Merged Applicability of Bazant's model to the real world

[pgimeno]

I wrote this May 17th of last year, a few days after I started posting, and have repeated it many times before and since then:




Here are some basic questions I asked repeatedly since May:


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 BL, equations 12 and 17, to be accurate considering the information in the ROOSD study?

3) Is the following statement true or false:

Dr Bazant believes that a crush-down phase must continue to completion before a crush up phase can begin.

If you answer false, please provide evidence to the contrary.

4) Is ROOSD consistent the claims of crush down preceding crush up in BV and BL?



5) Consider from BL:

"So it must be concluded that the simplifying hypothesis of
one-way crushing (i.e., of absence of simultaneous crush-up),
made in the original paper, was perfectly justified and caused
only an imperceptible difference in the results. The crush-up
simultaneous with the crush down is found to have advanced
into the overlying story by only 37 mm for the North Tower
and 26 mm for the South Tower. This means that the initial
crush-up phase terminates when the axial displacement of
columns is only about 10 times larger than their maximum
elastic deformation. Hence, simplifying the analysis by neglecting
the initial two-way crushing phase was correct and
accurate."

What does he mean by these claims? Do you really believe this claim?


6) Or how about this from BL:

"Blocks C and A can, of course, deform. Yet, contrary to
the discusser’s claim, they may be treated in calculations as
rigid because their elastic deformations are about 1,000 times
smaller than the deformations at the crushing front."

This is how Dr Bazant justifies the survival of the upper block until reaching earth in BL

Do you honestly believe this claim?

I have already give enough explanations along this thread as for my answers to be clear, but I don't care to do it just once more and directly.

1. He is describing his model. Yes, he means it literally, in his model. Not in how the towers behaved in reality.

2. Yes, they are accurate for his model. Consideration of that study is totally irrelevant, since it doesn't deal with Bazant's model at all.

3. Impossible to say what he believes. However, in case he believes that "a crush-down phase must continue to completion before a crush up phase can begin" in the precise case of how the WTC towers behaved, it has become obvious by now that he doesn't state so in any of the papers. Each and every instance where you brought a citation, it turned out to be a description of the behavior of the model. Therefore, it corresponds to you to bring a citation where he is talking about the behavior of the real buildings, as opposed to the behavior of the model when the parameters of WTC1 and WTC2 are applied to it.

4. ROOSD is NOT a mathematical model, therefore, it's apples and oranges.

5. From the context, which you've trimmed, it's crystal clear that he's discussing how the model behaves when the parameters of WTC1 and WTC2 are applied to it. From that standpoint, I of course believe it's an accurate description of how his model behaves when these parameters are applied.

6. Again, a description of the behavior of the model, and as such, I honestly believe it. What's wrong with that description? The entire BL paper is a description of the behavior of the model when the WTC1 and WTC2 parameters are applied to it. Nothing surprising in any of the quotes you bring.

>>>>>>>>>>>

TFK bragged about his superior capacity to understand these papers. I predicted he'd fall on his face when trying to answer basic questions about the papers.

We're still waiting, cowboy. Please demonstrate your superior capacities by just answering the questions rather than by providing your resume.

He already did. You must have missed it.

http://www.internationalskeptics.com/forums/showpost.php?p=6806162&postcount=1588

 

[femr2]

3. Impossible to say what he believes.

Sure.

However, in case he believes that "a crush-down phase must continue to completion before a crush up phase can begin" in the precise case of how the WTC towers behaved, it has become obvious by now that he doesn't state so in any of the papers. Each and every instance where you brought a citation, it turned out to be a description of the behavior of the model. Therefore, it corresponds to you to bring a citation where he is talking about the behavior of the real buildings, as opposed to the behavior of the model when the parameters of WTC1 and WTC2 are applied to it.

What do you make of...

The aforementioned distance of initial crush-up would be larger if the column cross sections changed discontinuously right below or right above the first collapsed story. However, this does not appear to be the case.

Any issue with the following interpretation...

"The aforementioned (calculated) distance of initial crush-up would be larger if the column cross sections (in the real building) changed discontinuously right below or right above the first collapsed storey (in the real building). However, this does not appear to be the case (in the real building)...(therefore the distance of initial crush-up is not larger.)"

The author is writing from a position somewhat in limbo between the virtual and real worlds, if you ask me (which you're not) but there you go anyway

 

[femr2]

Whilst I have the doc open...

Since the velocity of the crushing front near the end of North Tower crush-down is, according
to the solution of Eq.(2), z =47.34m/s (106mph), the velocity of escaping air near the end of crush-down is...

...most certainly NOT what they calculate it to be (up to mach 1 !), as the primary North Tower crush front traversed at a fairly constant ~28m/s.

Their nearby assertion...

This must, of course, create sonic booms, which are easily mistaken for explosions

It's great isn't it. There is this model that the authors would not dream of incorrectly applying to reality, yet we have the virtual crush-down velocity (which is wrong) being used to determine the velocity of air escaping (which is also wrong) used to highlight the source of some explosions they heard tell of.

Genius

They continue...

There are other phenomena that can cause v_a to differ from the estimate in Eq.(8)

Too right there are, like the base model being the limiting case, and the real behaviour and mode of destruction being entirely different. Come on guys, back in the real world...

what matters is the simple fact that the air must, in one way or another, get expelled from each story of the tower within a very short time interval, which is only 0.07s near the end of crush-down of North Tower.

...er, guys, no, it's not.

(bolding and emphasis mine, of course )

Now these guys may not be technically talking about the real world(if you want to be pedantic with words) but the bottom line is the conclusions drawn and the solutions given, which are a) wrong and b) being used to justify factors in the real world to which they just don't apply...because they are wrong.

I could go on for hours with BLGB alone...zzzz

Oh, wait...

The high velocity of air jetting out also explains why a large amount of pulverized concrete, dry walls and glass was ejected to a distance of several hundred meters from the tower (Fig.3a).

...how many references to *the tower* in the real world do we need eh

That's Fig. 3a btw.

Is that tower somehow different to all the other tower pictures ? Because the authors are most definitely referring to the real towers pulverized concrete, dry walls and glass.

Anyway, ...

 

[W.D.Clinger]

3. Impossible to say what he believes. However, in case he believes that "a crush-down phase must continue to completion before a crush up phase can begin" in the precise case of how the WTC towers behaved, it has become obvious by now that he doesn't state so in any of the papers. Each and every instance where you brought a citation, it turned out to be a description of the behavior of the model. Therefore, it corresponds to you to bring a citation where he is talking about the behavior of the real buildings, as opposed to the behavior of the model when the parameters of WTC1 and WTC2 are applied to it.

Bažant and Verdure were very clear on the status of their crush-up before crush-down abstraction: It's a deliberate simplification of reality, justified by the following:

• In their model, the physics of the crush-down phase imply the amount of crush-down is greater than the amount of crush-up. That's a consequence of the homogeneity, gravity, and the simple fact that the mass of section A plus B is always greater than the mass of section B A.
• In the motivating example of the WTC towers, the amount of crush-down that occurs during the crush-down phase of their model must dominate the amount of crush-up. That's obvious because the initial size of section A is less than the initial size of section C, section C was completely crushed, and the crush-down phase is defined to be the duration of section C's crushing.
• Crushing is assumed to occur only after some threshold for elastic deformation has been exceeded. Combining that with the fact that the crushing force is always greater at the lower crushing front than at the upper, that threshold amplifies the disparity between crushing at those two fronts beyond what would be expected without any threshold.
• Bažant and Verdure may appear to believe the threshold is pretty large because they still discuss their model in terms of one of the optimistic assumptions from Bažant and Zhou: that all of the impact forces go into the columns. So far as I can tell, however, that assumption is not part of the mathematical model in BV. A large threshold would increase the dominance of crush-down over crush-up during the crush-down phase, but crush-down would predominate even without a large threshold.
• Any disintegration of the upper section A that occurs for reasons other than crush-up during the crush-down phase would increase the predominance of crush-down over crush-up during the crush-down phase, thereby improving the model's assumption that crush-up is negligible during the crush-down phase.
• The crush-down before crush-up simplification of the BV model continues to apply even if there is nothing left of section A by the end of the crush-down phase. In that case, the crush-up phase happens to be trivial, with zero duration.

Disintegration of upper section A during the crush-down phase might lead to non-uniform lateral shedding, which could interfere with the model's assumption that all lateral shedding can be absorbed into a constant compaction ratio λ. So far as I can tell, that's the main problem the BV model might have with disintegration of section A during the crush-down phase.

There are a couple of people here who seem to think any disintegration of section A during the crush-down phase would invalidate the BV model's assumption that crush-up can be neglected during the crush-down phase. So far as I can tell, that's completely nuts.

Standard disclaimer: I am not an engineer. If some qualified person is willing to point out my mistakes, I will listen.

Sometimes I listen to unqualified persons who clearly don't know what they're talking about, but I'm likely to tune them out eventually if they disregard criticism of their errors or refuse to explain salient points of their argument(s).

 

[tfk]

TFK bragged about his superior capacity to understand these papers. I predicted he'd fall on his face when trying to answer basic questions about the papers.

We're still waiting, cowboy. Please demonstrate your superior capacities by just answering the questions rather than by providing your resume.

Major_T,

You promised to explain to anyone who asked the details of the BZ & BV papers. To walk them thru the equations.

I must have missed that.

Could you please provide a link to your explanations. I went back & looked, but could not find them.

tk

 

[tfk]

Since Bazant wrote his papers some researchers have actually mapped real WTC1 collapse progression rates for the first time.

http://femr2.ucoz.com/_ph/6/2/760729846.gif

http://femr2.ucoz.com/_ph/6/2/730189522.jpg

Please provide your arguments / evidence that this is collapse progression & not pressure wave progression.

Please explain why, if this is collapse progression, there appears to be an un-collapsed corner of the building (vertical light streak = chamfered corner of the building) that remains standing for many floors after collapse wave has passed by.


tk

 

[ozeco41]

...1. He is describing his model. Yes, he means it literally, in his model. Not in how the towers behaved in reality...

I acknowledge your premise - that there is a clear distinction between 'model' and 'real world' - and note that the OP is "Applicability to...real world'.

I also see that you attribute all or most of Bazant's references to WTC as applying the parameters of WTC to the Bazant model(s). Let's accept that for purposes of discussion.

So at the very least your position has a clear distinction between 'model' and 'real world'. And I draw the distinction between your position which is 'Bazant applied WTC to the model' and the alternate position which is 'applying the model to real world'. The reversal is significant.

...4. ROOSD is NOT a mathematical model, therefore, it's apples and oranges....

actually a poor analogy because it implies more than it can support. ROOSD is not an irrelevant consideration. It is a base explanation of a collapse mechanism just as Bazant's assumptions of a collapse involving 'homogeneous' blocks with columns offering resistance and no distinction between core, OOS, outer columns. That is the base for Bazant's model - not the base in the real world.

So Bazant builds such maths as he requires on the model he chooses. Major_Tom is exploring the real world and he defines his collapse mechanism which just happens to correspond with the most commonly accepted model. Don't be thrown by the ROOSD terminology. Recall babies and bathwater. ROOSD is the base for the real world, not the base for Bazant's model.

...The author is writing from a position somewhat in limbo between the virtual and real worlds, if you ask me (which you're not) but there you go anyway

Yes. And right in the territory which this threads OP set out to discuss.

I won't, at this stage, enter into the difference between pgimenos position and yours - i.e. how much is Bazant applying WTC parameters to a model and not imposing the model on the real world.

Bažant and Verdure were very clear on the status of their crush-up before crush-down abstraction: It's a deliberate simplification of reality, justified by the following.....That's a consequence of the homogeneity, gravity, and.....

My emphasis and the remainder of the post clearly derived from the 'model' perspective rather than 'fit to the real world.

No conclusions on the OP emerging yet but we have a clear distinction 'model' to 'real world' and some differing views as to where the line is drawn.

 

[rwguinn]

I'm going out on a limb, on the crush-up/Crush-down BS.
The model was a simplification. as such, it makes an assumption (clear to me, but I have been mistaken at one time or another) that at some point, the resultant debris cloud is sufficient to sustain the collapse, simply from dissipation of KE into the standing structure, and the remaining upper block is simply riding that cloud as a passenger, with little energy dumping back in to it.
At that point, crush-up stops, until the sudden stop at the bottom.
yes, it's a simplification. Yes, parts of the core remained standing, for a brief period. That would have a reflection on the reality of the collapse, but is not accounted for in the simplified model.
Does that help?

 

[W.D.Clinger]

Bažant and Verdure were very clear on the status of their crush-up before crush-down abstraction: It's a deliberate simplification of reality, justified by the following.....That's a consequence of the homogeneity, gravity, and.....

My emphasis and the remainder of the post clearly derived from the 'model' perspective rather than 'fit to the real world.

Yes, and I'll remind you and other readers once again that the model is one-dimensional so its assumed homogeneity is vertical.

No conclusions on the OP emerging yet but we have a clear distinction 'model' to 'real world' and some differing views as to where the line is drawn.

With respect to the model's assumption of vertical homogeneity, I see two possible problems with applying that assumption to the WTC towers:

• The mechanical floors might have been different enough to matter.
• Differential collapse rates between the core and the area outside the core, if combined with significant interactions between the two, could conceivably invalidate the assumption of vertical homogeneity.

If I understand you correctly, your objection to vertical homogeneity may be based upon the second of those problems. If so, that's really a problem with the one-dimensionality of the model.

 

[tfk]

Major Tom,

My debate strategy is pretty clear. I have been following this general pattern:

a) First, Introduce a correct collapse propagation theory.
...
Knowledge and observation of the ROOSD process allow us to be specific when "debating" unlike any time previously.
...
Knowledge of the ROOSD process destroys many of those illusions, allowing us to talk about specific features of collapse with a common underlying understanding for the first time.

You seem to have skipped this step, and been mired down in attempting to disprove Bazant et al.

Please provide a link to your "correct collapse propagation theory".

Who are the authors of this "ROOSD theory"?
Where was it published?
When was it published?

Is this is your "ROOSD study" publication?

Do the postings that follow constitute your peer review?

I would point out that the vast, vast majority of engineering publications contain things called "equations". I did a quick search on that page for the one dead give-away of equations: "=". I found lots of those. All of them in urls. Those don't count.

When I searched for " = " (with spaces), zero.
When I searched for "equals", zero.

In engineering, there is a difference between a story and a theory.

b) Second, destroy the most common illusions that put a stranglehold on true, honest debate. For regular posters at JREF, this illusion is that some accepted authority has provided convincing answers to the demolition question.

The heart of this belief in such scientific authority is an attachment to the claims of "proof" by Dr Bazant and the NIST.

Please be specific.
Please speak for yourself.

Bazant's proof of "what".
NIST's proof of "what".
Exactly.

You attempt to make points by being blatantly vague.
Not good.

Many posters are convinced that mechanisms of collapse of all three towers have been identified.

This is totally untrue. The collapses of all three towers remain a total mystery, and no scientific authority has come close to solving or explaining the mystery.

Cause of collapse is different from mechanism of collapse initiation is different from mechanism of collapse progression.

You attempt to leverage "vague".
You fail at that.

This is a fact that many here will fight to deny: The true causes for the collapses of all 3 towers remains unknown. In reality, the NIST was not able to identify the causes of any of the collapses.

No mechanism of collapse has yet been correctly identified

NIST disagrees.
Dr. Bazant disagrees.
I disagree.

My version:
Ultimate cause of collapse = hijacked airplanes flown into building.
Cause of collapse initiation = damage, heat, load shifting, creep, buckling, fracture of many connections.
Cause of collapse progression = massive overload of 10 of thousands of welds & connections.

That's my version. Simple. Sweet.

Please provide your version. Not "questions to my version". Your version.

Please fill in the blanks:
Ultimate cause: ___________
Cause of collapse initiation: __________
Cause of collapse progression: __________

Speaking of illusions, to be fair, many claims by 9/11 truth groups are verifiably incorrect and these illusions must also be destroyed. The researchers that I feel have contributed most to 9/11 resreach have been largely ignored by the mainstream 9/11 truth movement.

"Researchers" like your "dear Max Photon"?

c) … we will debate collapse features more clearly and specifically, maybe for the first time.

No hurry, of course.

After all, it's not as if it's been almost a decade since the event...

… We will find that a knowledge of the ROOSD process will give us a much better ability to see the collapse processes as a whole. We will also notice that many subtle features are seemingly inexplicable even with a knowledge of ROOSD.
…

If you know about the possibility of a ROOSD process, then you have a great advantage …
It's a great help.
There are certain areas that cause natural discontinuities for the ROOSD process, like mechanical room floors, for example, that the observant researcher will want to study in detail.

Lemme guess. "ROOSD" is your baby…?

In this thread I am working on part "b", destroying common illusions.

Wouldn't want to rush into "… debate collapse features more clearly and specifically, maybe for the first time", wouldja?

 

[tfk]

I'm going out on a limb, on the crush-up/Crush-down BS.
The model was a simplification. ...

Your limb is strong.


tom

 

[femr2]

Please provide your arguments / evidence that this is collapse progression & not pressure wave progression.

Please explain why, if this is collapse progression, there appears to be an un-collapsed corner of the building (vertical light streak = chamfered corner of the building) that remains standing for many floors after collapse wave has passed by.


tk

Surely you already know the answers to these questions ?

Your limb is strong.

I suggest you continue that discussion with rwguinn via PM.

 

[tfk]

Please provide your arguments / evidence that this is collapse progression & not pressure wave progression.

Please explain why, if this is collapse progression, there appears to be an un-collapsed corner of the building (vertical light streak = chamfered corner of the building) that remains standing for many floors after collapse wave has passed by.

Surely you already know the answers to these questions ?


I suggest you continue that discussion with rwguinn via PM.

Yup.

Didn't expect an answer.

Never mind. I ain't got the time for your juvenile games.

Your limb is strong.

I suggest you continue that discussion with rwguinn via PM.

When I suggested recently that someone "kiss my lily white [posterior]", I found myself on the receiving end of a warning. And I promised the moderators that I'll be good from now on & not do that again.

So I will NOT suggest that you "kiss my lily white [posterior]".

I will suggest that you have enough difficulty managing your own conversations around here to be attempting to manage anyone else's.

 

[femr2]

Please provide your arguments / evidence that this is collapse progression & not pressure wave progression.

Please explain why, if this is collapse progression, there appears to be an un-collapsed corner of the building (vertical light streak = chamfered corner of the building) that remains standing for many floors after collapse wave has passed by.

Surely you already know the answers to these questions ?

Yup.

Didn't expect an answer.

Never mind. I ain't got the time for your juvenile games.

Well you'll be getting an answer regardless.

As you already know the answers, please spend 30 seconds affirming the following, and I'll post a plethora of supporting info...

1) It is collapse progression, SW crush front, correct ?
2) ROOSD leaving trailing perimeter, correct ?

 

[ozeco41]

Yes, and I'll remind you and other readers once again that the model is one-dimensional so its assumed homogeneity is vertical...

The terminology 'homogeneity is vertical' tends to throw me. I would tend to call it 'assumed homogeneity horizontally across the building'. My pedantry aside - YES I agree.

With respect to the model's assumption of vertical homogeneity, I see two possible problems with applying that assumption to the WTC towers:

• The mechanical floors might have been different enough to matter.

Could but the collapse videos don't seem to reveal any hiccups. Femr2 et al may have done some measuring. I'm content to leave it aside at this stage of discussion.

• Differential collapse rates between the core and the area outside the core, if combined with significant interactions between the two, could conceivably invalidate the assumption of vertical homogeneity.

My central point. I have said so in different words and with near certainty. Unless there is something in the Bazant maths which has eluded me - I think it unlikely.

...If I understand you correctly, your objection to vertical homogeneity may be based upon the second of those problems. If so, that's really a problem with the one-dimensionality of the model.

Both "YES". However another difference of perspective in that I would say "The model does not fit what really happened". Hence "The model does not apply to some aspects of the real world WTC collapses." Word meaning pedantry of little consequence at this stage of discussion I think.

 

[ozeco41]

I'm going out on a limb, on the crush-up/Crush-down BS.
The model was a simplification. as such, it makes an assumption (clear to me, but I have been mistaken at one time or another) that at some point, the resultant debris cloud is sufficient to sustain the collapse, simply from dissipation of KE into the standing structure, and the remaining upper block is simply riding that cloud as a passenger, with little energy dumping back in to it.
At that point, crush-up stops, until the sudden stop at the bottom.
yes, it's a simplification....

All of your post so far is in complete agreement with my understanding of the model.

...Yes, parts of the core remained standing, for a brief period. That would have a reflection on the reality of the collapse, but is not accounted for in the simplified model.
Does that help?

True that 'the reality of the collapse...is not accounted for in the simplified model'.

However the 'parting of the ways' between model and reality starts back at the beginning of the collapse progression or 'global collapse'. The collapse progression can validly be seen as three nearly coincident collapses involving separate but related mechanisms. The collapse of the open office spaces leading in time. The outer tube columns attested by video evidence seen to fall away after the floors have collapsed at that level. The core probably being stripped down later than the open office space as indicated by but not proved by the 'spires' which fell some seconds later.

So a key element of discussion is whether or not the Bazant model(s) which presume homogeneity can accommodate the known three separate parts of mechanism of the actual real world collapse(s).

 

[tfk]

femr,

What a clusterfork.

I ask a simple question.

You claim that I already know the answer. You're wrong.

I say "never mind. I don't have time for your shenanigans."

You reply:

Well you'll be getting an answer regardless.

But you don't supply an answer.

And you have the gall to question why I (& others) say that dealing with is a royal pain in the ass...

As you already know the answers…

Please don't presume to know what I do & don't know.
You're wrong.
I've never looked at this before.

please spend 30 seconds affirming the following, and I'll post a plethora of supporting info...

1) It is collapse progression, SW crush front, correct ?

I haven't the slightest idea what that gif is. It's your gif. And when MT posted it, he also didn't identify it.

2) ROOSD leaving trailing perimeter, correct ?

"Table eating chocolate coffee, right?"

Your phrase is not a sentence. The phrase makes no sense.
Please construct a non-gibberish sentence.

Or just answer the farkin' questions.

1. How do you know that the smoke blowing out of the building is the collapse front & not merely a high pressure front?

2. If you assert that the emitted smoke is the collapse front, why does it appear that the chamfered corner of the building is still in place several floors above the "collapse front"?

See, complete questions.

It ain't that hard.

 

[W.D.Clinger]

The terminology 'homogeneity is vertical' tends to throw me. I would tend to call it 'assumed homogeneity horizontally across the building'. My pedantry aside - YES I agree.

It's not a matter of pedantry, but a matter of communicating what you mean.

The Bažant et al model(s) don't assume "homogeneity horizontally across the building". They can cope with any kind of horizontal inhomogeneity that can be amortized within the parameters of their model(s), and it's fairly easy to give plausible examples of such. That's why people who wish to argue against the applicability of their model(s) have to do more than point out that the WTC towers weren't homogeneous in the horizontal direction; they must also explain how that horizontal inhomogeneity can lead to a vertical inhomogeneity or to some other violation of a model's explicit or implicit assumptions.

I'm inclined to think that argument can be made, and I'd like to see someone make it. If you believe that argument has already been made, and can point me to that argument, then I'll reciprocate by (1) agreeing with the argument or (2) explaining why I don't find the argument entirely convincing or (3) admitting that the argument is beyond my competence to evaluate. Of course, my response is likely to be some combination of (1), (2), and (3).

 

[femr2]

femr,

What a clusterfork.

You're quite right, but not for the reason you think.

I ask a simple question.

Two questions, that you really should already know the answers to.

You claim that I already know the answer. You're wrong.

No, I asked you...

"Surely you already know the answers to these questions ?"

you replied...

"Yup."

The reason I asked you was to give you the opportunity of looking at the questions, perhaps retract them to save yourself some embarrassment.

But you don't supply an answer.

I again state the correct features, though without supporting info, giving you another opportunity to simply say, yes, that's right, SW crush front, far ahead of trailing perimeter peeling.

Please don't presume to know what I do & don't know.
You're wrong.
I've never looked at this before.

Wow

So, you really have not spent any time looking at the descent of WTC1, cannot identify the most basic of descent features, cannot therefore have a clue about any of the basis of the ROOSD study (or indeed any theory based upon observation of crush-front propogation). Unbelievable.

ozeco41 has even outlined critical details in his post immediately preceeding yours.

I haven't the slightest idea what that gif is. It's your gif. And when MT posted it, he also didn't identify it.

Anyone who has spent even a little time looking at the descent should immediately be able to identify what it refers to. You've made numerous posts in the ROOSD thread, so you have zero excuse. SW crush front is clearly identified.

Your phrase is not a sentence. The phrase makes no sense.
Please construct a non-gibberish sentence.

To you perhaps, but as you are illustrating clearly, you are completely clueless of descent features, and are showing your lack of visual information interpretation skills. How embarrasing.

Or just answer the farkin' questions.

Sure. I'll go very slowly, as you clearly have trouble digesting information and retaining previously provided information...

1. How do you know that the smoke blowing out of the building is the collapse front & not merely a high pressure front?

It's not smoke...

You're looking at region A.

Are you able to see the lower ejecta front from the West face on the images above ?

Would you describe it as smoke ?

Have you ever watched the descent of WTC1 ?

2. If you assert that the emitted smoke is the collapse front, why does it appear that the chamfered corner of the building is still in place several floors above the "collapse front"?

An unbelievable question to be asking Tom. And you are actually serious

Read the ROOSD study.

The crush fronts traverse inside the perimeter, leaving the perimeter destruction trilaing far behind.

I'm going as slowly as I can for you, you know, baby steps.

Does everything make sense to you so far ?

It ain't that hard.

Indeed.

 

[newton3376]

Well...I would say at this point that femr2 and MT have pretty much been thoroughly debunked on the Bazant business.

Similar to the conservation of momentum fiasco that femr2 had a while back...

At this point this is what I am concluding about femr2's and MT's position(s)....feel free to add to this or correct me if I am wrong (only competent people need reply to this):

1. Their position does not account for the limitations Bazant was intending for his model.

2. They focus on minor issues while ignoring the overall engineering picture of not just the model, but the actual collapse itself.

3. Their position rests on dubious conclusions from videos and photographs and fails to consider any contrary evidence and does not include any mathematical calculations at all.

If someone has additions/corrections to my conclusions about the position that the truthers are taking in this thread please feel free to post them.

At this point I'm putting their arguments into the "debunked" category along with every other truther argument I have seen to date.