OOS Collapse Propagation Model

[JSanderO]

Ozzie,

I have always thought that the understanding of the collapses of those buildings would HAVE to involve the nature and perhaps details of the particular structures. How could it not? It's like trying to figure out the Challenger explosions and discussing the amount of fuel on board and whether it could blow up the rocket without looking at the construction and the engineering and the environment etc. The Mr B's stuff seems to conceptualize the towers as physics problems NOT buildings...not THOSE buildings. IN a few words this is not helpful.

When I mention issues such as "liability" or that the deign "participated" in its own "demise" this is not intended strictly as a legal case... though I suppose it could be. That is to say... IF the designs determined how they fell, the speed, the time they remained standing, the fact that it was total and so on one should probably evaluate the MERITS of the design... and even compare them to other approaches. We KNOW that the plane strikes are way out of spec... and maybe ANY building would be a goner. I don't know how to determine this... but it IS a fair question to ask.

And you know I raised the single column to global collapse question on this forum. If not all buildings WILL go global with a single column failure is it safe to say that the ones that DO are "inferior" designs? ... At least for some reasons.

My hunch is that SOME designs are "better" ie more survivable than others. Does that make the less survivable "flawed engineering"? Maybe and maybe not. It's a legitimate question to ask and I think it was at the core of concern for many people post 9/11. Can the building I work and or live in completely collapse in 10 seconds after a say some structural damage and uncontrolled fires burning for 1 hr. Or does it take 7hrs? Or maybe it can't completely collapse? Sure this is a life safety issue. Limit cases are not very helpful.

I think NIST made a feeble attempt to identify a mechanism to explain the collapses. I think they probably got it wrong. I have mentioned some of the reason I suspect they did. I can't ascribe malfeasance to anyone. I tend to think it more "incompetence" or some sort of "institutional" culture which prevents people from thinking rationally.

A case in point...

What would happen to most tall buildings struck by a large plane with almost no fuel on a very high floor? Would it collapse on impact? Would it stand but severely damage for X minutes, or hours or maybe not collapse? Can we understand the building performance and isn't it related to the engineering design?

I suspect... "surviving" the impact is not as much of an engineering feat as many seem to think it was. It's remarkable perhaps on the face... but when one looks at the NATURE of tall frames of high rises... it seems like most would be severely damaged and no collapse from the IMPACT.

And so we are told it is FIRE that ultimately destroyed the twins and essentially was the culprit for 1WTC. Fire was in different places (elevation) and led to global collapse. But it is claimed (by NIST) to have worked on DIFFERENT nodes/parts of the STRUCTURE... one was a girder walk off column buckling and the other has some sort of floor truss failure AND not a girder walk off. Seems to me this is about STRUCTURE and engineering DESIGN. Fires are not smart enough to know where to go to destroy a building.

++++

At least ROOSD looks AT THE STRUCTURE as a means to explain the global collapse we saw. Evening Greening with his latest aluminum explosion fantasy ignores the structure assuming huge explosions locally. The NIST 7wtc explanation is really a very specific "CD -like" single column take out to completely destroy a building. Sounds like demolition companies need to study that one to save a lot of money rigging entire arrays of columns on multiple floors for their projects.

++++

Admittedly this has been some discussion that mass can only drop when the normal axial load paths are not working as designed. I suspect Mr B et all did not see that one., though they completely understand it I suppose. So the real question is how do you get all that mass... threshold and over the entire footprint in the twins to lose axial coupling? And how why did not the 7WTC single column failure not be a collapse of just the NE corner?

Do you think those questions have been answered?

 

[JSanderO]

i think you do. You stated it perfectly in that last set of comments I quoted.




Not that. I care about the living, not those already mentally dead, trapped in their fixed memes.

I do not post here to 'chat' or for the mental stimulation. I document the crazy and try to provide a resource for those who are looking for more than a cartoon history of the collapse events. The collapse events are in the past, but the stupidity and false representations are very much in the present. There is a way to 'disabuse' oneself and others of the mess that various perceived authority figures are leaving in their wake. It is an incredible learning opportunity, to see how powerful empty memes can be. To see how history is actually written.

There are many people down wind from this insanity. They deserve better than what they were given. This topic is very much of the future, not just the past.

I suspect a lot of what we "know" about history is not accurate. Perhaps significant details are missing or maybe some facts are all wrong. The entire "discovery" of North America seems more myth than fact. It's not as if there were no indigenous people living in the "Americas" before the "explorers" discovered the "new world". At the time of its "discovery" what is now called Mexico city was the largest city bin the world... or so I read somewhere. Even if was the 10th largest... this sort of tell changes what the "history" we are taught in school... and we STILL celebrate "Columbus Day" in the USA.

I suppose the take away is that this sort of "revisionism" serves someone(s)' interests.

 

[Crazy Chainsaw]

It's not - it is physics looking gobbledegook from a person who does not know what he is describing.

No it is a person describing the physics as he understands them given the three sets of energies used in a hypothetical model. The physics work as long as no other force energy is introduced.

I reject your assertion that Benson's material falsifies the real event.

How could the physics of a model falsify reality?
Didn't know math on a computer with a given set of forces could do that.

False analogy. The error is not in language. It is that one talks of the real event whilst the other is describing a fantasy. I also reject your assertion that fantasy overrules reality.
Neither of those assertions should require any proof but...if anyone insists...

One talks about the real observed event, M T, one talks about how the building should have behaved, in a mathematical model given the forces used in the model, as based on a correct understanding of the laws of physics. DBB.

All I am saying is if we forget the pety squabbles over real event, and model, and compare
The two, it might give us some interesting incite, to what actually happened.
How ever truther and debunker are fun and addictive games to play, and this is a site dedicated to those games.

 

[JSanderO]

N
All I am saying is if we forget the pety squabbles over real event, and model, and compare
The two, it might give us some interesting incite, to what actually happened.
How ever truther and debunker are fun and addictive games to play, and this is a site dedicated to those games.

Engineering is applied physics... A36 steel us different from A54 steel, same for bolts and welds and concrete and so on. Physics and people like DBB and Mr B do NOT deal with the APPLIED physics and treat the collapse like a model and this I must say is not reality based. Theory is fine... I am interested in understanding what ACTUALLY happened to those buildings.

 

[Crazy Chainsaw]

Engineering is applied physics... A36 steel us different from A54 steel, same for bolts and welds and concrete and so on. Physics and people like DBB and Mr B do deal with the APPLIED physics and treat the collapse like a model and this I must say is not reality based. Theory is fine... I am interested in understanding what ACTUALLY happened to those buildings.

Structure can only tell you so much, then it boils down to forces and reactions, the physics and chemistry.
and yes I understand the chemistry of ferite crystal bonding with carbon and other element's to form Alloys as I have pointed out numerous times here.

I also understand the chemistry of Aluminum, aluminum oxide crystals and the strong bonds they produce, almost as strong as carbon in diamond.

 

[JSanderO]

Structure can only tell you so much, then it boils down to forces and reactions, the physics and chemistry.
and yes I understand the chemistry of ferite crystal bonding with carbon and other element's to form Alloys as I have pointed out numerous times here.

I also understand the chemistry of Aluminum, aluminum oxide crystals and the strong bonds they produce, almost as strong as carbon in diamond.

I left off the NOT....

The point being that metals... steel can be of the same density but have vastly different properties and so to deal ONLY with MASS is not necessarily leading one to understanding in a structural failure.

 

[Major_Tom]

False analogy. The error is not in language. It is that one talks of the real event whilst the other is describing a fantasy. I also reject your assertion that fantasy overrules reality.

That is correct. But I don't think you realize how strongly these people actually believe what they are saying.


Once again, Crazy Chainsaw is only replicating a meme started and supported by others since the first page of the thread.

Here are the collected early posts once again of those who are most responsible for establishing this meme at the beginning of the thread:


Newtons Bit comments
R Mackey comments
Dave Rogers and Myriad comments


Newtons Bit has an MS in Structural Engineering.
R Mackey identifies himself as a 'rocket scientist' who works (or worked) for NASA.
Dave Rogers has a PhD in Physics.
Myriad is (or was) a moderator in this forum.


David Benson has a PhD in Mathematics.

Bazant has a PhD in Structural Engineering.


Therefore, you are not looking at just a few exceptions. You are observing the behavior and mentation of representatives of an entire subculture.


I am not joking when I point out that they actually believe what they are saying and they appear ready to defend those beliefs indefinitely and passionately, attacking anyone who stands in their way.


Such is the power of the replication of memes which are fundamentally empty of content or accuracy within the written WTC collapse histories accessible to the public.

 

[GlennB]

Here are the collected early posts once again of those who are most responsible for establishing this meme at the beginning of the thread:

Newtons Bit comments
R Mackey comments
Dave Rogers and Myriad comments

Dipping at random into the R Mackey comments there I find the entirely unremarkable:

Personally, I like how he seems to think Bazant and Le (2002) is supposed to be an accurate description of the collapse rather than a limiting case, or that he thinks that plus Bazant and Verdure (2006) cover the entire scope of the literature. As if we hadn't explained this to practically every Truther who ever lived a million times each.

Ah well. I guess it keeps them occupied, at least.

 

[beachnut]

...
Such is the power of the replication of memes which are fundamentally empty of content or accuracy within the written WTC collapse histories accessible to the public.

Yes, you don't like models and science. Written history - Global collapse ensued. The short version, which is understood by most engineers.
What is the purpose of a collapse history?

You never did answer when you dropped the fantasy CD meme. When, how, and why did you drop the CD stuff?

 

[Crazy Chainsaw]

That is correct.
Once again, Crazy Chainsaw is only replicating a meme started and supported by others since the first page of the thread.

BS. Major Tom, physics and mathematics can not be a meme!

Benson knew of the ROOSD like event but even ROOSD and accounting for the specific structure and steel in the towers it would given the math in the models would have formed a Homogeneous front of debris.
In fact partial Homogeneous fronts are the driving force of the floor over loading
The question is what produced the added fluid dynamics, and mass shedding that would have prevented a larger shielding mass preventing observable crush up in the early
Collapse?

PS, Major Tom I find it highly Hypocritical, that you are doing to me now, what you claim others have constantly done to you!

 

[JSanderO]

BS.
In fact partial Homogeneous fronts are the driving force of the floor over loading
The question is what produced the added fluid dynamics, and mass shedding that would have prevented a larger shielding mass preventing observable crush up in the early
Collapse?(

What IS the mass shed? How do you know how much mass was "shed"? Are you referring to the ejecta seen shooting out the windows during collapse?

Why do you think this is a significant amount (or not) to alter the collapse?

 

[WilliamSeger]

What IS the mass shed? How do you know how much mass was "shed"? Are you referring to the ejecta seen shooting out the windows during collapse?

Any debris that went over the side couldn't have contributed to the destruction of the structure below. That would include the perimeter columns and the debris that pushed them outward immediately after shearing the truss connections. M_T's conjecture that the perimeter wall had a "funnel" effect is not supported by observation or logic.

 

[Dave Rogers]

Dipping at random into the R Mackey comments there I find the entirely unremarkable:

Personally, I like how he seems to think Bazant and Le (2002) is supposed to be an accurate description of the collapse rather than a limiting case, or that he thinks that plus Bazant and Verdure (2006) cover the entire scope of the literature. As if we hadn't explained this to practically every Truther who ever lived a million times each.

Ah well. I guess it keeps them occupied, at least.

Dipping into these links, which I only saw in quoted form, I see that MT has quoted me extensively, quoted some questions he asked me (which, presumably, I never bothered to read), and then quoted later posts of mine to give the impression that they are answers to his questions. A very subtle form of dishonesty, this, that carefully stops short of actually lying. I vaguely wonder why he feels he needs to do that (though not enough to bother reading his explanations, which I probably wouldn't believe).

Dave

 

[WilliamSeger]

Dipping into these links, which I only saw in quoted form, I see that MT has quoted me extensively, quoted some questions he asked me (which, presumably, I never bothered to read), and then quoted later posts of mine to give the impression that they are answers to his questions. A very subtle form of dishonesty, this, that carefully stops short of actually lying. I vaguely wonder why he feels he needs to do that (though not enough to bother reading his explanations, which I probably wouldn't believe).

Dave

I haven't read most of it, but from what I have read, most of the supposed "model" vs. "real" confusion seems to be just M_T's preferred strawman.

 

[JSanderO]

Any debris that went over the side couldn't have contributed to the destruction of the structure below. That would include the perimeter columns and the debris that pushed them outward immediately after shearing the truss connections. M_T's conjecture that the perimeter wall had a "funnel" effect is not supported by observation or logic.

The facade peeled away and was probably from Euler buckling with some "push" from air pressure and some from the lateral pressure of the "collapse" fluid... like the lateral pressure that required tension rings on water tanks and silos.

You don't expect a net rectangular / cubic pile of dust... n'est pas... more a cone or pyramid form.

 

[GlennB]

You don't expect a net rectangular / cubic pile of dust... n'est pas... more a cone or pyramid form.

It's n'est-ce pas

And there wasn't comminution to the point of total reduction to dust/sand/aggregate (the constituents of the concrete), so I have no idea what you're saying on that subject any more.

 

[Major_Tom]

Dipping at random into the R Mackey comments there I find the entirely unremarkable:

Personally, I like how he seems to think Bazant and Le (2002) is supposed to be an accurate description of the collapse rather than a limiting case, or that he thinks that plus Bazant and Verdure (2006) cover the entire scope of the literature. As if we hadn't explained this to practically every Truther who ever lived a million times each.

Ah well. I guess it keeps them occupied, at least.

But if you understood what you were reading, or R Mackey understood what he was writing, you'd know that Bazant and Le was written in 2008 and is actually the closure of Bazant and Verdure (2007).

He was writing about an entirely different paper with an entirely different argument and didn't know it.

If you were clueless of the subject matter his comment would seem reasonable, as you have just demonstrated.


>>>>>>>


But your reading and the writing of R Mackey demonstrate a crucial point in how these memes are generated and replicated. The casualness with which R Mackey makes such a bone-headed statement combined with the casualness you demonstrated when reading and agreeing with it is what allows this ......stupidity..... to thrive within the JREF/ISF environment.

The participating posters were never in a position to discuss these subjects in a competent way, but they were so incompetent in their responses that they don't even notice how poorly they perceive this information. It is this extreme casualness with fact-checking combined with an utter lack of awareness that allowed such shallow views to be replicated over and over for so many years.

People here tend to be overly confident in their own ignorance, and they don't even notice it happening.

 

[DGM]

But if you understood what you were reading, or R Mackey understood what he was writing, you'd know that Bazant and Le was written in 2008 and is actually the closure of Bazant and Verdure (2007).

He was writing about an entirely different paper with an entirely different argument and didn't know it.

If you were clueless of the subject matter his comment would seem reasonable, as you have just demonstrated.

I'm curious as to why you are still harping on these things? Everyone else has moved on.

Do you actually have a point to make?

 

[GlennB]

But if you understood what you were reading, or R Mackey understood what he was writing, you'd know that Bazant and Le was written in 2008 and is actually the closure of Bazant and Verdure (2007).

He was writing about an entirely different paper with an entirely different argument and didn't know it.

If you were clueless of the subject matter his comment would seem reasonable, as you have just demonstrated.

Something that he acknowledged a few posts later - a slip, and nothing to do with the substance of the discussion. He was writing about B+Z, as you well know from the exchange at the time, as did he.

 

[DGM]

Something that he acknowledged a few posts later - a slip, and nothing to do with the substance of the discussion. He was writing about B+Z, as you well know from the exchange at the time, as did he.

Did he score a point?