Merged Applicability of Bazant's model to the real world

[Tony Szamboti]

The highlighted text is incorrect.

The static load is 1mg, where m is the mass of the supported structure. At the static load of 1mg, the acceleration is zero, hence the deceleration is also zero. For a dynamic jolt of three times the static load, the deceleration would be 2g, not 3g: The first 1mg of force offsets the force of gravity and reduces the acceleration to zero but does not change the velocity. The remaining 2mg of the 3mg force is available to reduce the acceleration further (causing the 2g of deceleration).

Tony has made this mistake many times before, and has been corrected by many different people, but appears to have learned nothing from those corrections. It's almost as though Tony is deliberately exaggerating the magnitude of the jolt he expects.

What's more, my correction of Tony's miscalculation does not fix all of the errors he made in that brief statement I quoted above. Tony is misapplying an engineering rule of thumb that suffices for static situations but is grossly inappropriate for the dynamic situation he is pretending to model. For a correct calculation, see pages 308-311 of the Bažant and Verdure (2007) paper I cited earlier in this thread.

As Bažant and Verdure explain, detailed modelling of the force F(u) "is a formidable problem", but the kinetic energy of the falling upper section is easier to estimate, as is the energy dissipation obtained by integrating F(u) over distance. The kinetic energy of the falling section is roughly one decimal order of magnitude larger than the energy needed to initiate the accelerated collapse seen on 11 September 2001.

Tony Szamboti can't be expected to understand that, because he's still comparing impulses and accelerations.

Estimation of F(u) and its integration with respect to distance is complicated by the phenomenon described below by Dave Rogers. First, though, let's pay our respects to the comedy of Tony's argument:

1. It doesn't look like any deliberate demolition Tony has ever seen.
2. Conclusion: It was "unnatural".

In Tony-speak, "unnatural" evidently means collapses that don't look like deliberate demolitions must have been deliberate demolitions.

Someone who hasn't been paying attention might think I'm kidding or giving Tony an unnecessarily hard time. Sadly, no:

Nothing but antics with semantics here as it seems that is all you can really do. The 3g deceleration is from a freefall reference and would include the static load support plus an additional 2g.

You are really reaching for minutia to distort Clinger. What is actually sad is the level of distortion some people on this forum will stoop to to try to maintain a delusion that a ridiculous and fraudalent story could possibly have merit. Face it and deal with the reality that the towers were deliberately demolished along with WTC 7.

 

[beachnut]

Nothing but antics with semantics here as it seems that is all you can really do. The 3g deceleration is from a freefall reference and would include the static load support plus an additional 2g.

You are really reaching for minutia to distort Clinger. What is actually sad is the level of distortion some people on this forum will stoop to to try to maintain a delusion that a ridiculous and fraudalent story could possibly have merit. Face it and deal with the reality that the towers were deliberately demolished along with WTC 7.

Bazant's model proves you have delusions and nonsense. You have delusions and you can't help it. You have no clue about 911, and your real cd deal has failed.

You lost this one, Clinger beat you again! He did a job so good you only spewed talk to defend your delusions. But that is all you have ever done.

 

[ozeco41]

The highlighted text is incorrect.

The static load is 1mg, where m is the mass of the supported structure. At the static load of 1mg, the acceleration is zero, hence the deceleration is also zero. For a dynamic jolt of three times the static load, the deceleration would be 2g, not 3g: The first 1mg of force offsets the force of gravity and reduces the acceleration to zero but does not change the velocity. The remaining 2mg of the 3mg force is available to reduce the acceleration further (causing the 2g of deceleration).

Tony has made this mistake many times before, and has been corrected by many different people, but appears to have learned nothing from those corrections. It's almost as though Tony is deliberately exaggerating the magnitude of the jolt he expects.
....

Thanks for posting that outline of the base physics W.D.

Tony is wrong in two main areas - both fatal to his claims:

• In the base physics related to accelerations, velocities, impulses and where "g" fits into the picture; AND
• In the modelling of what actually happened where he is wrong about the mechanisms of collapse at the immediate point where he looks fo his "jolt" AND in the undefined boundaries of his false premise. He has no defined end point to his "jolt" scenario so even if it was correct it cannot end without disproving his pre-determined outcome. If he ever tries to finish his model of the collapse it will come back and bite him. So he has to keep it vague and ambiguous.

 

[GlennB]

Newton's Third Law explains why, in any collision, the larger and/or stronger and/or denser object or structure is going to affect the smaller one disproportionately, and the smaller one loses. Every time.

Oh really? And what if the "larger" object is composed of many components joined by (say) welds and bolts? How will the massiveness of the lower portion protect a weld or bolt from local breakage by an energetically falling component? How will a plastic hinge in a column be prevented from rupturing? The massiveness of the columns at ground level hundreds of yeards away will protect it?

Anyway, a trivial but easy refutation of your claim -- flip one of the upper cards and the entire structure comes down in a cascading failure as local connections are unable to survive each impact. Bazant addresses this.

 

[ozeco41]

Newton's Third Law explains why, in any collision, the larger and/or stronger and/or denser object or structure is going to affect the smaller one disproportionately, and the smaller one loses. Every time.

Oh really? And what if the "larger" object is composed of many components joined by (say) welds and bolts? How will the massiveness of the lower portion protect a weld or bolt from local breakage by an energetically falling component? How will a plastic hinge in a column be prevented from rupturing? The massiveness of the columns at ground level hundreds of yeards away will protect it?

Anyway, a trivial but easy refutation of your claim -- flip one of the upper cards and the entire structure comes down in a cascading failure as local connections are unable to survive each impact. Bazant addresses this.

[qimg]http://i250.photobucket.com/albums/gg274/sap-guy/houseofcards.jpg[/qimg]

If ergo is right its no use shooting a charging elephant with a rifle.

 

[Dave Rogers]

In real life, in all buildings where a smaller upper block is attempting to descend through a much larger lower block, the lower block wins. If you disagree, please provide an example outside of the one you're trying to claim. Thanks.

Well, there's every Verinage demolition, Bailey's Crossroads, and Ronan Point. Now, let's see your examples of all buildings in real life where a smaller upper block - as a reasonable guideline, let's say 10% of the mass - falls on the remainder of the structure and collapse arrests. Since it happens in "all buildings", you'll have no problems finding an example.

Please apply Newton's Three Laws of Motion to the WTC 1 and 2 collapses. I've never actually seen a da bunker do this.

Yes, you have. You're just incapable of understanding what you see. Every analysis of the collapse uses Newton's Laws implicitly at every stage of the calculation.

Dave

 

[Dave Rogers]

The debris from the upper block? So you are admitting that the upper block is crushing itself up before it can crush anything down?

As usual, nobody is 'admitting' anything. You're claiming that, if the upper block is crushed up, collapse will arrest. This claim requires that the debris from the crushing of the upper block, in your scenario, mysteriously vanishes. In other words, even if you weren't wrong about crush-up, you'd still be wrong about crush-down.

Dave

 

[pgimeno]

Dave, remember you're talking to the most promising candidate for the August Stundie award, for this masterpiece:

I'm not sure even a moon-sized field or mountain of rubble, dropped from a height of 12 feet would entirely crush the WTC. No. If you had it coming down from a higher height, in a steady stream over a long period of time, we would certainly see some major damage. Total collapse? I'm not sure.

 

[GlennB]

Dave, remember you're talking to the most promising candidate for the August Stundie award, for this masterpiece:

I swear he's channelling Heiwa's infamous "3 mile drop" farrago of bilge.

 

[Tony Szamboti]

Well, there's every Verinage demolition, Bailey's Crossroads, and Ronan Point. Now, let's see your examples of all buildings in real life where a smaller upper block - as a reasonable guideline, let's say 10% of the mass - falls on the remainder of the structure and collapse arrests. Since it happens in "all buildings", you'll have no problems finding an example.

Every Verinage demolition has a significant observable deceleration when the upper section meets the lower. I would be willing to bet that if we had video of Ronan's Point and Bailey's Crossroads we would see it there also. It happens in every natural collapse. What you won't be able to produce is an example of a natural collapse where there is no deceleration of the impacting object.

The only reason it wouldn't happen is if the structural integrity below was largely removed prior to the impact. That is the only legitimate explanation for the lack of deceleration of the upper section of WTC 1.

It is amazing that with the above in mind, the freefall acceleration of WTC 7's upper section, evidence of energetic materials in the dust, and the fact that most of the steel was destroyed before it could be analyzed, that some people still actually believe the collapses of the towers and WTC 7 were anything but intentional controlled demolitions with the aircraft nothing but causal ruses.

 

[GlennB]

.... an example of a natural collapse where there is no deceleration of the impacting object.

Given your almost spotless record of imprecision in the use of this word you had better define what you think it means. Every time you use it, in fact, for the avoidance of misunderstanding.

 

[Dave Rogers]

Every Verinage demolition has a significant observable deceleration when the upper section meets the lower. I would be willing to bet that if we had video of Ronan's Point and Bailey's Crossroads we would see it there also. It happens in every natural collapse. What you won't be able to produce is an example of a natural collapse where there is no deceleration of the impacting object.

See, this is why I don't usually bother replying to you any more. You know perfectly well that verinage demolitions are controlled carefully such that the upper block falls directly on the lower, with no rotation. Your speculation about Ronan Point and Bailey's Crossroads is worthless. And I've pointed out to you ad nauseam that the rotation of the upper block, clearly observed in the collapse of WTC1, results in a distributed impact so that no large jolt is observable. Sadly, it's about as worthwhile as talking to my cat.

The only reason it wouldn't happen is if the structural integrity below was largely removed prior to the impact. That is the only legitimate explanation for the lack of deceleration of the upper section of WTC 1.

Yawn.

It is amazing that with the above in mind,

Inability to visualise solid geometry does not constitute a compelling argument.

evidence of energetic materials in the dust,

Incompetent analysis that nevertheless directly refutes the conclusion it seeks to draw does not constitute a compelling argument.

the fact that most of the steel was destroyed before it could be analyzed,

Blatant lying does not constitute a compelling argument.

and the freefall acceleration of WTC 7's upper section,

Mischaracterisation of already understood phenomena does not constitute a compelling argument.

that some people still actually believe the collapses of the towers and WTC 7 were anything but intentional controlled demolitions with the aircraft nothing but causal ruses.

No bangs, hence no explosives. No feasible method, hence no thermite. You don't even have a coherent hypothesis. Come back when you do.

Dave

 

[Tony Szamboti]

See, this is why I don't usually bother replying to you any more. You know perfectly well that verinage demolitions are controlled carefully such that the upper block falls directly on the lower, with no rotation. Your speculation about Ronan Point and Bailey's Crossroads is worthless. And I've pointed out to you ad nauseam that the rotation of the upper block, clearly observed in the collapse of WTC1, results in a distributed impact so that no large jolt is observable. Sadly, it's about as worthwhile as talking to my cat.



Yawn.



Inability to visualise solid geometry does not constitute a compelling argument.



Incompetent analysis that nevertheless directly refutes the conclusion it seeks to draw does not constitute a compelling argument.



Blatant lying does not constitute a compelling argument.



Mischaracterisation of already understood phenomena does not constitute a compelling argument.



No bangs, hence no explosives. No feasible method, hence no thermite. You don't even have a coherent hypothesis. Come back when you do.

Dave

I think most rational people would call your reply here incoherent. You seem to use that word loosely, much like your silly attempts at explaining the lack of deceleration of the upper section of WTC 1 as being possible in a natural collapse.

It is actually a joke that anyone technical who has looked into the technical aspects of Sept. 11, 2001, and is even a little bit aware of politics, can come away with any conclusion other than it was a shock and awe ruse to get the people of the U.S. to support the use of their military for pre-planned illicit oil wars.

On top of the evidence for controlled demolition, there is so much evidence for motive by insiders, with things like the PNAC manifesto, Dick Cheney's secret national energy policy meetings, and the Bush administration's lies about WMD in Iraq etc. that one has to make a concerted effort to ignore it and keep believing it was all fortuitously caused by evil terrorists from an area that these people wanted some control over.

 

[Oystein]

I think most rational people would call your reply here incoherent. You seem to use that word loosely, much like your silly attempts at explaining the lack of deceleration of the upper section of WTC 1 as being possible in a natural collapse.

It is actually a joke that anyone technical who has looked into the technical aspects of Sept. 11, 2001, and is even a little bit aware of politics, can come away with any conclusion other than it was a shock and awe ruse to get the people of the U.S. to support the use of their military for pre-planned illicit oil wars.

On top of the evidence for controlled demolition, there is so much evidence for motive by insiders, with things like the PNAC manifesto, Dick Cheney's secret national energy policy meetings, and the Bush administration's lies about WMD in Iraq etc. that one has to make a concerted effort to ignore it and keep believing it was all fortuitously caused by evil terrorists from an area that these people wanted some control over.

Ah. Politics trumps sound engineering methods.
It was CD because Cheney is eeeevil. Cheney made the jolts disappear so he could invade Iraq.
Ok.

 

[Dave Rogers]

I see Tony's given up on arguing and descended into ranting, the sure sign of having no rational response.

Dave

 

[leftysergeant]

The central problem regarding the absence of a visible jolt may be that we arer thinking of there being an actual fall through an area of zero resistance that would have been arrested on contact with the lower structure. But, given the heat-weaken nature of the steel in the impacted areras, it could be that the top just sort of settled onto the lower columns and progressively popped apart, shedding floor slabs. Look at how the top of the south tower starts to break into two big pieces. It resembles the way that smoke stacks break somewhere in the middle as they fall without additional explosive assistance.

I am thinking of the bottoms of the top columns having not so much fallen onto, but having slid off the tops of the columns below, causing the cores to split apart from the bottom up, at the same time shedding their floor slabs.

 

[twinstead]

Ah. Politics trumps sound engineering methods.
It was CD because Cheney is eeeevil. Cheney made the jolts disappear so he could invade Iraq.
Ok.

They all eventually show their hands in this debate: It's not about evidence or science, it's all about ideology and politics. At least people like Jihad Jane and Childlike Empress are out front with it. People like Tony and Bill and MM like to hide it in so-called scientific discussion.

 

[carlitos]

Seriously, how the **** does being "a little aware of politics" change anything? We are talking about math and physics. What a ridiculous argument.

 

[twinstead]

Seriously, how the **** does being "a little aware of politics" change anything? We are talking about math and physics. What a ridiculous argument.

Some people can't separate science from politics. (or science from religion)

 

[Newtons Bit]

The reason why the verinage demolition has a noticeable impact and the WTC didn't is rather simple. An offset of just a couple of inches causes a dramatic difference between an open-steel shape (such as an HSS in the WTC) and a concrete column. Observe:



As seen, the impact area of the concrete is still most of the original area. The column will probably fail in compression buckling.

The steel impact is about 1% of the original area, however. What does this mean? It means that about 1% of the steel shape from the upper block and 1% of of that from the lower block impact. The entirety of the force must be transmitted through this location. The local areas do not have enough capacity to develop 3mg, as Tony Szamboti likes to claim. Instead the steel will cut through each other. An expression "like a hot knife through butter" might apply here, but I think a demonstration of it is in order:



Apologies to Howard Taylor.