RFC: Bazant and Zhou Simple Analysis refuted

[bje]

I find it fascinating that the truth movement puts their faith in the notion that the evidence of conspiracy could easily be found in information that cannot possibly be obtained.

It's the nature of the beast. Remember the Truther's main premise: "If there's neither a photo nor video of an event, it didn't happen." Thus, because there's no video nor a photo of the Titanic sinking AA77 hitting the Pentagon, it didn't happen.

 

[GregoryUrich]

Einstein notes of samples of structural parts from the collapse initiation zones:




??? Dustified?


Dave follows with:

Looking at the core columns, NIST's modelling predicts serious damage to a proportion of these also


If you are an investigative body, why theorize when you have access to the crime scene and the structural members being discussed?


Why are we "guessing" collapse initiation 6 years later when both core and perimeter sections contained all the information we needed?

Ok, we have an issue here regarding failure mode. I would like to start a new thread to focus on this issue. My proposal for the OT:

Failure mode in WTC towers

Major Tom has, after a review of 100s and 100s of photos, pointed out that columns (both external annd internal) showing member failure (rupture or buckling) represent a very small minority compared to columns failing at their connections (i.e. welds amd bolts). If there was consensus on this issue it would greatly help further the discussion.

I think it would be useful to split the discussion between collapse initiation and the rest of the collapse. Collapse initiation involved less than 3% of the total number of column members (i.e 3 story, whole pieces of steel or external panels with which the vertical supporting structure was assembled during construction). The rest of the collapse involves the other (more than 97%) column members.

For the 97% question:

If member buckling is an important failure mode then I suggest at least half of the photos should show this. We have seen a number of buckled columns but they are still seem to be a very small minority. If the available photos cover only 10% of the members, we should be able to find 75 different buckled core columns and at least 200 buckled external panels.

Personally I have looked at 100s and 100s of photos, essentially randomly on many different sites and in Joel Myerowitz's book. I haven't seen very many examples of member failure either. Is this really an issue? Or are we just not understanding one another?

My suggestion is that, if there are people opposing this conclusion, to do an honest random sample of 50-100 photos and report back with numbers and sources. We will need to agree on what member failure as opposed to connection failure looks like. Any ideas?

 

[Myriad]

Is this from NIST 1-3c ?

I'm not seeing many reasons. Can you please indicate to what section and pages you are referring?

You mean, you've accused NIST of lying about the steel identification process ("This is the center of the lie") without having examined the relevant documentation of their work? Or even being aware of its existence?

Chapter 3 (which is the main body) of http://wtc.nist.gov/NISTNCSTAR1-3B.pdf]NCSTAR 1-3B describes, item by item, what evidence was available to determine the as-built position of each piece of the recovered steel.

However, rather than skip directly to chapter 3, please read the document from the beginning, so you won't need me to answer your inevitable next question, "why was so little of the steel recovered?"

By the way, you might also notice a few images of buckled, non-straight, core column steel in that document, if you look very carefully. (That is, carefully enough not to miss the large color photographs on pages 6, 40, 41, 42, 43, 44, 45, 77, 78, and 79.)

Respectfully,
Myriad

 

[Norseman]

Norseman writes:

The crumbled up perimeter column looks very much like it was overloaded by the upper block during the collapse initiation.

This type of damage is the rare, rare exception.

You won't find many pieces like that among the debris, almost none.

Yes, of course it is rare since it came from the floor where the collapse initiated in WTC 1. It was weakened by fire, it became overloaded when the progressive collapse that broke off all the columns on floor 98th reached its position close to the north east corner. It was this collapse that allowed the upper block to fall down inside the lower block and completely destroy the whole tower. We should not expect to see this type of damage in the other perimeter columns, because they peeled of the tower when the upper block went down inside the lower block and disconnected the interior floors from the columns. When the exterior walls peeled off they broke up in smaller sections. As expected they failed in the bolt connections when they broke up. If you take your time to study NIST NCSTAR 1-3C you will find that NIST is very well aware of the fact that the exterior columns failed in their bolt connections.

 

[Major_Tom]

Gregory writes:

My suggestion is that, if there are people opposing this conclusion, to do an honest random sample of 50-100 photos and report back with numbers and sources. We will need to agree on what member failure as opposed to connection failure looks like. Any ideas?

I agree. But this requires effort on the part of the observer.

This is always the stumbling-block: Effort and honesty.

I am sorry for posting things in this thread which seem to deviate from the direction you wish to see, Gregory. I didn't have the time to start another thread properly and the questions were related to the Bazant paper.

This is what I suggest for anyone that wants to know: Start a separate photo collection for all the core box columns you see that are not...

1) Remarkably straight

2) Separated from from the others cleanly along their original weld surfaces. (Just look at their ends.)


You will find that the photo album is not that big at all.

You will notice that you have to look past many, many very straight columns with squared-off ends just to find one or two.




It is within this context that the inability to study the actual initiation failure mode by collecting representative columns samples from those areas is shown to be nonsense.

4 core samples collected?

You folks have a deep-seated faith.

I've been surprised to discover how little you actually have by way of evidence.


I believed you had more.


Your defense of such a scant collection of core columns tells the honest reader that you have nothing but a belief system:


Buildings fell, therefore core columns buckled.

 

[Major_Tom]

Norseman writes:

It was this collapse that allowed the upper block to fall down inside the lower block and completely destroy the whole tower. We should not expect to see this type of damage in the other perimeter columns, because they peeled of the tower when the upper block went down inside the lower block

Thanks for giving some kind of failure scenario. Notice how nobody else is repeating this scenario. Your scenario, or floor failure, are about the only possibilities left for people who believe in the OT, considering the general conditions of both core and perimeter columns seen in the rubble.

Considering that mechanical room perimeter columns just below the failure initiation point on WTC 2, east face, were seen unbuckled, speared into the ground and had flew clear over WTC 4, you scenario is at least an attempt to explain what was observed.


3bodyproblem notes in fascination:

I find it fascinating that the truth movement puts their faith in the notion that the evidence of conspiracy could easily be found in information that cannot possibly be obtained.

This info couldn't possibly have been obtained?


???

 

[Newtons Bit]

Major Tom, the reasons why the columns failed in buckling but no large deformities are present in the columns is based on simple engineering principles.



Just do the math. Figure out what bending moments are on the column splice when the column is still elastic. When you figure that out, you'll know why.

 

[GregoryUrich]

Gregory writes:



I agree. But this requires effort on the part of the observer.

This is always the stumbling-block: Effort and honesty.

I am sorry for posting things in this thread which seem to deviate from the direction you wish to see, Gregory. I didn't have the time to start another thread properly and the questions were related to the Bazant paper.

This is what I suggest for anyone that wants to know: Start a separate photo collection for all the core box columns you see that are not...

1) Remarkably straight

2) Separated from from the others cleanly along their original weld surfaces. (Just look at their ends.)


You will find that the photo album is not that big at all.

You will notice that you have to look past many, many very straight columns with squared-off ends just to find one or two.




It is within this context that the inability to study the actual initiation failure mode by collecting representative columns samples from those areas is shown to be nonsense.

4 core samples collected?

You folks have a deep-seated faith.

I've been surprised to discover how little you actually have by way of evidence.


I believed you had more.


Your defense of such a scant collection of core columns tells the honest reader that you have nothing but a belief system:


Buildings fell, therefore core columns buckled.

No problem. I just think a new thread would help focus on the failure mode which is an important issue in itself. I can start it and see if anyone follows.

 

[Norseman]

No core box columns recovered from the collapse initiation zones.

38 foot giant rectangular things. Where did they go?

There were no box columns in the collapse initiation zone of WTC 1 on floor 98. All were rolled wide flange columns.

In the initiation zone of WTC 2 on floor 81/82 there was only 17 box column out of 47. And they were square and nothing like the size of the big square ones lower in the tower.

See Figure 2-6 in NIST NCSTAR 1-3 for floor of transition from box column to rolled wide flange column.

This column was recovered from the collapse initiation zone of WTC 2:

See NIST NCSTAR 1-3B and 1-3C for further details.

But I guess that you are going to deny that this one is genuine to since it was photographed in a parking lot and not in the debris pile.

How do you think it failed?

 

[Major_Tom]

Thanks for showing some model, NB.


We'll look into this to see if this matches what was observed.



Gregory, good idea.

 

[SDC]

Major Tom, the reasons why the columns failed in buckling but no large deformities are present in the columns is based on simple engineering principles.

[URL]http://www.internationalskeptics.com/forums/imagehosting/thum_16329479baa90cc44e.jpg[/URL]

Just do the math. Figure out what bending moments are on the column splice when the column is still elastic. When you figure that out, you'll know why.

NB, you must have noticed that MT doesn't do math. He looks at pictures. Not a bad practice in and of itself, but no substitute for serious work.

This thread is just insane. Heiwa and MT and all... they are clueless. They will probably spend the rest of their lives maintaining their unsupportable positions, regardless of common sense, observation, and the work of actual engineers. What madness.

 

[Major_Tom]

Norseman, thanks for the photo. Strong weld, no?


.

 

[Norseman]

Norseman, thanks for the photo. Strong weld, no?

Or could it be that the upper portion of that column was weakened by heat due to fire. And that it still had support from the channel that connected it to the floor trusses on floor 81. So when the upper block started to tilt, when the columns on the east side of that floor failed, it therefore buckled above floor 81 when it became overloaded, and broke off from the upper block like all the columns on that level, allowing the upper block of WTC 2 to fall down inside the lower block, where it ripped off the floor connections on its way down.

Therefore this column is expected to look differently than majority of the column sections in the collapse that broke at their bolt connections or weld connections as expected. But that would not prevent those columns from being bent in the collapse before their connections broke. Or after.

 

[GregoryUrich]

Major Tom, the reasons why the columns failed in buckling but no large deformities are present in the columns is based on simple engineering principles.

[qimg]http://www.internationalskeptics.com/forums/imagehosting/thum_16329479baa90cc44e.jpg[/qimg]

Just do the math. Figure out what bending moments are on the column splice when the column is still elastic. When you figure that out, you'll know why.

Not to make things complicated, but shouldn't the three horizontal members be able to handle some magnitude of eccentricity. Granted the towers had severe eccentricity due to tilting. Not really proper usage of term "eccentricity" but I think you'll get my drift.

 

[beachnut]

I have recalculated Bazant and Zhou's overload ratio with the result that progressive collapse is not predicted by the model. Please see the article:

http://www.cool-places.0catch.com/docs/Overload.pdf

Any constructive comments would be appreciated.

If you provide a model that proves the WTC can not fail due to impact and fire; you will be wrong again. And I think this paper has some real stupid statements in it. But when you get to your own paper, it will be a failure like the rest of 9/11 truth. 6 years and not a single correct conclusion.

Since the WTC did fail due to impact and fire, you have failed in advance.

 

[Newtons Bit]

Not to make things complicated, but shouldn't the three horizontal members be able to handle some magnitude of eccentricity. Granted the towers had severe eccentricity due to tilting. Not really proper usage of term "eccentricity" but I think you'll get my drift.

Draw a moment and shear diagram of the column. Then do it again with the diaphragm disconnected.

I didn't draw that picture to scale, however. Column splices are typically 4feet above finished floor to make it easier on the labor to construct.

 

[Heiwa]

Subject is collapse initiation and WTC1 is easiest to study, i.e. we can see on all videos how the roof drops for 4-5 seconds and there is still no damage at floor 93. In fact it appears that the top part of WTC1 above the initiation zone becomes 15 meters shorter while structure below floor 93 is still intact. And no structure above floor 93 is seen being pushed outwards.

So how can the top part lose 15 meters of its height in a few seconds? Did the walls bucklebend 180° inwards? Where did the floors end up. And what happened to the core? Did it bucklebend 180° utwards still inside the building?

The answers are evidently found by studying the remnants of columns from floor 93-101 of WTC1.

 

[Furcifer]

3bodyproblem notes in fascination:
This info couldn't possibly have been obtained?
???

You changed tenses and therein lies the problem. Perhaps it could have. Perhaps, in a mountain of rubble, the exact pieces you so desire could have been extracted. But they weren't.

Veiled in your question of "How?" is "Why?", and i see no answer to your "How" that will ever change the answer to your actual question of "Why?". Perhaps I'm being too cryptic, I'm not sure.

Anyways, my apologies to Greg and yourself as this is off topic. I mean no disrespect as this is an intelligent conversation and I encourage it to continue.

As to your question (one of them), the welds look nonexistent in the photos. It's interesting and I'll have to learn more.

 

[Major_Tom]

3bodyproblem and all, I believe we are moving that ongoing conversation within this thread to a new thread entitled "failure mode" at Gregory's request.

I'll be moving my part of this exchange over there.

No offence taken. I appreciate the honest discourse.

 

[Heiwa]

If you provide a model that proves the WTC can not fail due to impact and fire; you will be wrong again.

Let's do a model test!

You need:

4 off steel pipes, length 750 mm, dia 20 mm wall thickness 1 mm (each cross area 62.83 mm²). Yield stress 23.5 kgs/mm²
1 off 1000 x 1000 x 5 mm steel plate (weight about 40 kgs)
4 off 1000 x 1500 x 5 mm steel plates (each weight about 60 kgs)
4 off 960 x 4 x 3 mm steel flat bars (spandrels)
4 off plywood sheets 995 x 920 x 5 mm. Make some holes in them to allow air to enter and smoke to escape! One hole can look like as if a model air plane has made it.

You weld the pipes to the corners of the square steel plate and you get a table with four legs. Each leg has slenderness ratio abt. 75. Weld the spandrels between the legs at about half height.
Put table on firm ground, e.g. cement floor.
Then weld the four other plates on the top of this table to form a 'water tank'.
Fix the four plywood sheets between the legs of the table as a skirt.

Decorations: The 'water tank' on the table is the 'upper mass' of WTC1. You can paint it to look like it. The four plywood sheets - the skirt - are the walls of the initiation zone of WTC1. You can paint that too to look like it. It is in fact a 1/20 model of part of WTC1 'mass above' and 'initiation zone'. The legs are four of the columns!

Load on table: In order to compress the table legs in the WTC1 model initiation zone at say 30% yield we need abt 1 500 kgs of weight on the table top! Thus you fill the water tank to level about 1.5 meter and there you are: 1 500 kgs of water + 280 kgs of steel plates = 1 780 kgs are carried by four legs each cross area 63 mm². Stress in columns = 7.06 kgs/mm² = 30% of yield stress.

Table, 0.755, m and tank, 1.5 m, make a 2.255 m high model of WTC1 mass above and initiation zone!

Then you fit a suitable thermometer to record the temperature inside the initiation zone.

The volume of the initiation zone is only 0.75 m3 and it is quite easy to heat it up to 500°C!

Cost of model is not too much: 7 m² of 5 mm steel plate (280 kgs) - say $400:- Pipes $20:-, Skirt $80:- welding rods, paint and misc. $100:- . Labour $ 0:-, if you ask daddy to assemble it.

Now the fun starts! We are going to put this model of WTC1 on fire! Or at least the initiation zone.

Put a tray of one gallon diesel oil on the cement floor between the legs of the model and fill the rest of the initiation zone with paper, rugs and similar.
Now put the diesel oil on fire! See how the initiation zone heats up, air is drawn in and smoke escapes through the holes. Very soon the temperature is 500°C uniformly inside the initiation zone and the table legs are heated up to same temperature. The plywood will burn very slowly.

The purpose of the model test is of course to establish the stiffness of the table leg pipes (the columns of the initiation zone) under heat and to see if suddenly, at, e.g. temperature 500° C, the mass above (luckily most water in this test) drops down, at a significant speed and with an enormous kinetic energy, and impacts on the cement floor with an enormous dynamic load.

Or does nothing of that sort happen? Maybe the table legs will just bulge. You will find out (the latter)!