Heiwa's Pizza Box Experiment

[Zipster]

The thing that dawned on me is Heiwa's use of glue. Obviously, what kind of glue he used if very important (though he never specified). If he's using super glue or the equivalent which can have a tensile strength of over a ton for a relatively small area, he is completely skewing the Pizza Tower model.

The stength of the glue would be much stronger than the "scaled down" forces.

 

[Heiwa]

Please answer the question.

Where does Bazant claim that the upper block remained intact?

In his papers! Let's quote from one (2001):

"Introduction and Failure Scenario

In stage 1 (Fig. 1), the conflagration, caused by the aircraft fuel spilled into the structure, causes the steel of the columns to be exposed to sustained temperatures apparently exceeding 800°C. The heating is probably accelerated by a loss of the protective thermal insulation of steel during the initial blast. At such temperatures, structural steel suffers a decrease of yield strength and exhibits significant viscoplastic deformation ~i.e., creep—an increase of deformation under sustained load!. This leads to creep buckling of columns ~Bazˇant and Cedolin 1991, Sec. 9!, which consequently lose their load carrying capacity (stage 2). Once more than half of the columns in the critical floor that is heated most suffer buckling (stage 3), the weight of the upper part of the structure above this floor can no longer be supported, and so the upper part starts falling down onto the lower part below the critical floor, gathering speed until it impacts the lower part. At that moment, the upper part has acquired an enormous kinetic energy and a significant downward velocity. The vertical impact of the mass of the upper part onto the lower part (stage 4) applies enormous vertical dynamic load on the underlying structure, far exceeding its load capacity, even though it is not heated. This causes failure of an underlying multifloor segment of the tower (stage 4), in which the failure of the connections of the floor-carrying trusses to the columns is either accompanied or quickly followed by buckling of the core columns and overall buckling of the framed tube, with the buckles probably spanning the height of many floors (stage 5, at right), and the upper part possibly getting wedged inside an emptied lower part of the framed tube (stage 5, at left). The buckling is initially plastic but quickly leads to fracture in the plastic hinges. The part of building lying beneath is then impacted again by an even larger mass falling with a greater velocity, and the series of impacts and failures then proceeds all the way down (stage 5)."

As you can see the upper part is assumed to consist of one mass (not multiple masses of structural parts) that impacts the lower part.

The impact only causes failure of an underlying multifloor segment of the lower part and there is no damage to the upper part, which is assumed rigid, indestructible. If the upper part was non-rigid you would expect failures in the upper part structure. Compare Newton(s third law.

Then, strangely Bazant suggests that the upper part may be wedged inside the lower part, thus he assumes the upper part is still intact and friction may be at work. How the intact upper part gets inside the lower structure is a mystery! It is physically impossible as the upper part has same size as the lower part.

Regardless - the upper part (one solid mass only) is not wedged but continues to drop, it remains intact, and even more strange - its mass increases!! It seems that the immobile rubble caused by the first impact is glued to the upper part and accelerates with it. It cannot happen in reality.

The figures in the paper shows the upper part intact all the time.

In a later paper (2008) the above is repeated with further explanations why the upper part is assumed rigid and figures, e.g. with the intact upper part resting on a heap of rubble (before crush up), i.e. the upper rigid part remained intact all the time (no extra mass added to it - very confusing) during the global collapse.

All the formulas in the paper (2001) are of course only one-dimensional (1-D) - upper part, one solid, rigid (point?) mass m, accelerating by gravity down only crushing (compressing) everything in its way.

Anyway, the fundamental error of Bazant is that he assumes the upper part to remain intact at impact and later, i.e. being rigid, during global collapse. No such upper part exists in reality. All videos of the two WTC towers' destructions also show that the upper parts are the first to be destroyed ... not dropping on anything below.

On the other hand, if the upper part had really dropped on the lower structure, the upper part structure would have been affected (locally destroyed and movements arrested in all directions).

 

[JimBenArm]

Oh god, please tell me he doesn't work on submarines.

Simple to find out;
Does the number of surfaces for your boat equal the number of dives?
If so, he didn't work on your boat.

 

[WildCat]

As you can see the upper part is assumed to consist of one mass (not multiple masses of structural parts) that impacts the lower part.

Uh, no. Mass is mass whether it's one solid rigid block or an aggregate of many small parts.

You should stick to writing papers for children, adults aren't buying your nonsense.

 

[Dr Adequate]

In his papers! Let's quote from one (2001):

"Introduction and Failure Scenario

In stage 1 (Fig. 1), the conflagration, caused by the aircraft fuel spilled into the structure, causes the steel of the columns to be exposed to sustained temperatures apparently exceeding 800°C. The heating is probably accelerated by a loss of the protective thermal insulation of steel during the initial blast. At such temperatures, structural steel suffers a decrease of yield strength and exhibits significant viscoplastic deformation ~i.e., creep—an increase of deformation under sustained load!. This leads to creep buckling of columns ~Bazˇant and Cedolin 1991, Sec. 9!, which consequently lose their load carrying capacity (stage 2). Once more than half of the columns in the critical floor that is heated most suffer buckling (stage 3), the weight of the upper part of the structure above this floor can no longer be supported, and so the upper part starts falling down onto the lower part below the critical floor, gathering speed until it impacts the lower part. At that moment, the upper part has acquired an enormous kinetic energy and a significant downward velocity. The vertical impact of the mass of the upper part onto the lower part (stage 4) applies enormous vertical dynamic load on the underlying structure, far exceeding its load capacity, even though it is not heated. This causes failure of an underlying multifloor segment of the tower (stage 4), in which the failure of the connections of the floor-carrying trusses to the columns is either accompanied or quickly followed by buckling of the core columns and overall buckling of the framed tube, with the buckles probably spanning the height of many floors (stage 5, at right), and the upper part possibly getting wedged inside an emptied lower part of the framed tube (stage 5, at left). The buckling is initially plastic but quickly leads to fracture in the plastic hinges. The part of building lying beneath is then impacted again by an even larger mass falling with a greater velocity, and the series of impacts and failures then proceeds all the way down (stage 5)."

At no point in this passage does he say the upper block remained intact.

You want to try again?

Please answer the question.

Where does Bazant claim that the upper block remained intact?

 

[Porkpie Hat]

maybe one day you should read his papers, then you can spot the context......

I've read the paper in question but its been 2-3 years.

 

[nicepants]

The Bazant hypothesis is independent of scale, material, structural arrangemets, etc.

Asking again: Where does Bazant claim that his hypothesis is "independent of scale, material and structural 'arrangements'"?

 

[GreyICE]

Well he's stopped posting my comments on his blog (apparently they have to get his woo seal of approval, and mine stopped getting it)
so whatever. The antimatter theory is a LOT more fun than the nuclear theory, I have to say. Antimatter weaponry! Don't try this at home kids.

 

[Jonnyclueless]

I really REALLY need to know what buildings he has worked on. There's no way I want to risk my life in such places.

 

[Heiwa]

Asking again: Where does Bazant claim that his hypothesis is "independent of scale, material and structural 'arrangements'"?

All mathematical formulas and relationships by Bazant are evidently indepedent of scale (size), material and structural arrangement, etc. Bazant then just uses WTC1 as an example (sic) to show why WTC1,2 collapse when their top parts get loose.

Evidently the same would happen to other structures when their top parts get loose, e.g. the Pizza Tower.

Of course there are many errors in the Bazant paper apart from the assumption that the top part is indestructible. The mass of WTC1 top is assumed to be 58 000 tons, when it is much less. Regardless - that mass (plenty of different parts/masses of all types) is evidently not indestructible. There was a big hole in the structure just below the upper part. Floors were hanging on columns just held by small bolts in the upper part. The columns which carried all the gravity loads and were subject to the alleged impact occupied only 0.14% of the cross section area of the building A (see formula (2) in Bazant's paper.

For our purpose, we may assume that all the impact forces go into the columns and are distributed among them equally. - Bazant

According Bazant the total cross section area A of the building is apparently important but it was 99.86% air (!) in the impact area. How that air could initiate a global collapse is ????

It would appear that the columns occupied only say 5.5 m² of the say 4 000 m² total cross area A of the building. The floors of the upper part evidently do not participate in the 'impact' except with their masses - they are hanging loose above the 'impact location' and put load on the upper part columns. Only upper part columns impact lower structure columns according Bazant. And according Bazant that impact upper part columns against lower structure columns shakes loose the uppermost floor of the lower structure, so that the columns in the lower structure, that that floors was attached to, fail (like spaghetti).

When these top columns of the lower structure have failed, then the upper part repeats the performance with the next floor of the lower structure - all the way to the ground.

The upper part, with its 15 floors hanging on the columns, remain intact all the time according Bazant (and lands on top of the rubble at end of global collapse of the lower structure).

Another funny property, apart from total cross section area A used by Bazant in his equation (2) is the 'specific mass of building per unit volume'. You really wonder what that is?

Equation (2) is however just an estimate of an overload ratio that "is calculated from the elastic wave equation which yields the intensity of the step front of the downward pressure wave caused by the impact if the velocity of the upper part at the moment of impact on the critical floor is considered as the boundary condition" according Bazant.

Not very clear actually, but the 'velocity of the upper part at moment of impact on the critical floor' is another factor (and maybe it was not correctly scaled in the Pizza Tower experiment?).

But - impact on the critical floor?? Previous we are told only columns impact columns and shake the critical floor loose. Maybe Bazant means the velocity of the upper columns impacting the lower columns??

This velocity was very low in WTC 1 (and can be adjusted to be the same with the Pizza Tower experiment)! Say it was 3-4 m/s after a free fall drop of 3.7 m of WTC1 upper part! I am regularly diving from a 5 m board and I can assure you it is quite fun and not dangerous to drop from 5 m (into water though).

It is very easy to check full scale if 260+ WTC 1 tower structure columns collapse, if you drop an upper part on them from 3.7 m height above it. You just need to check one column! Easy for NIST to do!

Each WTC1 column has average cross area say 5.5/260 = 0.0212 m² or 212 cm². Quite solid - abt. 15 x 15 cms solid, square column. In reality it is a box shaped column, say 50 x 50 cms with 1.1 cm thickness (220 cm²).

The weight that impacts it is average 33000/260 = 127 tons or 127000 kgs. The original compressive stress in the column was then 600 kgs/cm² or 25% of yield. This is typical of WTC1. The column could easily carry that!

OK, a new experiment! Drop 127 tons from 3.7 m on the square or box shaped column with cross area 212 cm² supported by ground. It is like a big hammer hitting a small nail!

What happens? Does the column break/collapse or is pushed into the ground? Maybe!

BUT - what about the 127 tons hammer? Does it remain intact? This hammer (upper part) was just another column with cross area 212 cm² and with 127 tons weight added to it (floors bolted to it).

According Bazant the upper part (the hammer) remains intact, applies a force F on the square column and the square column below shakes the ground.

According Newton the square column apply a force -F on the upper part ... and that force will according basic physics shear off all small weights hanging on it = the upper part is destroyed at impact = is not rigid. All the weights of the upper part break loose ... and drop somewhere.

Fascinating stuff, basic physics.

This Bazant paper is really awful.

 

[X]

According Bazant the total cross section area A of the building is apparently important but it was 99.86% air (!) in the impact area.

Except where the floor is. Or is the floor also 99.86% air?

I also wonder if you know where I'm going with this...

 

[Myriad]

All mathematical formulas and relationships by Bazant are evidently indepedent of scale (size), material and structural arrangement, etc.

You can keep asserting this, but anybody can look the formulas in Bazant's papers and see the terms for height and for displacement during the collapse. The values of these terms and the effects of those values on the results of the calculations are dependent on scale in the most direct way possible.

Until you correct this obvious error in your reasoning, there's no reason for anyone to pay the slightest attention to your subsequent explanations and thought experiments.

Respectfully,
Myriad

 

[Zipster]

Please use units when you do your oddball calculations. It's hard to figure out what you're dividing into what to get your resultant units.

I don't know what they did back then, but when I went through college, not having units in your work for an engineering class did not go well with the professors.

5.5 what / 260 what = 0.0212 m²

33000 what / 260 what = 127 tons (I'll assume you mean metric tons)

For all we know, you could just be pulling numbers out of your ass and manipulating them in your favor just to make your argument seem reasonable.

According Bazant the upper part (the hammer) remains intact, applies a force F on the square column and the square column below shakes the ground.

Have you ever hit a nail with a hammer? Not only does it shake the ground, you can also bend the nail if it's secured into something. And not only that, the hammer remains intact does it not?

 

[WilliamSeger]

Actually, Dr. Bazant does divide the collapse into a "crush down" phase and a "crush up" phase (as does Dr. Greening). I originally thought this was just a convenience to simplify the analysis; my "common sense" said the top and bottom sections should have destroyed each other more or less equally. But in Bazant's 2007 and 2008 papers, he has a detailed discussion and quantitative analysis of the phenomenon:

http://www.civil.northwestern.edu/people/bazant/PDFs/Papers/466.pdf
http://www.cs.purdue.edu/homes/cmh/distribution/PapersChron/WTC_I%20Engineering%20Perspective.pdf

The reason is that the collapsing building did not consist of just the top and bottom sections, but also a third part: the accumulating layer of debris, which was also falling. It was actually this debris, not the top section, that was directly impacting the lower structure and absorbing a lot of the reactive dynamic force, so it limited (but did not completely eliminate) the amount of damage that could be done to the top section in the collisions -- as long as the impacted floors gave way. However, when the debris layer reached the ground, it could go no farther and whatever remained of the top section was destroyed in the "crush up" phase.

Heiwa (and others) would have us believe that the "crush down/crush up" model demonstrates that Bazant doesn't know what he's talking about. Properly understood, it appears to demonstrate the exact opposite.

 

[Mr.D]

The weight that impacts it is average 33000/260 = 127 tons or 127000 kgs. The original compressive stress in the column was then 600 kgs/cm² or 25% of yield. This is typical of WTC1. The column could easily carry that!

Oh there we go again, confusing static and dynamic.

Pesky things, those moving objects.

 

[tanabear]

At no point in this passage does he say the upper block remained intact.

You want to try again?

Please answer the question.

Where does Bazant claim that the upper block remained intact?

"The gravity-driven progressive collapse of a tower consists of two phases—the crush-down, followed by crush-up each of which is governed by a different differential equation. During the crush-down, the falling upper part of tower having a compacted layer of debris at its bottom is crushing the lower part...with negligible damage to itself. During the crush-up, the moving upper part C of tower is being crushed at bottom by the compacted debris B resting on the ground.

The fact that the crush-up of entire stories cannot occur simultaneously with the crush-down is demonstrated by the condition of dynamic equilibrium of compacted layer B, along with an estimate of the inertia force of this layer due to vertical deceleration or acceleration

...the hypothesis that the crush-down and crush-up cannot occur simultaneously is almost exact."

"What Did and Did not Cause Collapse of WTC Twin Towers in New York"
Zdenek P. Bazant, Jia-Liang Le, Frank R. Greening and David B. Benson

So Bazant has the upper block crushing the lower block(Crush-down). Then once this upper block finishes crushing the lower block it hits the rubble pile and is destroyed via a crush-up. Yes, I know it is complete nonsense, but this is the best nonsense the defenders of the official 9/11 fairy tale can come up with.

 

[X]

"The gravity-driven progressive collapse of a tower consists of two phases—the crush-down, followed by crush-up each of which is governed by a different differential equation. During the crush-down, the falling upper part of tower having a compacted layer of debris at its bottom is crushing the lower part...with negligible damage to itself. During the crush-up, the moving upper part C of tower is being crushed at bottom by the compacted debris B resting on the ground.

The fact that the crush-up of entire stories cannot occur simultaneously with the crush-down is demonstrated by the condition of dynamic equilibrium of compacted layer B, along with an estimate of the inertia force of this layer due to vertical deceleration or acceleration

...the hypothesis that the crush-down and crush-up cannot occur simultaneously is almost exact."

"What Did and Did not Cause Collapse of WTC Twin Towers in New York"
Zdenek P. Bazant, Jia-Liang Le, Frank R. Greening and David B. Benson

So Bazant has the upper block crushing the lower block(Crush-down). Then once this upper block finishes crushing the lower block it hits the rubble pile and is destroyed via a crush-up. Yes, I know it is complete nonsense, but this is the best nonsense the defenders of the official 9/11 fairy tale can come up with.

Very good.

Now: What kind of effect do you think a layer of compacted debris at the bottom of the upper layer will have when the upper layer impacts a floor of the lower layer?

Try looking at it this way: What happens when you catch a hardball bare-handed? What happens when you catch it with some hard leather (i.e. a baseball glove) between you and the ball?

 

[pomeroo]

All mathematical formulas and relationships by Bazant are evidently indepedent of scale (size), material and structural arrangement, etc. Bazant then just uses WTC1 as an example (sic) to show why WTC1,2 collapse when their top parts get loose.

Evidently the same would happen to other structures when their top parts get loose, e.g. the Pizza Tower.

Of course there are many errors in the Bazant paper apart from the assumption that the top part is indestructible. The mass of WTC1 top is assumed to be 58 000 tons, when it is much less. Regardless - that mass (plenty of different parts/masses of all types) is evidently not indestructible. There was a big hole in the structure just below the upper part. Floors were hanging on columns just held by small bolts in the upper part. The columns which carried all the gravity loads and were subject to the alleged impact occupied only 0.14% of the cross section area of the building A (see formula (2) in Bazant's paper.

For our purpose, we may assume that all the impact forces go into the columns and are distributed among them equally. - Bazant

According Bazant the total cross section area A of the building is apparently important but it was 99.86% air (!) in the impact area. How that air could initiate a global collapse is ????

It would appear that the columns occupied only say 5.5 m² of the say 4 000 m² total cross area A of the building. The floors of the upper part evidently do not participate in the 'impact' except with their masses - they are hanging loose above the 'impact location' and put load on the upper part columns. Only upper part columns impact lower structure columns according Bazant. And according Bazant that impact upper part columns against lower structure columns shakes loose the uppermost floor of the lower structure, so that the columns in the lower structure, that that floors was attached to, fail (like spaghetti).

When these top columns of the lower structure have failed, then the upper part repeats the performance with the next floor of the lower structure - all the way to the ground.

The upper part, with its 15 floors hanging on the columns, remain intact all the time according Bazant (and lands on top of the rubble at end of global collapse of the lower structure).

Another funny property, apart from total cross section area A used by Bazant in his equation (2) is the 'specific mass of building per unit volume'. You really wonder what that is?

Equation (2) is however just an estimate of an overload ratio that "is calculated from the elastic wave equation which yields the intensity of the step front of the downward pressure wave caused by the impact if the velocity of the upper part at the moment of impact on the critical floor is considered as the boundary condition" according Bazant.

Not very clear actually, but the 'velocity of the upper part at moment of impact on the critical floor' is another factor (and maybe it was not correctly scaled in the Pizza Tower experiment?).

But - impact on the critical floor?? Previous we are told only columns impact columns and shake the critical floor loose. Maybe Bazant means the velocity of the upper columns impacting the lower columns??

This velocity was very low in WTC 1 (and can be adjusted to be the same with the Pizza Tower experiment)! Say it was 3-4 m/s after a free fall drop of 3.7 m of WTC1 upper part! I am regularly diving from a 5 m board and I can assure you it is quite fun and not dangerous to drop from 5 m (into water though).

It is very easy to check full scale if 260+ WTC 1 tower structure columns collapse, if you drop an upper part on them from 3.7 m height above it. You just need to check one column! Easy for NIST to do!

Each WTC1 column has average cross area say 5.5/260 = 0.0212 m² or 212 cm². Quite solid - abt. 15 x 15 cms solid, square column. In reality it is a box shaped column, say 50 x 50 cms with 1.1 cm thickness (220 cm²).

The weight that impacts it is average 33000/260 = 127 tons or 127000 kgs. The original compressive stress in the column was then 600 kgs/cm² or 25% of yield. This is typical of WTC1. The column could easily carry that!

OK, a new experiment! Drop 127 tons from 3.7 m on the square or box shaped column with cross area 212 cm² supported by ground. It is like a big hammer hitting a small nail!

What happens? Does the column break/collapse or is pushed into the ground? Maybe!

BUT - what about the 127 tons hammer? Does it remain intact? This hammer (upper part) was just another column with cross area 212 cm² and with 127 tons weight added to it (floors bolted to it).

According Bazant the upper part (the hammer) remains intact, applies a force F on the square column and the square column below shakes the ground.

According Newton the square column apply a force -F on the upper part ... and that force will according basic physics shear off all small weights hanging on it = the upper part is destroyed at impact = is not rigid. All the weights of the upper part break loose ... and drop somewhere.

Fascinating stuff, basic physics.

This Bazant paper is really awful.

Speaking of basic physics, you have stated that dropping the top third of a building from a great height onto the bottom two-thirds does no damage. You are ludicrously wrong. You have never backed off your fantastic blunder. Will you do so now?

 

[pomeroo]

"The gravity-driven progressive collapse of a tower consists of two phases—the crush-down, followed by crush-up each of which is governed by a different differential equation. During the crush-down, the falling upper part of tower having a compacted layer of debris at its bottom is crushing the lower part...with negligible damage to itself. During the crush-up, the moving upper part C of tower is being crushed at bottom by the compacted debris B resting on the ground.

The fact that the crush-up of entire stories cannot occur simultaneously with the crush-down is demonstrated by the condition of dynamic equilibrium of compacted layer B, along with an estimate of the inertia force of this layer due to vertical deceleration or acceleration

...the hypothesis that the crush-down and crush-up cannot occur simultaneously is almost exact."

"What Did and Did not Cause Collapse of WTC Twin Towers in New York"
Zdenek P. Bazant, Jia-Liang Le, Frank R. Greening and David B. Benson

So Bazant has the upper block crushing the lower block(Crush-down). Then once this upper block finishes crushing the lower block it hits the rubble pile and is destroyed via a crush-up. Yes, I know it is complete nonsense, but this is the best nonsense the defenders of the official 9/11 fairy tale can come up with.

You know that serious researchers are wrong, but you know nothing about physics or engineering. Here's a question your fellow liars always duck, and you will not be the exception: What do you know that real experts don't, and how did you learn it?

 

[GreyICE]

I love how truthers can parse a simple sentence, arrive at the absolute most absurd interpretation of the words possible, then strawman that interpretation.

It beggars belief.