1. Mick West

    Mick West Administrator Staff Member

    So now you think that when the fire heated the beams and the girders they all expanded at more or less the same rate, and they pushed the columns around, so there was no displacement at any of the connections? What's the largest displacement between adjacent parts in this diagram

    20170912-143605-79a4t.
    C79 is in the middle of the 1.47 to 2.03 band, and says it moved 1.85 east, 0.94 North (or maybe sourth).

    But it ALSO means that the beams and the girders and the slab all moved smoothly with it. That makes zero sense.

    (EDIT) and means the comparison to the NIST 5.5" figure is meaningless.
     
  2. gerrycan

    gerrycan Banned Banned

    At this point, Dr Hulsey explains what the movement is relative to in the model.
     
  3. benthamitemetric

    benthamitemetric Active Member

    Perhaps not as realistic as they could have been. Materially unrealistic? Remains to be seen. Were all of the elements on all of the floors except for 12 and 13 fixed in reality?

    You believe in error. They did not model NIST's fire scenario at all. They didn't even model an actual fire scenario. They applied certain max temperatures from the NIST studies to certain elements (beams/girders/columns) according to their structural element type. There was no actual fire progression model used. I've pointed this out several times, so perhaps you should take a few moments to review the thread's contents.

    No. They modeled fire damage on only two portions of the east sides of floors 12 and 13. They did not model any other fire damage in the building.

    How were connection failures or buckled elements treated in Hulsey's model, again? As far as I can tell, we don't actually know, so its really putting the cart before the horse for you to claim Hulsey's treatment of them was more accurate than NIST's.

    Glad we agree.
     
  4. Mick West

    Mick West Administrator Staff Member

    But that's irrelevant. As the collapse criteria is the movement of the connection point of one member relative to its connection point on the other member. That's what the 5.5" refers to. So the comparison is invalid. And this displacement diagram is meaningless because it's not going to cause any failures, or even put any strain on anything, because there's no discontinuities in the displacement.
     
  5. Mick West

    Mick West Administrator Staff Member

    The columns (inner and outer) must have some resistance to moving. They are not floating in space - which is how it looks like they are modelled here.
     
  6. Oystein

    Oystein Active Member

    ...one one (1) out of thousands of connections and other elements.

    They are FAR less accurate on most of everything else, such as the entire business of assessing the fire situatiuon, or the floors below and above the two they considered.

    So which was, overall, the more accurate model?

    Again? Such question (yours primarily; mine obviously, too, as I am mocking yours) are silly and a detraction. Your focus on one (1) element to the exclusion of literally everything else is [...].
     
    Last edited by a moderator: Sep 14, 2017
  7. Oystein

    Oystein Active Member

    This is a misunderstanding of the NIST model!

    NIST did not model the walls infinitely strong. They merely did not give the connections within the wall any specified failure modes.
    I detailed that in a post earlier tonight, which got duly ignored.

    Hulsey does not understand the NIST modelling in a couple of aspects. That is worrisome.
     
  8. Oystein

    Oystein Active Member

    Both gerrycan and kawika have already agreed that Hulsey's conclusion is invalid. Tony Szamboti already agreed to this tacitly the other day.
     
  9. Oystein

    Oystein Active Member

    More precisely: NIST did not consider any connection failure modes within the walls, having determined from real-world observation and from preliminary models that this would be unlikely anyway.

    Now: Did Hulsey's modelling observe and failure modes occurring within the wall? Or did his model show that no connection with in the walls failed?
    If the latter, then Hulsey has validated NIST's judgement to not consider the potential of connection failure within the walls.
     
  10. Oystein

    Oystein Active Member

    Since the issue of allegedly "infinitely stiff exterior walls" has been brought up despite it having been debunkted two pages ago, allow me to repost:


    On pages 19 and 20 of his presentation, Hulsey shows the floor area inside which NIST modeled connection failures, and outside which they did not. This is from the 16-story ANSYS model, Hulsey shows NIST's "Figure 11–9. Area of the floor where connection failures were modeled" on page 476 of NCSTAR 1-9 (Although, weirdly, his presentation actually references NIST 2004 - why would they do that? I imagine that he took recourse to a very old AE911Truth presentation given to him). Note the bolded word: failures. It's the operative word here! NIST provides an explanation for their choice:

    Hulsey does not address this. Instead, he claims:

    This omits what NIST actually did to model damage to the western part (which is not entirely irrelevant, IMO):


    More importantly, Hulsey claims that "2. Connections were not modeled for the exterior moment frame". I think he (and now @gerrycan !) misconstrues this as "exterior moment frame was totally rigid". But read the NIST report in context: You find this all in section "11.2.5 Modeling Connections", which starts on page 473. On the same page, they start discussing "Modeling Failure with Break Elements". The critical sentence is on page 475:

    Bolding mine: It's not that they didn't model the connections at all - they probably did! -, they just didn't allow for the connections in the wall or west of the selected area to fail under the modelled loads. I thus assume that particularly the east wall was allowed to respond laterally to the pressure of expanding floor beams. I have not found explicit confirmation of this, but hints such as on page 490 (my bolding):

    Also, Section "11.2.7 Boundary Conditions and Loads" does mention how the top and bottom of the 16-floor model were fixed, but do not mention that the walls or the western part are fixed, so I assume they were not.

    (Page 21 of the presentation presents a quote attributed to "NCSTAR 1-9 Page 525, 2008" - but it's neither on the actual page 525, nor on page 525 of NIST's PDF. I again wonder if he lifted this from some very old AE911Truth presentation).

    To summarize: Hulsey tries to convince us that the 16-floor ANSYS model of Chapter 11 was modelled with the exterior and the western part made rigid, when in fact NIST had only decided not to model connection failures outside the east floor framing. They did allow the exterior and the western part to respond laterally to what the beams did when heated.


    Now on to a big blunder in Hulsey's presentation, which he hasn't corrected since a year ago - and it is a pity that AE911truth as well as other Truther sites actively censored me:

    Please turn to page 24:
    Hulsey (2017) - Page 24.
    • On the left, he again shows Figure 11–9. Area of the floor where connection failures were modeled, only upside down now. Notice: This is a boundary within the ANSYS model.
    • On the right, he shows a snapshot from LS-DYNA animation, a model introduced in Chapter 12.
    • The page is captured with this statement: "Connections were not modeled; outside selected blue space."
    That statement is UNTRUE for both the ANSYS and the LS-DYNA model!!
    • It misconstrues what Figure 11–9 actually shows - "Area of the floor where connection failures were modeled"
    • More importantly: This distinction simply does not apply to the LS-DYNA model! Hulsey conflates two distinct models!
    In other words: Dr. Leroy Hulsey, as of September 06, 2017, has not understood the NIST models!
     
    • Agree Agree x 1
  11. gerrycan

    gerrycan Banned Banned

    If that were the case for NIST then they would have mentioned the K3004 beam connection to column 39 and how that would result in less expansion to the West by K3004. The do not account for it.
     
  12. Mick West

    Mick West Administrator Staff Member

    Displacement map again. Hulsey says earlier in the presentation that in his simulation expansion of the beams pushes girder A2001 against the flange of C79, making it get stuck there and not fail.
    20170911-100333-hnvps-stuck.

    That distance is 4" inches. NIST says the girder would have to move 5.5" (or later 6.25") in order to fall off the seat. Hence Hulsey, et al, consider the NIST report to be invalid.

    But later in the presentation we have what is the result of the SAP model.
    20170912-163302-spyvk.

    (east is to the right in this view)

    What does this mean? Is the girder not part of the floor? If the floor has moved right 2", and the girder has moved 4" to the left relative to the column (as in the animation above), then does that mean that the column has "moved east" 6"?

    Hulsey says:


    Then we have this oddly smooth displacement map, supposed the output of some Abaqus model:
    20170912-165335-hvyil.
    Is this indicating the "floor" moving? No, here Hulsey says column 79 is moving.


    20170912-163931-o0d03.



    The then compares these two figures of floor movement to NIST's 5.5"
    20170912-165444-s2e3x.

    The problem is they are measuring radically different things. The SAP and ABAQUS seem to be measurements of the region around Column 79 relative to a "thermal centroid" near the lower middle of the plan. The NIST figure, on the other hand is a measure of the relative movement of the 79-44 girder relative to column 79. That would be the same as the approximately 4" (west) movement that Hulsey himself found in the more detailed model.

    It seems like in Hulsey's models the concrete, the beams, the girders, and the columns, have all been glued together in a homogenous slab where nothing moves relative to anything it is in contact with, so no connections are ever broken, things just expand and move out of the way. Columns bend (or move) several inches away from their positions. If that's the case, then what's the purpose of the simulation of the motion of the girder relative to the beam?

    This seems impossible for a number of reasons - for one the steel and the concrete have very different coefficients of thermal expansion (7.78e-06 for steel, 5.9e-06 for concrete - dolomite aggregate, Hulsey slide 68). For another they heat at different rates, so the steel will heat and expand quicker than concrete, and smaller beams will heat quicker than thick girders and columns. This is seen in the temperature distribution that Hulsey says is being used:
    20170912-174006-z3oyc.


    So this homogenous slab approach does not seem plausible. Even if it was, the comparison of the "floor" movement with a relative girder/column movement is not one that makes any sense.
     
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  13. gerrycan

    gerrycan Banned Banned

    The first example that you show shows a forced condition (expansion +40%) to get a NIST type failure mechanism. The result is no failure because of the sideplate. On drawing 9114 you can see where the stiffener is and the 3/4" setback.
    So the East bottom of the flange has about 1" or so to travel to the C79 flange face. The West flange has about 1.3/4" approx.
    On the actual AFU analysis of this on page 43 of the pdf, you can see that the east side of the flange is contacting the C79 flange. It's stuck.
     
  14. Tony Szamboti

    Tony Szamboti Active Member

    I most certainly did not agree that Leroy Hulsey's conclusion is invalid. In fact, I stated the opposite and explained how he would have come to that conclusion in post #323.

    If the columns never got hot enough to fail then the only way fire could cause a problem is for dislodgement of horizontal members removing lateral support for a significant number of stories (at least five in most cases) to cause the column(s) to be slender enough to buckle and fail. Once you include the items they ignored and omitted the NIST analysis could not show it happened between columns 44 and 79, and every other situation in the building was even less likely to have it occur. It is clear that it is groping at straws trying to say the building collapsed due to fire once you understand these details.

    The temperatures Hulsey used on the structural members involved were also worst case for the NIST simulation, so it is nonsense trying to claim any other combination of temperatures may cause it.
     
    Last edited: Sep 12, 2017
  15. Mick West

    Mick West Administrator Staff Member

    How do you figure that?
     
  16. Mick West

    Mick West Administrator Staff Member

    @Tony Szamboti, can you address my post 492, above,regarding the homogenous slab. Is Hulsey actually saying there's no movement at any of the connections?
    [​IMG]
     
  17. gerrycan

    gerrycan Banned Banned

    Hope you're not attributing that statement to me. It's the centre of stiffness that doesn't move.
     
  18. Tony Szamboti

    Tony Szamboti Active Member

    The NIST WTC 7 report (chapter 8) explains that the reason the phenomena of a girder flange folding and allowing it to fall had never happened in previous building fires is that those buildings did not have asymmetric framing of floor beams into girders with seat connections. They said this situation (occurring at the northeast and southeast corners in WTC 7) would allow lateral travel by the girder, and with it being pushed by the asymmetrical framing during its thermal expansion, cause the girder to be vulnerable to unseating. However, we now see that couldn't actually happen if the structural items they ignored and omitted (column side plates and girder web stiffeners) had been considered and included in the analysis. All other situations in the fire affected areas (besides the northeast and southeast corners) had symmetric framing and/or knife connections, which would not allow the girder to travel laterally.

    The opportunities for horizontal member dislodgement from the columns, and any subsequent loss of lateral support for enough stories to cause enough slenderness for column buckling, due to heating from fires, were essentially nil. Therefore, no vertical collapse could have occurred due to fire. Dr. Hulsey is right.

    The only way vertical collapse could happen was for the columns to be directly weakened and the fires could not heat them enough since the columns had a heat transfer path to cooler areas. The fire simulations bear this out, as they show the columns never got hotter than 300 C. At 300 C structural steel still retains all of its yield strength.
     
    Last edited: Sep 13, 2017
  19. Jeffrey Orling

    Jeffrey Orling Active Member

    OT... How odd that the scientific work was timed to coincide with the anniversary of 9/11. What's up with that?
     
  20. Mick West

    Mick West Administrator Staff Member

    No I'm not, I'm attributing it to Hulsey who said (#492),


    So again, he shows a generic value of floor displacement relative to a center of stiffness, and compares it to a specific displacement of a girder relative to a column.

    Would you agree that's an invalid comparison?

    Would you also agree that the displace diagram appears to show ZERO local displacements, only the expansion of a homogeneous slab?
     
  21. Oystein

    Oystein Active Member

    Huh?
    If what were the case?
    Did you quote the wrong post? Because your reply in no way whatsoever references the post you quoted.
    The main parts were:
    1. Hulsey misconstrues how NIST modeled connections inside and outside a certain area in the eastern part of the 16-story ANSYS model of Chapter 11. In particular, the claim that the east wall was modeled as infinitely stiff is plain wrong. NIST merely decided, with reasons stated, not to give the connections properties modeling various enumerated failure modes. In other words, they assumed that connections between wall elements would not fail. The elements, and wall as as such, however was still modelled with connections, and responding vertically and laterally to the stresses that came up in the simulation.
    2. Hulsey conflates the 16-story ANSYS model (Chapter 11) and the 47-story LS-DYNA model (Chapter 12) when he juxtaposes Figure from either Chapter and writes about the full collapse model animation that NIST did not model connection failures west of a certain line. This is plain WRONG.
    Both errors, which occupy a total of 4 or 5 slides, demonstrate that Hulsey to this date does not understood what, how and why NIST modelled what they modelled. This is cause for grave concern. Like you, like AE911Truth, he concentrates on one detail, while demonstrating incompetence on the global picture.
     
  22. Oystein

    Oystein Active Member

    As a matter of fact, you DID agree that Leroy Leroy Hulsey's conclusion is invalid in post #323 where you wrote:
    "Difficult" <> "Impossible".
    Post #323 goes on not talking about what Hulsey did in his study, but what you think about other studies, and what your base belief is about buildings (that highrises cannot collapse from fire, period). By inputting this FALSE premise you are certain to arrive at the FALSE conclusion - but you failed to show how Hulsey's study actually supports Hulsey's claim. Instead, you employ a subjunctive: "...how he would have come to that conclusion..."
    "Would" <> "Did"
     
  23. Oystein

    Oystein Active Member

    "girder flange folding" is not the only failure mode that NIST considered.

    In fact, NIST found that quite a number of girders and beams lost vertical support, on several floors and several columns as well as several beams framing into girders. The other serious engineering studies found further candidates of such connection failures, involving further failure modes.

    Hulsey did not even begin to assess these multiples of multiples of floor frame failures when he refused to model fire progression entirely, and employed a heat distribution snapshot to only two floors.

    Therefore, Hulsey's most definitely did not, could not, show that fire didn't bring down WTC7.
     
  24. Mick West

    Mick West Administrator Staff Member

    Let me focus on this objection again, as I'd like @gerrycan and @Tony Szamboti to weigh in on this specifically.

    It seems that the comparison Hulsey made on this slide is incorrect:
    [​IMG]

    The NIST value (6.2" west), is the movement of the end of A2001 (the girder between Columns 79 and 44) relative to C79, due to the theorized thermal expansion of the beams perpendicular to A2001.

    The ABAQUS value (1.85" east) appears to be the movement of a composite model and includes the movement of the column, the floor slab, and the beams and girders. Hulsey says in the presentation "they move together they didn't move separately". The ABAQUS movement is relative to a thermal centroid or center of stiffness. It does not appear in this ABAQUS model that there is any relative movement between A2001 and C79, as there are no discontinuities in the displacement map:
    [​IMG]

    So if one number is a measure of local relative displacement between a girder and a column, and the other number is a measure of the movement of the system as a whole, where girder and column move together, then how can a comparison be valid?
     
    Last edited: Sep 13, 2017
  25. Oystein

    Oystein Active Member

    The calendar days Sept 11+12 are the two days in the year where reporting of 9/11 related stuff reaches the largest audience.

    By presenting FALSE conclusions just days before those days, Gage makes sure that a measured and truthful response is not ready during the two days of maximum attention.

    This is a Propaganda trick, plain and simple. It's understandable if you put yourself in Gage's shoes, but ethically questionable in Hulsey's case, particularly given that solicitation for MONEY was intertwined with the promise, completely broken as we see today, that Hulsey would keep his study transparent throughout the process, such that the public stayed informed of its progress the entire time; and the promise, also broken thus far, that all data would be made public.
     
  26. deirdre

    deirdre Moderator Staff Member

    a read a bit of Chapter 8 since Tony brought it up, and it says there were no sheer studs, and they got this from structural drawings "Cantor 1985".. I don't want to watch an hour long video again, did Husley say why he thinks there are sheer studs?
     
  27. Mick West

    Mick West Administrator Staff Member

    Partly answering my own question, back on October 2106 Hulsey gave a talk with the same displacement slides as above. At the end of the talk he was asked a question that gives some indication of the state of the research, at 46:05



    So basically at that point they have not even modelled the motion of the girder relative to the column. Yet they still made a huge point of comparison of composite free-floating slab expansion with the NIST relative motion of the girder to the column.

    So his comparison (1.85" east vs. 6.2" west) was utterly meaningless in 2016, and still meaningless today because he's just saying the exact same thing, with the same slides, as he said in 2016.
     
    Last edited: Sep 13, 2017
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  28. gerrycan

    gerrycan Banned Banned

    @mick Do you think that UAF were right to include and account for the floor system in their model ?
    NIST did not.
     
  29. Oystein

    Oystein Active Member

    What the...!??
     
  30. Mick West

    Mick West Administrator Staff Member

    NIST included the floors, Hulsey has included them in a different way.

    Are you following my objection here? It seems like he included the floors so well that nothing is moving relative to them. You know that makes no sense. It also makes most of his presentation (and all your work) regarding the side plates, stiffener plates, and beam buckling irrelevant.
     
  31. gerrycan

    gerrycan Banned Banned

    I see exactly what your objection is. If the floor system moves as a whole to the East at C79 relative to to centre stiff point, or indeed the column does then that has to be translated as, for example, movement of the girder relative to the column in order to be compared on a like for like basis.
    I think the key phrase from Dr Hulsey is that we are looking at a week or so worth of examples from a 3 year game. And we are looking at them in what seems like a very mixed and matched way. It's difficult to make wholesale judgements on so little info, without context.
     
  32. Mick West

    Mick West Administrator Staff Member

  33. gerrycan

    gerrycan Banned Banned

    So you are claiming to have debunked the UAF study ? This should be good. Fire away.
     
  34. Oystein

    Oystein Active Member

    Rule of "So": No, you misconstrue.

    We have debunked that the specific claim "Fire did not and could not have caused the failure of this building" follows from the study. You already agreed to this, remember?

    This does not mean that the entire study is debunked, as it may or may not turn out that it raises valid objections to NIST's results re a certain single connection.
     
  35. James Ice

    James Ice New Member


    Tony Szamboti wrote a nice thing about how Hulsey was justified in saying what he said, also going into the acknowledgement of the validity of the objection that strictly speaking fire might not be ruled out as a cause.

    Perhaps you are aware of the philosophy thing where it is impossible to prove that you are not just a brain in a vat (as it often goes). You cannot prove that this world you are experiencing is real. Well, this is more or less on the same level as the objection that Hulsey has not proved that fire could not have caused the destruction of WTC7.

    You may as well say, one cannot prove that I am a brain in a vat, and this invalidates completely the presentation and the study.
     
  36. Ph_

    Ph_ Member

    This is called Russell's Teapot. Your reasoning is flawed.

    So Hulsey needs to prove his point, not shift the burden of disproof to us.
     
    • Agree Agree x 2
  37. gerrycan

    gerrycan Banned Banned

  38. Mick West

    Mick West Administrator Staff Member

    This whole seemingly false comparison seems to go back even further, to October 2015:

    Source: https://youtu.be/R-zPna-OI70?t=30m10s

    20170913-134646-gi305.


    Again, this appears to be a global absolute movement, not a local relative movement. It's the relative movements that cause connection failure.
     
    • Agree Agree x 1
  39. Mick West

    Mick West Administrator Staff Member

    Do all the other problems mean nothing to you? You asked me earlier if I knew about the C79 change of direction. Is this no longer relevant?
     
  40. benthamitemetric

    benthamitemetric Active Member

    One interest point--while there is no singular diagram of the unseating of girder a2001 in the NIST reports, NIST's technical briefing from 11/19/08 contains a simple drawing of the unseating on pg. 33):

    upload_2017-9-13_14-37-29.

    While certainly not proof that NIST properly modeled this connection correctly in its detailed sim, this drawing does include side plates and shows the girder clearing them. Whether this was possible (strictly from a side plate trapping sense) in the real world seems to me to be entirely a product of two factors (assuming the eastmost beams were expanding and pushing the girder to the west): (1) what was the average temperature of girder a2009 at the time of alleged dislodgement, and (2) regardless of its average temperature at such time, had girder a2009 previously suffered damage from the fire (e.g., had it already buckled or substantially sagged and then started cooling). We don't know the answers re these considerations in respect of Hulsey's study yet. I don't think we really know them in real exacting detail in respect of NIST's study, either, but I made be mistaken in my recollection on that point.

    Re the issue summary thread--

    Mick--I would also note that the slides Hulsey used to dismiss Arup and WAI's studies out of hand lack support. For Arup, Hulsey relied on the same error Tony has made here re dismissing Arup's collapse initiation model due to a flaw in Nordenson's subsequent hand calculations. For WAI, he dismisses the study on the bare assertion that the fire temperatures used in their primary model were too hot (even though he didn't do any independent fire modeling). He also does not address the fact that WAI received from Arup copies of iArup's girder failure models and confirmed them.
     
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