WTC 1 & 2. What happened after collapse initiation?

[applecorped]

Because it didn't happen.

**EDIT**

Yes, there were explosions. No, it wasn't a CD.

 

[Jonnyclueless]

Tanabear, it depends on how you mean. It did not pancake in the sense of the floors falling independently of the columns. But it did pancake in the sense that the collapse happened floor by floor and no floors fell until the floor above impacted it. And of course none of this was prior to the collapse initiation which was based on the columns being pulled together.

 

[Cl1mh4224rd]

I'm saying that it isn't controversial to suggest that explosive charges can destroy buildings. It is only controversial in regards to WTC1,2 and 7.

In the case of the Twin Towers, that would be because no building has ever been destroyed using explosives in a manner resulting in a visually similar collapse.

In the case of all three towers, that would be because there are tell-tale signs missing (namely, the highly audible and rapid sequence of explosions prior to the building's collapse, and a seismic record).

 

[NobbyNobbs]

WTC1:s structure was very much like a cheese. Something slammed into it and made a hole in the cheese, fire erupted and the cheese started to melt around the hole. Above the hole was a big, upper block of 33 000 tons of cheese. Below the hole was a much bigger block of cheese! 250 000 tons.
Now we are told the upper block started to move down, releasing potential energy, as the cheese below was melting around the hole. The upper cheese block, 33 000 tons, hits the lower cheese block, 250 000 tons, and compresses it. The hole disappears and molten cheese is squeezed out. What happens then?

Cheese structure has built in strength that can absorb potential energy. The strength can be likened to the amount of strain energy the hard cheese can absorb before being crushed. The amount of strain energy is almost constant per ton of cheese. Same in the upper and lower cheese parts.

Simple math shows that 33 000 tons of cheese above cannot compress 250 000 tons of cheese below when both parts absorb the same amount of strain energy at the compression. No global collapse.

Unless you fit some extra stuff in the lower cheese. But then cheese rubble and debris are ejected in all directions and reveals the bluff.

Cheese? The latest theory is cheese?

Ok, Heiwa, since 33,000 tons falling down on 250,000 can't possibly damage the bottom part, I'm sure you won't have any problem performing the following experiment. 33,000 is about 13% of 250,000. I'm going to be generous and assume that you weigh about 100 pounds. So, all you need to do is go out, find a 13 pound bowling ball, drop it on your head, and see if there's any (more) damage. According to your theory, you should be perfectly safe. Care to test it?

There is, as you know, no such animal as the "no building theory."

There should be. It can't be any worse than the "cheese theory". I think it might be pretty gouda. (I'm such a muenster!)

 

[X]

So when the upper block crushed the lower block, did it break apart while it was crushing, or did it remain intact while it was destroying the lower block, only to be destroyed itself when it came in contact with the rubble pile. Bazant et al suggest the latter. In other words, did the crush-down and crush-up occur simultaneously or at separate times?

To be honest, I do not know. Ask Bazant, et al.

Ultimately, it does not matter much.
Whether the upper section is destroyed during or after the collapse should not appreciably change the amount of mass moving downwards.

The important thing to note is that the moving mass put more strain on the lower section than the lower section could withstand.

 

[funk de fino]

tanabear yet again in 277 shows he does not understand the difference between the collapse initiation and what happened during the progressive collapse

the floors pancaked during the collapse but this was not what caused the collapse

i cannot put it any clearer than that

 

[e^n]

So when the upper block crushed the lower block, did it break apart while it was crushing, or did it remain intact while it was destroying the lower block, only to be destroyed itself when it came in contact with the rubble pile. Bazant et al suggest the latter. In other words, did the crush-down and crush-up occur simultaneously or at separate times?

This is not what Bazant et al suggest. They suggest that as the upper block impacts the lower block, a section of both blocks will be crushed to rubble. Some of this mass will be ejected over the side, but crucially as the mass is now located one floor above the next concrete slab, the entire mass will accelerate at 9.81m/s/s and impact the next floor. The majority of energy exerted here will be against the already significantly damaged crushed mass which consists of elements of both the upper and lower block. The reason the upper block is not more significantly damaged is that in most situations it is accelerating at the same rate as the crushed mass.

One of the goals of this thread was to attempt to clear up some confusion because many debunkers still insist that the official explanation is that the floors pancaked. As prominent 9/11 debunker Ronald Wieck has stated, "Once the global collapse ensued, the floors necessarily pancaked. What else could they be expected to do?"

Other people have adequately dealt with this, but you should read some of the accounts of cleanup crews, there are at least 3 or 4 different people talking about seeing 14 floors compacted together.

So if only the top two floors fell onto the lower structure it would destroy the entire building? If that was the case then the World Trade Center towers were the worst designed buildings in history.

If the top two floors exceed the ability of columns and floor sections to resist, then yes it would collapse. Why do you think they were terribly designed? What possible event could cause the top two floors to fall?

I'm saying that it isn't controversial to suggest that explosive charges can destroy buildings. It is only controversial in regards to WTC1,2 and 7. People can accept the fact that explosions can destroy buildings. They can't accept this when it comes to 9/11. Why not?

People have no problems agreeing that explosives can demolish buildings, but you are making a false claim here, you are misrepresenting the views of others. People are sceptical that explosives would do the job of destroying the buildings according to the video, audio and eyewitness evidence. This is a required implication of your claim and of course you seem to be ignoring it.

 

[bje]

So if only the top two floors fell onto the lower structure it would destroy the entire building? If that was the case then the World Trade Center towers were the worst designed buildings in history.

I am not asking for your feelings, Tanabear. I am asking for your evidence that the buildings were designed to support the weight of each top section of towers that fell on the bottom structure.

Please reference factual material that demonstrates the towers were designed to support the falling mass of each tower.

 

[R.Mackey]

That was exactly my point. There is no pancaking going on, at least according to what can now be considered the official story. Brent Blanchard also made the same point as Shyam Sunder, "As many are aware - and as we go on to explain later in Assertion #2 - the buildings did not actually 'pancake'. Our use of the word is not intended to be taken literally, rather it is used to represent a general visual description that helps readers conceptualize the more advanced points that follow."

One of the goals of this thread was to attempt to clear up some confusion because many debunkers still insist that the official explanation is that the floors pancaked. As prominent 9/11 debunker Ronald Wieck has stated, "Once the global collapse ensued, the floors necessarily pancaked. What else could they be expected to do?"

Color added for emphasis.

You asked about initiation. I told you about initiation.

Ron Wieck's words refer to conditions after initiation. His words are accurate.

Seriously, are you just dishonest, or what?

 

[BenBurch]

...
Seriously, are you just dishonest, or what?

That would seem to me to be a good guess.

 

[pomeroo]

The liars have fled to lick their wounds. But they will return to recycle the same garbage.

 

[tanabear]

To be honest, I do not know. Ask Bazant, et al.

Ultimately, it does not matter much.
Whether the upper section is destroyed during or after the collapse should not appreciably change the amount of mass moving downwards.

The important thing to note is that the moving mass put more strain on the lower section than the lower section could withstand.

But if the upper block has been largely destroyed, how can it continue to pulverize the non-metallic portions of the building? It is far less dense, and much of it is falling outside of the footprint.

tanabear yet again in 277 shows he does not understand the difference between the collapse initiation and what happened during the progressive collapse

the floors pancaked during the collapse but this was not what caused the collapse

i cannot put it any clearer than that

That is because "pancake initiation" is a meaningless phrase. If a building is going through a pancake initiation, what exactly is happening to the structure?

This is not what Bazant et al suggest. They suggest that as the upper block impacts the lower block, a section of both blocks will be crushed to rubble. Some of this mass will be ejected over the side, but crucially as the mass is now located one floor above the next concrete slab, the entire mass will accelerate at 9.81m/s/s and impact the next floor. The majority of energy exerted here will be against the already significantly damaged crushed mass which consists of elements of both the upper and lower block. The reason the upper block is not more significantly damaged is that in most situations it is accelerating at the same rate as the crushed mass.

"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."
Bazant et al.

Color added for emphasis.

You asked about initiation. I told you about initiation.

Ron Wieck's words refer to conditions after initiation. His words are accurate.

Seriously, are you just dishonest, or what?

So are you now saying that the floors did pancake? Are you trying to play Humpty Dumpty so you can redefine words and phrases to mean whatever you want them to mean? You wrote in a previous thread,

"After a few floors collapse, the upper block is riding on a cushion of debris, and relatively smooth behavior is guaranteed... I see no anomaly here at all."

I then asked you, "The upper block is riding a cushion of debris????? If the upper is riding a cushion of debris then how does it crush the lower block? Or is this "cushion of debris" crushing the lower part of the tower?"

You responded, "Keep in mind the "cushion" is assorted steel, concrete, and other building products; weighs tens to hundreds of thousands of tons at various times in its evolution; and travels at tens to hundreds of meters per second. It will quickly become larger than the upper block, and it is responsible for most of the crushing.

"It's only a cushion in that it fills voids and smears the impulses by a fraction of a second. This is why the upper block doesn't experience a periodic series of discrete impacts. In every other respect, there is nothing soft or comfortable about the "cushion."'

So where does pancaking come into play in your previous explanation? The pancake collapse explanation has to do with one floor impacting the floor beneath it, leading to a chain reaction of floors falling on top of one another causing the building to completely collapse. How is pancaking(floors impacting floors) consistent with your previous explanation? You have an upper block separated from the lower block by a cushion of debris. And this cushion of debris is responsible for most of the crushing. That doesn't sound like pancaking, unless pancaking can mean whatever you want it to mean.

The other issue this brings up is how the debunkers have trouble describing what actually happened to the towers after "collapse initiation." The use ambiguous words and ill-defined phrases are necessary to prevent their explanations from becoming falsified. It is important for the debunkers to be vague, because once they state clearly what they believed happened to the towers after initiation, then it is possible to show where they are wrong. The goal of the debunkers is to engage in semantic games to avoid providing a serious explanation of how the towers were destroyed. This is how a cult operates, not those seeking the truth.

 

[R.Mackey]

But if the upper block has been largely destroyed, how can it continue to pulverize the non-metallic portions of the building? It is far less dense, and much of it is falling outside of the footprint.

It is not far less dense. Destroyed or not destroyed, the upper block has the same specific gravity as the lower block. It's made of the same materials. Very little falls outside the footprint early on -- it can't. It hasn't hit enough stuff to impart enough momentum to move that material.

That is because "pancake initiation" is a meaningless phrase. If a building is going through a pancake initiation, what exactly is happening to the structure?

It is not a meaningless phrase. I explained it to you two posts back. "Pancake initiation" means the collapse started because floors came loose from the columns, triggered other floor connection failures, and thereby destabilized the columns. Quite meaningful. And in WTC 1 and 2 it did not happen.

So are you now saying that the floors did pancake? Are you trying to play Humpty Dumpty so you can redefine words and phrases to mean whatever you want them to mean?

I even wrote the word initiation in bold, large, red type, and you still missed it.

I am not pulling any Carrollian tricks of language. You simply can't read. Try again:

At initiation, there is no pancaking. Collapse is caused by buckling of columns with floors still attached. The attachment is central to the model.

Long after initiation, there is pancaking. We know this because a very large remnant of the core survived after the collapse had passed it, for a few seconds anyway. At this stage, floors are detaching at the connections, which should surprise no one.

The mistake you make, I'm beginning to suspect out of breathtaking idiocy, is to equivocate initiation and not initiation. Ergo, the one playing Humpty Dumpty is you.

Before you asked about initiation, and that's what I told you about. Your mistake was assuming the mechanism at initiation was the same as the mechanism all the way to the ground. Obviously, this is a bad assumption.

Keep reading the above until you understand.

The other issue this brings up is how the debunkers have trouble describing what actually happened to the towers after "collapse initiation." The use ambiguous words and ill-defined phrases are necessary to prevent their explanations from becoming falsified. It is important for the debunkers to be vague, because once they state clearly what they believed happened to the towers after initiation, then it is possible to show where they are wrong. The goal of the debunkers is to engage in semantic games to avoid providing a serious explanation of how the towers were destroyed. This is how a cult operates, not those seeking the truth.

We have no trouble describing this, nor is there any "cult." You are simply fabulously ignorant.

 

[Jonnyclueless]

Yes, one person can't seem to comprehend the most basic physics that everyone else has no trouble understanding. But it clearly is the fault of everyone else...

 

[twinstead]

Yes. Since when is the majority, holding the majority view, backed up by the majority of experts a 'cult'?

 

[phunk]

But if the upper block has been largely destroyed, how can it continue to pulverize the non-metallic portions of the building? It is far less dense, and much of it is falling outside of the footprint.

It's actually far denser after being crushed, as the big airspaces between the floors are removed.

 

[X]

But if the upper block has been largely destroyed, how can it continue to pulverize the non-metallic portions of the building? It is far less dense, and much of it is falling outside of the footprint.

Did you even read my post?
Here, I'll quote it below for you to read again.
This time, I will bold the section that contains the answer to your question.

To be honest, I do not know. Ask Bazant, et al.

Ultimately, it does not matter much.
Whether the upper section is destroyed during or after the collapse should not appreciably change the amount of mass moving downwards.

The important thing to note is that the moving mass put more strain on the lower section than the lower section could withstand.

Do you understand what I bolded?
The density does not matter (and it will be more dense, not less). The moving mass is what matters. And as has been pointed out, not much is falling outside the building. And what does fall away is more than made up for by the added mass from the floors of the lower section that are destroyed.

 

[tanabear]

Answering Heiwa's question.

Heiwa on his website asks the following question,

"How can serious authorities and scientists suggest that a global collapse or crush down of WTC 1 is driven only by gravity and an indestructible upper block when the latter - as a smoking gun - disappears before the collapse even starts as per fig. 8 and all videos?"

This question is answered by Bazant and others in some of their papers. In the paper, "Mechanics of Progressive Collapse: Learning from World Trade Center and Building Demolitions", by Bazant and Verdue, they write,

"Due to a shroud of dust and smoke, the videos of the World Trade Center are only of limited use."

"Because of the shroud of dust and smoke, these histories can be identified from the videos of the collapsing WTC towers only for the first few seconds of collapse, and so little can be learned in this regard from that collapse."

"Approximate information could be extracted from a regular video of collapse, but only for the first few seconds of collapse because later all of the moving part of the WTC towers became shrouded in a cloud of dust and smoke..."

In the paper, "What Did and Did not Cause Collapse of WTC Twin Towers in New York" by Bazant, Greening, Benson and Le, they write,

"Video records in which the motion of the tower top can be tracked are available for the first few seconds, until the tower top gets shrouded by a cloud of dust and smoke."

These are interesting statements to make. I like the first comment best, "the videos of the World Trade Center are only of limited use." Now why are the videos of limited use? The video tapes show what happened to the towers over the 15 or so seconds as they were being destroyed. The video tape record provides the best empirical evidence to explain what happened to the towers. So why is it only useful for the first couple of seconds?

What Bazant means is that the video evidence is only useful for his theory for the first couple of seconds, then the evidence begins to contradict his hypothesis. For those that follow Bazant's model, they treat the clouds of dust and smoke as some sort of exogenous factor. The building is collapsing then all of a sudden all these dust clouds obscure what is really happening.

Let's take another example. Assume a crime is getting ready to be committed. Three people have decided to rob a bank. Then right as they begin to rob the bank someone sets off a huge smoke bomb obscuring the view so the security camera can only catch the first few seconds of the crime being committed. In such a situation the video evidence might be of limited use.

This is how Bazant treats the huge dust clouds, something that hides what is really happening to the building. This is incorrect. The production of these massive dust clouds tells us what is happening to the towers, it doesn't hide what is happening. I, therefore, believe the video evidence is useful for the entire duration of the towers destruction.

Bazant has decided that his mathematical model provides a better illustration of what happened to the towers than the actual video tape evidence. If the world of reality does not agree with my mathematical model then so much worse for the world of reality.

So "how can serious authorities and scientists suggest that a global collapse or crush down of WTC 1 is driven only by gravity and an indestructible upper block...?"

By ignoring the evidence. Bad Science. Good Propaganda.

 

[pomeroo]

Answering Heiwa's question.

Heiwa on his website asks the following question,

"How can serious authorities and scientists suggest that a global collapse or crush down of WTC 1 is driven only by gravity and an indestructible upper block when the latter - as a smoking gun - disappears before the collapse even starts as per fig. 8 and all videos?"

This question is answered by Bazant and others in some of their papers. In the paper, "Mechanics of Progressive Collapse: Learning from World Trade Center and Building Demolitions", by Bazant and Verdue, they write,

"Due to a shroud of dust and smoke, the videos of the World Trade Center are only of limited use."

"Because of the shroud of dust and smoke, these histories can be identified from the videos of the collapsing WTC towers only for the first few seconds of collapse, and so little can be learned in this regard from that collapse."

"Approximate information could be extracted from a regular video of collapse, but only for the first few seconds of collapse because later all of the moving part of the WTC towers became shrouded in a cloud of dust and smoke..."

In the paper, "What Did and Did not Cause Collapse of WTC Twin Towers in New York" by Bazant, Greening, Benson and Le, they write,

"Video records in which the motion of the tower top can be tracked are available for the first few seconds, until the tower top gets shrouded by a cloud of dust and smoke."

These are interesting statements to make. I like the first comment best, "the videos of the World Trade Center are only of limited use." Now why are the videos of limited use? The video tapes show what happened to the towers over the 15 or so seconds as they were being destroyed. The video tape record provides the best empirical evidence to explain what happened to the towers. So why is it only useful for the first couple of seconds?

What Bazant means is that the video evidence is only useful for his theory for the first couple of seconds, then the evidence begins to contradict his hypothesis. For those that follow Bazant's model, they treat the clouds of dust and smoke as some sort of exogenous factor. The building is collapsing then all of a sudden all these dust clouds obscure what is really happening.

Let's take another example. Assume a crime is getting ready to be committed. Three people have decided to rob a bank. Then right as they begin to rob the bank someone sets off a huge smoke bomb obscuring the view so the security camera can only catch the first few seconds of the crime being committed. In such a situation the video evidence might be of limited use.

This is how Bazant treats the huge dust clouds, something that hides what is really happening to the building. This is incorrect. The production of these massive dust clouds tells us what is happening to the towers, it doesn't hide what is happening. I, therefore, believe the video evidence is useful for the entire duration of the towers destruction.

Bazant has decided that his mathematical model provides a better illustration of what happened to the towers than the actual video tape evidence. If the world of reality does not agree with my mathematical model then so much worse for the world of reality.

So "how can serious authorities and scientists suggest that a global collapse or crush down of WTC 1 is driven only by gravity and an indestructible upper block...?"

By ignoring the evidence. Bad Science. Good Propaganda.

You may have noticed that Heiwa is an incompetent fool who actually claims that dropping the top third of a building on the bottom two-thirds from a height of two miles will merely establish a "new equilibrium." This is the idiot you are citing??

It is obvious that you know nothing about science. How will you manage to promote your mad fantasy when a NASA engineer is shredding your absurd pretensions?

 

[BenBurch]

You may have noticed that Heiwa is an incompetent fool who actually claims that dropping the top third of a building on the bottom two-thirds from a height of two miles will merely establish a "new equilibrium." This is the idiot you are citing??

It is obvious that you know nothing about science. How will you manage to promote your mad fantasy when a NASA engineer is shredding your absurd pretensions?

We have engineers, physicists, chemists, and architects here, all of whom know this is all woo, and these guys without a lick of scientific training think they can prove us wrong? Well, if they could, it would only be because they would have learned the science for themselves, and they are either too lazy or too stupid to do it.