AE911 Truth's WTC7 Evaluation Computer Modelling Project

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As we near the release of Hulsey's draft, I would urge you/them to interrogate his computer models, and yes, reject any unsupported claims, but also accept what is substantiated. NIST's omissions and mistakes line up to increase the girder's movement relative to column 79, taking it to precisely the minimum displacement necessary to initiate the putative buckling sequence for that column. Hulsey shows that correcting these errors reduces the movement to a third of that. As far as I can see, no one has really disputed that. The disputes are over whether Hulsey has proven that fire could not have caused the collapse, which is a stronger but unnecessary claim.
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... Hulsey shows that correcting these errors reduces the movement to a third of that. As far as I can see, no one has really disputed that. ...[/URL]
This badly misrepresents our critique of Hulsey's presentation in this thread. Hulsey's model is simply insufficient, inadequate to model how that particular girder would move relative to the column. The worst errors in Hulsey's approach are:
He only heats two floors
He has no time resolution of the dynamic fire progression and the differential heating rates of various components, he simply heats the entire model to one temperature distribution at one arbitrary snapshot in time and shows resulting expansion appearing smooth and without discontinuities.
 
NIST's omissions and mistakes line up to increase the girder's movement relative to column 79, taking it to precisely the minimum displacement necessary to initiate the putative buckling sequence for that column. Hulsey shows that correcting these errors reduces the movement to a third of that. As far as I can see, no one has really disputed that. The disputes are over whether Hulsey has proven that fire could not have caused the collapse, which is a stronger but unnecessary claim.

You should take an hour and re-read the thread if the bold text is your current takeaway. Hulsey did not even test NIST's modeled scenario, let alone disprove it. And the model he did run is full of obvious flaws, each of which is far more glaring than the omission by NIST of any minor structural element (e.g., he did not even test an actual traveling fire scenario at all, seemingly failed to properly test for local connection failures, and did not even attempt to model fire damage except for in the northeast corner of two floors, treating the rest of the building as pristine even though at least five additional floors had large traveling fires). The majority of the thread is dedicated to directly disputing, and in fact demonstrating, that Hulsey did not properly correct for NIST's omissions in a way that allowed him to draw any reliable conclusion as to the impact those omissions had on the outcome of NIST's modeled scenario.

How can you think Hulsey demonstrated anything about NIST's modeled scenario when he did not even test NIST's modeled scenario?
 
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You should take an hour and re-read the thread if the bold text is your current takeaway. Hulsey did not even test NIST's modeled scenario, let alone disprove it. And the model he did run is full of obvious flaws, each of which is far more glaring than the omission by NIST of any minor structural element (e.g., he did not even test an actual traveling fire scenario at all, seemingly failed to properly test for local connection failures, and did not even attempt to model fire damage except for in the northeast corner of two floors, treating the rest of the building as pristine even though at least five additional floors had large traveling fires). The majority of the thread is dedicated to directly disputing, and in fact demonstrating, that Hulsey did not properly correct for NIST's omissions in a way that allowed him to draw any reliable conclusion as to the impact those omissions had on the outcome of NIST's modeled scenario.

How can you think Hulsey demonstrated anything about NIST's modeled scenario when he did not even test NIST's modeled scenario?
Several individuals here want to say that not using a full fire simulation over time is a flaw in Hulsey's critique of NIST. I guess I need to understand why you and a few others are saying this, as I don't see how differential heating over time would have enabled the now refuted NIST claim that girder A2001 was pushed off its bearing seat to the west by thermally expanded beams framing into it from the east.

The girder would get trapped behind the column 79 side plate in any scenario. Additionally, there wouldn't even be enough lateral travel to move the web past the seat in any scenario and if it did the web stiffeners on the girder would have prevented the flange from folding in any scenario.

It sound like you guys are groping at straws trying to save a failed hypothesis.
 
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Several individuals here want to say that not using a full fire simulation over time is a flaw in Hulsey's critique of NIST. I guess I need to understand why you and a few others are saying this, as I don't see how differential heating over time would have enabled the now refuted NIST claim that girder A2001 was pushed off its bearing seat to the west by thermally expanded beams to the east of it.

The investigation is about if the building could have collapsed by fire. Heaving different regions in a different order changes things. For example if the cross beams were heated before A2001 expanded then that changes the issue of interference with the side plates. The order of heating of those beams cloud also make a difference. Fires on other floors would also have an effect. Other connections might have failed.

Your focus seems to be too narrow here.
 
The investigation is about if the building could have collapsed by fire. Heaving different regions in a different order changes things. For example if the cross beams were heated before A2001 expanded then that changes the issue of interference with the side plates. The order of heating of those beams cloud also make a difference. Fires on other floors would also have an effect. Other connections might have failed.

Your focus seems to be too narrow here.
Mick, there is no realistic way the beams to the east of A2001 ccould have been heated enough to push it off its seat without the girder also getting nearly as hot and getting trapped behind the column side plate. They were in a close proximity.

Can you provide a truly plausible scenario where failure by fire could occur?
 
Can you provide a truly plausible scenario where failure by fire could occur?

If there are no plausible scenarios, then what is Hulsey testing?

Doesn't the fact that there is an investigation by Hulsey mean that you've not proven that collapse from fire is impossible?

And given that, should he not test all scenarios, even if you personally don't think they are viable?
 
If there are no plausible scenarios, then what is Hulsey testing?

Doesn't the fact that there is an investigation by Hulsey mean that you've not proven that collapse from fire is impossible?

And given that, should he not test all scenarios, even if you personally don't think they are viable?
Hulsey was looking for a plausible way that the building could have collapsed by fire. My understanding is he could not find a way. He originally said he couldn't necessarily say what exactly happened but could say what could not have happened.

NIST was charged with explaining the collapse and their hypothesis has been shown to be impossible. It is clear that they are on the hook to provide a realistic explanation.
 
Hulsey was looking for a plausible way that the building could have collapsed by fire. My understanding is he could not find a way. He originally said he couldn't necessarily say what exactly happened but could say what could not have happened.

So why did he not use time dependent fire behavior? If he did not simulate that then how is he saying it did not make a difference?
 
But surely the point of Hulsey's investigation is "to evaluate the possible causes of World Trade Center Building 7's collapse"?
I am sure you heard him say he could only really say what couldn't have happened while trying to find a plausible way it could have. He says he can't find a way it could have come down by fire and in the process of doing many scenarios he also critiqued NIST's hypothesis and showed it was impossible. Of course, the guys who did it had to know it was too or they wouldn't have left off the girder web stiffeners.
 
But why did he not try differential heating? Did he eliminate it in some way?
Mick, differential heating would not have made any difference in the failure hypothesis NIST claimed. The girder's west corner is only 5/32" from being inside the envelope of the side plate and that only requires a temperature increase of about 70 degrees F to close on a 531" long girder considering both sides to have expanded by that much.

The beams to the east need to be at 600 degrees C to even get close to providing a plausible amount of lateral travel of the girder and there is no chance the beams could get that hot and the girder right next to them, that they are also connected to, will not have a serious temperature increase.

The point you try to make there has no merit.
 
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Can you provide a truly plausible scenario where failure by fire could occur?
This is reversing the burden of evidence.
Hulsey claims that fire wasn't the cause of collapse - in other words: That ALL fire scenarios could not have resulted in this collapse.
It's his burden to prove that.
He tested no (zero) fire scenarios. How did he rule out all others, i.e. all fire scenarios?

You are saying that an argument can be made that no fire scenario would displace girder A2001 on the 13th floor sufficiently relative to Col79. Let's assume for a moment this were true: Hulsey did not look at any other connection. How did he rule out that collapse initiated at any other location?

His study is woefully incomplete and inadequate to prove the global negative claim that he made long before even doing the study.
 
Mick, differential heating would not have made any difference in the failure hypothesis NIST claimed. The girder's west corner is only 5/32" from being inside the envelope of the side plate and that only requires a temperature increase of about 70 degrees F to close on a 531" long girder considering both sides to have expanded by that much.
You are here assuming implicitly, and perhaps unconsciously, that the distance between columns 79 and 44 would be the same as it was in the cool building.
If Hulsey's presentation showed one thing, then that assumptions of that kind are FALSE.
 
This is reversing the burden of evidence.
Hulsey claims that fire wasn't the cause of collapse - in other words: That ALL fire scenarios could not have resulted in this collapse.
It's his burden to prove that.
He tested no (zero) fire scenarios. How did he rule out all others, i.e. all fire scenarios?

You are saying that an argument can be made that no fire scenario would displace girder A2001 on the 13th floor sufficiently relative to Col79. Let's assume for a moment this were true: Hulsey did not look at any other connection. How did he rule out that collapse initiated at any other location?

His study is woefully incomplete and inadequate to prove the global negative claim that he made long before even doing the study.
The burden is and has always been on the NIST to properly explain the collapse. It is somewhat disgusting that a number of citizens had to separately put money out of their own pocket to show how ridiculously inaccurate the NIST WTC 7 report is.

Hulsey says he looked at a lot connections all over the building. It seems you are just focused on his critique of NIST.

You don't seem to be able to back up your criticism of his report. Mere words of derision won't do the job for you. Do you have anything else?
 
You are here assuming implicitly, and perhaps unconsciously, that the distance between columns 79 and 44 would be the same as it was in the cool building.
If Hulsey's presentation showed one thing, then that assumptions of that kind are FALSE.
You should be careful not to pull your arm out of its socket. You are really reaching with no technical basis for what you are saying.

I am asking those of you who claim differential heating would make a difference to provide an example where it would have changed things.
 
I didn't expect you to reply with a technical basis for what you are trying to say and I was right. You apparently can't provide an example of where differential heating would have changed things. It seems you and some others here just wanted to bash Leroy Hulsey's analysis.

No, we want to analyse it, when it is released.

You seem to be conflating disproving NIST's probable collapse sequence with proving the building could not have collapsed due to fire. Clearly differential heating has the potential to alter the outcome. Perhaps it would not lead to a collapse - but how could you determine this without trying that scenario?
 
The burden is and has always been on the NIST to properly explain the collapse.
They did.

Now it is your job to prove they were wrong. Husley hasn't because he didn't model what they did. There is literally no reason not to model what NIST did exactly as far as modeling the actual fire progression.

Husley can pull different beams out (like a Jenga 'game') until the cows come home. But that won't prove anything until he does an [accurate] progressive fire scenario on the building first.
 
Now it is your job to prove they were wrong. Husley hasn't because he didn't model what they did. There is literally no reason not to model what NIST did exactly as far as modeling the actual fire progression.

It's more than that though. Hulsey and AE911 have set out to show that the probably collapse scenario that NIST described is impossible. However the goal of Hulsey's study is "to evaluate the possible causes of World Trade Center Building 7's collapse" - so it should also evaluate other collapses from fire. Tony seems to suggest that because nobody has proposed an exact sequence of events leading to a collapse, then this means that a collapse is impossible.

This ignores two things. Firstly it ignores the fact that the ANSYS damage simulation that was fed into the LS-DYNA simulation included multiple connection failures, and did not rely on the C79/A2001 connection failure. So Hulsey needs to address THAT scenario.

Secondly it ignores the the potential the collapse scenarios could arise from the simulation that are complex, or simply unforeseeable. So the actual conditions (or a representative range of possible conditions) needs to be simulated to see what happens. This needs to be multi-floor, and temporal.
 
They did.

Now it is your job to prove they were wrong. Husley hasn't because he didn't model what they did. There is literally no reason not to model what NIST did exactly as far as modeling the actual fire progression.

Husley can pull different beams out (like a Jenga 'game') until the cows come home. But that won't prove anything until he does an [accurate] progressive fire scenario on the building first.
deidre, if you are a technical person I would hope you understand that certain things can be proved/disproved by inspection.

The NIST probable collapse scenario fits that situation. There is no differential heating scenario that would make it work.

Now as far as whether differential heating could cause a collapse somewhere else in the building I am all ears. Unfortunately, all I am seeing here is a hollow claim that it could with no example provided by any here who are advocating that it could. It certainly isn't a good showing by those who have incessantly been bashing Hulsey's work.
 
Unfortunately, all I am seeing here is a hollow claim that it could with no example provided by any here who are advocating that it could. It certainly isn't a good showing by those who have incessantly been bashing Hulsey's work

See above. Hulsey needs to simulate the actual conditions, otherwise what is the test for?
 
It's more than that though. Hulsey and AE911 have set out to show that the probably collapse scenario that NIST described is impossible. However the goal of Hulsey's study is "to evaluate the possible causes of World Trade Center Building 7's collapse" - so it should also evaluate other collapses from fire. Tony seems to suggest that because nobody has proposed an exact sequence of events leading to a collapse, then this means that a collapse is impossible.

This ignores two things. Firstly it ignores the fact that the ANSYS damage simulation that was fed into the LS-DYNA simulation included multiple connection failures, and did not rely on the C79/A2001 connection failure. So Hulsey needs to address THAT scenario.

Secondly it ignores the the potential the collapse scenarios could arise from the simulation that are complex, or simply unforeseeable. So the actual conditions (or a representative range of possible conditions) needs to be simulated to see what happens. This needs to be multi-floor, and temporal.
Mick, you are now advocating a new investigation.
 
No, I'm advocating that Hulsey fulfils his mandate "to evaluate the possible causes of World Trade Center Building 7's collapse"
Once the results of an official investigation have been shown to be inaccurate and non-explanatory it is the responsibility of those charged with providing an explanation to redo the investigation. Trying to put that responsibility on the person(s) who showed the official explanation did not work is not legitimate.

Hulsey has shown the NIST collapse initiation hypothesis does not work. Nobody here, or anywhere else, has thus far provided a viable and evidence based explanation that would show that WTC 7 collapsed due to fire. If there are other possibilities, with fire as a cause, they need to be shown by officials with the responsibility to provide a legitimate explanation.

The NIST investigation of the collapse of WTC 7 needs to be re-opened.
 
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What is the objective of the Hulsey study?
If it were a scientific study, we should expect it to state affirmative scientific (i.e. falsifiable) hypotheses and to test those. Ideally, scientific knowledge is advanced by falsifying an extant hypothesis AND replacing it with a new affirmative, testable hypothesis that explains the extant body of data better and/or more completely.

Here is a run down of various statements of the purpose of the study, ordered chronologically (and certainly incomplete):

1.
In early 2015, AE911truth published their goals for 2015 on their website. It featured a first mention of the Hulsey study, that was not identified by name, place or budget yet:
BE A PART OF OUR AMBITIOUS 2015 AGENDA
1. New Research Initiatives
• Conduct sophisticated computer modeling of World Trade Center Building 7 to demonstrate, first, the impossibility of the collapse initiation mechanism put forth by the National Institute of Standards and Technology (NIST) and, second, that a controlled demolition more readily replicates the observed destruction.
Content from External Source
2.
In late 2015, the project was announced and the wtc7evaluation.org website created. It stated:
WTC 7 Evaluation is a study at the University of Alaska Fairbanks using finite element modeling to evaluate the possible causes of World Trade Center Building 7's collapse.
Content from External Source
3.
In early September 2017, the Hulsey presentation showed this on a slide:
Purpose of this study
1. World Trade Center Building 7 (WTC 7) was not struck by a plane and yet it
collapsed. Why?
2. The National Institute for Standards and Technology (NIST) issued a report in
2008 concluding that the structure collapsed because fires caused the floor
beams and girders to expand, triggering a series of structural failures that
culminated in the total collapse of the building.
3. Others argue that fire was not likely the cause of the failure.
4. This project was undertaken to answer the question: Did fire cause this
building to collapse?

Content from External Source
4.
At around the same time (~September 2017), a project page was created in the uaf.edu domain; it currently states:
Architects & Engineers for 9/11 Truth provided funding to the University of Alaska Fairbanks (UAF) to evaluate if fire caused the collapse of WTC 7 and to examine what may have occurred at 5:20 P.M. on September 11, 2001.
Content from External Source
5. Finally, and as an aside, I found this on Feng Xiao's LinkedIn profile (undated):
Evaluation of World Trade Center 7 Collapse. (Architects & Engineering for 911 Truth),
ongoing. Evaluation of the WTC 7 collapse is a study using finite element modeling to evaluate the possible causes of World Trade Center Building 7 collapse. The research involves simulating the thermal loading caused by fire, and evaluating the thermal impacts on the building’s progressive collapse.
Content from External Source

So we see there is a moving target:
a) Prove NIST wrong
b) Make a case for controlled demolition
c) Evaluate the possible causes
d) Answer: "Did fires cause the collapse?"

At the end of the day, only one type of affirmative hypothesis would answer all these diverging objectives: A specific, testable, falsifiable hypothesis of controlled demolition evaluated against extant data. Given the infatuation of AE911Truth with details of the NIST-report, we should demand that Hulsey's CD-theory is AT LEAST as detailed and specific as NIST's "most probable" scenario, i.e. he identifies the specific locations within the structure that were attacked, and how, with a detailed listing of the chronology of events, including how the building was rigged.
Everything else AE911Truth should reject out of hand, to remain consistent and regain credibility.
 
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Your arguments are simply not germane to the issue of who bears responsibility. It doesn't matter what Hulsey said he would do. If it is shown that the NIST hypothesis does not work, and it has been, then it is they who bear the responsibility for a viable explanation and that requires that they re-open the investigation of the collapse of WTC 7.
 
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Once the results of an official investigation have been shown to be inaccurate and non-explanatory it is the responsibility of those charged with providing an explanation to redo the investigation. Trying to put that responsibility on the person(s) who showed the official explanation did not work is not legitimate.

Hulsey has shown the NIST collapse initiation hypothesis does not work. Nobody here, or anywhere else, has thus far provided a viable and evidence based explanation that would show that WTC 7 collapsed due to fire. If there are other possibilities, with fire as a cause, they need to be shown by officials with the responsibility to provide a legitimate explanation.

The NIST investigation of the collapse of WTC 7 needs to be re-opened.

Exactly which element(s) of the NIST collapse initiation hypothesis did Hulsey prove not to work? Please be specific and please also tell us specifically how Hulsey isolated those elements for testing while not holding constant the heat model, the building damage on surrounding floors, or the connection failure criteria?

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It doesn't matter what Hulsey said he would do.

Well I'm sure it matters to Hulsey. It should also matter to the people who put up the $316,153 to fund the study expecting "to evaluate if fire caused the collapse of WTC 7 and to examine what may have occurred at 5:20 P.M. on September 11, 2001."

Not only is "evaluate if fire caused the collapse of WTC 7" a deliverable, it's also what he has claimed to deliver in preliminary form.

The findings thus far are that fire did not bring down this building.
Content from External Source
He also claims to have verified the points made about how the girder could not possibly have walked off as described. That's not the issue here. The issue is if he has proven that fire that matches the observations of the day could have caused collapse.

Tony's argument is: (my interpretation) "The walk off scenario has been proven false. Nobody has suggested another scenario. Therefore there should be a new investigation"

The general response has been "Proven how? Sure there's some problem with it, but without a more detailed model it can't be said to be impossible. More importantly: isn't the goal of Hulsey's study 'to evaluate if fire caused the collapse of WTC 7', so shouldn't he do that by simulating the building response under observer fire conditions, including differential heating on multiple floors?"

The topic of this thread IS Hulsey's study. Let us stick to that, and avoid simply rehashing the exact same arguments.
 
Exactly which element(s) of the NIST collapse initiation hypothesis did Hulsey prove not to work? Please be specific and please also tell us specifically how Hulsey isolated those elements for testing while not holding constant the heat model, the building damage on surrounding floors, or the connection failure criteria?

[...]
Upon being pushed to the west by thermally expanding beams in the northeast corner the also heated 13th floor girder between columns 44 and 79 will invariably get trapped behind column 79's western side plate after just 3.5 inches of lateral travel. The girder cannot be made to leave its seat. That is a reality that is fully exposed now.

No differential heating on floor 13 or any other will change this situation. It is time for the NIST to re-open its WTC 7 investigation.
 
Besides from expending beams due to heat , what about the same beams bending and thus maybe compensating for the expension? Has this been taking into account?
 
Upon being pushed to the west by thermally expanding beams in the northeast corner the also heated 13th floor girder between columns 44 and 79 will invariably get trapped behind column 79's western side plate after just 3.5 inches of lateral travel. The girder cannot be made to leave its seat. That is a reality that is fully exposed now.

No differential heating on floor 13 or any other will change this situation. It is time for the NIST to re-open its WTC 7 investigation.

How do you know the girder gets "invariably" trapped? Hulsey didn't test all of the variables that could affect whether it gets trapped. Merely asserting a conclusion doesn't make it so. Specifically, as has been pointed out ad nauseum in this thread, Hulsey did not take into account how the fire progression variable would affect the girder movement relative to the column, nor did he take into account how damage on either wider areas of the floors in question or on the surrounding floors would affect the girder movement relative to the column. Without controlling for these variables, neither Hulsey nor you can claim anything about the girder's behavior was "invariable".
 
No differential heating on floor 13 or any other will change this situation.

None? What if A2001 was not heated at all? What if the girder on the floor below expanded in a way that moved the column south a bit? What if the entire building warped in such a way that the alignment of the beams, girders, and columns was not exactly as pristine as you imagine?

Surely we need to see what the entire building's response to fire was, so we can see if fire could have caused collapse. That's the purpose of the study.
 
How do you know the girder gets "invariably" trapped? Hulsey didn't test all of the variables that could affect whether it gets trapped. Merely asserting a conclusion doesn't make it so. Specifically, as has been pointed out ad nauseum in this thread, Hulsey did not take into account how the fire progression variable would affect the girder movement relative to the column, nor did he take into account how damage on either wider areas of the floors in question or on the surrounding floors would affect the girder movement relative to the column. Without controlling for these variables, neither Hulsey nor you can claim anything about the girder's behavior was "invariable".
It isn't merely asserted. An analysis was done which allowed for NIST assumptions of shear studs breaking on the beams, no shear studs on the girder, and no expansion to the east by the 52 foot long beams.

In case you didn't notice, I explained earlier that the girder would get trapped behind the side plate even if it is only heated a slight amount. Its western corner only has a 5/32" clearance from the side plate and that gap gets closed with a temperature increase of just 70 F. The beams need to be at 600 C (1,112 F) to get anywhere near a plausible amount of expansion and the girder was right next to them and also connected to them. The girder could not possibly stay at room temperature and would thus be in the envelope of the side plate under all possible conditions where the beams would be pushing it to the west.

You have a serious conflict since you insist on supporting the NIST collapse initiation hypothesis in general, but don't seem to be able to articulate a scenario that would work for it.
 
You have a serious conflict since you insist on supporting the NIST collapse initiation hypothesis in general, but don't seem to be able to articulate a scenario that would work for it.

Well, let's wait and see if Hulsey has explored that space adequately enough to say it's possible or impossible. You would think there would be some useful new results.
 
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