hot or long enough to cause the collapse... let alone a 'uniform, straight down, collapse'... What are the chances of that happening BTW... Any statatitions like to come up with an odds for random office fires in a massive building causing a uniform collapse similar to a demolition.
Content from external source:
"Paragraph/Sentence: Section 3.4.5 Second to last paragraph. “Figure 3-9 shows an example of the extent of structural damage from the fires, in this case for the 13th floor. At both 3.5 h and 4.0 h, connections, floor beams, and girders were damaged or had failed at steel temperatures that were approximately 400º C or less, primarily due to the effects of thermal expansion. After 4 h of heating, there was substantially more damage and failures in the WTC 7 structural system than at 3.5 h of heating.” And in the next paragraph: “However, it appeared likely the critical damage state occurred between 3.5 h and 4 h.”
(Cole) comment: Exact input details of the NIST model were not provided for review. However, based on the above, it appears the modeling effort to reach failure mode of the connections required was at least a time of 3.5 hours at a temperature of approximately 400º C., or to put it another way, any time less then 3.5 hours or 4 hours would not cause a failure.
Reason for Comment: Based on Figure 3.6, Page 30 (NCSTAR 1A) temperatures near the floor system of Column 79 did not sustain temperatures of 400º C for a time in excess of 3.5 hours. Rather, this indicated a time of perhaps 2 hours.
In addition, according to Page 330 Section 8.4.1 (NCSTAR 1-9 Vol. 1): “Prediction and growth of building contents fires (Chapter 9) indicated that such fires did not persist at any one location for more then about 20 min to 30 min., which is consistent with observations of fires in the windows (Chapter 5).”
Finally, Floors 12 and 13 (the SEC floors) were determined to be the hottest, yet: “Fire was first observed on the 12th floor, on the south side of the east face, at about 2:10 p.m.” (Page 381 NCSTAR 1-9 Vol 2), and didn’t even begin to heat up the areas near Column 79 until around 3:00 p.m.
NCSTAR 1-9 Page 243 for the 8th floor: “As late as 3:22 p.m., there was no indication of fire in this area but about 17 min later a substantial fire spreading to the east was visible between windows 8-47C and 8-53C.”
NCSTAR 1-9 Pages 244 and 245 state: 11th floor: “A fire was first observed at 2:08 p.m. on the east face.”, and for the 12th floor, a similar time.
For the 13th floor: “The first visual evidence for burning on the 13th floor was seen on the east face around 2:30 p.m.”; less then 3 hours before the collapse.
And even more importantly, the floor temperatures predicted (Figure 3-8 Page 31 NCSTA 1A) indicate temperatures colder then 200º C as late as 4:00 p.m. in the area of Column 79, and not until about 5:00 p.m. (20 minutes before collapse) does only a small portion of the floor area theoretically approach temperatures of 400 C. But the building collapsed at about 5:21 p.m. in the afternoon, about a half hour later, far less time than the critical 3.5 hour time used in the model.
If the entire analysis of the initial failure event is dependent on temperatures approaching 400º C that must exist over 3.5 hour period, and/or the fires did not last that long in the critical Column 79 area, then the entire foundation of the simulation appears flawed. And if the input of the model is flawed, the output results and conclusions are also flawed.
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