AE911 Truth's WTC7 Evaluation Computer Modelling Project

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Best guess there is that it probably is not that easy to get a building like WTC7 to collapse in the manner it did. ... I don't think that the project has yet proven that fire didn't do it.
That was a very verbous and convoluted "NO" to my question, which was whether or not Hulsey's conclusion follows validly from his study as it stands today. It bugs me why you couldn't simply answer with a simple, straight and honest "No"?

In what way do you believe to have "debunked" Dr Hulsey ?
By agreeing that Hulsey's conclusion is INVALID :). Thank you.

...
The progression model has not been released by UAF...
In this respect Dr Hulsey and his team will be more in the know than we are, ...
And this is the other HUGE problem we have with this study:
It was promised in 2015, when MONEY was solicited, that the public would be kept updated throughout the entire duration of the project, and that all data would be made public, such that you, I, everybody can transparently follow the progress.
This promise has been broken. Agreed?

How do you, personally, feel about Hulsey keeping us in the dark for two years and STILL not making his study transparent - contrary to the promises?
 
Did not fail in that specific scenario, with with that specific model.

What about other scenarios? Other models?

Ask him. I'm not up there running the analyses.
He ran analyses that were worst case, If you can't get failure under those conditions then you won't get it under lesser ones.

What he did differently, honestly, was include all the structural elements that NIST purposely omitted. He succeeded in independently verifying what was previously suggested was possible.

You are being unreasonable asking for more and more analyses, different inputs. There is only so much computer resources that can be dedicated to these. How about you assemble a team and choose what you think is relevant?
 
So, in the absence of a possible failure of this girder at C79, where would your next best guess be for initiation of collapse. The transfer trusses maybe ?
NIST's modelling identified numerous potential connection failures. But that's really not the point - the important issue here is that AE911 is claiming that the study proves WTC7 could not have collapsed from fire. This is false.
 
NIST's modelling identified numerous potential connection failures. But that's really not the point - the important issue here is that AE911 is claiming that the study proves WTC7 could not have collapsed from fire. This is false.
I think that given the basis for you or anyone else claiming that "WTC 7 collapsed due to normal office fires" was the NIST report into the collapse of WTC 7 and the serious questions that this study is asking of it, then you no longer have any right to make any such statement.

Do you believe that when the true make up of the connection at C79 is accounted for, that failure of the C79-44 girder is possible when subjected to conditions set out by NIST themselves ?
 
The team are fairly close to getting to a progressive collapse in the model
I'm sorry about interrupting your conversation with an airhead question but .. I am still curious about this. When you say he is getting close to getting a progressive collapse, you mean using fire only right? because if he was using CD charges to try to get a progressive collapse.. well that should be insanely easy to do right?
 
The make up and reaction of a connection element in the model being quantified, as shown in the graphs you refer to, and replicated as an equivalent connection in the model to save processing time for simulation runs. Talking of element models, it is interesting to note from the 2013 thread, that we discussed the COMBIN37 element in NIST's ANSYS model which is a unidirectional element. We don't know what conditions were applied to this element by NIST, ie the FSLIDE% for example, but we know it's unidirectional. Whereas with the UAF study we know what was tried. We know that the friction was reduced to zero, and tried at various increased levels to learn the difference it could have made.

We know nothing at all about the details of the connection models they used in the macro analysis. We have some response graphs that go far beyond that actual failure points, and that is.

Ask Dr Hulsey if he'll share the full data for the connection elements for the two connections in his presentation. i.e the response graphs for the six degrees degrees of freedom, and the failure criteria.
 
...the important issue here is that AE911 is claiming that the study proves WTC7 could not have collapsed from fire. This is false.
And gerrycan has already agreed with us that this is false, and kawika has refused to say it is okay, which means kawika tacitly agrees it is false.

Just noting this to document that everybody around is, as of yet, in agreement that Hulsey's core conclusion is FALSE.
 
I'm sorry about interrupting your conversation with an airhead question but .. I am still curious about this. When you say he is getting close to getting a progressive collapse, you mean using fire only right? because if he was using CD charges to try to get a progressive collapse.. well that should be insanely easy to do right?
In the same way that Dr Hulsey spoke about increasing the thermal expansion rates of steel by 40% and removing column sideplates in order to favour collapse initiated by fire, such conditions could be applied to the model until real world observed events were matched by model behaviour. This would likely IMO involve the removal of many elements partially over many floors.
The point being that if the conditions have to be exaggerated beyond that which is considered reasonably possible in a fire condition to produce such a result, then that goes a long way toward ruling fire alone out, as a sole cause.
NIST should formally disavow themselves from their thermal expansion around floor 13, C79 nonsense as they have no solid evidence base left on which to make that claim.
 
I think that given the basis for you or anyone else claiming that "WTC 7 collapsed due to normal office fires" was the NIST report into the collapse of WTC 7 and the serious questions that this study is asking of it, then you no longer have any right to make any such statement.

Normal office fires? Clearly these were not normal office fires.

I think WTC7 collapsed because the fires and damage caused by the collapse of WTC1, compounded by the lack of water, and the decision to pull the firefighting operation because of the danger of collapse.

The NIST study was to find exactly how it collapsed, they did a reasonable job with their resources, but all models can be improved upon. All models contain mistakes and inaccuracies.

What is lacking here is evidence of something other than fire and debris damage causing the collapse.

Absent that, I don't see a significant need to spend millions of dollars on improving the NIST model.
 
Which of the 2 studies (NIST/UAF) would you say modelled the C79 connection most accurately when compared to the drawings available to both ?
Which of the two studies modelled the fire response of floors 11 and down most accurately, given that Hulsey did not model them AT ALL?

You are concentrating on one single connection in a large and complex assembly. No matter what you comclude about that connection, it will never ever follow that "fire did not make WTC7 collapse". And thus all this talk about that particular connection and how accurately it was modelled by whom is simply vain, useless, irrelevant, as long as you don't also talk about all the other connections and inputs and fire scenarios and fuel loads and possible departures of the as-built structure from any and all drawings in our possession today.

Since that is impossible, we know today already that Hulsey's top conclusion "fire did not make WTC7 collapse" is not, can not, will not be proven by his study.

And you, @gerrycan, know this.
 
Normal office fires? Clearly these were not normal office fires.

I think WTC7 collapsed because the fires and damage caused by the collapse of WTC1, compounded by the lack of water, and the decision to pull the firefighting operation because of the danger of collapse.

The NIST study was to find exactly how it collapsed, they did a reasonable job with their resources, but all models can be improved upon. All models contain mistakes and inaccuracies.

What is lacking here is evidence of something other than fire and debris damage causing the collapse.

Absent that, I don't see a significant need to spend millions of dollars on improving the NIST model.

One other atypical aspect of the WTC7 fires: the fires apparently started on multiple floors (both contiguous and not contiguous) simultaneously. Typically an office fire will start from a single location and spread, which limits its ability to burn at full force in the same general location on contiguous floors at the same time (the fire moves up as the fire below ebbs). See for example, FEMA's report on the fire in One Meridian Plaza, and note how even during that fire they suspended fire fighting operations for a long period after an engineer determined that the building could potentially collapse. Did that engineer have foreknowledge of 9-11 back in 1991?
 
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Normal office fires? Clearly these were not normal office fires.
NIST describe them here as such, when comparing them to other building fires that they describe as "similar"
https://www.nist.gov/el/faqs-nist-wtc-7-investigation

  • The fuel for the fires was ordinary office combustibles at ordinary combustible load levels.
Content from External Source
I think WTC7 collapsed because the fires and damage caused by the collapse of WTC1, compounded by the lack of water, and the decision to pull the firefighting operation because of the danger of collapse.
So reasonably, we should be doing our best to find out what caused this supposed collapse due to fire, and when the official explanation is challenged in this way, at this level, then there should really be a response to that. I do believe that NIST embarked on some real world tests of steel connections subjected to fire, quoting doubts as to the veracity of their previously held assumptions.

The NIST study was to find exactly how it collapsed, they did a reasonable job with their resources, but all models can be improved upon. All models contain mistakes and inaccuracies.
Reasonable would be a hypothesis that was possible. one that isn't possible is not reasonable by any stretch of the imagination. What matters here is who's model is MORE accurate, and why are the resultant outputs (UAF vs NIST) so at odds with each other as to be opposite in direction ?
It would be helpful if you could answer straight the previously asked question as to who's model you think most accurately replicated the connection at C79 having considered the drawings available to both ?

What is lacking here is evidence of something other than fire and debris damage causing the collapse.
As is evidence of the ability of fire to produce the observed results. The progression model will I am sure, answer many questions as to just how robust this structure actually was. Do you not agree that a full release that included a model showing an albeit heavily induced progressive collapse of WTC7 and just what exaggerations had to be applied to induce such a reaction would be conclusive ?
Absent that, I don't see a significant need to spend millions of dollars on improving the NIST model.
Well this has already proven that you would get 2 or 3 highly accurate independent studies for just $1 million. Perhaps if the model data is made widely enough available then the cost of such a simulation would decrease drastically.
The significant need to get to the bottom of what happened to WTC 7 remains the fact that not to do so can only lead to jeopardising publicly safety, at the least in the sense that not to address this, is not to learn, and to do so is to miss a chance to improve the safety of the public in the US and beyond.
 
Taking a bit of a wider view here. Looking at AE911's activities, I suggest they are not particularly interesting in simply getting a new technical investigation. What they really want is to set up a select committee.

http://www.ae911truth.org/images/PDFs/The-Bobby-McIlvaine-Act.pdf


SECTION 1. ESTABLISHMENT.

There is hereby established the Select Committee on the investigation of the destruction of the World Trade Center on September 11, 2001 (hereinafter referred to as the "Select Committee").

Content from External Source

(b) The Select Committee shall take testimony from no fewer than three experts in
engineering or related fields who present evidence supporting the theory that explosives and/or
incendiaries were used in the destruction of the World Trade Center Twin Towers and Building 7.
Content from External Source
I think this may be why AE911 are trying to present this unfinished partial study as conclusive proof that fire was not the cause of collapse. If they were honest about it, that it simply found some inconclusive problems in the NIST simulation, and offers up a sneak preview at a different simulation, then it would not be helpful to the adoption of their act.
 
Well this has already proven that you would get 2 or 3 highly accurate independent studies for just $1 million.

Why are we assuming the accuracy of Hulsey's study? Do you just mean accurate in terms of ensuring every element of the building (material or not) is included in the small portion of the building that is modeled, or do you mean accurate as in all material considerations were properly modeled to arrive at a reasonably accurate outcome? I assume it's the latter you care about. If so, you're certainly jumping the gun with your implicit assumption that Hulsey's study is accurate, no? All you have is a stated conclusion that does not follow from the study at all and a handful of slides, many of which contain curious and incomplete information. Surely you wouldn't have been heralding NIST's study as accurate based on similar levels of public disclosure, right?
 
Again, he did not in any way show that the girder could not (or did not) fail in reality. He claimed to show it would not fail under a very specific scenario he modeled, given the various modeling assumptions he made for such scenario. He did not even definitively show that the girder would not have failed in NIST's scenario as he modeled a temperature scenario different than NIST's and used various other assumptions different from NIST's. Even assuming for argument's sake Hulsey's study is generally accurate (or even just generally more accurate than NIST's), Hulsey did not model any other scenarios (including but not limited to the scenarios already modeled by Arup or WAI) and cannot say categorically that the girder could never fail from fire. Accordingly, neither can you.

I am not twisting anything you are saying. I merely pointing out that you are taking away from Hulsey's study a conclusion that does not follow from it.

I'm taking one of Leroy's structurally accurate study conclusions and forming my opinions. You choose not to accept my opinions. Fine.

There was a WTC7 court case where a so-called expert gave their opinions--under oath!-- opinions that are blatantly false. Grossly inaccurate interpretations of the photographic record which have led to a detailed narrative suggesting fire scenarios on the lower floors of WTC7, when there is NOT ONE SHRED OF EVIDENCE to support such a claim. (Ask Benthamitemetrick for the Torero link)

NIST does the same thing, suggesting a main column buckled because floors failed, because beams and girders failed, because beams expanded, like never before in the history of steel construction. Pulling nonsense out of thin air.

NIST's opinions claim a complicated set of failures that attempts to explain the rapid disassembly of thousands of tons of steel assemblies, not to mention the almost complete pulverization of the composite floor slabs and evidence of severe erosion of steel members never before seen in a structure fire.

Hulsey is to be congratulated for taking on this task to set the record straight. His analyses have brought some sanity back to the table.
 
It would be helpful if you could answer straight the previously asked question as to who's model you think most accurately replicated the connection at C79 having considered the drawings available to both ?

Hulsey's certain LOOKS more like the drawings, with the addition of the stiffener plates and the column side plates. But how did that translate to a mathematical model? What were the models for the other connections? How were they determined?

I don't have a problem with the possibility that the walk-off did not occur as NIST described. The problem is claiming that proves collapse from fire is impossible, or that we need a new study.
 
there isnt a finished study from UAF yet.
Sure, yes. But the connection has been modelled and we have been shown it, along with the drawings.
UAF are way more accurate than NIST.
Inclusion of partial height stiffener plates on the girder.
Inclusion of side plates on Column 79.
NIST omitted both the above, and so much more from their analysis. UAF did not. That much, even at this interim point of the UAF project, is clear.
 
Hulsey's certain LOOKS more like the drawings, with the addition of the stiffener plates and the column side plates. But how did that translate to a mathematical model? What were the models for the other connections? How were they determined?

I don't have a problem with the possibility that the walk-off did not occur as NIST described. The problem is claiming that proves collapse from fire is impossible, or that we need a new study.
So having disproved the walk off theory to you here some 4 years ago, I think it was established back then that a new study was required. And this is such a study.
Yes, more information is required to validate and allow deep scrutiny of just HOW this project came to the interim conclusions that it has, and can state with such confidence that fire was not the proximate cause for initiation of collapse.
I think what really matters here is whether or not you agree with the principle that if, in order to produce a model output similar to observed events, parameters have to be biased beyond that which would be reasonable to expect to exist from a fire, then that is a huge step toward ruling out fire alone as a cause, if for example the said parameters had to be increased to a great extent ?
 
I'm taking one of Leroy's structurally accurate study conclusions and forming my opinions. You choose not to accept my opinions. Fine.

There was a WTC7 court case where a so-called expert gave their opinions--under oath!-- opinions that are blatantly false. Grossly inaccurate interpretations of the photographic record which have led to a detailed narrative suggesting fire scenarios on the lower floors of WTC7, when there is NOT ONE SHRED OF EVIDENCE to support such a claim. (Ask Benthamitemetrick for the Torero link)

NIST does the same thing, suggesting a main column buckled because floors failed, because beams and girders failed, because beams expanded, like never before in the history of steel construction. Pulling nonsense out of thin air.

NIST's opinions claim a complicated set of failures that attempts to explain the rapid disassembly of thousands of tons of steel assemblies, not to mention the almost complete pulverization of the composite floor slabs and evidence of severe erosion of steel members never before seen in a structure fire.

Hulsey is to be congratulated for taking on this task to set the record straight. His analyses have brought some sanity back to the table.

I am benthamitemetric. So should I ask myself for those materials? I am very familiar with the litigation materials and have discussed them at length here and elsewhere, including in this thread. Your bare assertions that they were based on no evidence is neither accurate nor particularly helpful for discussion purposes. You should read the whole thread prior to commenting as a general courtesy, by the way.

And if we really want to "set the record straight," we should talk with precision about exactly what has been demonstrated by Hulsey and others who have modeled the collapse or aspects thereof. This discussion doesn't turn on anyone's opinion.

And most of your post here is just bland, non-specific incredulity backstopped only by your foregone conclusions about what happened, which is neither appropriate for discussion in this thread nor even interesting to discuss, in any event. I'll stop this back-and-forth here unless you actually have something to say specific to the topic of this thread: Hulsey's study.
 
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I think what really matters here is whether or not you agree with the principle that if, in order to produce a model output similar to observed events, parameters have to be biased beyond that which would be reasonable to expect to exist from a fire, then that is a huge step toward ruling out fire alone as a cause, if for example the said parameters had to be increased to a great extent ?

That's a vast hypothetical, since we did not observe what happened to that connection, and that's all that they are tweaking here.
 
Here's a question, did Hulsey even run models with failure criteria on other connections?
Dr Hulsey did state that they were there to answer questions, and I don't speak on anyone's behalf but my own.
In my opinion, having modelled the whole thing to find the stiff point and observe movement relative to that, they logically must have. They would be aware of the capacities, and the forces involved would be observable and *quantifiable.

"quantifiable throughout the whole structure" that should have been really.
 
Dr Hulsey did state that they were there to answer questions, and I don't speak on anyone's behalf but my own.
In my opinion, having modelled the whole thing to find the stiff point and observe movement relative to that, they logically must have. They would be aware of the capacities, and the forces involved would be observable and *quantifiable.

"quantifiable throughout the whole structure" that should have been really.

So I'm a little confused by this then (again same slide in 2016 and 2017)
20170912-133743-q2zv7.jpg

It appears to be modelling the floor structure as a homogenous slab, and then modelling heat expansion in that slab. So there's no discontinuities at all in it, it's just a smooth displacement gradient (I'm assuming in X). So of course there's going to be no failures.

Where did he model, at the macro level, the local displacements of the connections?
 
Here a diagram say C79 moved 1.85" to the east

20170912-135111-j690n.jpg

And he compares it with NIST figure of 5.5" (revised to 6.2")
20170912-135133-pzyv2.jpg

But NIST never said the column moved 5.5". They said the expansions of the beams pushed the girder 5.5" relative to the column.

So the comparison in this slide makes zero sense.
 
So I'm a little confused by this then (again same slide in 2016 and 2017)
20170912-133743-q2zv7.jpg

It appears to be modelling the floor structure as a homogenous slab, and then modelling heat expansion in that slab. So there's no discontinuities at all in it, it's just a smooth displacement gradient (I'm assuming in X). So of course there's going to be no failures.

Where did he model, at the macro level, the local displacements of the connections?

I don't think it is my place to be answering that, but it is a legitimate question, and one that you would fairly expect to be accounted for in the finished project. I am not about to 2nd guess to that extent, but i don't mind giving a personal opinion in other areas.
 
Here a diagram say C79 moved 1.85" to the east

20170912-135111-j690n.jpg

And he compares it with NIST figure of 5.5" (revised to 6.2")
20170912-135133-pzyv2.jpg

But NIST never said the column moved 5.5". They said the expansions of the beams pushed the girder 5.5" relative to the column.

So the comparison in this slide makes zero sense.

In my opinion, what may be happening here is the whole thing could be moving together. I am sure that Dr Hulsey refers to this at some point, but not in a big way.

EDIT - He mentions it here
@55:40 "and by the way they move together"
 
Well this has already proven that you would get 2 or 3 highly accurate independent studies for just $1 million.
based on what Husley said in the Oct 2016 video (at 2 mins in) it kinda sounds like the young man who hasn't left yet*, just wanted to learn the software. So if you hired someone who already knew the software it should be less money. Although, as far as we the public can see now, there is no guarantee the software was utilized properly. You have to admit it is a bit strange that Husley wont release everything.

*Do you know.. the post doctoral guy who left, is he off the team now? or is he still actively working on it somehow remotely? meaning: is the team NOW just the one student and Husley?
 
Here's a question, did Hulsey even run models with failure criteria on other connections?

It's a real question. From Hulsey's slides, we see that a number of beams buckled in their simulation, but there is no indication that any element actually had a connection failure.

In my opinion, what may be happening here is the whole thing could be moving together. I am sure that Dr Hulsey refers to this at some point, but not in a big way.

So basically the entire east side of the building moved together by between 5" and 6"? Mick is right that this displacement map makes little sense if that is what it is purporting to show, right? It looks like that movement would have likely caused catastrophic beam failures across the east side of the building as it also has all internal columns on that side moving only moving around 1" to 2" in compaison. And why would the southwest corner move between 5' and 6" in the opposite direction? Wouldn't that have caused massive failures as well? Very odd.
 
In my opinion, what may be happening here is the whole thing could be moving together. I am sure that Dr Hulsey refers to this at some point, but not in a big way.

EDIT - He mentions it here
@55:40 "and by the way they move together"

This is ridiculous. If everything is moving together then nothing can ever fail. If it's all moving together then the girder stiffener plates and column side plates are utterly irrelevant.

And obviously things do not move together in the real world because it's not a homogenous structure. Unless he modeled it that way, which is wrong.
 
Sure, yes. But the connection has been modelled and we have been shown it, along with the drawings.
UAF are way more accurate than NIST.
Inclusion of partial height stiffener plates on the girder.
Inclusion of side plates on Column 79.
NIST omitted both the above, and so much more from their analysis. UAF did not. That much, even at this interim point of the UAF project, is clear.
I'd still like to see vid of Husleys model where it gets stuck on the lip ie. side plate. It still doesn't look like it would get stuck to me based on the drawings and the placement of the girder.
 
This is ridiculous. If everything is moving together then nothing can ever fail.
I disagree 100% with this statement. You should reconsider it.

If it's all moving together then the girder stiffener plates and column side plates are utterly irrelevant.
I agree. There is not enough movement for them to play the part that they would if there had been more movement.
And obviously things do not move together in the real world because it's not a homogenous structure. Unless he modeled it that way, which is wrong.
Would you not describe the floor system and the beams and girders to be in some way "composite" ?
I would.
 
I disagree 100% with this statement. You should reconsider it.


I agree. There is not enough movement for them to play the part that they would if there had been more movement.

Would you not describe the floor system and the beams and girders to be in some way "composite" ?
I would.

They are composite but the slabs and beams expand at markedly different rates when heated and thus can separate and fail in fires. Is this really a point we need to debate at this juncture?
 
Would you not describe the floor system and the beams and girders to be in some way "composite" ?
I would.

What about the columns?

No, this is just wrong. Are you really going to start arguing that the steel and the concrete can be considered to be a homogeneous slab with a single heat absorption and transfer rate and a single thermal expansion coefficient, and that the columns are essentially free floating in it?
 
They are composite but the slabs and beams expand at markedly different rates when heated and thus can separate and fail in fires. Is this really a point we need to debate at this juncture?
Not at this juncture no. I would rather explore the potential of not considering the outside walls to be infinitely strong. Perhaps it is that difference in the models that accounts for the disparity in the outputs, in part at least ?
 
Not at this juncture no. I would rather explore the potential of not considering the outside walls to be infinitely strong. Perhaps it is that difference in the models that accounts for the disparity in the outputs, in part at least ?

Differences in modeling the perimeter columns could of course lead to differences in outcome, as could differences in modeling the fire scenario, differences in the area of the building modeled, and differences in the treatment of connection failures and the overall displacement of key structural elements, right?
 
What about the columns?

No, this is just wrong. Are you really going to start arguing that the steel and the concrete can be considered to be a homogeneous slab with a single heat absorption and transfer rate and a single thermal expansion coefficient, and that the columns are essentially free floating in it?
So we agree there would be a level of friction between the elements making up the system that could be expressed as a value of being composite overall. I believe Dr Hulsey mentioned several values that were considered, including no resistance.
 
I don't believe that Hulsey has proven anything or can conclude that fire could not destroy a steel framed high rise... a core theme of Gage's CD belief.
 
Differences in modeling the perimeter columns could of course lead to differences in outcome,
NIST had these connections fixed. Not realistic. UAF considered them.
as could differences in modeling the fire scenario,
I believe the project replicated NIST's stated conditions at some point.
differences in the area of the building modeled,
UAF modelled the whole thing. NIST did not.
and differences in the treatment of connection failures
Once an element in NIST's model was "deemed to have failed" it was removed, along with any other element attached to it. NIST's walk off theory is beyond the "in trouble" point. It can be discarded. This is a far more accurate model from UAF that contradicts NIST's findings directly and consistently across 2 programs.
and the overall displacement of key structural elements, right?
Right.
 
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