Why a one-way Crush down is not possible

[bill smith]

He mentions core twice. But he is trapped. Cannot reach the emergency escape stairwells 'in the core' or believes there is no real danger so he stays where he is.
The plane impact/explosion does not seem to have caused a lot of motion on floor 86.
Why doesn't he say - I and the other person cannot take the stairs down, &c. Why does he mention core?

After I had been studying 9/11 for a few months I was struck by the regular pointers that kept cropping up that indicated a conspiracy. Keystone-Cop style clues even. I started a file called 'big fat clues'. This is a link to a short post i put on another thread about that...
http://www.internationalskeptics.com/forums/showthread.php?p=4636130#post4636130

 

[Dave Rogers]

There have been several people who have shown that due to conservation of momentum alone that natural collapses would have taken much longer than 17 seconds. I would think you would know who they are and where to find their discussions on it.

And yet all I can find is analysis that gives 12-13 seconds. If you're aware of work that disagrees with this, post it. It would take less time than playing stupid games. You claimed 17+ seconds for conservation of momentum alone; you have to back up your claims.

Where can I find your work on this?

I haven't published it, since there were multiple results online giving the same answer. I reproduced the analysis myself to check that it was valid.

Dave

 

[leftysergeant]

Did you see this yesterday Heiwa ? Some of the core columns on the 86th floor in WTC1 were 'blown out' prior to collapse initiation.

No, they weren't.

Is that not absolute proof that something was happening to the core colmns that had noting to do with he plane ?

No. That you think so is absolute proof that you cannot understand the processes involved in the discombobulation of an aircraft full of fuel in an enclosed space.


Now, stop a minute and think as hard as you can without frying a brain synapse.

The core was covered in heavy sheetrock.

That has a tendancy to blow out when you over-pressurize whatever it encloses.

This is real simple, head-slapping-calling-yourself-dumb-for-not-understanding-it fire science.

Your entire post here can be paraphrased "Oooooh! Ooooh! Shiney thing over there."

Stop dersiling the thread when it stasrts to wrap too tighhtly around Heiwa's neck.

 

[bill smith]

No, they weren't.



No. That you think so is absolute proof that you cannot understand the processes involved in the discombobulation of an aircraft full of fuel in an enclosed space.


Now, stop a minute and think as hard as you can without frying a brain synapse.

The core was covered in heavy sheetrock.

That has a tendancy to blow out when you over-pressurize whatever it encloses.

This is real simple, head-slapping-calling-yourself-dumb-for-not-understanding-it fire science.

Your entire post here can be paraphrased "Oooooh! Ooooh! Shiney thing over there."

Stop dersiling the thread when it stasrts to wrap too tighhtly around Heiwa's neck.

You don't mean...?.......that SILLY eyewitness....thinking it was he core when you could have told him it was the sheetrock all along....

 

[leftysergeant]

You don't mean...?.......that SILLY eyewitness....thinking it was he core when you could have told him it was the sheetrock all along....

He said debris was blocking the stairwells.

Had that debris include core columns, that far down, he would not have had time to get on the wireless about it./

 

[Tony Szamboti]

And yet all I can find is analysis that gives 12-13 seconds. If you're aware of work that disagrees with this, post it. It would take less time than playing stupid games. You claimed 17+ seconds for conservation of momentum alone; you have to back up your claims.



I haven't published it, since there were multiple results online giving the same answer. I reproduced the analysis myself to check that it was valid.

Dave

Dave, you apparently did not read the threads right. I was asked by Alienentity what I thought the collapse times were and told him based on the measured fall of the upper block of WTC 1 having an acceleration of 0.7g for 3seconds and assuming that rate of acceleration was consistent for the entire fall it would put the collapse time at approximately 11 seconds. That was all I said on the matter.

It was then Alienentity who brought up the 17 seconds, to which I responded that even that time violates the law of conservation of momentum for a natural collapse.

As for those who have looked at Conservation of Momentum one is Dr. Kenneth Kuttler whose paper you can find here http://www.journalof911studies.com/letters/ProfKuttlerWTC1CollapseTimeCalculations.pdf

 

[phil76]

I think all the truthers' theories about global collapse relies on a huge mistake : the upper part and lower part are taken as "solid objects".

Vertical load is supported by the columns only. If you put this vertical load elsewhere then the only resisting part are floors. I don't know how the WTC's floor were designed, but according to my experience they should not be able to support far more than 400 kg/m² (150 kg/m² for an office floor, 450 kg/m² for a pedestrian bridge). A floor is not designed to support another floor. Here we have several floors and a large plane !

 

[Heiwa]

Collapse time = a million years!

So here we have one explanation that the topic of this thread Why a one-way Crush down is not possible is wrong. This is the answer of NIST (actually Sunder/Gross) to an FAQ why structures one-way crush down ... in seconds:

" ...the structure below the level of collapse initiation offered minimal resistance to the falling building mass at and above the impact zone. The potential energy released by the downward movement of the large building mass far exceeded the capacity of the intact structure below to absorb that energy through energy of deformation.

Since the stories below the level of collapse initiation provided little resistance to the tremendous energy released by the falling building mass, the building section above came down essentially in free fall, as seen in
videos. As the stories below sequentially failed, the falling mass increased, further increasing the demand onthe floors below, which were unable to arrest the moving mass."

So, first of all, the structure below (i.e. 97 floors of WTC 1 that I call part A) offers minimal resistance!
That is strange as the structure below, part A, had statically carried the structure above for 30+ years with good resistance.

But now the structure above (which I call part C) was dropped on the structure below - part A! Fair enough. What happens? The structure above - part C - has a mass! OK. I agree. And when this mass, part C, drops it can apply energy (or force) on part A, when contact takes place. And this energy is tremendous! Is it?

Now a problem! Part C has not one mass but several small masses = elements of part C - and these parts actually apply energy/force on one another at impact with part A. There are only a minimal amount of elements in part C that applies energy/force on part A at contact. Most elements in part C apply energy/force on one another and has no idea what's going on.

So a question. What happens to part C? If part A offers little resistance, should not part C offer even less resistance?

If that's the case, part C will collapse immediately at contact with part A ... and that's it. Arrest!

But NIST believes otherwise: "the stories below the level of collapse initiation provided little resistance to the tremendous energy released by the falling building mass".

Nothing happens up in the falling building mass part C. Its tremendous energy is only applied on the neighbours below - part A.

BUT, now it is only a few elements of part A that provided resistance! The top stories of part A - say three? Out of 97.

But what about the bottom stories of part C. Can they really apply a force to demolish their cousins below?

No, the three cousins below in part A offered no resistance and the result? 94 tenants further below in part A was hit by part C at near free fall.

This answer by NIST (Sunder/Gross) to an FAQ is so stupid that you wonder how anybody at JREF can take NIST seriously!

My kids audience is always producing LOL when I try to one-way crush anything by a part of itself. They know it is not possible.

So a one-way crush down time of a structure by itself is not really possible to clock. It takes at least a million years.

 

[Dave Rogers]

Even a 17 second time would still not be possible in a natural collapse of the North Tower due to conservation of momentum, so it still presents problems for the current official explanation.

There have been several people who have shown that due to conservation of momentum alone that natural collapses would have taken much longer than 17 seconds.

Dave, you apparently did not read the threads right.

I've quoted all your relevant comments above, so anyone can read them right.

It was then Alienentity who brought up the 17 seconds, to which I responded that even that time violates the law of conservation of momentum for a natural collapse.

So that, plus the other quotes I've included above, add up to you making a claim that (a) conservation of momentum alone requires a collapse time greater than 17 seconds, and (b) several people have shown this.

As for those who have looked at Conservation of Momentum one is Dr. Kenneth Kuttler whose paper you can find here http://www.journalof911studies.com/letters/ProfKuttlerWTC1CollapseTimeCalculations.pdf

I'm familiar with Kuttler's error-riddled analysis, possibly rather more so than you are if you think he gets 17+ seconds from conservation of momentum alone. As you'll see from section 1.4.1, his calculation using only conservation of momentum gives 12.18 seconds. He has to make the assumption, since specifically refuted by Steven Jones, that all the concrete in the towers was pulverised to dust, and the further equally unwarranted assumption that all the concrete was also ejected without contributing potential energy to the collapse, before he can arrive at a physically unrealistic collapse time. (Since his collapse mechanism is physically unrealistic, this is hardly a surprising result.)

Can you suggest some other sources that support your claim that:

There have been several people who have shown that due to conservation of momentum alone that natural collapses would have taken much longer than 17 seconds.

I would accept three, in this instance, as "several", but please note that I'll be checking (again) that they actually say what you claim they say. In the meantime, we can add Kuttler to the list of results that show 12-13 seconds from conservation of momentum only.

Dave

 

[ozeco41]

I think all the truthers' theories about global collapse relies on a huge mistake : the upper part and lower part are taken as "solid objects".

Vertical load is supported by the columns only. If you put this vertical load elsewhere then the only resisting part are floors. I don't know how the WTC's floor were designed, but according to my experience they should not be able to support far more than 400 kg/m² (150 kg/m² for an office floor, 450 kg/m² for a pedestrian bridge). A floor is not designed to support another floor. Here we have several floors and a large plane !

That is the key error that most make. Even some on the "no demolition side".

"They" presume either solid objects contacting OR a form of contact which has velocity impacts yet still manages to have each column contact its other half ANd transfer full strength in axial compression. Well nigh impossible for each column and even more improbable for all the columns.

So Tony Szamboti; Heiwa; David S Chandler all make that error, decline to correct it and avoid rational debate with the engineers who could show the false assumptions. But Greening also makes the same assumption and Bazant appears to.

Reality is the top blocks of WTC 1 & 2 fell inside the outer tube of columns. Missed most if not all of the core columns and landed on the floor. This crude drawing shows one floor joist to outer column and diagrammatically what happened. Whether an integral whole block or eventually broken into components the same weight of top block plus accumulating debris of severed floors landed on the floor joist to column connections.

That connection designed for one floor and its loads asked to take ten floors or more of total structure. So 20 times overload even if statically applied. Add momentum and easily in the 50-100 times overload.

So even with say 5 times safety you still have at least 10 times overload and it takes no engineering degree to say that is "overwhelming" and the joint fails.(FEMA drawing, my add ons are the crude bits)

 

[GlennB]

..... He has to make the assumption, since specifically refuted by Steven Jones, that all the concrete in the towers was pulverised to dust ...

And the link supporting that assumption doesn't work. Why do truthers continue to peddle this "all the concrete was pulverised to dust" nonsense?

 

[bill smith]

He said debris was blocking the stairwells.

Had that debris include core columns, that far down, he would not have had time to get on the wireless about it./

If he had only known it he was giving us conspiracy people something to talk about.

 

[Heiwa]

That is the key error that most make. Even some on the "no demolition side".

"They" presume either solid objects contacting OR a form of contact which has velocity impacts yet still manages to have each column contact its other half ANd transfer full strength in axial compression. Well nigh impossible for each column and even more improbable for all the columns.

So Tony Szamboti; Heiwa; David S Chandler all make that error, decline to correct it and avoid rational debate with the engineers who could show the false assumptions.

Here is another little test:

See the structure left? It consist of horizontal and vertical elements connected to each other. There are 24 levels of horizontal elements all similar supported by 4 rows of vertical elements. The vertical elements supports the horizontal elements.
In structure right we have removed the vertical elements between levels 20/21, so the structure becomes an upper part C and a lower part A.
Let's assume we then drop part C on part A (initiation).
Pls explain how part C can one-way crush down part A after impact/contact and in what order the elements fail, and why.

 

[ozeco41]

If he had only known it he was giving us conspiracy people something to talk about.

Since when did you need help bill?

It isn't all that hard. The basics are:

1) Mustn't fit the evidence; AND

2) Must be totally inconsistent with the last thing claimed.

So "Witness xyz heard the explosions of the thermate and there was residue on rthe dust in 2001 of super thermate which was invented in 2005 and it must have been demolition because it was an inside job....

 

[TexasJack]

Bananaman, please explain to Tony and the rest of us for that matter, what produced this piece of evidence?

[qimg]http://911research.wtc7.net/wtc/evidence/metallurgy/images/WTC_apndxC_img_2.jpg[/qimg]


The evidence is there. FEMA has/had it. NIST ignored it. I emailed them and the email was posted in the public comments section about this steel. If they tested it or what their conclusions were regarding this evidence. They ignored my email like they ignored the evidence, just like you are ignoring the evidence!
Of course for the official collapse theory to stand, a lot of things have to be ignored. After all its the debunker's favorite tactic: Fallacy of Omission. And by omitting the evidence that has presented by Hewia, Tony, Dr. Jones, and many others, you allow yourself to believe the official theory: a pseudo-politico-faith based science more akin to religion than true science.

After doing a simple google search, this school teacher is asking the same question, so maybe he got a response.
http://wtc.nist.gov/comments08/bradReamwtc7comments.pdf

Try asking him, and while your at it, ask him what his scientific question has to do with World Geography.

 

[boloboffin]

After doing a simple google search, this school teacher is asking the same question, so maybe he got a response.
http://wtc.nist.gov/comments08/bradReamwtc7comments.pdf

Try asking him, and while your at it, ask him what his scientific question has to do with World Geography.

Wow, old news. That piece of metal is still at Worcester Polytechnic Institute that has had it since the beginning. One of the scientists with access to it was on the BBC Building 7 program. He says it's not because of thermite, but because of conditions under the Pile.

TexasJack, I don't think you were aware of this article. It's a dilly. Keep up the good work.

 

[bill smith]

I can't believe Heiwa is managing to waste everyone's time so successfully after several years of being pwned. His favorite tactic on the JREF forums is to sprout a new thread and park there, using a long list of debunked ideas to fuel fake controversy here.

I haven't yet compiled an extensive list of this deceptive and manipulative person's activities, but he has claimed to have 1 million dollars if someone can meet his challenge. As yet, I haven't seen on iota of proof that he actually has access to 1 million dollars, so at this point it appears to be an outright fraudulent claim.
Why is this kind of thing tolerated on the forums? Unless he's retracted the claim, but I can't find a reference to it.


http://www.internationalskeptics.com/forums/showthread.php?postid=4520696#post4520696

Anders also appears to be a no-planer :


29th July 2007, 12:21 AM

'
10 August, 2007

IMHO this guy is a pure troll, a permanent derail who is trying to exhaust rational thinkers on this forum by an endless game of revolving nonsense. It was only in March that he was fraudulently claiming to have 1 million, the denomination of which he refused to specify to Gravy, and since he has moved on to annoy everyone with new topics.

Why does anyone give him the time of day? I don't get it. If there ever was a good example of a troll, Heiwa's tactics would have to be near the top of the list.

His latest tactic, seen today on this thread, is to try to deny that there was sufficient sway of the towers when planes impacted. There is already plenty of eyewitness testimony which establishes the sway as a fact.

Heiwa is wasting everybody's time....again and again and again.....when is this going to stop?

The best way to get rid of guys like Heiwa is to beat him in his own game. Just get stuck in and wipe the floor with him with solid,honest engineering. Or better yet get Ray Mackey to come and have a final showdown with Heiwa.
That would do the trick. Shall we make a date for the final showdown at the jref corral ? ....Or perhaps not.......lol

 

[phil76]

Heiwa, simple:

Connections of floor 20 with columns fail, next floor 19, and so on ... Do you know why in a construction a column is never placed in the middle of a not reinforced floor ?

 

[Heiwa]

Heiwa, simple:

Connections of floor 20 with columns fail, next floor 19, and so on ... Do you know why in a construction a column is never placed in the middle of a not reinforced floor ?

Yes, of course! But where do you put a column in a ship that floats in water?

And why don't ships sink - one way crush down collapse - if you drop something on them?

Good! Newton's third law! And Arkimedes.

And that's Why a one-way Crush down is not possible.

 

[AndrewIlluminatus]

Reality is the top blocks of WTC 1 & 2 fell inside the outer tube of columns. Missed most if not all of the core columns and landed on the floor.

The reality is that if it was inside it could not be seen so this is not "reality" at all but a theory, a wild guess.

When the truss is clearly shown connected to the corrugated steel sheet onto which the steel re-bar reinforced concrete floor slab is poured and the truss is anyway cross-braced in a grid pattern, why would it bend-down from a local, asymmetrical, debris impact in one spot? The hypothetical local impact load would be distributed because the slab would act like a rigid drum surface. The truss system would remain firmly stuck to the underside of the floor. You have to shear off all the connections around the entire internal and external perimeter of the square donut floor pan to get it to try to pancake and it would still experience friction and resistance around the internal/external edges as it slid down.