• Quick note - the problem with Youtube videos not embedding on the forum appears to have been fixed, thanks to ZiprHead. If you do still see problems let me know.

Bazant in a nutshell

^Instead of asking ridiculous things, how's about you answer DGM's questions?

DGM said:
OK, we'll skip the nuts and bolts. Can you at least explain how you came to believe the bold to be fact?

My study of physics goes back to high-school. I can't spot the problem but I feel I have a decent grasp. I'm not asking to argue, just explain the points of law that were violated, with a brief explanation of how, to the best of your understanding.
Click to expand...
 
ergo said:
Oh, they did pancake? ;) I see.

So, if FEMA already identified the correct collapse progression mechanism (and Bazant's was shown to be not only wrong but irrelevant) why did NIST bother with a further investigation?
Click to expand...
Bazant's limiting-case approach made him right from the start, because the buildings had already collapsed. He just showed that no matter how the failures were produced, the collapse was unstoppable, because even in the most favorable case for it not to happen it would happen. Even if his assumptions were wrong and it turned out that in the case of column-to-column impact the collapse could have been arrested, the way it happened made it unstoppable because of the weakness of the floor connections that I've mentioned in a previous post.

NIST's investigation wasn't concerned about collapse progression. It has been discussed to boredom and is off-topic in this thread. NIST's investigation and Bazant's first articles don't intersect significantly.
 
pgimeno said:
Bazant's limiting-case approach made him right from the start, because the buildings had already collapsed. He just showed that no matter how the failures were produced, the collapse was unstoppable.
Click to expand...

No, this is incorrect. Bazant posits a very particular failure progression. Did you not read "What Did and Did Not Cause Collapse..."? :)

Bazant's explanation does not describe pancaking whatsoever. If it did, he would not need his "crush-down, crush-up" model. Bazant's and FEMA's models are fundamentally at odds.

For NIST not to be concerned with collapse progression is negligent at best. What has yet to be explained is the disappearance of hundreds of thousands of tons of office furnishings and other common building elements (as we know, Bazant discusses concrete only) as well as identifiable human remains.
 
Last edited:
ergo said:
No, this is incorrect. Bazant posits a very particular failure progression. Did you not read "What Did and Did Not Cause Collapse..."? :)

Bazant's explanation does not describe pancaking whatsoever. If it did, he would not need his "crush-down, crush-up" model. Bazant's and FEMA's models are fundamentally at odds.

For NIST not to be concerned with collapse progression is negligent at best. What has yet to be explained is the disappearance of hundreds of thousands of tons of office furnishings and other common building elements, as well as identifiable human remains.
Click to expand...

How about you answer DGM's questions?

What is it you do, anyway, ergo? You've been asked for days, and others have told you what they do when you asked. You don't want to be known as a one-way, do you?
 
That's off topic, LSSBB. Plus, I'm not the one making claims that models don't have to represent any workable version of reality.
 
ergo said:
That's off topic, LSSBB. Plus, I'm not the one making claims that models don't have to represent any workable version of reality.
Click to expand...
I already gave you examples from business, science and engineering where models don't have to exactly match reality. That you don't understand that models don't need to closely approximate reality appears to point to you not having any experience in any of those areas. In addition, the burden of proof is not on us anyway. Don't shift it. As far as I can tell, you just don't want to answer the question - you want to be able to get answers and won't give any yourself. That's kinda selfish, don't you think?
 
ergo said:
pgimeno said:
Bazant's limiting-case approach made him right from the start, because the buildings had already collapsed. He just showed that no matter how the failures were produced, the collapse was unstoppable.
Click to expand...
No, this is incorrect. Bazant posits a very particular failure progression. Did you not read "What Did and Did Not Cause Collapse..."? :)
Click to expand...
That's a different unrelated paper. Are we discussing the first two papers (404 and 405, published in SIAM News and JEM respectively)? I was referring to them exclusively, and within that context my assertion was correct. Bazant did other models later which were not intended as limiting cases but they were not being discussed here. Stop gish-galloping.

And why have you added a period to my last sentence above if it didn't end there? That's distorting my quotation.


ergo said:
For NIST not to be concerned with collapse progression is negligent at best. What has yet to be explained is the disappearance of hundreds of thousands of tons of office furnishings and other common building elements (as we know, Bazant discusses concrete only) as well as identifiable human remains.
Click to expand...
That has been explained/refuted where it is on topic. Here it isn't. It's cynical of you to complain about off topics.
 
Proof ergo does not understand physics, Bazant's work, models and 911.

ergo said:
It's OK. I'm just now realizing why bedunkers think Bazant's is a model of reality. :)

To argue further on this path would get into discussions that have occurred countless times here and elsewhere. It also gets complicated for this discussion because not only does his model not represent what happened, but it's also not workable in any reality based on Newtonian physics, ... ?
Click to expand...

You don't understand physics because Bazant work is based on math and physics. Which you make up lies like this because you don't understand what physics is. Your moon size debris field of physics is nonsense.

Your statement is bedunking yourself. You might be the only bedunker at JREF; someone who debunks their own work. You better stop posting in a thread where knowledge of physics and math is needed.

Please show with physics where Bazant breaks the laws of physics? Why can't you do this? You make a claim and can't support it. Why? Because this is physics for you http://www.internationalskeptics.com/forums/showpost.php?p=6263596&postcount=621 . Bedunker is baby talk? That is so cute.
 
Last edited:
LSSBB said:
I already gave you examples from business, science and engineering where models don't have to exactly match reality. That you don't understand that models don't need to closely approximate reality appears to point to you not having any experience in any of those areas. In addition, the burden of proof is not on us anyway. Don't shift it. As far as I can tell, you just don't want to answer the question - you want to be able to get answers and won't give any yourself. That's kinda selfish, don't you think?
Click to expand...

Way back when, I learned Crystal Field Theory as a chemistry student. The joke about CFT was that it was "Too Good to be True", because it was easy to work with, and gave reasonably accurate results, though its assumptions were over-simplified. OTOH, Molecular Orbital Theory was "Too True to Be Good", since its assumptions were more accurate, but the calculations were very complex. (This is no longer true due to 40+ years of advancing computer power.)
 
lexicon008 said:
Fair enough, but it still begs the question..why would you put your name and reputation on the line that early when there has been zero investigation done. You're taking a large leap of faith there.
Up to that point you have numerous media sources saying it looks like a controlled demo. You have people like New Mexico demolitions expert Van Romero saying it looked like explosives did it. You have fire fighters at the scene describing explosions. There are numerous radio calls about explosions.
So why does bazant seemingly ignore all of these reports/people and without any investigation come out with this paper?
Right or wrong it's pretty Ballsy
Click to expand...

It is a paper, a model, it is what he does. He is saying the collapse is possible due to gravity alone. End of story, it does not say 19 terrorist did it, it says a building collapse can happen. Math and physics. There is no reputation involved beyond the math/engineering/physics. You can check his work and decide if it is right, find errors, correct them, and see it is true; the building can collapse due to gravity; BTW, the same theme, using gravity to do the work is used in CD.
Bazant is an expert at it, no big deal, he could do it in hours. I am not surprised someone with his expertise was not curious if he could explain the collapse with an engineering model; no surprise he did it in a day or two; he must be an engineer, or something.

I bet Bazant cheated and saw the collapse on TV; saw the fire and impact. BTW, if you did see the impact, of 175, it looked like a 2000 pound bomb hit the WTC. And if you do the math and physics, the KE is equal to 2093 pounds of TNT. Math, physics, reality.
 
beachnut said:
It is a paper, a model, it is what he does. He is saying the collapse is possible due to gravity alone. End of story, it does not say 19 terrorist did it, it says a building collapse can happen. Math and physics. There is no reputation involved beyond the math/engineering/physics. You can check his work and decide if it is right, find errors, correct them, and see it is true; the building can collapse due to gravity; BTW, the same theme, using gravity to do the work is used in CD.
Bazant is an expert at it, no big deal, he could do it in hours. I am not surprised someone with his expertise was not curious if he could explain the collapse with an engineering model; no surprise he did it in a day or two; he must be an engineer, or something.

I bet Bazant cheated and saw the collapse on TV; saw the fire and impact. BTW, if you did see the impact, of 175, it looked like a 2000 pound bomb hit the WTC. And if you do the math and physics, the KE is equal to 2093 pounds of TNT. Math, physics, reality.
Click to expand...

Again, fair enough, the guy is an engineer and hey maybe he's really that good.
But what then was the problem of the hundreds of other engineers that worked for fema, nist or anyone else for that matter that spent months/years trying to figure this out? They were all scratching their heads.
Did bazant just decide, hmm maybe i will go look up all the variables i need to know (how did he manage to find them all anyway considering others had a hell of a time geting them), ignore the fact that this was a terrorist attack and hey maybe there were other bombs..i mean they bombed the place before right...but not this time..I'll just assume nothing but gravity is working here..and if it comes out later that the whole place was rigged..oh well my bad? Again..ballsy..lol

Gravity is used by CD, you're entirely correct..but CDs do sometimes fail. Cd's require huge amounts of prep to weaken the structure ahead of time and they still fail. CDs require almost every load bearing beam to be blown apart and they still fail. Bazant is essentially saying you could have rigged a couple floors really high up to blow and nothing else was needed to completely destroy the buildings.
Again i'm not arguing against a collapse..i just find it really hard to see a complete collapse.
Math. physics. All great stuff, but those that only work in math and physics and not in the real world find out that thier math and physics don't always work. The real world isn't the perfect world of math and physics. Sometimes someone has to steer the boat.
 
lexicon008 said:
Again, fair enough, the guy is an engineer and hey maybe he's really that good.
But what then was the problem of the hundreds of other engineers that worked for fema, nist or anyone else for that matter that spent months/years trying to figure this out? They were all scratching their heads.
Click to expand...

This confution is only because you don't understand the Bazant paper. The other engineers did, that's why they studied the collapse like they did.
Did bazant just decide, hmm maybe i will go look up all the variables i need to know (how did he manage to find them all anyway considering others had a hell of a time geting them),
Click to expand...

Again, you don't understand the paper. Different problems, different approaches.

ignore the fact that this was a terrorist attack and hey maybe there were other bombs..i mean they bombed the place before right...but not this time..I'll just assume nothing but gravity is working here..and if it comes out later that the whole place was rigged..oh well my bad? Again..ballsy..lol
Click to expand...

All with no actual evidence. Why should he ignore this?

Gravity is used by CD, you're entirely correct..but CDs do sometimes fail. Cd's require huge amounts of prep to weaken the structure ahead of time and they still fail. CDs require almost every load bearing beam to be blown apart and they still fail. Bazant is essentially saying you could have rigged a couple floors really high up to blow and nothing else was needed to completely destroy the buildings.
Click to expand...

This is why he concerned himself with energy transfer. You should actually read the paper. He actually explains his methodology. Essentially, he proved this to be true.
Again i'm not arguing against a collapse..i just find it really hard to see a complete collapse.
Math. physics. All great stuff, but those that only work in math and physics and not in the real world find out that thier math and physics don't always work. The real world isn't the perfect world of math and physics. Sometimes someone has to steer the boat.
Click to expand...

That's why you are not an engineer. You want to "see" it, not grasp the math.

Would your recommendation be a full scale experiment?
 
Last edited:
lexicon008 said:
Again, fair enough, the guy is an engineer and hey maybe he's really that good.
But what then was the problem of the hundreds of other engineers that worked for fema, nist or anyone else for that matter that spent months/years trying to figure this out? They were all scratching their heads.
Click to expand...

General vs. specific, and progression vs. initiation. Bazant's paper demonstrated that, whatever the initiation mechanism, once the top block had descended the height of a floor then nothing could stop the collapse - a very general conclusion. The purpose of the NIST investigation was to find out what the specific initiation mechanism was, in order to make recommendations for future building design. NIST didn't investigate collapse progression of the Twin Towers, for the simple reason that any information on it would be useless.

Dave
 
lexicon008 said:
Again, fair enough, the guy is an engineer and hey maybe he's really that good.
But what then was the problem of the hundreds of other engineers that worked for fema, nist or anyone else for that matter that spent months/years trying to figure this out? They were all scratching their heads.
Click to expand...
On how it exactly happened, not on whether it was possible. Bazant merely showed it was mathematically possible.


lexicon008 said:
Did bazant just decide, hmm maybe i will go look up all the variables i need to know (how did he manage to find them all anyway considering others had a hell of a time geting them), ignore the fact that this was a terrorist attack and hey maybe there were other bombs..i mean they bombed the place before right...but not this time..I'll just assume nothing but gravity is working here..and if it comes out later that the whole place was rigged..oh well my bad? Again..ballsy..lol
Click to expand...
By the time the only explanation considered by most people was a fire-induced collapse. No surprise there. Demolition conspiracy theories arose at a later time.


lexicon008 said:
Gravity is used by CD, you're entirely correct..but CDs do sometimes fail. Cd's require huge amounts of prep to weaken the structure ahead of time and they still fail. CDs require almost every load bearing beam to be blown apart and they still fail.
Click to expand...
For some buildings, yes. For some others, they can just completely collapse due to fire like this one: http://www.youtube.com/watch?v=p22OkclAU3o or even just by themselves like this one: http://www.youtube.com/watch?v=rM1-7XnbcjI

The WTC was specially prone to the kind of progressive collapse that happened because it had no columns in the main floor area, only in the core and perimeter.


lexicon008 said:
Bazant is essentially saying you could have rigged a couple floors really high up to blow and nothing else was needed to completely destroy the buildings.
Click to expand...
Correct, assuming you could make the rigging survive the plane impacts. Actually you just needed the plane impacts and fire, you know.


lexicon008 said:
Math. physics. All great stuff, but those that only work in math and physics and not in the real world find out that thier math and physics don't always work. The real world isn't the perfect world of math and physics. Sometimes someone has to steer the boat.
Click to expand...
Sometimes the unknowns are too many to model them with math and physics, but that doesn't mean they don't work in the real world. There's a difference.
 
Dave Rogers said:
General vs. specific, and progression vs. initiation. Bazant's paper demonstrated that, whatever the initiation mechanism, once the top block had descended the height of a floor then nothing could stop the collapse - a very general conclusion. The purpose of the NIST investigation was to find out what the specific initiation mechanism was, in order to make recommendations for future building design. NIST didn't investigate collapse progression of the Twin Towers, for the simple reason that any information on it would be useless.

Dave
Click to expand...

Thats a rather odd way of looking at it though isn't it? We want to know how it started to stop it from happening but if it happens we don't want to know how to stop it?
Obviously if removing the structural support of 1 upper floor could lead to a total loss don't you think you might wanna prevent the loss of one upper floor from causing a total loss?
Isn't that the whole purpose of redundancy, safety factors etc.
If they don't care why it managed to progress as it did then how do they stop that kind of thing in the future??
 
"By the time the only explanation considered by most people was a fire-induced collapse. No surprise there. Demolition conspiracy theories arose at a later time."

uh no they were suspecting it that day. Fire fighters, police, the news media and many others were talking bombs, demolition etc. Yet bazant ignored that and came out with his idea 48 hours later??

"Bazant merely showed it was mathematically possible."

One can show just about anything is mathematically possible..but that doesn't make it fact.
 
Last edited:
You must log in or register to reply here.

Back
Top Bottom