Merged Why WTC7 should not have collapsed

[funk de fino]

Bill Manning is not a "truther".

I have seen other truthers use Bill Manning's words to bolster a false claim. You have copied them. Do you have anything original?

Care to admit your or Bill's mistake?

 

[funk de fino]

Perhaps you could provide some links to the reports containing the data from these "forensic" investigations and inspections.

Perhaps you could do this yourself? I have given you a name already of someone who backs up the claim I made. You only need to contact him and ask him for clarification and any documents he may have supporting his claims. He may also give you contacts for people who carried out the examinations. You may want to contact the demolition companies that were involved and see if they have any info or are willing to talk to you about it.

I know for a fact you will do none of these though. Same old pathetic MO. Handwave everything that contradicts your false claims and expect someone here to do all your legwork for you.

 

[funk de fino]

heres one study of a piece of steel from WTC7

http://wtc.nist.gov/media/AppendixC-fema403_apc.pdf

heres a description of the steel coollection and inspection process

http://www.civil.columbia.edu/ce4210/FEMA_403CD/html/pdfs/403_apd.pdf

 

[Dave Rogers]

[Why do you call this an "extreme over-statement"? - JJ]

Because it will not "always be conjecture"; it's already far more than that. It's a fully formed hypothesis that agrees with all the available evidence, and so far the only hypothesis that agrees with the available evidence, your continuing attempts to claim that it's unfounded because of the lack of one class of evidence notwithstanding.

We await Colin Powell's promised White Paper evidence in support of the latter, unsubstantiated conspiracy theory.

It's informally known as the 9-11 Commission Report.

Dave

 

[GlennB]

Perhaps you could provide some links to the reports containing the data from these "forensic" investigations and inspections.

Wouldn't it be wise to do a thorough search yourself before making claims that are so easily debunked that you end up looking foolish?

 

[GeeMack]

You are 100% right that when building a tower you start with the primary and secondary structure and then add the tertiary structure at the end. If a fire occurs and affects the tertiary structure, evidently the primary and secondary structure are unaffected unless the fire also damages them. The question is only how? The loss of tertiary components cannot damage them, as suggested by NIST in the WTC7 report. They make a lot of noise about the tertiary structure, floor elements fitted last at construction, being damaged by fire, but they cannot destroy the more solid secondary and primary structure. Anyway, NIST has asked for comments and I look forward to their reply in due course.

Thanks for your interest in this matter.

You've clearly mistaken my ridicule of your idiotic notions about building construction for interest.

 

[Dave Rogers]

Pls note introduction of problem in Comment No. 1 below. Below is a draft of submittal of comments to NIST and JREF members are welcome to comment prior my sending it to NIST.

You appear to have omitted to make the primary points listed in the opening post of this thread. Would it not be more in line with your specific objections to the NIST report if you (a) highlighted the implausibility of global collapse ensuing from the failure of a single primary part (section 8 in your OP); (b) highlighted the role of friction between different parts of the structure in absorbing sufficient energy to arrest the collapse (points 7/8 in your OP) and (c) made it clear that, to use your own words, "The WTC7 destruction can be explained by Controlled Demolition of internal columns at the ground, i.e. multiple, intentional local failures"? I think that adding these three points would give NIST a clearer understanding of the origin and nature of your objections.

Dave

 

[Heiwa]

You appear to have omitted to make the primary points listed in the opening post of this thread. Would it not be more in line with your specific objections to the NIST report if you (a) highlighted the implausibility of global collapse ensuing from the failure of a single primary part (section 8 in your OP); (b) highlighted the role of friction between different parts of the structure in absorbing sufficient energy to arrest the collapse (points 7/8 in your OP) and (c) made it clear that, to use your own words, "The WTC7 destruction can be explained by Controlled Demolition of internal columns at the ground, i.e. multiple, intentional local failures"? I think that adding these three points would give NIST a clearer understanding of the origin and nature of your objections.

Dave

Dave,

thanks for comments. At present I just concentrate on Chapters 11 and 12 of the NIST WTC7 report and point out some errors and omissions there.

If NIST does correct FEA analysises and reports all findings of these analysises in Chapters 11 and 12, NIST should find that local (small) failures due to heat/fire/thermal expansion do not cause a final proximate failure (of, e.g. a primary element) before and leading to collapse. That finding should then produce some interesting discussion what could have caused the collapse, in the opinion of

Heiwa

 

[funk de fino]

Heiwa

Do you think progressive collapse is an impossible scenario in this world?

 

[Dave Rogers]

thanks for comments. At present I just concentrate on Chapters 11 and 12 of the NIST WTC7 report and point out some errors and omissions there.

At the very least, though, you should point out to NIST the role of friction between components in arresting progressive collapse. If your OP is correct, then this is an aspect they have not properly considered. It seems to me that this is the most crucial omission you should be pointing out.

Dave

 

[Heiwa]

Heiwa

Do you think progressive collapse is an impossible scenario in this world?

Yes, at least to 3D steel structures with multiple primary structural columns spread around carrying the load of and supported by secondary structure - slooping and horizontal beams - and with tertiary structural floor elements attached to the horizontal beams only subject to local damage somewhere. That structure will not collapse progressively due to the local failures due heat or whatever and then due to gravity. No way.
Only way to knock down such a structure is CD applied to a majority of primary columns, e.g. the internal ones. Then the whole thing collapses ... as seen on 9/11.

 

[chillzero]

That structure will not collapse progressively due to the local failures due heat or whatever and then due to gravity.

Why not?

 

[Dave Rogers]

Yes, at least to 3D steel structures with multiple primary structural columns spread around carrying the load of and supported by secondary structure - slooping and horizontal beams - and with tertiary structural floor elements attached to the horizontal beams only subject to local damage somewhere. That structure will not collapse progressively due to the local failures due heat or whatever and then due to gravity. No way.

Again, I feel you should add these remarks to any response you make to the NIST report. Without an answer to these crucial points you raise, any revision of the report is hardly likely to explain the collapse to your satisfaction.

Dave

 

[Heiwa]

At the very least, though, you should point out to NIST the role of friction between components in arresting progressive collapse. If your OP is correct, then this is an aspect they have not properly considered. It seems to me that this is the most crucial omission you should be pointing out.

Dave

Not at all. The NIST WTC7 report simply fails to identify the critical failure that initiates the collapse. And no critical failure = no collapse.

It seems some local failures occurred around primary structural element column 79 of WTC7 including very serious ones; the secondary structural beams attached to column 79 at several floors were disconnected but how (is not known)? There are four beams at every floor and NIST suggest that 12 were disconnected. Strange! The connections are very strong. Cannot fail due to thermal expansion. And then column 79 would fail due buckling! But even that that is not serious! The unfortunate column just drops down and all loads on it drops down with it or slips off. No global collapse of the rest of the WTC7 structure. No friction required there. No parts rubbing against one another.

You mix up with WTC1, where the complete upper block is assume to drop down and to get destroyed and the floors get entangled. Plenty of friction there, to stop further destruction.

But do not worry. You'll get a copy of my submittal to NIST in due course. You really inspire me to do it.

 

[Mark Felt]

Heiwa, what's the difference between a critical failure and a local failure? You haven't distinguished this that I can see.

 

[Heiwa]

Why not?

Read #184 again. The local failures due heat will not affect primary structure, but even if one primary column fails, due to buckling, nothing serious happens elsewhere. Basic. Wake up. Study strucural damage analysis. Fascinating subject.

 

[Heiwa]

Heiwa, what's the difference between a critical failure and a local failure? You haven't distinguished this that I can see.

I do that just now in my submittal though to clarify. So I can quote from it (as I am working):

Comment No. 1: In structural damage analysis - as opposite to structural design analysis - it is not load paths of the intact structure that is of interest, but the path of failures from the first small local failure due to a known cause (e.g. fire) to the end of destruction including all structural failures in between as a consequence of the first, small failure. Such a damage analysis shall identify the critical failure in the path, i.e. could that critical failure be avoided; the destruction would have been arrested there. Most local failures in steel structures luckily do not progress to create a critical failure that causes the complete structure to globally collapse. The destruction is generally arrested long before that.

...

Actually, if the LS-DYNA software can produce what is suggested, it should be able to simulate all the structural conditions from (A) the completely intact, prior fire, cold condition, (B) all the part damaged conditions due local failures with still intact structure left including (C) the critical failure condition, when further destruction starts by gravity alone, and not least, (D) the end condition, when all structural parts or sub-assemblies are disconnected in the rubble at equilibrium on the ground.

Thanks for your comment

 

[Heiwa]

Again, I feel you should add these remarks to any response you make to the NIST report. Without an answer to these crucial points you raise, any revision of the report is hardly likely to explain the collapse to your satisfaction.

Dave

Don't worry. It will be be clear in the submittal. Just now I just describe the errors and omissions in the draft report.

Heiwa

 

[Heiwa]

You've clearly mistaken my ridicule of your idiotic notions about building construction for interest.

I am just polite thanks to my Japanese upbringing. Sayonara bakayaro!

 

[Grizzly Bear]

Heiwa

Do you think progressive collapse is an impossible scenario in this world?

He stubbornly applies a standard apparently regardless of the design parameters. I've asked him several times and he's made no effort to elaborate why he applies a defacto standard to all structures with no regard for how the design affects the collapse mechanisms.