1. Tony Szamboti

    Tony Szamboti Active Member

    Are you saying NIST observed girder A2001 walking off its seat at column 79 at the 13th floor in their analysis?

    How could NIST have observed girder A2001 come off its seat at column 79 with the column's western side plate stopping it after just 3.6 inches of travel to the west, which is the direction NIST said it traveled while being pushed by thermally expanding beams to the east of it, and it needing to go over 6 inches to get the web off the seat?
     
    Last edited by a moderator: Sep 20, 2017
  2. deirdre

    deirdre Moderator Staff Member

    because in NISTs fire event model it did not get stuck on the side plate.
     
  3. Mick West

    Mick West Administrator Staff Member

    [Note: these animation are based on inaccurate schematics that don't match the construction drawings, left here for purposes of discussion, but see later animation]

    [​IMG]
     
    Last edited: Sep 20, 2017
  4. Jeffrey Orling

    Jeffrey Orling Active Member

    Tony, Gerry et al believe that the columns did not move one iota... and the girders expanded and in so doing the girder had to be trapped. That's a simple way of conceiving of a complex event over time with variable heat around this node. Maybe.

    Do you know the actual length of the girder? It surely needed to be smaller to get it in place. Maybe it could clear the end plates? How much bearing area did that girder require?
     
  5. Tony Szamboti

    Tony Szamboti Active Member

    It has to get stuck behind the side plate.

    The beams are heated to 600 C and the girder they frame into is heated to about 500 C according to NIST. At 500 C girder A2001 (which is 531 inches long) will expanded by about 3.6 inches. That is 1.8 inches on each side. It was only about that distance from column 79's flange at room temperature, so it can't get past the side plate.
     
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  6. Jeffrey Orling

    Jeffrey Orling Active Member

    Could it sag when heated? If not why not? If so wouldn't that change the geometry?
     
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  7. Tony Szamboti

    Tony Szamboti Active Member

    Mick, the column flanges are 4.91 inches thick, so just scaling it is obvious your side plates don't have a 1.8" protrusion like they should. The girder is also heated to 500 C which expands it against the column 79 flange. Now I can see why you don't seem to understand.

    You need to redo your drawing with the right side plate protrusion and expand the girder by 3.6 inches or about 1.8 inches per side.
     
  8. Tony Szamboti

    Tony Szamboti Active Member

    Girder A2001 would only sag about 2 inches at 500 C with its 130 kip distributed load. That shortens it by about .016 inches or .008 per side, so that doesn't prevent the trapping.
     
  9. Mick West

    Mick West Administrator Staff Member

    Okay, do you have the original plan section of this? I see Hulseys:
    20170919-181421-c9vpg.
    Which is very different to the Figure 8-21 I used:
    upload_2017-9-19_18-16-31.

    So I presume that's just schematic?
     
  10. Mick West

    Mick West Administrator Staff Member

    Different image again here:
    20170919-181956-v4yzm.

    I imagine this is old stuff, but I'd like to have a better animation.
     
  11. Jeffrey Orling

    Jeffrey Orling Active Member

    Looks like the girder would not necessarily be trapped.
     
  12. Tony Szamboti

    Tony Szamboti Active Member

    The plan view Hulsey showed is accurate. You can check it against Frankel drawing 9114. Column 79 is a W14 x 730 with 2" thick x 26" wide side plates welded to it at the 13th floor. I have attached 9114 here for you. You can look up the cross sectional area of a W14 x 730 on the Internet as it is a standard structural shape. Here is a link to a structural shape catalog http://www.nucoryamato.com/staticdata/catalog.pdf
     

    Attached Files:

    Last edited: Sep 19, 2017
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  13. Tony Szamboti

    Tony Szamboti Active Member

    It most certainly will if it is heated and expanded. NIST says it was at 500 C with the beams at 600 C. Do you think the girder could stay cool with the beams framing into it at 600 C?
     
  14. Christopher 7

    Christopher 7 New Member

    [...]
    you didn't take elongation of the girder into consideration. Although this quote is from the interim analysis, it shows that the girder would be pushing up against the column face.
    NCSTAR 1-9 Vol.1 p. 352 [PDF p. 396] http://ws680.nist.gov/publication/get_pdf.cfm?pub_id=861611

    A W14x730 column is 22.4 x 17.9 inches. The side plates were 26 inches. That leaves 1.8 inches protruding past the flange. You are using the NIST graphic which shows the side plates protruding less than they actually do. The graphic on page 31 of Hulsey’s PDF has a more accurate.

    Drawing 1091 shows that the difference in the distance from the column face from one side of the bottom girder flange to the other is 3/8”. The girder would be stopped by the side plate.

    http://911datasets.org/index.php/SFile:OQZFZY6XF4DCG6SWTREJENQFHBMHTTRV
     
    Last edited by a moderator: Sep 20, 2017
  15. benthamitemetric

    benthamitemetric Active Member

    Mick understood that he was only showing a simplified view of the net lateral displacement. The elongation and other movements within the system are really impossible to show accurately without actually having the full output from NIST's ANSYS model. This is because the girder and column would have been moving together in a complex way as the fires progressed around them over time, as I noted in more detail here. As an example of how the elongation/trapping scenario is too simple, girder A2001 was cooling at the point in time when NIST determined it became unseated. Arup also found that it could fail in the cooling phase (Arup found it could fall off the seat to the north as it cooled, in fact). If (1) girder A2001 expanded and pushed column 79 south in its heated phase and then (2) girder A2001 sagged in its heating phase and began contracting in its cooling phase, it is quite plausible that it would no longer be within the bounds of the side plates of column 79 as column 79 was pushed east by the heating phase of the girder to its west. This is why it is such an incredible shortcoming in Hulsey's work to date that Hulsey did not test NIST's actual heating model (or any actual fire progression model).
     
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  16. Mick West

    Mick West Administrator Staff Member

    Animations are good tools for communicating what happened. Of course mine is a simplification. However it should be possible to create one with the simulations. I'm surprised that Hulsey has not yet done this. It would be a great way of communicating the relative heating and motion of different parts.

    @Tony Szamboti, did you make animations of your simulations?
     
  17. Mick West

    Mick West Administrator Staff Member

    So, it would be more like:
    Sheet-9114-Col-79-animation.

    Although that's just showing relative movement, the column might move too, and that entire region of the buidling might be expanding NE as in Hulsey.
    Sheet-9114-Col-79-animation-both.

    These are just animations of what might have happened, not calculations.
     
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  18. deirdre

    deirdre Moderator Staff Member

    NIST claimed they used 1091.
    and 3 paragraphs above your NIST quote (report page 351), they said they did include side plates.
    so, apparently in their fire model the girder did not get stopped. How you would model exactly, in a simple animation the sequence of events described on those pages, without exact distances given, I don't know.
     
  19. Jeffrey Orling

    Jeffrey Orling Active Member

    How did you determine the direction / angle of movement in these animations?
     
  20. Mick West

    Mick West Administrator Staff Member

    They are just rough illustrations of what might have happened, with no consideration of how it happened. I just manually moved the pieces in the direction indicated by whichever description. NIST has a 6.25" movement that misses the side plate. Hulsey has a 2" movement roughly NW, so the second animation is a combination.
     
  21. Tony Szamboti

    Tony Szamboti Active Member

    Mick, your illustration is not just rough, it is inaccurate as you have the girder at its room temperature length. If it is at room temp then the beams would be too and there would be no lateral travel because the beams wouldn't have expanded. If the beams are hot the girder would be also.

    The girder was heated to 500 C, and at that temp it would be about 1.8 " longer on each end. The girder was 531.625" long. You know the CTE of steel at that temp.

    You need to elongate the girder to account for the thermal expansion and redo your illustration.
     
  22. deirdre

    deirdre Moderator Staff Member

    the girder did not spontaneously go from room temp to 500C in two seconds (ie. the time span of that illustration). Perhaps you can try applying an accurate 3-4 hour heating time frame in a 2 second animation, so we can see what you are envisioning.
     
  23. Oystein

    Oystein Active Member

    Nonsense. The length of the girder in Mick's animation is impossible to see, derive or measure, as you only see one end of the girder. You seem to be making baseless, unknowable assumptions about the shape of the girder, the distance between C79 and C44, and perhaps one or two more things.

    Besides, Mick's animation is not at all an attempt to accurately model, simulate or otherwise replicate either the real-world motion or NIST's or anyone else's specific model motion. It is merely an illustration of the concept "girder moves laterally relative to column, across its connection seat", to compare to a situation as Hulsey seems to have it "girder end moves together with column". A communication device.

    Without simulating how wandering fires heat up and cool down steel and concrete at different times and in different directions on many floors over a matter of several hours, you cannot pretend to analyse how the girder end "really" moved relative to the column. I like benthamitemetric's metaphor of an elaborate, complex "dance" that all the elements dance.
     
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  24. Mick West

    Mick West Administrator Staff Member

    The animation shows what would have had to happen for the connection to fail. It's not intended as a proof of what happened.

    I think one has to ask if there is any pattern of heating the entire building that would give this end result? Is it even possible to heat individual beams and girders selectively in a sequence in which this happens?

    Simply saying it does not happen if you heat the girder and the beams evenly, and the column does not move, is really only eliminating one sequence, and one that is neither realistic nor sufficiently detailed.

    And on a broader note. This is not the lynchpin of the NIST case. Sure, it's the lynchpin of the probable collapse sequence they put some time into investigating, but their ANSYS model showed multiple failures that could cause floors to collapse, not just this one.
     
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  25. Tony Szamboti

    Tony Szamboti Active Member

    You have the girder at room temp if you don't move it closer to the column than what the drawing shows, so there is no heating of the girder in your illustration.

    It is virtually impossible to have the adjacent beams heated to a high temp in order to push the girder but not have the girder at elevated temperature, so your illustration is impossible and could not have happened.
     
  26. Oystein

    Oystein Active Member


    Already answered. Read post #28.
     
  27. deirdre

    deirdre Moderator Staff Member

    isn't the point of Hulsey's study to prove this? so we need to see his data. Until then, why keep repeating something you can't prove? or why even bother to pay Hulsey 300k if you aren't going to release his data?
     
  28. Mick West

    Mick West Administrator Staff Member

    To clarify the topic, I have renamed this thread:
    Could Girder A2001 Possibly Have got Past the Side Plate on Column 79?
     
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  29. Tony Szamboti

    Tony Szamboti Active Member

    It is actually common sense. The girder was in the same vicinity as the allegedly hot beams. Do you walk in a steam room and stay cool?
     
  30. Tony Szamboti

    Tony Szamboti Active Member

    Fine, I am saying it can't and nobody here has provided a sound way it can. All that was done so far was your post of an illustration that left the girder at room temperature in an unexpanded state. That isn't possible if it was being pushed by allegedly hot beams framing into it.

    The western corner of girder A2001 was about 1.8 inches from the column flange and the side plates protruded about 1.8 inches from the column flange. As soon as the girder is hot it will be inside the protrusion and there is no way you can time it to make a difference. Why are you supporting a clearly bogus analysis? Is it that you just can't believe someone in an official capacity would do such a thing?
     
    Last edited: Sep 20, 2017
  31. Jeffrey Orling

    Jeffrey Orling Active Member

    The environment did not go from room temps to 500° or whatever instantly. The temps were slowly heating the materials of the building and those materials were responding in their own unique way... some combust... some maybe melt... some evaporate... some become elastic and sag, some expand... But they do that according to their unique physical characteristics.

    Is it possible for the girder to be pushed a bit at a lower temp... sort of gradually move as it's heated. Maybe the beams were headed before the girder and they expanded before it did? Is that possible?

    How is it possible to make such precise predictions... such as it is impossible for the girder to now slip off the seat? Does anyone know if it was fabricated at the precise length on the drawings? Aren't steel beams and so on dimensioned of of column grids and then the fabricator determines the clearances etc... such as in knife connections? A steel frame is hardly built like Japanese timber construction precision.

    No?
     
  32. Oystein

    Oystein Active Member

    Already answered. Read post #23. You assume that columns 44 and 79 never move relative to one another. As if A2001 on floor 13 and the beams to its east were the only part of the building that was ever heated, and all the rest stayed perfectly in pritine condition.

    That is obvious nonsense.

    Devastating fires wandered and roamed through many floors for hours and made the entire assembly dance an intricate dance.

    You can't know the distance between the two colums without considering the history of the fires on all floors.
     
  33. Tony Szamboti

    Tony Szamboti Active Member

    I have explained the dimensions and as soon as the girder heats up it is inside the envelope of the side plates, and the beams and girder are in very close proximity so you won't have one heating and one not heating. If the beams are pushing at all they are hot and so is the girder and it is inside the side plates. It actually is an ironclad proof that the NIST WTC 7 report has no merit and is not a legitimate explanation. It doesn't matter why they did what they did. The report doesn't explain the collapse initiation failure because there is a situation which fully precludes their hypothesis, which they seem to have ignored.

    If you really think it could happen then tell us how you think it could happen with some specificity. In other words, what had to do what for what you are trying to imagine to even have a chance of occurring?
     
    Last edited: Sep 20, 2017
  34. Oystein

    Oystein Active Member

    Posts 23 and 32. Read them! You forget the hours of fire on many floors! The rest of the building was NOT pristine! You can't know the distance between columns 79 and 44 when you ignore fire histories on all floors!
     
  35. deirdre

    deirdre Moderator Staff Member

    unless... it was already past the side plate before it heated up enough.

    Hulsey says the column moved east. NIST agrees with this, so if the column moved 2 inches east while the beams were pushing west, it's maybe possible the first edge was past the side plate. and if column 44 moved north, as Hulsey says it did that would pull the girder a bit further from the side plate. Quan (or Xaio?) were saying something about huge axial tension when things expand... I don't know if beams would produce huge tensions...

    I think the point is. We (the general public) don't know if NIST is accurate because we don't have their data, they weren't transparent. And we (the general public) don't know if your hypothetical is accurate because so far Hulsey wont release his data, he isn't being transparent.

    So far no one who (allegedly) modeled the fire event has shared their exact data with us.

    So as I see it, this whole conversation is just going to be a circular opinion fest. My opinion is 'we don't know for sure and the Truthers don't know for sure either, because only a computer model can even hope to come close to modeling a long fire event... and even then there is no way a computer can be 100% accurate because no one was in the building with a thermometer.'
     
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  36. Mick West

    Mick West Administrator Staff Member

    You can certainly have one heating a lot faster. There's two main factors:

    1) Where the fire is. It's clearly under the beams more than the girders
    2) The heated surface area to volume ratio. Everything else being equal then a skinny beam heats up faster than a fat girder.

    Here's the calculated floor 13 temp at 4:30. The girder is still mostly blue (<200)
    20170920-182158-3cxrf.
     
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  37. Tony Szamboti

    Tony Szamboti Active Member

    That couldn't happen because the beams needed to be hot to push the girder past the side plate and there is no chance the beams got hot and the girder didn't.
     
  38. Tony Szamboti

    Tony Szamboti Active Member

    It would essentially need to be one heating and one not, because as soon as the girder gets heated it starts into the side plate envelope, so what you are saying would not work. 300 C is enough to expand the girder by 2.2 inches. That is 1.1 inches per side and well within the envelope of the side plates. Even a 200 C girder can't get past the side plates.
     
  39. benthamitemetric

    benthamitemetric Active Member

    Except NIST didn't say the beams pushed the girder off the seat per se, and, as has been pointed out, the girder and the eastmost beams were cooling when the girder failed. At that time, it was the girder to the west of column 79 being heated. It seems more likely that it was resulting movement of column 79 back to the east that caused the ultimate dislodgement of girder A2001, not further absolute movement to the west of that girder. The relative heating and cooling of these elements is all readily apparent in the floor 13 heat maps that NIST provided. You have been stuck arguing against the same strawmill (a portmanteau of strawman and windmill that I coined just for you) for years.
     
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  40. Jeffrey Orling

    Jeffrey Orling Active Member

    What about the transit indicating that the building was warping? Was that also a naked eye sighting confirmed by the transit? Do we know how far out of plumb it was? Do we know where it was out of plumb? Was the entire building surveyed that day with a transit? Shouldn't we expect some manner or load redistribution and perhaps warping of the frame as a result of falling beams which destroyed part of the SW corner?

    I think after 7 hours of fires and some falling debris in the morning... the frame would hardly be expected to be rigid and true.