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Challenge: Demonstrate Sagging floor Trusses Pulling in Perimeter Columns

enik

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I see Gamolon has issued a challenge in another thread. I will offer an even simpler one. Show with your own FEA or calculations how the perimeter columns of WTC 1 were pulled in by up to 54” by sagging floor trusses.

Bonus, demonstrate how this instability caused the initiation sequence for collapse of WTC 1.
 
enik said:
I see Gamolon has issued a challenge in another thread. I will offer an even simpler one. Show with your own FEA or calculations how the perimeter columns of WTC 1 were pulled in by up to 54” by sagging floor trusses.

Bonus, demonstrate how this instability caused the initiation sequence for collapse of WTC 1.
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I'm wondering how it really matters? If the core failed first, OK.

The NIST was tasked to establish a probable collapse scenario and recommend changes to help improve occupant safety.

Tell you what. Use their criteria and produce a better report.

Is this score a point thing or is there really some purpose? You might note, I answered the Gamolon challenge. ;)
 
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enik said:
I see Gamolon has issued a challenge in another thread. I will offer an even simpler one. Show with your own FEA or calculations how the perimeter columns of WTC 1 were pulled in by up to 54” by sagging floor trusses.

Bonus, demonstrate how this instability caused the initiation sequence for collapse of WTC 1.
Click to expand...

Its been done. Its also been demonstrated within the actual structures in question with pictures taken by the NYPD helicopter that show the sagging trusses.
For reference please look through the NIST reports on the towers.

Now if I were disputing the NIST FEA and other research then I would be interested in producing my "own FEA or calculations" and comparing them to the NIST reports. However, I am not disputing the NIST FEAs and other research, so that would be a job for those who do.


Can you think of anyone who disputes the NIST works who might be in a position and who has the education and knowledge to produce such FEAs and other research, enik?
 
It is a simple analysis to verify the NIST report for WTC 1. Don't put anything more into it.
 
enik said:
I see Gamolon has issued a challenge in another thread. I will offer an even simpler one. Show with your own FEA or calculations how the perimeter columns of WTC 1 were pulled in by up to 54” by sagging floor trusses.

Bonus, demonstrate how this instability caused the initiation sequence for collapse of WTC 1.
Click to expand...

Done. Usmani (Scottish structural engineer) shows that floor membrane tension for a three story WTC1,2 fire, even at relatively low temperatures (400C) and without plane damage is one cause of the perimeter columns failure.
Report done in 2003, before the NIST reports.

http://www.era.lib.ed.ac.uk/bitstream/1842/1216/1/WTCpaper.pdf
 
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enik said:
Are you speaking for Usmani personally? Can you get him to come to this forum and support his report?
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Watch them goal post fly. I don't think Gamolon would mind if you posted someone elses paper. :p
 
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enik said:
It is a simple analysis to verify the NIST report for WTC 1. Don't put anything more into it.
Click to expand...

Once AGAIN, since I do not dispute the NIST report, then I do not have any impetus to redo all the research that NIST did. I am not an engineer though I can follow much of what is discussed in engineering papers and so I personally am unqualified to do such research myself.

Those who do dispute the NIST report conclusions otoh DO have impetus to redo this research, so I will leave it to those who dispute NIST to do such research.

What I find odd is your continued attempt to get a debunker to do the work and research that you should be doing.
 
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enik said:
Are you speaking for Usmani personally? Can you get him to come to this forum and support his report?
Click to expand...

BA posted a link to his report. Do you suppose that Usmani would have published something he did not believe in? Is that why you now seem to require that he come on this internet forum and specifically support it?
 
enik said:
I see Gamolon has issued a challenge in another thread. I will offer an even simpler one. Show with your own FEA or calculations how the perimeter columns of WTC 1 were pulled in by up to 54” by sagging floor trusses.

Bonus, demonstrate how this instability caused the initiation sequence for collapse of WTC 1.
Click to expand...
Can' you prove your statement without asking questions?
Inside Job Evidence is in the Physics of WTC #1
Click to expand...

The perimeter sagged in 54 inches, with is seen. Does it matter why it sagged in? Must of been under some load.

But how will you back in CD? Something that did not happen on 911? Why ask questions, why delay your big presentation of ...
Inside Job Evidence is in the Physics of WTC #1
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You go first, show how CD did it. Better hurry, 11 years of nonsense, about time for some action.
 
jaydeehess said:
BA posted a link to his report. Do you suppose that Usmani would have published something he did not believe in? Is that why you now seem to require that he come on this internet forum and specifically support it?
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I figured someone would link to Usmani's paper. That is why I specifically said in the topic "Show with your own FEA or calculations." This shouldn't be any problem for any debunker. If someone invites Mr. Usmani and he decides to come over to the forum, I would be happy to talk to him about his analysis. Maybe he could forward me his code since I also have ABAQUS.
 
enik said:
I figured someone would link to Usmani's paper. That is why I specifically said in the topic "Show with your own FEA or calculations." This shouldn't be any problem for any debunker. If someone invites Mr. Usmani and he decides to come over to the forum, I would be happy to talk to him about his analysis. Maybe he could forward me his code since I also have ABAQUS.
Click to expand...

Jesus then all this thread is, is some silly attempt at reversing the burden of proof?
 
Show with your own FEA or calculations how the perimeter columns of WTC 1 were NOT

enik said:
... "Show with your own FEA or calculations." This shouldn't be any problem for any debunker. If someone invites Mr. Usmani and he decides to come over to the forum, I would be happy to talk to him about his analysis. Maybe he could forward me his code since I also have ABAQUS.
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Show with your own work how your statement is true.
Inside Job Evidence is in the Physics of WTC #1
Click to expand...
Show the physics that is evidence of the Inside Job. 11 years, what is stopping the big day? You could join Balsamo and rule the world of 911 truth, a fantasy in the minds of a few.

The thin perimeter was actually the exterior "core" of the WTC, responsible for half the load, or close to half the load.
Why did the chief structural engineer not support the crazy claims of 911 truth? Why does Robertson understand the WTC collapse without having to do one calculation? Robertson does not have to do any calculations to see your CD claims and inside job claims are nonsense that need no rebuttal.


Show with your own FEA or calculations how the perimeter columns of WTC 1 were NOT pulled in by up to 54” by sagging floor trusses. Make my day.
 
beachnut said:
...Show with your own FEA or calculations how the perimeter columns of WTC 1 were NOT pulled in by up to 54” by sagging floor trusses. Make my day.
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He probably can - he is quite good at FEA...

BUT the whole argument is a strawman and follows the common truther tactic of focussing on a detail.

Reality is that both twin towers fell when the impact and fire affected levels became too weak to support the upper portion of tower and that upper portion fell. That initiation being a cascading failure.

At that point all the columns had failed. All of them.

So the core columns had failed and the perimeter columns had failed.

NIST said that the perimeter went first. There is good evidence from other researchers that the core went first. So what? there is no significance other than at detail level. The top bit of tower still fell.

The usual false claim is that if NIST got a detail wrong the rest of the NIST report is also wrong. That's "Truther logic" if you allow the oxymoron.

The only reason I have seen to support that "core led" v "perimeter" led matters is as an excuse to consider CD.

No excuse is needed - anyone wanting to propose CD is free to put forward a complete hypothesis. But no one has. So that track is dead in the water.

Plus "sagging trusses pulled in the perimeter" is an implied strawman (sometimes made explicit). Why did the sagging trusses have to be a reason for anything other than starting inward bowing?

The one thing that is not in doubt is that perimeter columns did bow inwards and such bowed columns would have very little vertical axial strength. So how they got bowed is a detail which may be of interest to some people for their reasons but doesn't change the picture for the rest of us:
1) Top part of tower fell; AND
2) There has never been a prima facie case put forward for CD.
 
twinstead said:
Jesus then all this thread is, is some silly attempt at reversing the burden of proof?
Click to expand...

yes it most definitely would appear so

enik knows there are papers out there aside from NIST but is requiring that others here contribute even more research and does not want to discuss the others except with original authors.

One thong is clear though, perimeter pulling is established as contributory to collapse in these papers.
If one wishes to dispute this then asking for more research that confirms it would seem counterproductive and actually doing so would be the work of persons who simply want to add detail to the situation.
otoh if one disputes accepted fire induced collapse then it would be obvious that supporting research should accompany any claim of controlled demolition.
This, it should be noted, is only a first, neccessary, step that alone would still not prove the point. That would require that some manner of evidence be brought forth to show the existance of explosives or therm?te on the structural members identified in the cd scenario that has been detailed. It would also require evidence of that placement having been performed, who, when and how and to lesser extent, why.
 
ozeco reminds us of one very salient point, inward perimeter bowing is an observed and established fact. One would be hard pressed to demonstrate that this is the result of anything other than the also observed and established fact of large area, multi-level office fires. (unless the intent is to voyage into the land of make believe where inward bowing of perimeter columns, large office fires, and even the existance of large aircraft are said to be complicated ruses)
Thus the exact detail of how this occured is irrellevant except as a purely academic endevour.
 
ozeco41 said:
Yes...plus it will probably try to limit engineering reasoning to nothing other than FEA.

For enik FEA is the equivalent of the "Nine Dots" scenario.
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While there may be several different solutions to the problem, this one is constrained further by the requirement that inward bowing must be included because it did occur.

I am quite sure that a solution to the problem of how to fully collapse these structures from an initial point about a dozen floors from the top using explosives could be found. However one then has to rework such a solution when you add in the detail that perimeter columns must bow inward over a relatively long period at the level of initial failure.
With the addition of other details such as protection of charges from aircraft impact, fuel contamination, and office fire heat for at least one hour , it would require reworking again. It still may be possible to find such a solution but it still fails to convince due to the established, observed fact of large area, multilevel office fires that were established within seconds of thousands of gallons of liquid fuel accelerant being spread over several floors at once, versus the complete lack of observed presence of explosives.

Substitute therm?te for explosives above and repeat
 
jaydeehess said:
Thus the exact detail of how this occured is irrellevant except as a purely academic endevour.
Click to expand...
Correct.
jaydeehess said:
While there may be several different solutions to the problem, this one is constrained further by the requirement that inward bowing must be included because it did occur.
Click to expand...
Also correct.

Then the other point of my caution is easiest explained by analogy - tho' I am aware that some people have difficulty processing analogies...however.

If you build a wooden frame and hold it together using nails the nails most likely inserted by use of a hammer.

The relevant questions then are:
1) Are there nails in all the needed places; AND
2) Are those nails properly inserted.

If those criteria are satisfied we know:
A) That the user of the hammer did so competently; AND
B) calling on other workers to prove that they can use a hammer is irrelevant; AND
C) Even if the other workers are less competent with hammer wielding the frame won't fall down as a consequence of that fact.

Now, to save me doing the quoting and linking bit, read back a few posts to see where the analogy fits. :)
 
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