OOS Collapse Propagation Model

[Dave Rogers]

Let's say the energy in the upper block was double that needed to crush the lower block in a column to column impact. Now let's suppose the floor truss connections were by far the weakest link and 80% of the mass of the upper block fell on the floors outside the core. The floors and the perimeter columns would be taken down easily, but only 20% of the total energy would be left to fall on the core.

This is the style of analysis called "pulling numbers out of your ***". Bazant and Zhou calculated that the energy of the upper block falling through a single storey was more than eight times that required to collapse the storey below. After falling another storey and losing one floor's worth of energy, it would then have gained another eight times the requred energy, so there would then be fifteen times the energy required to collapse the next floor. 20% of that energy - to use your made-up numbers - would still be more than enough to collapse an entire floor, let alone a single level of core columns. What you need to understand is that this wasn't a situation where the falling block had just barely enough energy to destroy the next storey down; it had a very large excess of energy, which got larger rather than smaller as it fell further. This is why the global collapse is agreed by competent structural engineers to have been inevitable once collapse was initiated.

Dave

 

[bardamu]

<groan> Bazant et al didn't examine a real-life collapse mechanism. They examined the mechanism most favouring collapse arrest. The building still came down in that study. Real life was bound, by definition, to be worse and - golly! - they came down of course.

If the floor-to-column connections were the weakest link, a column-to-column impact is not necessarily the mechanism that most favours collapse arrest.

 

[Major_Tom]

For some people every sentence written by Dr Bazant is treated as gospel. This thread has been slow moving because a few comments in the OSS collapse propagations study offended some Bazant loyalists in this forum.

I was forced to write 3 reviews just to explain to the readers some of the main problems with the papers and to show what they do cover and what they do not cover. These reviews must contain some pretty provocative comments if you believe the Bazant papers contain no imperfections.

I've been trying to show the reader that these papers do not directly cover some of issues most important to the CD debate, such as:

1) The collapse initiation mechanism of WTC 1 and 2

2) Anything concerning the collapse of WTC 7, including:

a) Fall time
b) Symmetry of collapse
c) Practically instantaneous collective column failure during collapse initiation, an extremely rapid lateral failure progression wave.
d) A small, compact, organized hill of rubble remaining after the fall of WTC 7.
e) The uncanny resemblance of the collapse to a controlled demolition.
f) Accidental hastily-released eulogy by the BBC of the collapse of WTC 7.

among other features.

To me and many other people, these are the most important issues to address

Collapse initiations of WTC1 and 2 are covered in the NIST reports, and Bazant refers to the "meticulous investigation of unprecedented scope and detail, conducted by S. Shyam Sunder’s team at the National Institute of Standards and Technology" as the "proof" that confirms his own views about collapse initiation.
>>>>>>>>>>>>>>>>>>>>>

Some people are posting that I should move on to the subject of collapse initiation, but a die-hard group of Bazant loyalists have refused to admit to a single mistake or criticizm of anything within the Bazant papers. A group of posters treat the Bazant papers as if they were sent by a Deity. Not a single sentence in any of the papers should be questioned.


As for me, some of the papers contain glaring mistakes and none of the 4 papers directly addresses the issues most important to the CD question.

For example, in BL(=BVReply), how could anyone not notice that Bazant's claim cannot be true:

"4. Can Crush-Up Proceed Simultaneously with Crush
Down? It can, but only briefly at the beginning of collapse,
as mentioned in the paper. Statements such as “the columns
supporting the lower floors . . . were thicker, sturdier, and
more massive,” although true, do not support the conclusion
that “the upper floors
i.e., the floors comprising Part C
would be more likely than the lower floors to deform and
yield during collapse”
deform they could, of course, but
only a little, i.e., elastically. More-detailed calculations
than those included in their paper were made by Bažant and
Verdure to address this question. On the basis of a simple
estimate of energy corresponding to the area between the
load-deflection curve of columns and the gravity force for
crush down or crush up, it was concluded at the onset that the
latter area is much larger, making crush-up impossible. We
have now carried out accurate calculations, which rigorously
justify this conclusion and may be summarized as follows."


Yet a follower of Bazant sees nothing wrong with the apparent contradiction. Instead, they will insult me for not seeing the "perfection" within the papers.

>>>>>>>>>>>>>>>

I don't think the followers of Bazant will ever be convinced that there could be the slightest blemish within Bazant's reasoning, no matter how obviously the OOS study in the OP contradicts the divine doctrine of "crush down, then crush up".

The followers of Bazant will keep harrassing me and insulting me, while they are free claim anything about the papers that pops into their imaginations with no moderation or reality checks at all.

Bazant loyalists can derail this thread endlessly, while never admitting to the smallest error within their gospel of truth. Is there anyone insulting me who can admit that there are some errors in these papers?


For over 10 pages there are many posters who see perfect truth in Dr bazant's every word that have not been able to admit to the smallest mistake despite overwhelming evidence to the contrary

 

[sheeplesnshills]

Try stripping the branches from a tree and see if it collapses.

[/QUOTE]


Don't you understand that he was making a visual not a structural description?

 

[sheeplesnshills]

For over 10 pages there are many posters who see perfect truth in Dr bazant's every word that have not been able to admit to the smallest mistake despite overwhelming evidence to the contrary

[/QUOTE]


Then publish your paper! Stop wasting your time here.

 

[carlitos]

I've been trying to show the reader that these papers do not directly cover some of issues most important to the CD debate, such as:

Why do you keep bringing up "CD" and "Controlled Demolition?" It's confusing. Do you have evidence of such a thing, or is this some kind of tic in your writing style?

 

[ElMondoHummus]

2) Anything concerning the collapse of WTC 7, including:

a) Fall time
b) Symmetry of collapse
c) Practically instantaneous collective column failure during collapse initiation, an extremely rapid lateral failure progression wave.
d) A small, compact, organized hill of rubble remaining after the fall of WTC 7.
e) The uncanny resemblance of the collapse to a controlled demolition.
f) Accidental hastily-released eulogy by the BBC of the collapse of WTC 7.

among other features...

Mother of God... how many times do you need to be told that Bazant's group never intended to even address 7 World Trade? Gigging his work for not covering that is like calling Einstein wrong for not addressing evolution.

On top of that, pointing out how you conspiracy peddler's misunderstand Bazant is a distinct and different thing from proclaiming all his work free of error. I'm not competent enough to evaluate his math, but I sure as heck know that 1. He and his colleagues only ever intended to address the main towers themselves, and 2. As opposed to the glaring mistake made by another one of you folks above, he did indeed reference the design of the towers in his work. Those two are issues you and others don't seem to grasp.

 

[ElMondoHummus]

Don't you understand that he was making a visual not a structural description?

It's worse than that. I also was alluding to the awful misperception they have of the cores' strength, as well as the misconception they have of the design to begin with. The tree analogy harkens back to and satires Judy Wood's previous utterances, and also was meant to be a contrast between a structure that could support itself without help (the trunk) and one that could not (the core, which as everyone sane knows needed support from the floors and the perimeter defined by the exterior columns). It was a deliberate contrast of two completely different structures that I chose on purpose. And as we saw, someone blundered right into the trap and validated my contention that conspiracy fantasists completely fail to understand how the towers were built.

The cores could not stand on their own. Period. Yet, the initial response was that after stripping the floors, there wouldn't be enough energy provided by the fall of the upper segment to destroy the cores. Bull; the cores would collapse on their own if you take away the floors and perimeter columns. You don't need to hit them with anything, nor do you need to add energy to the system beyond what's required to strip the floors away. The core columns would fail on their own after that. This all shows that the energy argument was being pulled out of someone's posterior, instead of being made after careful analysis.

 

[beachnut]

...
For over 10 pages there are many posters who see perfect truth in Dr bazant's every word that have not been able to admit to the smallest mistake despite overwhelming evidence to the contrary

You can't publish anything to refute Bazant's paper; you have no experience and no background to comment on Bazant's paper as you try to back in CD.

There is no evidence for CD; you will not be about to find evidence because there was not any. No BOOMs! No left over explosives, no wires, no wireless detonators, no blast effects, no blast deaths, and no blast signs on the steel (which would be a blast effect). 8 years of failure; what will you do now?

Your paper is garbage, go publish it on Jones internet woo journal of lies and other fantasies by failed physicists and other burnt out nut cases too paranoid and insane to form rational thoughts on 911.

Your paper is perfect for Jones on-line delusion library.

... I was forced to write 3 reviews ...
...

Then publish them! I can tell you now your reviews are not going to hack it, they stink. Nice try but what engineering school did you graduate from and do they support your reviews?

I've been trying to show the reader that these papers do not directly cover some of issues most important to the CD debate, such as:

1) The collapse initiation mechanism of WTC 1 and 2
...

And you failed, you don't understand Bazant's paper, your reviews prove it. What is CD debate,there is no evidence of CD in your paper. You have no evidence, it is your delusions, you can't publish fantasy as scientific work!

2) Anything concerning the collapse of WTC 7, including:

a) Fall time
b) Symmetry of collapse
c) Practically instantaneous collective column failure during collapse initiation, an extremely rapid lateral failure progression wave.
d) A small, compact, organized hill of rubble remaining after the fall of WTC 7.
e) The uncanny resemblance of the collapse to a controlled demolition.
f) Accidental hastily-released eulogy by the BBC of the collapse of WTC 7.
...

Cool, Bazant did not do WTC7, you failed 6 ways.
a) Fall time was so darn slow for WTC7 it is pathetic. It took over 15 seconds to collapse; can't 911 truth count.

b) it was not symetrical! Sorry.

c) took over 15 seconds to fall; last time I checked instant was zero time, so to you 15 seconds is practically instantaneous.

d) A small hill of rubble which was exactly what WTC7 was made up of; all of WTC in one small hill the exact size a pile of all the parts of WTC7 would be!!! This is a stundie if it were not so stupid. LOL, this is pure comedy! You are an engineer? Right? Or are you trying to be a comedy writer for the SOUP?

e) CD looks like a gravity collapse because gravity is the main source of energy for CD; you failed, a gravity collapse looks like WTC7, and a CD may look like WTC7 gravity collapse. It is a fact; when will you join reality; did you know gravity was the main energy source to destroy building even in CD?

f) The BBC is going to be talking point in your scientific rebuttal of Bazant who did not do WTC7? And the BBC report was wrong and you are using that as some why to back in CD for your failed paper? LOL, you are serious? ?

...
the issues most important to the CD question. ...

CD question? You have no evidence so the CD issue is a delusion held by a few who lack knowledge and can't comprehend they have no evidence.

 

[Seymour Butz]

If the floor-to-column connections were the weakest link, a column-to-column impact is not necessarily the mechanism that most favours collapse arrest.

So what is?

You've stated this twice without any embellishment.

Please. Embellish now.

 

[Seymour Butz]

Yet a follower of Bazant sees nothing wrong with the apparent contradiction. Instead, they will insult me for not seeing the "perfection" within the papers.

Maybe it's because to date, I don't see any support for your incredulity, other than your incredulity.

Funny how that is, eh?

Is there anyone insulting me who can admit that there are some errors in these papers?

He himself admitted that he was in error when he made the assumption that "hot steel" was the cause of collapse initiation.

So he then submitted evidence of another academic paper that says that creep to failure is very possible if the steel only gets to 250C, and other load conditions are met. This jives with NIST's findings.

It would be fairly easy to examine. No counting pixels would be needed.

Just do the engineering/FEA/ANSYS/load transfer/etc analysis that NIST did, and see if those load conditions make sense.

Counting pixels is a chimp's job, and will never get a new investigation, nor will it ever lead you to any kind of truth, due to the inherent errors involved.

Get with the program, yo.

 

[Major_Tom]

ElMondoHummus writes: "Mother of God... how many times do you need to be told that Bazant's group never intended to even address 7 World Trade?"

I know it wasn't intended for WTC 7. Of all the strange things that happened on 9-11-01, the way in which WTC 7 fell is probably the strangest.

How can Bazant claim:

"Previous analysis of progressive collapse showed that gravity alone suffices to explain
the overall collapse of the World Trade Center (WTC) towers. However, it remains to be checked whether the recent allegations of controlled demolition have any scientific merit. The present analysis proves that they do not."

if he doesn't address what are probably the most important questions? For important questions regarding CD on 9-11-01, the way in which WTC 7 fell is probably at the top of the list.



Bazant can address whichever points he wants. He cannot claim to prove allegations of CD have no scientific merit without addressing the most important points.

.....................................

What allegations does Bazant address in BLGB?

From the review:

"By mischaracterizing the most central arguments for demolition as

1) The belief in WTC1 freefall
2) The belief that concrete floor slabs would require (150) tons of TNT to pulverize
3) The belief that the towers should have "toppled like trees"
4) The belief in “pools of molten metal”
5) The belief that buildings can bounce
6) The belief in a "”fracture wave”, causing the collapse to occur at the rate of free fall"

Dr Bazant can paint all those who see extreme contradictions between the official version of events and witnessed events as believing absurd claims. The most central arguments for demolition are far more rational, such as:



1) The collapse initiation mechanism of WTC 1 and 2

2) Anything concerning the collapse of WTC 7, including:

a) Fall time
b) Symmetry of collapse
c) Practically instantaneous collective column failure during collapse initiation, an extremely rapid lateral failure progression wave.
d) A small, compact, organized hill of rubble remaining after the fall of WTC 7.
e) The uncanny resemblance of the collapse to a controlled demolition.
f) Accidental hastily-released eulogy by the BBC of the collapse of WTC 7.

among other features.

We can see that Dr Bazant does not directly address these issues at all.

Concerning the key differentiator between CD and natural collapse, early deformation and collapse initiation, BLGB offers little of use."

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

ElMondoHummus writes: "On top of that, pointing out how you conspiracy peddler's misunderstand Bazant is a distinct and different thing from proclaiming all his work free of error. I'm not competent enough to evaluate his math, but I sure as heck know that 1. He and his colleagues only ever intended to address the main towers themselves, and 2. As opposed to the glaring mistake made by another one of you folks above, he did indeed reference the design of the towers in his work. Those two are issues you and others don't seem to grasp."

I don't disagree with either point. He cannot claim to show allegations of CD have no scientific merit by limiting his arguments collapse progression features of WTC1 and 2.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

 

[BigAl]

I know it wasn't intended for WTC 7. Of all the strange things that happened on 9-11-01, the way in which WTC 7 fell is probably the strangest.

Repeating that doesn't make it true.

 

[Major_Tom]

Some of the CD allegations addressed by Bazant in BLGB:

1) The belief in WTC1 freefall
2) The belief that concrete floor slabs would require (150) tons of TNT to pulverize
3) The belief that the towers should have "toppled like trees"
4) The belief in “pools of molten metal”
5) The belief that buildings can bounce
6) The belief in a "”fracture wave”, causing the collapse to occur at the rate of free fall"


To me, these arguments are basically fake. Most of the "debate" we have seen involve both truthers and debunkers using many fake arguments.

One point none of us seem to disagree on is that the initial buckling sequence is a key place to look to distinguish between a natural collapse and a CD.

We all agree early deformation and the initial buckling sequence should be one of the most important places to focus. That is why I keep listing the most important features to study as:

1) The collapse initiation mechanism of WTC 1 and 2

2) Anything concerning the collapse of WTC 7, including:

a) Fall time
b) Symmetry of collapse
c) Practically instantaneous collective column failure during collapse initiation, an extremely rapid lateral failure progression wave.
d) A small, compact, organized hill of rubble remaining after the fall of WTC 7.
e) The uncanny resemblance of the collapse to a controlled demolition.
f) Accidental hastily-released eulogy by the BBC of the collapse of WTC 7.


This is not a controversial list since we already agree on the first point and the fall of WTC7 is the strangest event of all.
.............................

There are many examples of fake arguments among both truthers and debunkers. If people cannot recognize fake arguments and fake debates, they will continue to repeat them while overlooking the most important points.

It is easy for Bazant to debunk fake arguments like:

1) The belief in WTC1 freefall
2) The belief that concrete floor slabs would require (150) tons of TNT to pulverize
3) The belief that the towers should have "toppled like trees"
4) The belief in “pools of molten metal”
5) The belief that buildings can bounce
6) The belief in a "”fracture wave”, causing the collapse to occur at the rate of free fall"

He can't "prove" allegations of CD have no merit by debunking some fake arguments. He needs to recognize and address what we all know are the most important issues if he wishes to give such "proof".
>>>>>>>>>>>>>>

 

[Reactor drone]

Some of the CD allegations addressed by Bazant in BLGB:

1) The belief in WTC1 freefall
2) The belief that concrete floor slabs would require (150) tons of TNT to pulverize
3) The belief that the towers should have "toppled like trees"
4) The belief in “pools of molten metal”
5) The belief that buildings can bounce
6) The belief in a "”fracture wave”, causing the collapse to occur at the rate of free fall"


To me, these arguments are basically fake. Most of the "debate" we have seen involve both truthers and debunkers using many fake arguments.

Bazant adressed the CD features/telltales that had been brought up by the truthers at the time. You can't expect him to anticipate every iteration of CD hypothesis ever to be dreamt up by every truther for all time. If you have a hypothesis please make it. If it has already been refuted by Bazant , NIST or any other study I'm sure people will make you aware of it. As it is, you've basically made a description of the collapse proression, suggested that the initiation should be looked at more closely and thrown in a vague "what if" CD as an afterthought.

If, as you seem to believe, ther was a controlled demolition you've suggested nothing to support that position.

 

[Dave Rogers]

If the floor-to-column connections were the weakest link, a column-to-column impact is not necessarily the mechanism that most favours collapse arrest.

The point is that the column-to-column connections were the strongest link, in which case a column-to-column impact is necessarily the mechanism that most favours collapse arrest.

Dave

 

[BigAl]

f) Accidental hastily-released eulogy by the BBC of the collapse of WTC 7.

This is not a controversial list since we already agree on the first poin

Who is ""we"? You are pretty much alone on this.

On 9/11 in NYC by 4PM anyone that was paying attention to the news knew that WTC7 was doomed to collapse. It was on all the TV news.

I was one of those people. I know this first hand.

Repeating fiction doesn't make it fact.

 

[Sam.I.Am]

The BBC wasn't the only one quick on the gun saying that WTC 7 collapsed. Dan Rather said it had collapsed or was going to collapse about an hour before it did and Tom Brokow said it had collapsed before the BBC did.

Fog of war and all that...

 

[Dave Rogers]

2) Anything concerning the collapse of WTC 7, including:

a) Fall time
b) Symmetry of collapse
c) Practically instantaneous collective column failure during collapse initiation, an extremely rapid lateral failure progression wave.
d) A small, compact, organized hill of rubble remaining after the fall of WTC 7.
e) The uncanny resemblance of the collapse to a controlled demolition.
f) Accidental hastily-released eulogy by the BBC of the collapse of WTC 7.

(a) Well within experimental error of reasonable predictions, and not an issue for collapse initiation in any case.
(b) Collapse was asymmetric, the building rotating visibly northwards as it fell.
(c) Well-documented failure of columns 79-81 approx. 5±1 seconds prior to failure of perimeter columns, an unusual definition of "instantaneous"; the rapid lateral failure progression of the perimeter is an expected result, surely?
(d) Consistent with low-level collapse initiation; this is coincidentally similar to conventional explosive demolition, but is a feature of the position, not the mechanism, of collapse initiation.
(e) To the extent that this resemblance even exists, see (d).
(f) Known case of confusion in communications; a report that WTC7 was expected to collapse became, due to uncertainty, a report that WTC7 was expected to collapse or may have already collapsed, and this was erroneously simplified to a report that WTC7 had already collapsed.

All these seem perfectly reasonable explanations to anyone who isn't straining to justify a conspiracy theory.

Dave

 

[carlitos]

argument from incredulity noted

I know it wasn't intended for WTC 7. Of all the strange things that happened on 9-11-01, the way in which WTC 7 fell is probably the strangest.
...
For important questions regarding CD on 9-11-01, the way in which WTC 7 fell is probably at the top of the list.

This is not an argument or hypothesis. Please present one shred of evidence and stop proving your ignorance of this topic.