WTC7: Is AE911's (and NIST's) Focus on A2001 Justified if it Was Not "Key" in NIST's Global Model?


This thread is continuing right here, whether you’d like to continue participating in it or not. Your repeated conclusory assertions that NIST lied were moved to a rambles thread so they would not bog this thread down.

Continuing this thread—I noticed you deleted the claim you made last night re all elements of a composite floor system always moving in unison. Did you realize you were wrong and could not support that claim? Please clarify.
 
Please show where in Hulsey’s analysis he conclusively proved that the concrete deck and floor elements always move together in every direction uniformly, regardless of differences in local heating, and that differential heating of local systems would not, in fact, distort those systems differently as the NIST report clearly demonstrated in its simulation that actually properly heated localities differently, as was the case in the real life. I think you are making a wild claim that you cannot support. Hulsey doesn’t even try to prove such a ridiculous assertion.

You also didn’t respond re how Hulsey failed to model any connection failures.
Please show me where NIST says any of that would help prove A2001 was pushed off of its seat.
Also, your point about the local floor system being 400 degrees C at the time column 79 failed in NIST’s model just unwittingly demonstrates how off base Hulsey’s model is RE it’s temperature application.
Hulsey was misled, as many people were, by the preliminary analysis to get the shear studs to fail where NIST assumed 500 °C for the A2001 girder and 600 °C for the floor beams. It will be corrected in the final report. However, even at 600 °C, the floor beams could not expand enough to push the A2001 girder off of its seat.
A2001 was cooling when column 79 failed. The area to the west of column 79, meanwhile, was heating up.
Where does NIST say/show that?
 
This thread is continuing right here, whether you’d like to continue participating in it or not. Your repeated conclusory assertions that NIST lied were moved to a rambles thread so they would not bog this thread down.

Continuing this thread—I noticed you deleted the claim you made last night re all elements of a composite floor system always moving in unison. Did you realize you were wrong and could not support that claim? Please clarify.
No, I wanted to get Mick's reply first.
 
[moderator: off topic (and breaks link policy). response to off topic question removed.]



As for your question about the other end of A2001 possibly failing. It would have been trapped by the flange of column 44 so it could be pushed off.
Anything other than walk-off of A2001 at column 79 would invalidate the NIST hypothesis.
 
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Please show me where NIST says any of that would help prove A2001 was pushed off of its seat.

NIST NCSTAR 1-9 pg. 504, to be exact. Didn't you read the report by now? You can also see more on that exact point here in the main thread on the Hulsey report, which you also should have already have read at this point.

In sum, as I already told you in this thread, and as you should already know from the NIST report itself, A2001 failed in NIST's local model while column 79 was pushed to the east. NIST also expressly notes that composite floors failed and no longer acted as a composite system while this was happening.

Hulsey was misled, as many people were, by the preliminary analysis to get the shear studs to fail where NIST assumed 500 °C for the A2001 girder and 600 °C for the floor beams. It will be corrected in the final report. However, even at 600 °C, the floor beams could not expand enough to push the A2001 girder off of its seat.

Misled by whom? He couldn't competently read for himself the same report as the rest of us?

Where does NIST say/show that?

This was all covered in depth in the main thread on Hulsey's report. Did you not read that thread? Start here. Did you also not read and understand the NIST report on this point after all this time?

In sum, it is clear that the maximum temperatures Hulsey extracted from the NIST report for application in his own model were from after A2001 began to cool. All of NIST's temperature models show that A2001 had been much hotter an hour earlier in their simulation at 5:00pm than at the 6:00pm point in time when Hulsey extracted his temperatures.

We're now going in circles in what amounts to you trying to find new ways to deny the obvious: that Hulsey did not properly test the NIST scenario in a manner rigorous enough to rule it out. Your use of Hulsey's analysis to criticize NIST's focus on A2001 in its local model is thus entirely misplaced.

You cannot tell us that A2001 would not have walked off in Hulsey's model if Hulsey had properly modeled the fire progression, full extent of the fires, or cumulative local connection failures because Hulsey didn't do any of those things and so you don't know what would have happened if he did. You instead respond with hand-waving and ridiculous claims re the performance of composite flooring that are not supported by Hulsey or anyone else. You are literally making things up on the fly to support your argument at this point. That's not a useful way to discuss this topic. (In the past, you have taken a much more constructive approach to such discussions.)
 
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Didn't you read the report by now?
I have red the report and I had already saved the quote from the post on the main Hulsey thread.
A2001 failed in NIST's local model while column 79 was pushed to the east. NIST also expressly notes that composite floors failed and no longer acted as a composite system while this was happening.
The composite floors had failed in the southeast section, not the northeast section.
The compressive strains in the southeast area of the slab for Floor 12 gradually increased to exceed the crushing criterion (ε > 0.004) and covered the full east side and half of the south side of the tenant floor area. [of the southeast area] NCSTAR 1-9, Vol. 2, p. 505 [PDF p. 167/571]
Content from External Source
Misled by whom? He couldn't competently read for himself the same report as the rest of us?
I was misled by the preliminary analysis too as were most other people that I know of.
Hulsey extracted from the NIST report for application in his own model were from after A2001 began to cool.
The A2001 girder under floor 13 was the hottest at 6:00 p.m. (although the floor beams were the hottest at 5:00 p.m.)
1580264955662.png
Hulsey used 6:00 p.m., NIST's worst case scenario, to see what would really happen under those conditions.
I agree that he should have used 5:00 p.m. when the floor beams were hotter.
But how much difference would that make?
Table 10-1 tells us that the floor beams in the NE section of floor 13 did not exceed 600 °C.
1580268136649.png
The beam temp expansion vs sagging spreadsheet (below) tells us that at 600 °C., floor beam K3004 would expand lengthwise about 5-1/2 inches and sag about 5-1/2 inches. It would lose 1/8 inch to sagging for a net expansion of a little less than 5-1/2 inches.

However, NIST said that the A2001 girder walked off of its seat at less than 400 °C.
At temperatures less than approximately 400 °C, restrained thermal expansion of beams and girders caused axial compressive forces to develop in the beams and girders, which led to the following connection failures:
− bolt shear failure in fin, knife, and seated connections,
girder walk off of seated connections after all the bolts had sheared at Columns 79 and 81, and
− failure of header connection welds. NCSTAR 1-9, Vol. 2, p. 536 [PDF p. 198/602]
Content from External Source
At 400 °C, the K3004 floor beam would expand less that 3-1/2 inches.

In a errata, NIST admitted that their statement in the final report that 5-1/2 inches was needed to push A2001 off of its seat was wrong and it would take 6-1/4 inches. http://www.nist.gov/customcf/get_pdf.cfm?pub_id=901225

1580268521985.png

But all that is moot because the 12th floor graphic depicting slab temperatures in the east end of WTC 7: Figure 10-56 NCSTAR 1-9, Vol. 2, p. 449 [PDF p. 111]
and the 13th floor graphic depicting the beam and girder temperatures in the east end of WTC 7: Figure 10-59 NCSTAR 1-9, Vol. 2, p. 452 [PDF p. 114]
are wrong.

The fire on floor 12 had burned out on the east part of floor 12 by 3:45 p.m. so temperature of the 12th floor slab and the 13th floor beams and girders would be decreasing after that.
Fires for the range of combustible contents in WTC 7 ... persisted in any given location for approximately 20 min to 30 min. NCSTAR 1-9, Vol. 2, p. 617 [PDF p. 279/683]
Content from External Source
1580266759865.png
At 2:30 the fire on floor 12 was burning from the southeast corner to column 38.
The fire on floor 12 was first seen on the north face about 3:00 p.m. and by 3:10 (+or- 5 min.) it had spread to engulf the office at the NE corner and beyond column 46 on the north face. Therefore, by 3:45, the east end of floor 12 had been burned out.

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This thread is starting to veer off-topic. The topic is about the focus on A2001 walk-off, and it not being in the global model.

If you are going to post analyses, please ensure they pertain to the thread topic. If this starts to look like another endless 9/11 thread, then it will get shut down, or the digressers will be removed.

If you want to talk about if the walk-off was possible, then there's a thread for that here:
https://www.metabunk.org/threads/co...ve-got-past-the-side-plate-on-column-79.9069/
 
This thread is starting to veer off-topic. The topic is about the focus on A2001 walk-off, and it not being in the global model.

If you are going to post analyses, please ensure they pertain to the thread topic. If this starts to look like another endless 9/11 thread, then it will get shut down, or the digressers will be removed.

If you want to talk about if the walk-off was possible, then there's a thread for that here:
https://www.metabunk.org/threads/co...ve-got-past-the-side-plate-on-column-79.9069/
10-4 And thank you for the reference. I will post there.

I would like to revisit page 22 of the NIST report. (without the ad hominem attacks)

The text above the frame from the video simulation describes the walk-off hypothesis and ends with:
"This left column 79 with insufficient lateral support, and as a consequence, the column buckled eastward, becoming the initial local failure for collapse initiation."

That explicitly implies that the buckling of column 79 in the video simulation was due to the walk-off of A2001. So NIST did not have two hypothesis. The walk-off hypothesis and the video simulation are one and the same as far as NIST is concerned.

The fact that the video simulation does not show the walk-off is another matter, not another hypothesis. The suggestion that there were two hypotheses is just speculation.

The walk-off of A2001 is the key factor in the NIST hypothesis. It is the trigger that starts the collapse that brought down the building.
 
The walk-off hypothesis and the video simulation are one and the same as far as NIST is concerned.
are we talking about "as far as NIST is concerned?". I thought we were ignoring NISTs conclusions and just looking at what [limited] data we have from the report.


The fact that the video simulation does not show the walk-off is another matter, not another hypothesis. The suggestion that there were two hypotheses is just speculation.
if the video simulation shows something different, then there should have been 2 (at least) hypotheses... no?
 
are we talking about "as far as NIST is concerned?". I thought we were ignoring NISTs conclusions and just looking at what [limited] data we have from the report.
We are talking about the justification for the focus on the walk-off of A2001. Page 22 makes it clear that NIST focused on the walk-off as the key element and explicitly implied that the simulation shows the walk-off.
So AE911Truth and Hulsey are justified in focusing on the walk-off.
if the video simulation shows something different, then there should have been 2 (at least) hypotheses... no?
No. If there were two hypotheses, NIST would have said so but they didn't. Instead, they explicitly implied that the simulation shows the walk-off. i.e. one hypothesis
 
they explicitly implied
Sorry, I know I'm being pedantic here but this is a phrase you have used on at least three occasions.

One can either imply something or be explicit about it, but you can't have it both ways. Implicit and explicit are opposites, an explicit implication is an oxymoron, it cannot happen.

If someone is being explicit you can quote them on that point, implication on the other hand is not stated outright and thus can be more readily misinterpreted and may even only exist in the eye of the beholder. The use of the phrase "explicit implication" seems designed to give more weight to an opinion than it perhaps objectively deserves.
 
If there were two hypotheses, NIST would have said so but they didn't
I said "should have", I did not say they did.
Should NIST have looked into another theory considering the simulation does not show a walk off?

I dont care what they did do. Unlike you, i dont think NIST is infallible.

they explicitly implied that the simulation shows the walk-off.
no they didn't imply that. but not sure what that has to do with this topic anyway.
 
OK - Delineating the walk-off scenario to the point of column 79 buckling and then showing a frame from the video simulation that shows column 79 buckling, NIST is explicit that the video simulation includes the walk-off of A2001.

No. They are not explicit. You would need to write "I feel that they are implying that the walk off is in the simulation video".

But is there a reason you refuse to answer my actual question? Did you think I wouldn't notice you are trying to distract me (and thread readers) with off topic repetitive talking points?
 
if the video simulation shows something different, then there should have been 2 (at least) hypotheses... no?
No. If there were two hypotheses, NIST would have said so but they didn't. Instead, they explicitly implied that the simulation shows the walk-off. i.e. one hypothesis
I said "should have", I did not say they did.
Should NIST have looked into another theory considering the simulation does not show a walk off?
I understood you. If the simulation does not include the walk-off of A2001, then they should have dropped the walk-off hypothesis and formed a new hypothesis but they didn't or they would have said so.

They made it perfectly clear that they had no other hypothesis when they delineated the walk off hypothesis to the point where column 79 buckled and then included a frame from the video simulation showing column 79 buckling. That is being explicit.

explicit: stated clearly and in detail, leaving no room for confusion or doubt.

NIST stated the walk-off theory clearly and in detail, and left no doubt in the reader's mind that the frame from the video simulation was the result of the walk-off.
 
I understood you. If the simulation does not include the walk-off of A2001, then they should have dropped the walk-off hypothesis and formed a new hypothesis but they didn't or they would have said so.

They made it perfectly clear that they had no other hypothesis when they delineated the walk off hypothesis to the point where column 79 buckled and then included a frame from the video simulation showing column 79 buckling. That is being explicit.

explicit: stated clearly and in detail, leaving no room for confusion or doubt.

NIST stated the walk-off theory clearly and in detail, and left no doubt in the reader's mind that the frame from the video simulation was the result of the walk-off.

you are misunderstanding the question being discussed in this thread.
 
you are misunderstanding the question being discussed in this thread.
I understand the question. AE911Truth and Hulsey were justified in focusing on the A2001 girder walk-off because that is NIST's hypothesis, their only hypothesis. NIST may not have been justified but that is another matter.

There is no evidence to support the contention that NIST had, or might have had, a second hypothesis that they didn't reveal to the public. That's just baseless speculation.
 
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