Merged Applicability of Bazant's model to the real world

[ozeco41]

Here is an example of Newton's Bit conjuring up a surviving upper block and the magic zone B in his description of how real buildings would collapse.....

Well I have no desire to get into the middle of a sandwich which is a heated personal conflict and clearly polarised "debunker side v presumed truther". Not the least for the reasons I have previously outlined about my reservations as to how far Bazant can be taken, including how Bazant's bits of ongoing thinking in various papers fit together if they do.

However....

In addition, sticking firmly to my policy of "think before applying models blindly", I need to progress my own thinking about the details of WTC Twin Towers collapses. And I will continue to limit myself to WTC Twin Towers. I will also continue my practice of working from what actually happened back towards the Bazant models i.e. the reverse of what seems to be the common practice of assume a model and see if it fits (or presume that it does???).

So I will post some more ideas about WTC but at this stage make preliminary comments on your two posts.

From post #139

...From page 2 of the OOS model thread I asked him:

"1) In BL, can you explain why Dr Bazant insists that crush down must be complete before crush up occurs. Does he mean this literally?

2) Do you consider the equations of motion in BV, equations 12 and 17, to be accurate considering the information in the ROOSD study?"

He answered: " ffs Read the paper. Here, let me explain it to you:

The upper block is accelerating at near g. This means that there is very little force being applied to it. We can imply that the absolute maximum height of destruction occurring through the upper block will happen at a rate equal to (g - a). However the upper block has some residual strength. This force is much less than the original capacity upper block which is somewhere in the neighborhood of 3*m*g.

There will be, during the initial stages of the collapse that forms the rubble layer, destruction on both the upper block and lower block. But once it gets moving? Not so much.

You've provided no information on how this is incorrect."

Well that does not answer your questions AND throws the burden of proof back to you. It seems clear that you are receiving the short shrift that is afforded to those categorised as truthers. I will not address the merits of either the topic OR the apparent categorisation of yourself.

Then this seems to be the core issue of your following paragraphs:

...They all have a good level of education but they all made the same mistake. Just a coincidence? Where did all three posters get the idea that crush down, then crush up and upper block survival can be applied to real buildings?...

Then from your second post - Post # - the central issue seems to be this:

...You cannot just mix all 4 Bazant papers together like you are making mashed potatoes. BZ gives one argument while BV, BL and BLGB develop equations of motion to describe real movement of real buildings, and we can see the equations applied to the WTC towers in BLGB.

You cannot quote about the assumptions most favorable for survival from the 2002 paper to refute my arguments against collapse progression model from a different paper describing a different model from a 2007 paper.

In the quote can you see how he mixes the two models without realizing it?

So I see those as the key points and I will give some thought into territory which I have not bothered with previously.

The central question from my perspective is "where in the global collapse of each of the twin towers did the top block fall apart"? Previously to this recent discussion I have accepted that the top block started off as an integral whole, fell apart somewhere in the global collapse and was not an integral hole at the bottom. It mattered not to me where it happened because integral whole or component parts it was the total falling mass which caused the pancaking OOS collapse.

I have never regarded Bazant's "crush up only happened at the bottom" as a viable explanation so leave it with me for a few hours.

 

[pgimeno]

You cannot quote about the assumptions most favorable for survival from the 2002 paper to refute my arguments against collapse progression model from a different paper describing a different model from a 2007 paper.

What arguments? You have shown no arguments against Bazant's collapse progression model, other that it does not correspond exactly with reality, something that Bazant knew as I have proved in the OP, and which is irrelevant to his arguments.

 

[Tony Szamboti]

Bazant got 31 times overload. Just for interest when I first answered the question back in early 2008 I guestimated it was in the order of 20 times to 50 times overload. Without the complicated maths.


Now recall my suggestion to "remember point A". The "jolt" which Bazant's conservative model predicted as the top block struck at "point A"? That is the "Missing Jolt" which Tony Szamboti went looking for in his paper of that name. He took Bazant's worst case as gospel. But the WTC Twin Towers did not start to collapse by the worst case of Bazant's model. Hence the futility of Tony's search for a jolt which wasn't needed. It wasn't there because it wasn't needed.

The overloads you guesstimated could not happen without a jolt and your use of it here shows you want it both ways. You want an overload without a jolt. Sorry, but you can't have that in this world.

If you decide to back off the need for a jolt as you contradictorily state in the second paragraph I am quoting from you, then you need to explain why every Verinage demolition shows a significant and measurable deceleration (jolt). If WTC 1 were somehow able to naturally collapse without a jolt it would be a severe exception to the rule.

 

[femr2]

you need to explain why every Verinage demolition shows a significant and measurable deceleration (jolt).

I don't think this is the right thread for jolt discussion, and if you respond Tony, please make it a once only with a redirect to one of your other jolt threads.


Verinage demolitions show *jolts* because we can *see* the behaviour. There is no perimeter.

As far as I'm concerned, there ARE jolts during the WTC descents, but they are between elements which are either disconnected from the core and perimeter (floors), or (as they are nothing like axial core column impacts) of much less magnitude and not transmitted to regions such as the NW corner due to a) non-rigid structure and b) short *jolt* duration and c) lots-n-lots of jolts spread out over time and...

If WTC 1 were somehow able to naturally collapse without a jolt it would be a severe exception to the rule.

Regardless of natural or not, WTC 1 mode of descent is quite different to verinage. I don't think they should be compared. Verinage is applied to very different structures.

 

[femr2]

Well I have no desire to get into the middle of a sandwich which is a heated personal conflict and clearly polarised "debunker side v presumed truther".

A wise decision.

In my opinion, that this thread exists allows an underlining of previous mistakes.

It has been made clear that there are quite strict limitations on applicability of Bazant's model.

Poring over prior incorrect usage is unlikely to result in all of those responsible for crossing the line turning around and making amends.

I suggest that from this point on (6/9/10) there is no excuse, and I expect that any instances of folk applying the model incorrectly will end up being posted here and dissected. That's a good thing, and a useful end result, imo.

 

[beachnut]

A wise decision.

In my opinion, that this thread exists allows an underlining of previous mistakes.

It has been made clear that there are quite strict limitations on applicability of Bazant's model.

Poring over prior incorrect usage is unlikely to result in all of those responsible for crossing the line turning around and making amends.

I suggest that from this point on (6/9/10) there is no excuse, and I expect that any instances of folk applying the model incorrectly will end up being posted here and dissected. That's a good thing, and a useful end result, imo.

911 truth has no clue what models are for, they have failed CD delusion as they waste time commenting on work they can't comprehend, let alone use to cure their failed delusions.

 

[pgimeno]

It has been made clear that there are quite strict limitations on applicability of Bazant's model.

I don't agree on that. There are limitations, but these limitations are not well known. Therefore, it can't be claimed that there are quite strict limitations. There are limitations, but we don't know the limitations of the limitations, so to say.

(Does that count as a second order derivative? Will it be infinitely derivable? Do we get a squared error in the measurement? )

I was serious on the first paragraph, though. "Quite strict limitations" is a bit of a stretch. In case of doubt, a comparison with the real world can be helpful in determining the applicability.

 

[femr2]

I don't agree on that. There are limitations, but these limitations are not well known. Therefore, it can't be claimed that there are quite strict limitations. There are limitations, but we don't know the limitations of the limitations, so to say.

What I'm saying is that if someone appears to be misapplying the model, it's likely going to be brought in here and given a shake-down.

Hopefully no-one will from now on

 

[ozeco41]

The overloads you guesstimated could not happen without a jolt and your use of it here shows you want it both ways. You want an overload without a jolt. Sorry, but you can't have that in this world....

Tony this is not the thread to reopen "jolt" debate.

I am writing in the context of what Major_Tom labels OOS collapse during the global collapse phase of the twin tower destruction. Your "jolt" hypothesis relies on one of two possible situations which could apply to the "initial collapse". Those two being:

• Initial collapse occurred due to impact and accumulated fire damage alone; OR
• it resulted from that damage assisted by demolition.

Your jolt paper does not rebut the first, no demolition, option which is the setting I am writing about.

Explaining briefly - within the no demolition scenario - once the initial collapse was under way there was no significant column on column axial contact to transfer loads. There could not be because the top block was falling. So, whatever the detailed mechanisms involved, top column bits were already bypassing their bottom column counterparts.

The only significant contact in the outer floor and outer tube area was top block on floor area. That is why it was 20-50 times overload and sheared the floor connectors with minimal jolt.

So your scenario is only one of two potential scenarios. I am addressing the other scenario which you ignore and this is not the thread to reopen Jolt discussion. Full explanation is beyond the scope of this thread and I won't pursue it here.

... you need to explain why every Verinage demolition shows a significant and measurable deceleration (jolt). If WTC 1 were somehow able to naturally collapse without a jolt it would be a severe exception to the rule.

Sorry but I never accept reversal of burden of proof. Even if I did there is no analogy between verinage and the "no demolition" mechanism which occurred at WTC.

 

[ozeco41]

A wise decision.

Could be age ----- the 41 in the user name is easy to decode.

In my opinion, that this thread exists allows an underlining of previous mistakes...

...and maintaining the narrow scope of topic could assist reasoned discussion. The "noise to signal" ratio tends to get a bit high when questioning the accepted wisdom.

It has been made clear that there are quite strict limitations on applicability of Bazant's model....

...but:

• We are not clear where the lines are at this stage; AND
• Some members are content with "its only a model and models have limits" whilst others like me currently want to know "where those limits are"; AND
• Some members like me up till three days ago just avoid going near any possible limits.

...Poring over prior incorrect usage is unlikely to result in all of those responsible for crossing the line turning around and making amends...

Are you sure you meant "all" Surely you jest - maybe "any" or "few"

I suggest that from this point on (6/9/10) there is no excuse, and I expect that any instances of folk applying the model incorrectly will end up being posted here and dissected. That's a good thing, and a useful end result, imo.

...and working with real examples is usually the most productive way of defining where the lines are in the grey areas.

 

[ozeco41]

I don't agree on that. There are limitations, but these limitations are not well known. Therefore, it can't be claimed that there are quite strict limitations. There are limitations, but we don't know the limitations of the limitations, so to say.

(Does that count as a second order derivative? Will it be infinitely derivable? Do we get a squared error in the measurement? )

I was serious on the first paragraph, though. "Quite strict limitations" is a bit of a stretch. In case of doubt, a comparison with the real world can be helpful in determining the applicability.

My thoughts also.

See my response to femr2.

The implicit limits are quite strict BUT they have not been made explicit and "we" are currently unsure where they are.

Plus some of us ( at least me ) are mainly interested in WTC 9/11 application not development of generic models.

 

[Major_Tom]

A good example of utter cluelessness:

Seymour Butz to me, page 14 of the OOS model thread, post #522:

"Seriously now, it's been pointed out that you're misrepresenting Bazant's papers.

The crush up/down thing STILL refers to the idealized case of the strength of the columns, not the floors, being the determining factor in his equations.

There's more examples of your twoofiness available to any who care to waste their time pointing them out to you.

If you can't admit that, there's zero reason to engage you seriously. Instead, it is appropriate to ridicule you if you cannot.

This is what you deserve."

Link to post http://www.internationalskeptics.com/forums/showpost.php?p=6033382&postcount=522

Notice that most every example of the misapplication of crush down, then crush up to real towers and freely mixing the BZ (2002) paper and the BV (2007) paper with no regard to the differing purpose of each paper given in this thread contain insults to me over my "stupidity" and "troofiness', while the posters remained ignorant of their own false statements.

This is why many people associate this forum with propaganda, not honest debate.

 

[beachnut]

A good example of utter cluelessness:

...

This is why many people associate this forum with propaganda, not honest debate.

You think you can debate CD; it is a delusion. You must debate the delusions you have on 911 at a forum where delusions are accepted, not a skeptics forum. You think your delusion is real, this is why you call rational thinking and evidence propaganda. After 8 years, you have failed, you are not good at figuring out 911.

You have to debate your CD delusion at other forums, skeptics require proof and evidence; things you never provide.

You have shown you can't handle real engineering models by attacking Bazant's model. Publish your nonsense and delusions, and find confirmation of your CD theory.

 

[ozeco41]

...Notice that most every example of the misapplication of crush down, then crush up to real towers and freely mixing the BZ (2002) paper and the BV (2007) paper with no regard to the differing purpose of each paper given in this thread contain insults to me over my "stupidity" and "troofiness', while the posters remained ignorant of their own false statements....

The strong polarisation is disappointing but nothing you say is likely to change it. Since you are painted into the truther camp your attempts to discuss legitimate issues are being swamped by the high "noise to signal" reactions to your perceived truther position.

...This is why many people associate this forum with propaganda, not honest debate.

Whether the generalisation is true or not I don't think that making the statement will gain you any friends.

 

[pgimeno]

A good example of utter cluelessness:

Seymour Butz to me, page 14 of the OOS model thread, post #522:

"Seriously now, it's been pointed out that you're misrepresenting Bazant's papers.

The crush up/down thing STILL refers to the idealized case of the strength of the columns, not the floors, being the determining factor in his equations.

There's more examples of your twoofiness available to any who care to waste their time pointing them out to you.

If you can't admit that, there's zero reason to engage you seriously. Instead, it is appropriate to ridicule you if you cannot.

This is what you deserve."

Link to post http://www.internationalskeptics.com/forums/showpost.php?p=6033382&postcount=522

Notice that most every example of the misapplication of crush down, then crush up to real towers and freely mixing the BZ (2002) paper and the BV (2007) paper with no regard to the differing purpose of each paper given in this thread contain insults to me over my "stupidity" and "troofiness', while the posters remained ignorant of their own false statements.

I've been trying to match Seymour Butz's comment with your interpretation, to no avail. I've even checked the context in which that was said, to see if there's a reference to [BZ] which I missed.

I'm failing to see how Butz's comment makes any reference to [BZ] whatsoever. Please explain (or accept his conclusion on the ridicule you deserve).

 

[Myriad]

Apparently it's somehow improper to refer to information originating from more than one paper when writing a post.

Who knew? It must be something like the injunction in Leviticus about mixing linen and wool in the same garment.

Respectfully,
Myriad

 

[ergo]

Every decent 9/11 researcher from both sides of the fence can agree that the original initiation of each collapse and the events leading to it are perhaps the only time period in which an intentional demolition and a natural collapse are distinguishable.

Like who, for example?

Controlled demolition and natural collapses (which, for one thing are always partial, except for perhaps earthquake-hit structures) look very different. Not only that, but the Twin Towers' disintegration resembles neither natural collapse nor typical CD.

It is foolish to miss this point and associate a careful study of the collapse initiation sequences of each building with claims of space beams, freefall for all 3 towers and no planes.

Well, now you're the one creating strawmen.

 

[Major_Tom]

Pgimeno and Myriad, you still cannot see the difference between the ideal case of a single impact with assumptions most optimaol for survival of the building in BZ (2002) and the derivation of equations of motion to be used to predict the motion of real buildings in BV (2007)?

If you mix the 2 arguments, then you must be totally lost when reading BV, BL and BLGB.

Besides Ozeco, is there anyone in this forum that can spot the mistake Myriad keeps making?

The modified BV equations of motion applied to WTC1 and 2 in BLGB:

Myriad and Pgimeno, why do you think Bazant is showing how WTC1 and 2 data points match his crush down equation of motion originally derived in BV?

If your reasoning is correct, then the data points should descend faster than what you believe are equations of motion for an idealized case with assumptions most optimal for survival.

Do you really believe the BV equations of motion are intended to represent motion of the slowest possible descent of a building under conditions most optimal for survival?

Is he trying to match motion of real buildings of just derive a theoretical upper limit of the slowest possible descent?

No need to guess. Just read the introduction and conclusions of BV.

No need to guess, just watch how he applies the equations to WTC1 in BLGB.

 

[beachnut]

Pgimeno and Myriad, you still cannot see the difference between the ideal case of a single impact with assumptions most optimaol for survival of the building in BZ (2002) and the derivation of equations of motion to be used to predict the motion of real buildings in BV (2007)?
....

The cool thing about you guys with the CD delusion, when you publish your ideas in a real journal, they get comments like nonsense and delusional. Publish your junk and prove me wrong. Take some action.

BTW, Bazant's model is applicabliby to the real world. Bazant's model can be used to identify people who don't understand the real world and engineering models. Publish your claims in a real journal. Is your CD delusion based on thermite or explosives? Your model is not applicable to the real world because you have no evidence for your CD claims. 2 days and it will be 9 years, and Bazant's model was done in two days. How many more days before you publish your model? Heiwa got his letter published, why can't you do something more than attack Bazant? Any plans on going to engineering school? Which school will you pick? Good luck publishing your fancy fake engineering ramblings.

Why not shoot your post off to the journal like Heiwa did with his letter?

 

[pgimeno]

Pgimeno and Myriad, you still cannot see the difference between the ideal case of a single impact with assumptions most optimaol for survival of the building in BZ (2002) and the derivation of equations of motion to be used to predict the motion of real buildings in BV (2007)?

I don't see the relation between that and Seymour Butz's statement that the crush-up/crush-down was related to the strength of the columns, not the floors, being the determining factor. This is the relevant part of the quote into play:

The crush up/down thing STILL refers to the idealized case of the strength of the columns, not the floors, being the determining factor in his equations.

And that is indeed the case in [BV]. How is that related to [BZ]?

The whole quote is here, for you to see that in its context:

Seriously now, it's been pointed out that you're misrepresenting Bazant's papers.

The crush up/down thing STILL refers to the idealized case of the strength of the columns, not the floors, being the determining factor in his equations.

There's more examples of your twoofiness available to any who care to waste their time pointing them out to you.

If you can't admit that, there's zero reason to engage you seriously. Instead, it is appropriate to ridicule you if you cannot.

This is what you deserve.