Sept 3, 2019 release of Hulsey's WTC7 draft report: Analysis

[Mick West]

Source: https://www.youtube.com/watch?v=7OClixCTdDw

Source: https://www.youtube.com/watch?v=a-DadyW-LR4


The above two videos details some issues raised in the thread below (and in prior threads) regarding Professor Hulsey's study.


Draft report and videos at:
http://ine.uaf.edu/wtc7
http://ine.uaf.edu/media/222439/uaf_wtc7_draft_report_09-03-2019.pdf (mirror)

The principal conclusion of our study is that fire did not cause the collapse of WTC 7 on 9/11, contrary to the conclusions of NIST and private engineering firms that studied the collapse. The secondary conclusion of our study is that the collapse of WTC 7 was a global failure involving the near-simultaneous failure of every column in the building. All input data, results data, and simulations that were used or generated during this study are available at http://ine.uaf.edu/wtc7.

Hulsey's Presentation on Sept 3 [Slides enlarges. Question Audio Fixed]

Source: https://www.youtube.com/watch?v=TAEHhDCTaBw

Moderator deirdre

This thread is to discuss the data within Leroy Husley's final draft report funded by Architects & Engineers for 9/11 Truth "A Structural Reevaluation of the Collapse of World Trade Center 7" released September 3, 2019.

This thread should be viewed as an analytical and informational thread, written for outside readers looking for informed analysis. Links and quotes that support your comment, must accompany all observations and objections.
https://www.metabunk.org/metabunks-link-policy.t5158/

This thread will be strictly moderated.

• Off topic observations will be removed.
• Circular arguments will be removed. If you disagree with someone, but have nothing NEW to add to your previous observations, then use the "disagree icon".
• Long winded, gish gallop responses and comments are strongly discouraged and may be deleted.

Please focus on the data WITHIN the report only.

Linking MB's original threads on the topic:
https://www.metabunk.org/ae911-truths-wtc7-evaluation-computer-modelling-project.t5627/
https://www.metabunk.org/debunked-uaf-study-shows-wtc7-could-not-have-collapsed-from-fire.t9056/


Other discussions:
http://www.internationalskeptics.com/forums/showthread.php?postid=12807300#post12807300​

 

[Miss VocalCord]

Draft report up.
http://ine.uaf.edu/media/222438/uaf_wtc7_draft_report_09-03-2019.pdf

It appears the file has been moved to this location:
http://ine.uaf.edu/media/222439/uaf_wtc7_draft_report_09-03-2019.pdf

Besides the already mentioned (in other threads) weaknesses of the report, the first thing I noticed quickly is it appears to me how they fiddled in the collapse of the penthouse (starting at page 93), but for now it is just based on my 'feeling', no hard data.
e.g. look at the collapse comparison in the video at AE (from around 45 sec) :

A bit of 'hard data' regarding the penthouse. According to the report it could only happen when the columns failed at the 45th floor. But this is clearly not seen in the image; We see failure of multiple windows being broken far below that where they don't give any explanation for (as far as I can now see).

According to the report it could only happen when the columns failed at the 45th floor. But this is clearly not seen in the image; We see failure of multiple windows being broken far below that where they don't give any explanation for.

Now I'm getting a bit confused as to what they have been modeling. The (simplified, blue/red) animation doesn't show any internal damage, but it lets the penthouse just drop in. So I guess in this simulation more floors where failing?

The damage to the windows I was talking to can be seen in this image:
[GALLERY=media, 133]WTC_WINDOWS by Miss VocalCord posted Sep 4, 2019 at 12:50 PM[/GALLERY]
taken from this video:


Indeed as somebody said before the windows aren't so much part of the structure of the building but I don't see how such a damage could have been caused in the UAF model simulation.

 

[Mick West]

It appears the file has been moved to this location:
http://ine.uaf.edu/media/222439/uaf_wtc7_draft_report_09-03-2019.pdf

Moved and changed. Although a PDF compare only shows two very minor differences. A couple of black lines in the left margin were removed on pages 79 and 101.
The originally uploaded version was dated 9/3/19 10:05:55 AM
https://web.archive.org/web/2019090...a/222438/uaf_wtc7_draft_report_09-03-2019.pdf

The new version dated 9/3/19 3:26:07 PM
https://web.archive.org/web/2019090...a/222439/uaf_wtc7_draft_report_09-03-2019.pdf

 

[Mick West]

***PLEASE POST IMAGES AND VIDEO ***

If you're going to make a visual comparison, then please do not just describe it. If you are not replying to a post that included an image, then post an image that shows the comparison. If it's a comparison of the motion, then try to make a side by side video comparison. If you just give a verbal description it's wasting everyone's time.

Also, embed full-sized images. Don't link to external images. Don't use thumbnails.

9/11 Threads have historically become very messy and hard to follow. So expect moderation of this thread to be brutal and summary if your posts are at all unclear.

 

[Mick West]

the first thing I noticed quickly is it appears to me how they fiddled in the collapse of the penthouse

That also the first thing I really noticed from just looking at the videos. The difference between what they show and what actually happened are sufficiently dramatic that they cast serious doubt on their models.

In a nutshell, the sides of the penthouse rotate around the TOP of the sides in their model, but in reality, they rotated around the bottom - which is exactly what you would expect.

Notice here the corner closest to the camera - on the right, and highlighted in blue in the simulation. In reality, it pivots around the base, just falling into the building to the left. In the simulation, it does a bizarre, inexplicable pivot outwards.

This is even clearer in the front view

Notice nothing underneath the penthouse is moving. Not only is this motion radically different to observed reality, there's also no explanation for why their simulation would give this result.

 

[Mick West]

Source: https://www.youtube.com/watch?v=luplz1zMU7g

Modeling complex events is hard. Here's a comparison between the NIST simulation of the collapse of WTC7 (left), the actual collapse (center) and a new simulation from Professor Hulsey and his students at the University of Alaska. Notice how NIST is far more accurate in the initial phases of the collapse.

The penthouse on the left is the most obvious difference. With NIST (left) the penthouse folds inwards, the sides pivoting at their bases, this matches reality. With Hulsey (right) the East penthouse (on the left) performs a weird pivot, the base spreading outwards. Very different from reality.

Then when the longer west penthouse collapses, NIST and reality both show it deforming as it collapses. Hulsey's model just slides into the building with zero deformation.

Then when the exterior collapses the NIST model deforms far more than reality, but the Hulsey model hardly deforms at all. NIST also shows a huge amount of interior detail. Hulsey does not seem to show ANY damage, and only shows the top 2/3 of the building.

 

[Gamolon]

Source: https://www.youtube.com/watch?v=luplz1zMU7g

Modeling complex events is hard. Here's a comparison between the NIST simulation of the collapse of WTC7 (left), the actual collapse (center) and a new simulation from Professor Hulsey and his students at the University of Alaska. Notice how NIST is far more accurate in the initial phases of the collapse.

The penthouse on the left is the most obvious difference. With NIST (left) the penthouse folds inwards, the sides pivoting at their bases, this matches reality. With Hulsey (right) the East penthouse (on the left) performs a weird pivot, the base spreading outwards. Very different from reality.

Then when the longer west penthouse collapses, NIST and reality both show it deforming as it collapses. Hulsey's model just slides into the building with zero deformation.

Then when the exterior collapses the NIST model deforms far more than reality, but the Hulsey model hardly deforms at all. NIST also shows a huge amount of interior detail. Hulsey does not seem to show ANY damage, and only shows the top 2/3 of the building.

Mick,

In Hulsey's model to the right in the video above, does the penthouse looks like it springs back together after it has descended in the building? It starts off like someone breaking open an egg by pushing the middle of said egg with the thumbs and pulling the two halves of the egg apart with the finger. Then the penthouse contorts back the other way as it descends, almost looking like the two halves returned together and then bend in the opposite direction

I don't even see the penthouse come apart at all.

See screenshots from video below. Yellow outlines the approximate penthouse structure.

 

[Mick West]

In Hulsey's model to the right in the video above, does the penthouse looks like it springs back together after it has descended in the building? It starts off like someone breaking open an egg by pushing the middle of said egg with the thumbs and pulling the two halves of the egg apart with the finger. Then the penthouse contorts back the other way as it descends, almost looking like the two halves returned together and then bend in the opposite direction

It's rather strange yes, I think it's a result of the overly simplistic model they used. Why it would neatly stop like that is inexplicable, however, they could have explained it. They could very easily have rendered multiple views - and specifically a view with the exterior columns invisible - which would show what is going on.

They describe their tests of removing columns 79-81 as:

4.3 Results of the East Penthouse Collapse Analyses
The linear static analysis results for the simulations where we removed Columns 79, 80,
and 81 at different floor intervals are shown in Figures 4.2 to 4.7 below.

Based on these analyses, we found that Columns 79, 80, and 81 did not fail at the lower
floors of the building (e.g., from Floor 6 to 13 or Floor 13 to 21). We found that the failure of
Columns 79, 80, and 81 at the lower floors of the building would cause the building to tilt
dramatically to the east, which would have been observed in the videos but was not, and that it
would not cause the east penthouse to collapse, because the intact portions of Columns 79, 80,
and 81 above where the columns failed would still support the penthouse.

On the other hand, we found that the failure of Columns 79, 80, and 81 at the upper floors
of the building, especially at Floor 45 all the way up to the penthouse, would cause the penthouse
to collapse into the building as observed, while causing minimal movement of the exterior. It
appears, therefore, that Columns 79, 80, and 81 failed at the upper floors of the building.

They have a model of this:

Figure 4.7: Columns 79, 80, and 81 are removed from Floor 45 to the penthouse. Tilting of the
building is now negligible. The penthouse now collapses, as demonstrated from the significant
amount of deflection given in the figure.

That is viewed from the South, but if we flip it we can compare it to their video:

It's totally different. There's also a lot more realistic deformation. This makes me think that the videos they posted on YouTube were manually animated, and not genuine simulations.

 

[Mick West]

And of course a huge problem for Hulsey is that the Penthouse collapse can be seen progressing much further than they show. As discussed here:
https://www.metabunk.org/wtc7-penthouse-falling-window-wave.t9398/

 

[mudr0]

Wouldn't parts of the internal structure had to have already collapsed and hollowed out (as per NIST) below these broken windows, for air to be pushing smoke out during the external structure collapse?

 

[Miss VocalCord]

Besides the east penthouse; I can't really see how the rest of the penthouse is collapsing in these two simulations:


it seems to start falling into the building without much noticable structural damage below it:
[GALLERY=media, 134]Wtc7_PEnthouse by Miss VocalCord posted Sep 4, 2019 at 1:54 PM[/GALLERY]

 

[Mick West]

it seems to start falling into the building without much noticable structural damage below it:

Yeah, it seems highly unlikely this is an actual simulation of the global collapse. The west penthouse falls like a Super-Mario platform, and none of the interior beams even move anywhere as much.

 

[Mick West]

In the paper, and in video there's Figure 4.16:

This proports to show that the NIST hypothesis is false by showing the building tipping over. However, in order to do this, they appear to have also removed one entire floor of columns at around the 11th floor.

The video then shows the building tipping over in a bizzare manner with ZERO DEFORMATION OF THE EXTERIOR, the top simply passes through the bottom.

Source: https://giphy.com/gifs/VCn5AOzBAr2kgkkTcY/html5


Same thing for 4.20

This is obviously complete nonsense. Not a simulation at all.

 

[Oystein]

The video then shows the building tipping over in a bizzare manner with ZERO DEFORMATION OF THE EXTERIOR, the top simply passes through the bottom.

Source: https://giphy.com/gifs/VCn5AOzBAr2kgkkTcY/html5

The falling top of the building is not only not affected by the bottom, it is also not affected by the ground! It seems to fall right through the ground, as if there were none!

When I first saw the videos, I thought it strange that the building would start to roll over like this, it seemed unrealistically stiff - but know I know one more reason why:

As soon as the lower column ends of the falling top part run into the ground, they would encounter extreme resistance, and that extreme resistance would get communicated through all available load paths to the structure above - and buckle, break, and decelerate it. This would be a mechanism to stop, or at least slow, the rotation. But without a solid ground, there is nothing to resist the structure once it has passed magically through the bottom, and it keeps rolling.

 

[Mick West]

Two more Hulsey visualization of the NIST hypothesis (fig 4.14 and 4.15)

Just a different angle.

These look like different models. Why no videos of these?

 

[Mick West]

So reading the paper a bit more it seems like the two different models (or at least different visualizations) are a linear static analysis and a dynamic analysis.

As I understand it, static analysis ignores time, and hence ignores momentum. It simply takes the building and lets it settle into equilibrium. The building is color-coded based on how much each element is deflected from its original position.

For example, here's the Hulsey/Szamboti hypothesis of removing Columns 79,80, and 81 at floor 45 to the penthouse

The caption reads: "Figure 4.7: Columns 79, 80, and 81 are removed from Floor 45 to the penthouse. Tilting of the
building is now negligible. The penthouse now collapses, as demonstrated from the significant amount of deflection given in the figure."

It seems to me that static analysis is not appropriate for the sudden removal of a column. Notice in the static analysis no connections are broken. Static analysis would not take momentum or impacts into account. However it seems like static analysis is commonly used to test building designs, at least for smaller buildings. The rationale and process is described here.

https://www.govinfo.gov/content/pkg...VPUB-C13-2011e5bbfe219baec2c2e5d71fc5100f.pdf

Progressive collapse is a dynamic and nonlinear event, as it takes place in a very short time frame and structural members undergo nonlinear deformation before failure. To analyze rigorously progressive collapse potential of a structure, nonlinear dynamic analysis should be performed to account for energy dissipation, large inelastic deformations, materials yielding, cracking and fracture. However, the nonlinear dynamic analysis requires step-by-step integration which is very time consuming. Furthermore, because of the general lack of structural behavior data especially related to beam to column connections of both steel and concrete, it is difficult to evaluate the results of the analysis. As a result of these reasons, nonlinear dynamic analysis is not used in routine design and analysis of low- and mid-rise buildings, which account for nearly 93 percent of buildings in the U.S.

2.2 Nonlinear Static Analysis In nonlinear static analysis, geometric nonlinearlity resulting from large deformations can be accounted for through the redistribution of loads as a result of the removal of a critical column (Fig. 1), and the structure attempts to reequilibrate to the larger spans through a change in behavior from a flexural response to a membrane response. In analysis the loads are applied in steps starting at zero to the total load level as defined by Eq. 2. At least 10 steps are recommended by UFC [UFC 2004]. At the end of the analysis, the predicted forces, moments, shears and deformations must be checked against the acceptance criteria (Table 1).

If none of the structural members and connections violates the acceptance criteria, the analysis is complete and satisfactory resistance to progressive collapse has been demonstrated. If one or more members violate the acceptance criteria, the analysis is repeated with a modified structural model by removing failed structural members, and the load is applied incrementally again. This incremental/iterative process continues until the structural model stabilizes. If the collapse process cannot be stopped, then the structure must be re-designed and re-analyzed. If the structural model does stabilize, then the performance criteria of the damaged area must be checked.

Summary: Redistribute the loads, calculate deformation, if something breaks then remove it, repeat until things settle down.

Problem: Hulsey says: "The penthouse now collapses, as demonstrated from the significant amount of deflection given in the figure"

That does not appear to be how it works. The Penthouse may well be just hanging there in a deformed state. We need to see the actual acceptence criteria of the members, and if they have been violated - not just an eyeballing. And again, the sudden collapse of a column is a fast-moving event, really needing dynamic analysis.

Later on, we have a more dramatic result of static analysis:

This seems like rather a reach for static analysis. Unless this was moving at a slow creep, and then stopped at this angle, this something that needs to be modeled dynamically.

Of course they DO some dynamic analysis. But the results, as discussed above, are ludicrous.

Conclusion: Their global collapse analyses are worthless and misleading.

 

[deirdre]

and what is happening here? they added stretchy columns to their physics model? this isn't normal in a model right?

 

[Mick West]

and what is happening here? they added stretchy columns to their physics model? this isn't normal in a model right?

I think it's the result of pushing a static analysis far beyond what it was intended to do. Clearly those columns would have failed long before that point, but for some reason, they are still there, all stretched out.

 

[Jeffrey Orling]

Any collapse "model" which shows a basically intact upper part.... 30-40 stories in the case of 7wtc would rely on extensive damage below that block rendering it unstable, unsupported and so it would drop down (crush up)

The pre descent of the block and "descent"/collapse of the EPH would have had to have been a local event up at the 46th floor... or one somewhere below it in its supporting columns (which is what appears to be what happened).

How this event led to a global collapse is curious for any CD scenario unless the columns below the EPH down low were CD in advance of the others required for the collapse of the top block. Hardly seems intentional or part of some engineered sequence.

 

[Oystein]

Things I will look for:

• Do they make ALL data available - the full ABACUS and SAP2000 models, all parameters, all runs? They promised full transparency
• Did they test any CD dynamic full collapse scenarios with accumulated damage to the structure - from hours of fire (weakend and failed connections on all fire floors, impact damage from WTC1 collapse, ...)? NIST's two simulations - one with impact damage, one without - showed that the outer appearance of how the perimeter comes down depends critically at least on prior damage to external columns on the south and west side
• Did they expand the area in which they looked for fire damage to more than just the two floors we know they considered earlier in the project?
• And of course any instance of making a global claim without covering (enveloping) the entire space of possibilities
• Do they reference and discuss all the other studies (ARUP, Weidlinger, ...), as well as the literature that builds on the NIST report - such as the papers that NIST's lead authors (McALister, Gross) themselves placed in prestigeous journals?
• Any unscientific references, any text passages copied&pasted from Truther works without proper attribution

Also to look for - in their "CD" model, where they cut columns to mimic the actual collapse:

• Do they provide estimates how many and how large CD charges would have to be to effect that?
• Are these charges placed in areas where there were fires? Any suggestions how they would survive the fires?
• Any estimates about the other effects of such charges, such as making loud sounds or blasting out windows, that can be compared to observations?

I am asking, because NIST did all that.

Ok, now that I have read a first pass through the full report, I'll try a few preliminary answers to the questions I raised:

1. "Do they make ALL data available"
   -> Promised now for later in the month
2. "Did they test any CD dynamic full collapse scenarios with accumulated damage to the structure - from hours of fire (weakend and failed connections on all fire floors, impact damage from WTC1 collapse, ...)?"
   -> Hulsey says in Section 4.2, page 93:
   "For all collapse models and analyses, we included the debris damage assumed by NIST, which involved six exterior columns on the southwest face of the building reportedly being
   severed by falling debris from the collapse of WTC 1."
   So yes, impact damage is included, but I do not see if and how any accumulated fire damage is considered - it appears Hulsey found NO damaged connections or other structural elements.
3. "Did they expand the area in which they looked for fire damage to more than just the two floors we know they considered earlier in the project?"
   -> No.
4. "any instance of making a global claim without covering (enveloping) the entire space of possibilities[?]"
   -> Yes. E.g., he dismisses the Weidlinger results out of hand.
   
5. "Do they reference and discuss all the other studies (ARUP, Weidlinger, ...)..."
   -> Yes - briefly.
   "as well as the literature that builds on the NIST report - such as the papers that NIST's lead authors (McALister, Gross) themselves placed in prestigious journals?"
   -> No.
6. "Any unscientific references, any text passages copied&pasted from Truther works without proper attribution"
   -> Yes (ignoring "unscientific"), e.g. Szamboti's calculation of the dropped floor 13 segment in Section 3.3.1. - Hulsey writes on page 87:
   "To determine the stiffness of the falling Floor 13 beam and girder assembly, a finite element modal analysis was performed...",
   and this analysis found that
   "[T]he natural frequency of mode 2 in the vertical direction is 0.51693 hz"
   This ridiculously precise number (5 relevant digits!) has a source: T.Sz. @ Metabunk: Post #200 in this thread, where Tony Szamboti wrote:
   "Attached is a pdf with views of the FEA results. In case you are wondering the information on the upper left says 5.1693e-01 Hz"
   - the precise same 5 relevant digits. Later, in Post #231, relates how he computed the mass to be input to the FEA by hand:
   "I was doing the 20,000 pounds from memory while writing the post. I think I checked the mass in the FEA, which would have been very accurate. By hand I get ... [snipped detailed tally] ... So I get 5,850 + (4 x 2,915) + 2,288 + (3 x 76 lbs.) = 20,026 lbs."
   And later on he explains how he fiddled a bit with the model input, to demonstrate how increasing the mass a bit has no significant influence on the natural frequency.
   So I walk away from that thread convinced that Tony is the author of that FEA and the values that Hulsey presents - but Hulsey does so without acknowledgement of Tony's authorship; the string "Szamboti" appears nowhere in the Draft.
   Will have to look for more uncreditet Truther input. In the introductory sections, Hulsey attributes several general claims vaguely to anonymous "independent researchers" or similar attributions.
7. Do they provide estimates how many and how large CD charges would have to be to effect that?
   -> No. Except that ALL columns, core and perimter, are involved. Page 111:
   "4.7 Summary and Conclusion ... It is our conclusion that the collapse of WTC 7 was a global failure involving the nearsimultaneous failure of all columns in the building" (my bolding)
8. Are these charges placed in areas where there were fires? Any suggestions how they would survive the fires?
   -> Yes. Almost certainly. Pages 109/110:
   "It should be noted that we conducted two separate simulations involving the failure of the core columns and exterior columns over 8 stories ... Based on our subsequent review of video footage, we found that Floor 16 is the uppermost floor where the collapse could have initiated"(my bolding)
   This means that Hulsey hypothesises that columns, core as well as perimeter, were removed on several (at least 4) of the fire-affected floors 7, 8, 9, 11, 12, 13.
9. Any estimates about the other effects of such charges, such as making loud sounds or blasting out windows, that can be compared to observations?
   -> No - and I fear they pre-emptively rule out that question on the current AE project page:
   "[We] welcome any and all members of the public to submit constructive comments intended to further the analyses and presentation of findings contained in the report."(my bolding)
   This sounds a bit like they rule out comments about findings not already contained in the report - this would apply to any talk of "demolition" or "devices", words which are not "contained in the report".

 

[Oystein]

Section 3.3.1, "Discussion of Arup and Nordenson's Analysis" on pages 86-89 is mostly a presenattion of Tony Szamboti's FEA that Tony presented in January 2016 here at Metabunk - but Tony is not acknowledged by Hulsey.

From the Draft, page 87:

To determine the stiffness of the falling Floor 13 beam and girder assembly, a finite element modal analysis was performed with the assembly constrained at the north and east exterior walls and the girder sitting on its bearing seat at Column 44 with the bolts at the girder seat broken. The results are shown in Figure 3.15. The first mode of 22 Hz involved only the beams moving in a transverse direction and was not relevant. The second mode of 0.52 Hz involved the participation of the entire beam and girder assembly in the vertical direction andwas relevant.

Here is said Figure 3.15:

This Figure is lifted without changes (except for adding a caption, obviously) from the 2nd page of this PDF, which Tony Szamboti uploaded as part of Post #200 on Jan 22, 2016 in the old "Does the exclusion of stiffness from Nordenson's falling girder calculations demonstrate anything?" thread. Note the "Mode2" value of "+5.1693E-01", which Tony reproduced in said post #200 in all its 5-relevant-digits glory - and so does Hulsey on the next page:

The natural frequency of mode 2 in the vertical direction is 0.51693 hz.

In context of the old discussion here (e.g. Post #231) it is clear that Tony implies this FEA is his work.

Yet Hulsey does not mention Szamboti at all in all of the Draft.


[I cut this text on edit, thinking I was in the wrong thread, but I wasn't ^^ so pasted back]

 

[Miss VocalCord]

"Did they expand the area in which they looked for fire damage to more than just the two floors we know they considered earlier in the project?"

Regarding the fires I noticed this in the draft on page 22:

Several factors warranted extra technical examination:
a...
b. The lack of combustibles was critically examined, as was the idea that primary damage by fires could occur on floors where financial centers were located. The questions we addressed were: Would this type of business have paper lying around or would privacy be most important and therefore paper stock locked in a fireproof safe? Why was a fire in this building so significant?

However I can't find any answers on the questions they raise in the rest of the pdf?

 

[Mick West]

This proports to show that the NIST hypothesis is false by showing the building tipping over. However, in order to do this, they appear to have also removed one entire floor of columns at around the 11th floor.

I realize now why they do this. It's because the top part of the building is simply being rotated manually. If they left those columns in they would stretch between the top and the bottom.

There's no dynamic analysis going on here.

 

[igoddard]

I realize now why they do this. It's because the top part of the building is simply being rotated manually. If they left those columns in they would stretch between the top and the bottom.

There's no dynamic analysis going on here.

That has to make you wonder why they would end up deciding to come out with dramatic conclusions backed up by what seems rather like a made-up cartoon. In going against the official report, they needed to at least match the detail of NIST's graphics. Instead their presentation looks super cheap and wonky. They needed to blow people away on first sight, instead it looks embarrassingly low budget. Considering how rapidly software advances, how old the NIST report is and how long the Fairbanks project took, they should have exceeded the graphical presentation of NIST. Instead, their graphics look like they're from software 10 years older than NIST used.

The best path of critical examination to take would be to acquire their software and plug in their data.

 

[igoddard]

Source: https://www.youtube.com/watch?v=luplz1zMU7g

Hulsey presents two of his models side-by-side with the real event, and they appear to be timed very well here:



In his second model, the penthouse portion falls further. I get the feeling they have numerical models and then just crudely translate them by manual manipulation to a low-budget graphical 3D program. In other words, their numbers for a model say the penthouse falls x distance, so then someone with a 3D program just moves it x distance by hand. In short, there's not a seamless automated interface between the number-crunched modeling and the 3D model.

 

[Jeffrey Orling]

The progressive failure which likely occurred which he dismisses... was likely very rapid and conceptually not much different from a simultaneous column failure he claims accounts for the collapse form.

It's likely that the central structure rapidly failed progressively for East to West. This led to the core/interior collapsing and that undermined the perimeter moment frame which appears to rotate and distort at the vertical kink... which he ignores. That kink is a tell and should not be ignored. As there were some perimeter curtain wall on top of the debris pile this too is a tell that it came down a bit after the interior.

The issue is how were the initial failures driven by fire. Because once they failed the REMAINING progressive collapse did not involve FIRE or HEAT as a driver... it was all mechanical overload and failures.

Heat can fail steel frames by several mechanisms... weakening, expanding and then contracting, warping and shearing failing member connections.. displacing column to column connections to the point of crippling and buckling. Load redistribution and failure will progress rapidly once it gets going.

Model that Hulsey!

 

[drommelsboef]

It is very good to be critical about a simulation. The only thing that annoyes me is that double standards are used. The Nist simulation was far from perfect but good enough to conclude that fire explained everything. what Hulsey does is to remove some columns to fit with the observed collapse. The fact that he places the cut at column 79 at a higher place is to get something that looks more like the observed collapse which seems very reasonable to me.

 

[Mick West]

The fact that he places the cut at column 79 at a higher place is to get something that looks more like the observed collapse which seems very reasonable to me.

It would be reasonable if he actually showed a dynamic analysis, using a validated model, of the different column removals. He does not - he shows a static analysis of each one. You can't do static analysis of a building that's already experiencing a highly dynamic collapse. That's basically like saying if you really carefully removed part of C79, then gently lowered the upper part down, then it would not collapse.

His "dynamic analysis", again, is just a manual animation of a rotating block.

Source: https://giphy.com/gifs/W5OZ23LhP9ZVokbiNh/html5


Compare this to NIST who did an actual dynamic analysis. Note this is supposedly the SAME simulated situation.

Source: https://giphy.com/gifs/QZsmWIwXMzAPBSbjEo/html5

 

[Oystein]

Something that's entirely redundant in the report - or even counter-productive:

In the Introduction, Section 1.1 "Background", Hulsey writes on page 11f, to justify the study and its objectives:

Concurrent to and since the NIST investigation, many independent researchers have also studied the collapse of WTC 7 and assembled a body of evidence that raises questions about the validity of NIST's conclusions. That evidence includes the following:

1. WTC 7 experienced between 2.25 and 2.5 seconds of free fall (i.e., gravitational acceleration) during its collapse. This fact was first identified by independent researcher David Chandler and later corroborated by NIST (Figure 1.6). WTC 7's free fall is noteworthy because, in a typical building collapse, WTC 7 would be expected to experience a combination of axial rotation and bending of members, resulting in a disjointed, asymmetrical collapse. Asymmetrical, tipping behavior is especially likely because WTC 7 did not have planar symmetry.
2. The debris pile of WTC 7 was contained mostly inside the building's footprint. Furthermore, it did not have large pieces of concrete flooring or intact structural framing that would be expected in a building collapse (see Figure 1.7).
3. According to Appendix C of FEMA's May 2002 report, a steel member recovered from WTC 7 was found to have experienced corrosion due to a combination of oxidation and sulfidation at 1,000°C, resulting in the formation of a liquid eutectic (see Figure 1.8). Researchers have hypothesized that the presence of thermate, which is a form of thermite incendiary that includes sulfur, would explain the sulfidation and formation of a liquid eutectic (Jones, 2006 and 2007).

These anomalies combined with the fact that there is no prior instance of a tall building undergoing total collapse due to fire led us to reevaluate the hypothesis of fire-induced failure for the collapse of WTC 7.

IMO, this entire page does not belong in this report, in addition to being chock-full of errors. Point by point:

a) He says "many" independent researchers, but goes on to only reference two: Chandler and Jones.

b) Freefall acceleration and rotation/bending are not mutually exclusive. WTC7 DID rotate and bend (kink) while it also exhibited FFA. He thus fails to justify why FFA is noteworthy. He makes bare assertions as to what "a typical building collapse" would look like.

c) The building, even according to Figure 1.7,, was no contained inside the footprint - it spilled beyond its premises on all sides, and severely damaged at least two buildings across 2 different streets:
- "Fiterman Hall was heavily damaged from the collapse of 7 World Trade Center on 9/11." (across Barclay St) (Wikipedia)
- "The south and east facades of the Verizon Building were heavily damaged in the September 11 attacks, from the collapse of the adjacent 7 World Trade Center" (across Washington St) (Wikipedia)
Hulsey failed to justify why dropping the way WTC7 did was remarkable.
Hulsey failed to demonstrate that his best fit collapse progression model (Section 4.6) resulted in a debris distribution similar to Figure 1.7, and had large wall segements hitting Fiterman Hall and the Verizon Building. Without such a demonstration, and without explaining why the debris distribution is remarkable, the whole point is moot.

(Note: Debris spilled across Barclay St (bottom of the photo), Washington St (right), Vesey St (top) and West Broadway (left))

d) Hulsey does not justify why the hypothesized presence of "thermate incendiaries" etc, even if true, would be remarkable, especially as Hulsey has chosen not to speculate at all, in conclusions, on what may or may not have caused the unexplained removal of all columns almost simultaneously, or how the hot corrosion documented by FEMA Appx C would help explain such a sudden removal. He ignores that Jones subsequently, as co-auther of Harrit et al 2009, no longer hypothesizes "thermate" with sulfur as hypothetically present at the WTC and responsnible for the destruction - the exact opposite is true: He speculated in 2009 that any sulfur in the suspected material would be sulfur.
So this entire point comes down to old speculation, that Hulsey's study ends up shedding on no light at all.

e) Even if it is true that no tall building has collapsed due primarily to fire before 09/11/2001, this has happened subsequently - and even if it had not happened subsequently, there is no reason and argument whatsoever why a tall building should not be able to collapse from fire: It is well known that non-tall structures collapse from fire all the time. There is no height above which some magic protects structures from fire-induced collapse.

 

[Oystein]

Page 91:

4.1 Key Features of the Collapse

Based on our review of video footage and of the NIST and FEMA Reports, we identified three key features that occurred during the collapse of WTC 7, which we then attempted to replicate in our simulations of the collapse. These three key features are as follows:

1. The collapse of the east penthouse, which begins approximately 6.9 seconds prior to the descent of the north face roofline;
2. The collapse of the screenwall and west penthouse, which begins approximately 0.5 to 1 second prior to the descent of the north face roofline; and
3. The descent of the north face roofline, which progresses at a rate of free fall for approximately 2.25 to 2.5 seconds over a distance of approximately 105 feet or 8 stories, during which the building's sheathing remains attached to the exterior steel framing and does not experience visible differential movements.

a) Why are these, and only these, singled out as "key" features? Why not the rotation of the building, the acceleration profile before and after the FFA, the window breakage, the kink, the impact into Fiterman Hall and the Verizon Building?

b) He says western roof structures began to fall 0.5 to 1 seconds prior to north wall descent, but in their prefered simulation, Section 4.6, page 106, they do it 1.3 seconds later - why? -> "...we then simulated the simultaneous failure of all core columns over 8 stories followed 1.3 seconds later by the simultaneous failure of all exterior columns over 8 stories."
Why model the core columns as failing simultaneously, when the roof structures were observed to fail sequentially from east to west?

c) "[no] visible differential movements" - why did they not measure this? Is visual appreciation sufficient?

 

[Oystein]

It is very good to be critical about a simulation. The only thing that annoyes me is that double standards are used. The Nist simulation was far from perfect but good enough to conclude that fire explained everything. what Hulsey does is to remove some columns to fit with the observed collapse. The fact that he places the cut at column 79 at a higher place is to get something that looks more like the observed collapse which seems very reasonable to me.

NIST and Hulsey attempted to demonstrate things with a fundamentally different logical structure: NIST showed that a collapse sequence they found resulted in a fairly similar visual result - knowing the limitations of modelling, and of was known about the conditions of the building, I think this was sufficient to establish plausibility, even if it was not possible to match perfectly.
Hulsey's goal was, primarily, to prove a global negative - which requires different standards of proof.
His Section 4.6 simulation conjures up a totally unexplained disappearance of columns - and manages to replicate only one feature of the collapse - the FFA. Which is entirely trivial: If you make something fall freely, it will fall freely.
But he didn't replicate...

• the collapse or the East Penthouse correctly, as Mick showed earlier
• the kink that formed in the east part of the roof
• the flectures
• the counter-clocwise rotation of the building
• the fall of the north wall onto the roof of Fiterman Hall

Essentially, Hulsey himself erected a standard of precision that he wants to hold NIST to (without actually giving a reason), and then fails that standard.

Plus, our criticism is that the models behave in unreal ways (no deformation; falling through the ground). This shows that the simulations he presents cannot possibly represent a realistic collapse. So even if they result in features that resemble features of the real collapse, this is contrived. The simulations do not offer an explanation for WHYT the building would fall like that. NIST's simulations do.

 

[Mick West]

Notice that in Hulsey's showcase animations of the collapse, the ones that are supposed to match reality, he does not show the entire building.


Source: https://giphy.com/gifs/LNg0rhHXdBNJRxvXmc/html5


In addition, there's that mysterious missing floor.

 

[Mick West]

The amount this upper portion falling would also put it under the ground.


Source: https://giphy.com/gifs/YQMShVauCKCli6RM8x/html5

(also attached in higher resolution)

 

[Mick West]

Let's try motion tracking the corner of the building

Plot of Y velocity.

Rather noisy, but essentially constant acceleration for a bit over 2.5 seconds. Which, of course, was both what they were going for, and the obvious result of removing enough columns to make that happen.

 

[Miss VocalCord]

The amount this upper portion falling would also put it under the ground.

Indeed I did notice it also earlier today, weird since the clip is called "Near-Simultaneous Failure of All Columns", but no failing of any column is shown.

 

[Oystein]

Indeed I did notice it also earlier today, weird since the clip is called "Near-Simultaneous Failure of All Columns", but no failing of any column is shown.

My idea of what they are doing to "fail" the columns is this:
They simply make all columns literally disappear.
Then the building falls at free fall.
Of course, after falling one floor, floor slab runs into floor slab - what happens then is a guess: Either the falling floor slab disconnects from its columns, or the slab pass though each other without interaction.
Either way, there is no deceleration - jolt. Someone call T.Sz.!

 

[Oystein]

Mick, have you archived the simulation videos?

Have you archived the presentation video at the UAF media center? https://media.uaf.edu/media/t/0_xf8c7khp
Has anyone watched this presentation? Is it worth 72 minutes?

 

[Oystein]

In the presentation (UAF, September 3rd), at 10:58 minutes, Hulsey says this - an eye-opener IMO:

10:58: My focus was to ensure without a doubt that we had
11:02: pure scientific solutions. We were not going to be influenced
11:08: by previous research, and we were not going to allow
11:11: those with different opinions to influence the science.

Say what? They intentionally made sure they were surrounded by uncritical voices?? Is that why those of who signed up with the study in 2015 never heard back from Hulsey?

 

[Spectrar Ghost]

In the presentation (UAF, September 3rd), at 10:58 minutes, Hulsey says this - an eye-opener IMO:

10:58: My focus was to ensure without a doubt that we had
11:02: pure scientific solutions. We were not going to be influenced
11:08: by previous research, and we were not going to allow
11:11: those with different opinions to influence the science.

Say what? They intentionally made sure they were surrounded by uncritical voices?? Is that why those of who signed up with the study in 2015 never heard back from Hulsey?

That's a very strange quote indeed. It sure doesn't sound like science to specifically exclude the previous body of evidence and critical voices from the process.

 

[Mick West]

Mick, have you archived the simulation videos?

Yes, and I linked them in the OP here.

Have you archived the presentation video at the UAF media center? https://media.uaf.edu/media/t/0_xf8c7khp

Source: https://www.youtube.com/watch?v=TAEHhDCTaBw