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WTC7 and the girder walk-off between column 79 and 44

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gerrycan said:
sure, watch the videos.
http://www.youtube.com/watch?v=qGe0E9cjUbI
http://www.youtube.com/watch?v=AvRKZO5o_dA&feature=related
http://www.youtube.com/watch?v=-Zsp0UcgMzs&feature=related

And who is 'we'?
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None of this has anything to do with the following post of yours.

gerrycan said:
Yes, foreknowledge is an issue, i agree. Fire doesnt bring buildings like this down, and certainly not predictably, or to a countdown.
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To which I replied here
http://www.internationalskeptics.com/forums/showthread.php?postid=8122637#post8122637

and here

http://www.internationalskeptics.com/forums/showthread.php?postid=8122648#post8122648

Why did you ignore them?

And "we" is myself and tsig.
 
gerrycan said:
I am concentrating on NISTs explanation here. I do agree that a better FEA model should be used though. As for the beam impacting the column, i dont understand where that is coming from. The beams are attached to the girder, not the column, and no one is claiming that the beams impacted the column at all. Are you confusing the girder with the beams? Also, you have things kind of the wrong way round. NIST said the plate was 11". Its a confusing topic, and easy to get the wrong way round.
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Apparently I am confusing them, my apologies - I am coming at this as a Mechanical Engineer and not a Structural Engineer. I still don't understand how 0.5" can make a difference. Also, it would not just be a straightforward FEA, you would need to do a Monte Carlo taking into account variations from other impacts to the structural members, plus possible material variations, wouldn't you?

Also someone noted earlier that the "as built" may have been different than the drawings you were looking at.

I did bring up to Christopher7 that he should take this to NIST, and this has also been pointed out to you, and so I reiterate that point. Chris said it would have to be from a certified Structural Engineer, although I don't understand why that would have to be. There is one structural engineer in the AE911Truth organization, you can go through him.
 
gerrycan said:
I know it's a crazy idea to think that these beams could all go to 600 deg in a few seconds and uniformly at that, but hey, that's NIST for ya.
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This simply betrays your lack of understanding of such models. The only good reason to make it that slow is the avoidance of dynamic effects. What would you do, have it take several hours as in real time?
 
gerrycan said:
yes, it would make the distance reqiured more like 9.4". you can see it on frenkel 1091 on the bill of materials. The sideplates are a different issue.
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The seat was not square to the column, but the stiffener plate was. As the girder moved it moved away from the relatively thin stiffener plate. The diagram Chris7 posted here illustrates the point.

And, incidentally, thermal expansion has long been recognised as a serious hazard in building fires.
 
gerrycan said:
maybe you should look at the drawing for yourself, and then say why you think it would or wouldnt change the walk off required.
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@gerrycan:
Several of the other members are letting you shift the burden of proof. I won't.

If you are making a claim it is not an answer to tell others to do your work for you. You are questioning the "walk-off" mechanism. It is your problem to identify what your problem is. No apology for the circular definition I used to get the message across.

That bit said the next issue you seem to be facing is that you are making the same mistake as Cristopher7 has repeatedly made. You seem to be considering the collapse initiation as if it was the result of a single factor. That factor being linear expansions(/contractions?) due to temperature changes. If you are making that mistake you need to consider all the factors in play. If you aren't then my word of caution can simply act as a reminder. C7 has not come to grips with the issue - you could read the recent pages of the thread to inform yourself of what has been discussed.
 
GlennB said:
The seat was not square to the column, but the stiffener plate was. As the girder moved it moved away from the relatively thin stiffener plate. The diagram Chris7 posted here illustrates the point.

And, incidentally, thermal expansion has long been recognised as a serious hazard in building fires.
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Your statement makes 0% sense. The plates are welded to the GIRDER not the COLUMN.
And yes thermal expansion has been around for quite some time, and recognised as a hazard, i agree, i will reply more fully when i get time.
 
GlennB said:
Just for clarification - The NIST document titled "Final Report .... 7" only runs to 80-odd pages.

Whereas NCSTAR 1-9 (Nov 2008, labelled "Final report..." on the NIST website, but not in the doc itself)) does, indeed, talk about the girder being rocked off its seat by a collapsing floor.

Which document are you referring to as "the final report". Obviously I might be looking at the wrong one or an old version.
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The final report on WTC 7 is in 4 volumes. Here are the links:
1-A reference page
http://wtc.nist.gov/NCSTAR1/NCSTAR1Aindex.htm

1-A direct
http://wtc.nist.gov/NCSTAR1/PDF/NCSTAR%201A.pdf

1-A & 1-9 reference page
http://wtc.nist.gov/NCSTAR1/NCSTAR1-9index.htm

1-9 Vol.1 direct
http://wtc.nist.gov/NCSTAR1/PDF/NCSTAR 1-9 Vol 1.pdf

1-9 Vol.2 direct
http://wtc.nist.gov/NCSTAR1/PDF/NCSTAR 1-9 Vol 2.pdf

1-9A direct
http://wtc.nist.gov/NCSTAR1/PDF/NCSTAR 1-9A.pdf

ETA: Correction - NIST has redirected those links to the main page. Clicking on Publications takes you to:
http://www.nist.gov/el/disasterstudies/wtc/wtc_finalreports.cfm

The 2008 report is at the bottom of the page.
 
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gerrycan said:
Yes, foreknowledge is an issue, i agree. Fire doesnt bring buildings like this down, and certainly not predictably, or to a countdown.
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Fire does bring down a building exactly like this! At best you are spreading a lie, the BIG lie kind of lie.

Countdown? lol, how do you make up this stuff? You are a thermite supporter. No thermite was found, Jones made it up. Why are you so gullible? Why is Gage so stupid on 911 issues, unable to do any studies with his over 1,000,000 dollars he has scammed from nuts on 911?
 
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Christopher7 said:
The final report on WTC 7 is in 4 volumes. Here are the links:
1-A reference page
http://wtc.nist.gov/NCSTAR1/NCSTAR1Aindex.htm

1-A direct
http://wtc.nist.gov/NCSTAR1/PDF/NCSTAR%201A.pdf

1-A & 1-9 reference page
http://wtc.nist.gov/NCSTAR1/NCSTAR1-9index.htm

1-9 Vol.1 direct
http://wtc.nist.gov/NCSTAR1/PDF/NCSTAR 1-9 Vol 1.pdf

1-9 Vol.2 direct
http://wtc.nist.gov/NCSTAR1/PDF/NCSTAR 1-9 Vol 2.pdf

1-9A direct
http://wtc.nist.gov/NCSTAR1/PDF/NCSTAR 1-9A.pdf

ETA: Correction - NIST has redirected those links to the main page. Clicking on Publications takes you to:
http://www.nist.gov/el/disasterstudies/wtc/wtc_finalreports.cfm

The 2008 report is at the bottom of the page.
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Thanks for those links C7 - I had misplaced my own index document - this info now in my files as "NISTlinkscourtesyofC7" - being an ancient age computer user I still prefer not to have blank spaces in file names. I have grown out of the 6 and 8 character limits :rolleyes:
 
Christopher7 said:
ETA: Correction - NIST has redirected those links to the main page. Clicking on Publications takes you to:
http://www.nist.gov/el/disasterstudies/wtc/wtc_finalreports.cfm

The 2008 report is at the bottom of the page.
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Thanks, and that's the version I have and the one tfk was referring to when you told him he wasn't looking at the "final report". And p353 does - as tfk pointed out - talk of the girder being rocked off its seat. So why did you correct him on that?
 
GlennB said:
Thanks, and that's the version I have and the one tfk was referring to when you told him he wasn't looking at the "final report". And p353 does - as tfk pointed out - talk of the girder being rocked off its seat. So why did you correct him on that?
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Far be it from me to speak for C7. However, I bear some responsibility for this. Back in post #26, C7 quoted vol. 2, p. 527:

NIST said:
A girder was considered to have lost vertical support when its web was no longer supported by the bearing seat. The bearing seat at Column 79 was 11 in. wide. Thus, when the girder end at Column 79 had been pushed laterally at least 5.5 in., it was no longer supported by the bearing seat.
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I pointed out that this passage describes a different analysis than the passage in Vol. 1. I think that C7 concluded that NIST's 'final answer' is that the girder connecting columns 44 and 79 walked off its seat solely due to thermal expansion of the beam, which pushed it. Various other sentences in Vol. 2 can be read in that way.

Considering that the same page (527) says that "the girder between Columns 44 and 79 buckled and walked off the bearing seat..." (emphasis added; as always, context matters) -- and trying to apply common sense -- I don't think that is right. I'm by no means qualified to make out all the details of the analysis, but I can see the dangers of cherry-picking sentences here and there from a series of model descriptions.
 
Don't both the 12" and the 11" figure come from the same report?
 
gerrycan said:
I'm just saying that the reason for the collapse is not the one that NIST claim because it is physically impossible, it follows then that this should be reinvestigated, in order to establish what could have caused this. Would it be reasonable for example, to expect NIST to test for explosives/residue, even if it were only to rule this out as a possible cause? After all, explosives have brought down way more steel buildings than fire ever has.
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More people die from natural causes then from being shot. Would it be reasonable to assume that someone who is dead and has a bullet wound in his chest died of natural causes?
 
gerrycan said:
Depends, how hot did it get? And NIST say that these beams were heated uniformly in their analysis, so their expansion would be proportional to their length. I know it's a crazy idea to think that these beams could all go to 600 deg in a few seconds and uniformly at that, but hey, that's NIST for ya.
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Citation needed.
 
tsig said:
Don't both the 12" and the 11" figure come from the same report?
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No, the 11" was what NIST said in the final report. The 1' 0" was what was on the drawing that NIST got its information from.

That is not an innocent mistake IMnsHO.
 
I'm a little disappointed that you guys seem back to discussing minutia. If the video guy returns, I too would appreciate the answer to ozeco41's question.

Why is he producing these videos? What is the motivation, and what is the desired outcome of producing these videos?

More succinctly - What does success look like to gerrycan?
 
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000063 said:
Citation needed.
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He's referring only to the way the model was run. There was no need - in the model - to heat the metal slowly. In his ignorance he is proposing that the actual beams heated in such a manner and that the NIST model was mimicking how they heated in real life :rolleyes:
 
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