OOS Collapse Propagation Model

[JSanderO]

The inward bowing came before the buckling. I don't believe anyone claims the trusses caused the exterior columns to buckle, they just helped get the process started.

My read of the link was the the IB was initiated by pulling of the facade... then came the buckling.

I contend that there was little to no inward pull by the trusses... and it was ALL buckling. This is supported by the gif I posted. You don't see that?

 

[DGM]

My read of the link was the the IB was initiated by pulling of the facade... then came the buckling.

I contend that there was little to no inward pull by the trusses... and it was ALL buckling. This is supported by the gif I posted. You don't see that?

Why did they all start bowing in the same direction. Bowing -> buckling, the trusses provided the pull needed to cause the columns to buckle under load.

 

[JSanderO]

This is off-topic and has been discussed and analyzed ad infinitum over the past 13 years.
The topic here is what happened after the initial event; i.e., from t=0+e onwards.

Not really... isn't the topic OOS propagation model? Why is the initiation or transition to propagation off topic?

Perhaps you can define exactly what was the state of the tower at your T=0 moment in time?

 

[JSanderO]

Why did they all start bowing in the same direction. Bowing -> buckling, the trusses provided the pull needed to cause the columns to buckle under load.

Because there was a moment caused by the weight of the floors... perhaps?

 

[rwguinn]

Not really... isn't the topic OOS propagation model? Why is the initiation or transition to propagation off topic?

Perhaps you can define exactly what was the state of the tower at your T=0 moment in time?

Propagation is the process that occurs AFTER initiation

 

[JSanderO]

Propagation is the process that occurs AFTER initiation

fine... so answer my question if you can.. what was the state of the building and its components at your t=0?

I know that there are some distinct features or attributes of the collapse phase nicked named ROOSD.

But there was a sort of phase transition and I would assert that there is effectively no T=0 and that might just be an arbitrary time where the first roofline movement is observed. But clearly there was action within from plane strike to T=0 and this is very much linked to ROOSD or created the so called ROOSD mass... n'est pas? Or is this wrong?

 

[DGM]

Because there was a moment caused by the weight of the floors... perhaps?

There certainly was, and this was transferred to the columns by the trusses. The weight was always there. Trusses are known to sag when heated, this would pull on the exterior columns causing them to lose capacity (and fail by buckling). The pull by the floor trusses was just the start. Soon the pull was too much and failed the connection which was the beginning of the end.

 

[Newtons Bit]

Mr Bit... could you respond to my points about the so called pull in of the facade... the explanation of which you felt was in the links. This may be OT.... and relate more to the initiation than the collapse.

I am not here to argue but to learn.

Please post it in the correct thread and I will.

 

[Newtons Bit]

One of the things engineers have learned over the years is that consistency leads to accuracy.
terms like x, y, and z are axes of a coordinate system. terms like u,v,and w arre also axes of a coordinate system, rotated with respect to x,y, and z. Almost universally, x and y are the plan view as seen from above, with "z" being the vertical axis. (This is so imbedded that all CAD programs I know of start with that assumption).
The variable "t" is, unless otherwise specified, time. A term with "(t)", or "(anything)" after it; e.g., z(t), a(x), is that variable as a function of whatever is inside the (). a "." over a term is the first derivative of that term with respect to time. 2 "."s are the second derivative of that term with respect to time. (Since that is hard to do on a typewriter or word processor, the " ' " has come into use, thus x'=first derivative of distance wrt time (Velocity) and x'' is 2nd derivative (acceleration)
These things are so universally known and taught that any competent engineer can pick up a paper and immediately know just what the hell the other guy is talking about. And just to make sure, virtually all papers have, at the front, a definition of terms section to reiterate this, and to define variables that are used in possibly ways that might not be familiar to the reader.

Doest that assist you in any way, M_T?

Looking back, I'm not sure if Major_Tom is aware that the term z is to define the distance from the top of the upper block to bottom of upper block (or the crush front), and instead thinks it's from the bottom of the building to the crush front. I can't quite tell...

 

[W.D.Clinger]

This is October, 2014. Can anyone besides Ozeco spot any mistakes in BV, BL, or BLGB. This same question was asked about a month ago a number of times and nobody except Ozeco was able to do so.

How quickly he forgets. Two years ago, on 7 June 2012, I wrote:

On my first reading of BV, I found an obvious math error in one of their numbered equations, which led me to find about half a dozen related errors when I read the paper more closely. It turned out that none of those errors were significant, but they reduced my confidence in the quality of the paper and in its peer review process. I'm not inclined to assume the authors got everything right.

That said, I think most of the criticisms that have been levelled in this subforum against their crush-up/crush-down calculations have come from people who understand neither the physics nor the math. So far as I can tell, which isn't very far, that aspect of their papers may be largely correct for their model. As ozeco41 and others have said, however, their model may apply to the WTC collapses in only the most general of terms, if indeed at all. I am not competent to express an opinion on that.

The comedy continues:

It isn't about beliefs 4 years ago. It is about a blind incompetence which has existed for over 4 years, well-documented within this thread, and continues today.

Agreed.

If you click on that link, you will find links that document the blind incompetence. The last of those links takes you to the following remarks, which I posted on 6 January 2011:

You will never review these critically.

Instead, you witch-hunt anyone who pops you bubble of illusion.

If you were a critical thinker, you would correctly criticize NIST and BV, BL and BLGB instead of trying to get me kicked out for posting math without the proper permit.

I have said several times now that one of the numbered equations in BV is incorrect, and obviously so, although the error isn't quite so obvious as any of the 17 errors I have enumerated in your alleged "proof". A glance at BV Figure 3 explains why their error is not significant, and it looks to me as though a half-dozen corrections to BV would repair that error without affecting their conclusions. So far as I can tell, the main problem with BV is the plausibility of their model, which lies outside my competence.

As for the NIST reports, I have contributed to enough group efforts to know how sausage is made. I have absolutely no problem with competent criticism of those reports, and I am aware of a few such criticisms that may be related to some of the points you have been trying to make.

Your own criticism, however:

• rests on faulty assumption
• rests on faulty math
• rests on unsourced material from unknown authors
• fails to convince

Furthermore you have pretended your mistakes don't affect your results or the claimed "mathematical certainty" of your alleged "proof". That tells us you don't understand the concept of a mathematical proof, and it suggests you've been faking or plagiarizing your results.

Yes, a quick glance tells us that the plus sign in the first expression should be minus. Crime.

Yes, the terms for magnitude for the vector difference should have a square root. A quick glance tells us that if vector Q=0, the magnitude of B is b^2. wrong. Crime.

Correction: a quick glance told me of your errors. You couldn't find them in a week.

 

[Newtons Bit]

 

[Oystein]

Looking back, I'm not sure if Major_Tom is aware that the term z is to define the distance from the top of the upper block to bottom of upper block (or the crush front), and instead thinks it's from the bottom of the building to the crush front. I can't quite tell...

Perhaps if M_T were t explain what coordinate system z is measured in - where is z=0, and from which point to which other point does Bz measure z(t)?

It would be most helpful if this could be answered in two simple sentences, in M_T's own words, or better yet with the help of a simple graphic.
Another round of walls of unedited quotes would however NOT be of help for us JREF folks of little brain.

 

[LSSBB]

His implications and conclusions for these equations are clearly listed on page 318:

This one is my favorite:

5. The present idealized model allows simple inverse analysis which can yield the crushing energy per story and other properties of the structure from a precisely recorded history of motion during collapse. From the crushing energy, one can infer the collapse mode, e.g., single-story or multistory buckling of columns.

What do you think it implies for the applicability of the research presented toward whatever case you are trying to make here, M_T? How about towards use in construction engineering?

 

[Major_Tom]

On this subject the participating regulars are truly insane. I am in the thankless position of pointing out inconsistencies to the truly religious concerning their God.

BV is really, really important to some of you and some of you will stop at nothing to believe in it. It is as far as the intellect can stretch within this environment on WTC collapse progression.

The entire thread from page one shows zero capacity to think critically about BV and zero capacity to even perceive anything within the paper's closure, BL. This is not an intellectual exchange, it is an emotional and religious one....to the point of pure, explicit neurosis.

 

[Major_Tom]

Perhaps if M_T were t explain what coordinate system z is measured in - where is z=0, and from which point to which other point does Bz measure z(t)?

It would be most helpful if this could be answered in two simple sentences, in M_T's own words, or better yet with the help of a simple graphic.
Another round of walls of unedited quotes would however NOT be of help for us JREF folks of little brain.

A roofline to crush front, which is a really stupid idea if a person has the capacity to think about it. The WTC roofline ceased to exist very early into the collapse, but Bazant to this day has never recognized this reality in writing.

Seffen used the wrong form of crush front interaction, but at least he never wrote anything as stupid as suggesting an intact, existing roofline for the WTC1 and 2 collapse progressions.

He also never developed a cult following that I know of like the one seen here.

 

[Major_Tom]

Looking back, I'm not sure if Major_Tom is aware that the term z is to define the distance from the top of the upper block to bottom of upper block (or the crush front), and instead thinks it's from the bottom of the building to the crush front. I can't quite tell...

Crush front. Upper block doesn't change in height during the entire crush-down process.

Three zones, NB. Zones A, B and C. Zone C is called "upper block". "Upper block" never changes in height until "crush-up".

Even Heiwa was able to figure out that part 6 years ago.

 

[Oystein]

A roofline to crush front,

Thanks.

which is a really stupid idea if a person has the capacity to think about it. The WTC roofline ceased to exist very early into the collapse, but Bazant to this day has never recognized this reality in writing.

Well, isn't his model 1D? In a 1D-model, the roof-top is a mathematical point, and there is always going to be a well-defined point on top of the model-block-C.
Just saying. Makes sense in the context of the model, I think.
I am not saying it makes literal sense in 3D-reality. Would depend on what you use the model for. I am personally not using it for anything at all, so please resist the urge to make your reply about me.

Crush front. Upper block doesn't change in height during the entire crush-down process.

Three zones, NB. Zones A, B and C. Zone C is called "upper block". "Upper block" never changes in height until "crush-up".

Even Heiwa was able to figure out that part 6 years ago.

It really wasn't clear from your long walls of quotes whether YOU were able to figure it out. Your wording ("z(t) is the crush front") was too sloppy to discern what you were talking about.

I suggest you cut back the long tracts of copy&paste and add a little of your own words, explannations, perhaps someone will then actually read what you write.

...
He also never developed a cult following that I know of like the one seen here.

To me, you are the cult I am following

On this subject the participating regulars are truly insane. I am in the thankless position of pointing out inconsistencies to the truly religious concerning their God.

Splinter in your neighbour's eye...
In a very similar, and perhaps more annoying, way, you ignore when someone points out the error's in your own work. This kinda invites resistance to corrections coming from you.
Just saying.

BV is really, really important to some of you

I am not my brother's keeper, and am not privy to my fellow posters' minds and priorities, but my perception on this point is very different from you: I do not have the impression at all that BV is "important" to anyone at all here. This is the 9/11 Conspiracy Theoories sub-forum. I don't think anyone here has ever used BV to either debunk or support any 9/11 CT, so BV is not important here. I can tell you with utmost certainty that BV is of absolutely no importance to me! I am not here, not in this thread, to debate BV. I am following your work with some mild interest. I thought it interesting when you announced a "mathematical approach to ROOSD" and was disappointed when you did in fact did present NOT a "mathematical approach to ROOSD" but yet another approach to heaping contempt on Bazant and partners.
Just saying.

and some of you will stop at nothing to believe in it. It is as far as the intellect can stretch within this environment on WTC collapse progression.

The entire thread from page one shows zero capacity to think critically about BV and zero capacity to even perceive anything within the paper's closure, BL. This is not an intellectual exchange, it is an emotional and religious one....to the point of pure, explicit neurosis.

Pot ... kettle...
See, this "exchange" is not about Bazant. You make it about "us" (as if we were a monoculture), and "we" make it about "you".

How about you stop the psychologizing and start working on a mathematical approach to ROOSD?
I think everyone here more or less accepts ROOSD as an apt verbal description of collapse progression, and perhaps you'd even get some help formulation a math description, if you asked for it politely.

Just saying: Change your focus, change your attitude, define your objectives, and you might win this thread.

 

[tsig]

On this subject the participating regulars are truly insane. I am in the thankless position of pointing out inconsistencies to the truly religious concerning their God.

BV is really, really important to some of you and some of you will stop at nothing to believe in it. It is as far as the intellect can stretch within this environment on WTC collapse progression.

The entire thread from page one shows zero capacity to think critically about BV and zero capacity to even perceive anything within the paper's closure, BL. This is not an intellectual exchange, it is an emotional and religious one....to the point of pure, explicit neurosis.

That strawman is worn thin to the point of transparency. It is in fact a dead strawman.

 

[Newtons Bit]

Perhaps if M_T were t explain what coordinate system z is measured in - where is z=0, and from which point to which other point does Bz measure z(t)?

It would be most helpful if this could be answered in two simple sentences, in M_T's own words, or better yet with the help of a simple graphic.
Another round of walls of unedited quotes would however NOT be of help for us JREF folks of little brain.

I would be very surprised if he did.

 

[Newtons Bit]

A roofline to crush front, which is a really stupid idea if a person has the capacity to think about it.

So you're agreeing with me now? I can't tell with you anymore.