Is there a legitimate reason to question the official narrative*?

[Tony Szamboti]

Agreed the free fall was a wrong assumption, however the core strength does not appear to be, because the mechanism of failure was weld failure.
It took 1,000,000,000 Ft. Lbs to sheer one weld in a direct strike, now that sounds like a lot, however with an off center strike it takes 100,000 Ft. Lbs, so the way the vector of the work
Is applied greatly affects the energy values needed to accomplish the work.

I would agree with your contention of weld failure and lower energies of absorption involved due to vectoring after several stories have collapsed, but not before.

My interest is in what should happen in these first several stories where there was little to no tilt of the North Tower's upper section.

Initially, there would be column buckling in a natural collapse. Up until recently Bazant's analysis was accepted without question. It has been shown to be without merit and due to his intransigence on the subject should now be looked at with disdain.

 

[Jango]

Smaller parts were laboriously put over conveyor belts at Fresh KIlls and inspected by hand by teams of people. Material was retrieved down to the level of door keys.

If you really expect thousands of photos then, I'm afraid, the level of physical evidence you require can never be met.

Meanwhile your highlighted statement above isn't strictly true, is it? Here you've limited it to physical remains. People also responded by pointing out that CD would inevitably require flashes and bangs that did not happen. There is overwhelming evidence of no CD.

For a reason, mind you. The flashes and bangs could have been obscured by the overall chaotic scene when the building began to collapse, as explosions were heard (what those explosions were is a matter of a guessing game) by the police and firemen. The paydirt is physical evidence.

 

[Dave Rogers]

Bazant's overestimate of kinetic energy is nearly 4 times what it actually is, since he doubles the component from velocity and nearly doubles the component from mass.

Nearly double mass, accepted. Nearly double velocity doesn't add up. Working this out from an energy point of view, which is equally valid, and using your own argument, we assume that immediately prior to collapse initiation the resistance of the columns was equal to the weight of the upper block; from your references the average resistance during collapse is about 30-40% of the resistance of the static structure; and energy released is net force times distance. Net force is 0.6-0.7g (gravitational force minus structural resistance), distance is unchanged, therefore kinetic energy is only reduced by the structural resistance. Multiplying the two together we get a KE of 30-35% of Bazant's value. Simple physics based on your own arguments.

Dave

 

[Dave Rogers]

The flashes and bangs could have been obscured by the overall chaotic scene when the building began to collapse, as explosions were heard (what those explosions were is a matter of a guessing game) by the police and firemen.

Timings of those explosions is rather important, though. The explosions initiating the collapse would have to take place before the collapse, and therefore couldn't have been hidden by the sound of the collapse because it hadn't started. Video sound tracks from the day simply don't contain those sounds (except in a couple of cases where they've been edited in, which isn't that hard and can be detected).

Dave

 

[Tony Szamboti]

Nearly double mass, accepted. Nearly double velocity doesn't add up. Working this out from an energy point of view, which is equally valid, and using your own argument, we assume that immediately prior to collapse initiation the resistance of the columns was equal to the weight of the upper block; from your references the average resistance during collapse is about 30-40% of the resistance of the static structure; and energy released is net force times distance. Net force is 0.6-0.7g (gravitational force minus structural resistance), distance is unchanged, therefore kinetic energy is only reduced by the structural resistance. Multiplying the two together we get a KE of 30-35% of Bazant's value. Simple physics based on your own arguments.

Dave

Bazant's free fall had a velocity of 8.5 m/s after a one story fall and the actual measurement shows 6.1 m/s. Since the velocity component in kinetic energy is a function of it being squared (8.5^2 = 72.25 and 6.1^2 = 37.21) you can now see how it doubles the velocity component.

You are also forgetting the factor of safety in the columns, which was at least 3 times the static weight of the upper block. The average resistance would be 30-40% x factor of safety x static weight.

Your calculation is thus off by 3X and if you do it properly you too will see that Bazant's overload is fictitious.

 

[ozeco41]

Bazant's free fall had a velocity of 8.5 m/s after a one story fall and the actual measurement shows 6.1 m/s. Since the velocity component in kinetic energy is a function of it being squared (8.5^2 = 72.25 and 6.1^2 = 37.21) you can now see how it doubles the velocity component.

You are also forgetting the factor of safety in the columns, which was at least 3 times the static weight of the upper block. The average resistance would be 30-40% x factor of safety x static weight.

Your calculation is thus off by 3X and if you do it properly you too will see that Bazant's overload is fictitious.

Generally agreed BUT only because it is an abstract model.

Even for an abstract model the 'average' assumption - which in part means uniformly falling/impacting across the floor plan - is very optimistic. reality almost certainly would see some parts getting ahead and others lagging behind. Producing load concentrations and breaking the "average" concept.

So similar to the tilt we saw in the real event. And once it goes unequal distribution then the "average" goes out the window and the effective resistance becomes far less (or the falling load effectively more) because it would force concentrated overloading of the "first bits to get hit"

So the question within the constraints of an abstract model is "is such an unrealistic model good enough for some abstract purpose such as a limit case argument?"

And the effects I have described are all Bazant's way. They favour his "limit case" conclusion.

And - "No - I will not quantify it"

but the qualified reasoning shows it doesn't harm Bazantian reasoning - it is still conservative even if at this stage I cannot say by how much.

 

[GlennB]

For a reason, mind you. The flashes and bangs could have been obscured by the overall chaotic scene when the building began to collapse, as explosions were heard (what those explosions were is a matter of a guessing game) by the police and firemen. The paydirt is physical evidence.

The flashes and bangs precede CD collapse, though sometimes continue as collapse commences. There are 000's of videos out there of commercial CDs - knock yourself out. Those few explosions that were reported on 9/11 were not associated with collapse, as has been pointed out before.

But your 'paydirt' can never happen, either as clear proof or clear disproof. The nearest we might get would be good evidence of unspent detcord in the debris, just for example. There's zero evidence of any physical signs of CD, either materially or through observation.

Why harp on about it?

 

[Dave Rogers]

You are also forgetting the factor of safety in the columns, which was at least 3 times the static weight of the upper block. The average resistance would be 30-40% x factor of safety x static weight.

Not according to your paper, in which you stated that the resistance of the support structure at collapse initiation must be equal to the weight of the upper block. You're arguing with yourself here.

Dave

 

[Crazy Chainsaw]

Generally agreed BUT only because it is an abstract model.

Even for an abstract model the 'average' assumption - which in part means uniformly falling/impacting across the floor plan - is very optimistic. reality almost certainly would see some parts getting ahead and others lagging behind. Producing load concentrations and breaking the "average" concept.

So similar to the tilt we saw in the real event. And once it goes unequal distribution then the "average" goes out the window and the effective resistance becomes far less (or the falling load effectively more) because it would force concentrated overloading of the "first bits to get hit"

So the question within the constraints of an abstract model is "is such an unrealistic model good enough for some abstract purpose such as a limit case argument?"

And the effects I have described are all Bazant's way. They favour his "limit case" conclusion.

And - "No - I will not quantify it"

but the qualified reasoning shows it doesn't harm Bazantian reasoning - it is still conservative even if at this stage I cannot say by how much.

Tony's argument seems to be on the original Bazant
Paper, not the revised paper by Dr. Frank Greening, and Dr David Benson.

The energy values and resistance to collapse are different between the two.
the original Bazant paper is pre NIST, the information provided by Thomas Edgars,
Who first proposed thermite reactions and burning Aluminum and bowing of trusses caused a pancake collapse of the towers, all of which was wrong.

The Greening-Benson paper is post NIST, Identifies weld failure and connection failure as the
Main failure mode that lead to rapid collapse with revised values.

It is important that confusion not exist between the papers.

Leverage in the core seems to have fractured some of the welds on the core column below
the impact zone . This was an elastic process that transitioned into brittle weld failure,
Based on evidence of the pictures provided of the steel where buckling occurred.

That is also what the New York investigation 2001 pointed too.

 

[ozeco41]

Not according to your paper, in which you stated that the resistance of the support structure at collapse initiation must be equal to the weight of the upper block. You're arguing with yourself here.

Dave

That should teach me to not post late at night after a heavy day.
My focus was on the impracticality of "average" and reality of load concentration in a real event are still valid - whatever the ABSOLUTE value.

 

[Tony Szamboti]

Not according to your paper, in which you stated that the resistance of the support structure at collapse initiation must be equal to the weight of the upper block. You're arguing with yourself here.

Dave

No, it is the columns below the initiation that we are discussing afterwards that I say you need the factor of safety involved in.

You can't presuppose the same effect that the initiation site has exists everywhere. You are trying to weasel things here Dave.

 

[ozeco41]

Tony's argument seems to be on the original Bazant
Paper, not the revised paper by Dr. Frank Greening, and Dr David Benson.

Can you give us a proper refernce to that paper. The only one which has been in discussion is "What Did and Did Not Cause Collapse of WTC Twin Towers in New York" by Bazant, Le, Greening and Benson. ["BLGB"]

There are serious problems with that paper if that is the one. Whether taken as an abstract model - which it is - or as reflecting the real event - which it purports to do and gets wrong in the way it does it.

So if there is another more relevant paper by Greening and Benson could you provide a link.

Then I note your repeated references to claims of weld and connection critical failure. you are not explicit as to what stage of collapse. If you refer to the global progression stage THEN are you discussing the columns in line crushing abstract model of B&Z and BLGB OR the real event progression which did not happen the way that either of those papers describes.

I do not see how weld and connection failure could be a significant factor in the columns crushing abstract models. Sure those were what failed in the real event. BUT the only papers I am aware of do not validly discuss the real event.

Please clarify.

 

[Dave Rogers]

No, it is the columns below the initiation that we are discussing afterwards that I say you need the factor of safety involved in.

No, it wasn't. You talked about average resistance, not energy absorption capacity. Again, everyone can read.

Dave

 

[ozeco41]

No, it is the columns below the initiation that we are discussing...

Thanks for the clarification.

So it is the columns that the Bazant limit case model assumed were crushed.

And NOT those same columns in the real event where they were bypassed?

AND the discussion is about the abstract model - NOT what really happened?

 

[Tony Szamboti]

No, it wasn't. You talked about average resistance, not energy absorption capacity. Again, everyone can read.

Dave

You want to assume the columns below only had a yield strength equivalent to the static load. That is nonsense and if you don't know it you don't belong in the conversation.

 

[Tony Szamboti]

Thanks for the clarification.

So it is the columns that the Bazant limit case model assumed were crushed.

And NOT those same columns in the real event where they were bypassed?

AND the discussion is about the abstract model - NOT what really happened?

The columns below could not be bypassed, that is an enormous leap without a basis, as there is no mechanism to shift the upper section laterally and inertia will cause it to fall in place.

 

[Crazy Chainsaw]

Can you give us a proper refernce to that paper. The only one which has been in discussion is "What Did and Did Not Cause Collapse of WTC Twin Towers in New York" by Bazant, Le, Greening and Benson. ["BLGB"]

There are serious problems with that paper if that is the one. Whether taken as an abstract model - which it is - or as reflecting the real event - which it purports to do and gets wrong in the way it does it.

So if there is another more relevant paper by Greening and Benson could you provide a link.

Then I note your repeated references to claims of weld and connection critical failure. you are not explicit as to what stage of collapse. If you refer to the global progression stage THEN are you discussing the columns in line crushing abstract model of B&Z and BLGB OR the real event progression which did not happen the way that either of those papers describes.

I do not see how weld and connection failure could be a significant factor in the columns crushing abstract models. Sure those were what failed in the real event. BUT the only papers I am aware of do not validly discuss the real event.

Please clarify.

There are three Bazant papers, the original Bazant paper, the Bazant Greening
Paper, The Bazant, Greening, Benson paper truthers try to use confusion
Between the three to try prove natural collapses is not possible.

The Bazant, Greening, Benson, paper what did and did not cause it, utilizes weld and connection failure
Based on a modification of the Maxwel equation to establish a fracture
Mechanics similar to what you proposed.

Truthers will mix and match the three papers to preach to try the faithful, you have to be
Careful not to fall for that.

The sole purpose of the Greening, Benson, paper was to show that cutting the core columns
With thermite was not nessisary to induce collapses, since explosive charges had been
Debunked early on.

By the absolute lack of evidence for explosives.

 

[Tony Szamboti]

I have shown in this thread that the NIST inward bowing minutes before is fictitious, as it has no mechanism.

I have also shown that Bazant's overload values are enormously overestimated and fictitious, to the point where there is actually no overload at all and very likely an energy deficit.

Thus it is shown that the story we have been formally given as to how the collapse of the North Tower was initiated and vertically propagated is fictitious. Now some here will huff and puff and moan and groan about it, simply because they don't want to believe the reality that this story is pure fiction.

 

[Crazy Chainsaw]

Thanks for the clarification.

So it is the columns that the Bazant limit case model assumed were crushed.

And NOT those same columns in the real event where they were bypassed?

AND the discussion is about the abstract model - NOT what really happened?

The columns were not crushed they were leveraged until they failed,
that was clear from the buckling and weld failure then heating in the
Core was not symmetrical, causing a leveraged effect as I remember.

 

[Tony Szamboti]

There are three Bazant papers, the original Bazant paper, the Bazant Greening
Paper, The Bazant, Greening, Benson paper truthers try to use confusion
Between the three to try prove natural collapses is not possible.

The Bazant, Greening, Benson, paper what did and did not cause it, utilizes weld and connection failure
Based on a modification of the Maxwel equation to establish a fracture
Mechanics similar to what you proposed.

Truthers will mix and match the three papers to preach to try the faithful, you have to be
Careful not to fall for that.

The sole purpose of the Greening, Benson, paper was to show that cutting the core columns
With thermite was not nessisary to induce collapses, since explosive charges had been
Debunked early on.

By the absolute lack of evidence for explosives.

There were actually four papers by Bazant and others concerning the WTC collapses and the overestimate of kinetic energy and underestimate of column energy absorption capacity is found in all four of them.