9-11 Presentation at NMSR, May 19 2010

[Lyrandar]

It's a *********** rubble pile. I can't believe this is actually being taken as a serious argument.

My argument is that rubble sitting on top of a building cannot crush it. This is kindergarten-level understanding.

I have not seen any numbers on the force imparted by the rubble. Nor would I care, except to see who is willing to risk their career in claiming such utter nonsense.

... so you're relying entirely on common sense and arguments from incredulity?

In my high school and college physics courses, I've seen any number of instances where what common sense says should happen and what the equations say should happen disagree with each other. Every time we had a demonstration or lab exercise regarding such things, the equations "won" every time. In light of that, I hope you'll forgive me for saying that I don't trust your common sense very much without numbers to back it up.

 

[bill smith]

Why no "close-ups"? Wouldn't it be hard to see the stuff your looking for in wide or panoramic photos (IE wire mesh and mangled floor pans)?

Even you must know that photos like that could be faked anywhere and fed into the 9/1 narrative.

No, it's perfectly obvious that if there should be dozens of low aeriel shots, panoramic shots, detailed video and on and on. But there isn't.

You try mixing up 9.2 million square feet of wire mesh with assorted steel and concrete rubble and see if it's noticable. Think of rubble and chickenwire mixed which we've all seen at some time in our lives .

Remember--according to a gravity collapse NONE of that wire mesh should be missing. Or the 5,000 floorpans each 1,000 square feet in size

 

[DGM]

Even you must know that photos like that could be faked anywhere and fed into the 9/1 narrative.

No, it's perfectly obvious that if there should be dozens of low aeriel shots, panoramic shots, detailed video and on and on. But there isn't.

You try mixing up 9.2 million square feet of wire mesh with assorted steel and concrete rubble and see if it's noticable. Think of rubble and chickenwire mixed which we've all seen at some time in our lives .

Remember--according to a gravity collapse NONE of that wire mesh should be missing. Or the 5,000 floorpans each 1,000 square feet in size

What's your proof that there "missing"? These things can be seen in countless photos of the site. Are you saying the photos that show these things are fake?

You can make anything true if you ignore all "inconvenient" evidence.

 

[DGM]

Crap load of pictures Bill.

http://www.flickr.mud.yahoo.com/photos/stevenbaker/sets/72057594120224434/

 

[bill smith]

What's your proof that there "missing"? These things can be seen in countless photos of the site. Are you saying the photos that show these things are fake?

You can make anything true if you ignore all "inconvenient" evidence.

Go on....I'll let you pick out the most panoramic shots of the footprint of WTC1 . Don't drown me in photos now y'hear ? lol

 

[bill smith]

What's your proof that there "missing"? These things can be seen in countless photos of the site. Are you saying the photos that show these things are fake?

You can make anything true if you ignore all "inconvenient" evidence.

Hey DGM...where can I find a copy of that 'Toytown' Richard Gage video ? You know the one where debunkers added the kid's music ? You guys used to post that like there was no tomorrow but now I can't find it.

 

[pgimeno]

Please show the energetic analysis that indicates that rubble can crush an 80 or 90-storey building.

I already did. Greening's paper is an energetic analysis which takes into account the energy loss due to the dust mass exiting the system. From an energy point of view, rubble is just mass, despite your claim that "[t]he bowling ball does not have the same kinetic energy or momentum if it is pieces of bowling ball" (hopefully you take that back now, or otherwise would you care to put numbers into that by answering my question about the two halves of a bowling ball vs. a complete bowling ball?). The conversion of some of that energy into heat due to friction with itself or into sound, doesn't make much difference. Consider that each tower's GPE was about 115 tons of TNT, to try to figure out how much sound would they make if a significant part of that energy was converted into sound. Obviously it wasn't a significant part. For heat it's harder to estimate, but I'd say it was on par with sound.

I didn't know Bazant made predictions about demolitions.Why wouldn't he just ask demolitioners? What else does he predict? How long he'll remain employed at Northwestern?

I don't understand why you make these ridiculous questions. A physical model makes predictions about how things will behave in the real world. If the predicted behavior matches the one in real world, that helps in confirming the correctness of the model (though doesn't prove it). If they don't match, then that does prove the incorrectness of the model. Bazant predicted, through his model, how the top of the building would behave in these demolitions. They confirmed his prediction, thus helping confirming the correctness of his model.

Please cite where I claim that rubble is a fluid.

Why? I never said you did. However, sentences like these made me think you considered them to have so similar properties as to not be distinguishable:

Any directed stream of loose material or liquid can destroy things.

Because it is in many different pieces, i.e., not held together by anything, rubble "falling" on top of a building will mostly flow over and outside it, not through it, except perhaps for some larger chunks.

That sounds like attributing fluid properties to rubble, so,I wanted to make it perfectly clear to you that there are important differences in their behavior, including their tendency to "spill" as demonstrated by the video.

"Which was a significant part".... "because we need it to be!"

Wrong. Because the current estimations on the total amount of mass loss due to dust ejection points in that direction, plus it's just how debris (which is not a fluid, remember) can possibly behave with such a massive structure.

Magically, stationary inertia overcomes gravity in this argument, but only around the sides of the rubble, so that it doesn't spill over the sides!

I don't understand that assertion. Inertia has a role in not spilling rubble to the sides very quickly, and gravity has a role in pushing rubble down. If the collapse were magically arrested at, say, half the trajectory, we would end up having on top of the half tower a mountain of debris which would slowly (as compared to floor crushing speed) spill until a certain amount of debris remained there.

Maybe you should answer TrutherLie's question to me: Which would you rather stand under, a kilo of bricks or a kilo of feathers?

I don't think that's relevant. Let me show you why with another example: what would you rather stand under, a kilo of nails or a 1-kilo pillow?

 

[ergo]

I don't think that's relevant. Let me show you why with another example: what would you rather stand under, a kilo of nails or a 1-kilo pillow?

You don't think that's relevant but nails vs. pillows is? LOL. Answer: pillow. Mainly because nails would hurt.

 

[ergo]

I already did. Greening's paper is an energetic analysis which takes into account the energy loss due to the dust mass exiting the system.

This is not an analysis of the energy required for rubble to crush through a 90-storey building.

From an energy point of view, rubble is just mass, despite your claim that "[t]he bowling ball does not have the same kinetic energy or momentum if it is pieces of bowling ball"

(hopefully you take that back now, or otherwise would you care to put numbers into that by answering my question about the two halves of a bowling ball vs. a complete bowling ball?).

I don't know what question you are referring to.

The conversion of some of that energy into heat due to friction with itself or into sound, doesn't make much difference.

This wasn't my argument. It was the Almond's argument. I agree. It's stupid.

I don't understand why you make these ridiculous questions. A physical model makes predictions about how things will behave in the real world. If the predicted behavior matches the one in real world, that helps in confirming the correctness of the model (though doesn't prove it). If they don't match, then that does prove the incorrectness of the model. Bazant predicted, through his model, how the top of the building would behave in these demolitions. They confirmed his prediction, thus helping confirming the correctness of his model.

Those types of demolition were occurring before Bazant ever set pen to paper. He didn't "predict" anything about it. He may have inferred some principle from it and incorrectly applied it to the Twin Towers.

Wrong. Because the current estimations on the total amount of mass loss due to dust ejection points in that direction, plus it's just how debris (which is not a fluid, remember) can possibly behave with such a massive structure.

No, it's not how debris will behave, and it's certainly not the only way "it possibly can" behave.

I don't understand that assertion. Inertia has a role in not spilling rubble to the sides very quickly, and gravity has a role in pushing rubble down.

Lol. Only some of the rubble is being affected by gravity? The "crushing" portion of it? ALL of the rubble is affected by gravity. Because it is loose material its independent components will behave independently. This means gravity will be pulling the looser pieces on top down over the pile and to the side. You can see this with any mound of particulate matter you pour onto a Table top. Try sea salt, or even wet sand, which sticks in clumps. It does not layer. It does not pile vertically. Even if you put a cigar box on top of it, crushing it between the box and the table, it will not pile vertically.

If the collapse were magically arrested at, say, half the trajectory, we would end up having on top of the half tower a mountain of debris which would slowly (as compared to floor crushing speed) spill until a certain amount of debris remained there.

Again, lol. You're saying that gravity pulls debris through an intact building (which has now arrested the crush-down) faster than it would pull debris down and over the pile? It doesn't work that way.

 

[triforcharity]

I trust pictures a lot more than I trust people whe it comes to 9/11 DGM. Especially early pictures where they may have been revealing more than they knew.

Do you have any panoramic photos of the rubble pile in the footprint of WTC1 ? No closeups Wide or panoramic shots only.

Here you go Bill. Care to count the columns?

http://upload.wikimedia.org/wikipedia/commons/f/f5/Wtc-photo.jpg

 

[TruthersLie]

Maybe you should answer TrutherLie's question to me: Which would you rather stand under, a kilo of bricks or a kilo of feathers?

I love the bad reading... YET AGAIN.

I didn't say a kilo did I?

Damn... you really do need to take a reading for comprehension class...

You still haven't told me how that car was crushed by a fluid made up of "loose" particles.

and your inability to read for comprehension has foiled you again....

 

[TruthersLie]

{more idiocy deleted for clarity}

Again, lol. You're saying that gravity pulls debris through an intact building (which has now arrested the crush-down) faster than it would pull debris down and over the pile? It doesn't work that way.

I love these strawman arguments you keep trying to pass off.

First we have the
"it fell in 13 seconds" which is incorrect. The first tower fell in about 15 seconds, the second over 20+ seconds and wtc7 took over 18 seconds to collapse.

Then you have stated several times that the towers would arrest the collapse, which is a ******** strawman.

The collapse was NOT arrested, hence you would not have gravity pullng the debris outside the building. You have tried that 2x so far. And you are WRONG about it. Both times.

Buildings are built with two items in mind. Static loads, and dynamics loads and almost always are NOT the same amount.

You keep arguing from incredulity, back it up with facts, numbers, mathematics.

That is like a high school physics student stating
If two cars get into a head on collision and both are going 50 MPH, then it would be the same thing as if ONE car going 100 MPH hit a solid wall.

Which is incorrect because it is counterintuitive....

 

[pgimeno]

This is not an analysis of the energy required for rubble to crush through a 90-storey building.

Please explain why not.

I don't know what question you are referring to.

Actually, questions, plural:

You say that a bowling ball in pieces wouldn't have the same kinetic energy or momentum as a whole bowling ball (I assume you mean with the same total mass and velocity).

Please give a quantification of it in this simplified example: imagine a bowling ball split in half, with the two halves moving together.

1. How much energy do the combined two halves do, as compared to a whole ball?

2. Assuming you can survive an impact of half a bowling ball but not a whole bowling ball, would you survive an impact of the two halves together?

The conversion of some of that energy into heat due to friction with itself or into sound, doesn't make much difference.

This wasn't my argument. It was the Almond's argument. I agree. It's stupid.

But that leaves you with the need to explain where the energy drain lies. So far you haven't but asserted again and again that the energy is not the same, but you're disregarding the reasons for energy loss. The only reasons for a difference I can think of are the conversion of energy into sound or heat, or the exit of energetic mass from the system. You also disregard Dr. Greening's study which deals with the amount of dust that left the towers. Where's the energy drain then? Your answer to the bowling ball question above can shed some light on this.

Those types of demolition were occurring before Bazant ever set pen to paper. He didn't "predict" anything about it. He may have inferred some principle from it and incorrectly applied it to the Twin Towers.

Speculation. He elaborated a complete physical model based on math. His math proved to match the physical world, which corroborates his findings. Math is just one way, you can't make math tell you lies unless it's wrong math.

No, it's not how debris will behave, and it's certainly not the only way "it possibly can" behave.

You keep denying it again and again, without giving any argument except the loss of mass from the system due to the spilling or flowing. I have give you arguments on the inertia of the particles, on the way that pulverized concrete forms mountains without spilling or flowing, and you have just shown incredulity in response.

Lol. Only some of the rubble is being affected by gravity? The "crushing" portion of it? ALL of the rubble is affected by gravity. Because it is loose material its independent components will behave independently. This means gravity will be pulling the looser pieces on top down over the pile and to the side. You can see this with any mound of particulate matter you pour onto a Table top. Try sea salt, or even wet sand, which sticks in clumps. It does not layer. It does not pile vertically. Even if you put a cigar box on top of it, crushing it between the box and the table, it will not pile vertically.

So what? The pulverized mountains I showed you, which are only dust while rubble in the WTC was not, supported an about 45° piling. A 45° pyramid over a 4,000 m² area (the approximate area of each WTC floor) has a volume of about 42,000 m³. The volume of the WTC1 top was about 182,000 m³, of which about 90% was air, leaving about 18,200 m³ of rubble. The whole WTC1 top would fit within that pyramid. Its mass has already been shown to be able to crush the lower floors.

But you're wrong on that too. The WTC rubble layer was under the pressure of the top. Try to pour sand on a table and press it with a glass, and see how much of it remains in place and how much spills out of the area of the glass. And we're not talking sand. We're talking also big pieces of steel and concrete, plus other building contents. Steel components are not sand. Are you comparing sand with steel?

Again, lol. You're saying that gravity pulls debris through an intact building (which has now arrested the crush-down) faster than it would pull debris down and over the pile? It doesn't work that way.

Says who? Or even better, why? Remember that the fall speed was about 2/3 gravity, which means that the pile experienced about 1/3 gravity, not full gravity.

 

[femr2]

Greening's paper is an energetic analysis which takes into account the energy loss due to the dust mass exiting the system.

What Greening paper are you referring to ? If "ENERGY TRANSFER IN THE WTC COLLAPSE", then, no, it doesn't take account of any mass exiting the system.

This is not an analysis of the energy required for rubble to crush through a 90-storey building.

Please explain why not.

If it's the above paper, then it uses simple 1D point-masses. No treatment of rubble is performed. If not that paper, could you post a link ?

Note I'm only highlighting as, given the original intention over on the Bazant thread to ensure *correctness* of interpretation and application, consistency across threads seems like a good idea.

He elaborated a complete physical model based on math. His math proved to match the physical world, which corroborates his findings.

The Bazant model cannot, and was never intended to, match real world behaviour. As highlighted on t'other thread, even the terms *crush-up* and *crush-down* can only be loosely applied to the towers...

In the real WTC situation, we don't have a true "crush down / crush up" anyway. What actually happens is the core and perimeter structure of the lower block funnels falling material onto the floors. The truss floors preferentially fail downward, whereas the beam-framed floors in the core preferentially fail upward.

In the scenario above, shortly after initiation there is no real semblance of upper block remaining. There are several zoned debris avalanches causing essentially internal pancaking, with a tangled mess of core lagging behind and sections of perimeter either being ejected or peeling even further behind. In addition, whilst floor destruction progressed to ground, partial core destruction was arrested.

My original post to you on this point seems to have been moved out of that thread for some bizarre reason, but it's here for reference...
Post #2

 

[beachnut]

...

The Bazant model cannot, and was never intended to, match real world behaviour. As highlighted on t'other thread, even the terms *crush-up* and *crush-down* can only be loosely applied to the towers...

...

But it does. If you were an engineer you would have a better appreciation for models (if you did not have delusions about 911). The Bazant model brings out the failure in your CD delusion. It is like flypaper, catching the wannabe engineer attacking a model he can't refute. The core can't stand without the shell (BTW).

What about the Pentagon? How does that fit in your CD theory? (very much on topic)

 

[ergo]

In the scenario above, shortly after initiation there is no real semblance of upper block remaining. There are several zoned debris avalanches causing essentially internal pancaking, with a tangled mess of core lagging behind and sections of perimeter either being ejected or peeling even further behind. In addition, whilst floor destruction progressed to ground, partial core destruction was arrested.

So you are agreeing that the Bazant/NIST model of progressive collapse (aka "official collapse theory") is not tenable. If the model is not correct, how is it that the calculations for the energy required for a complete collapse nevertheless remain correct?

 

[ergo]

Please explain why not.

Well, I was going to say because, as you said: "Greening's paper is an energetic analysis which takes into account the energy loss due to the dust mass exiting the system," which obviously is not an explanation of the energy required for rubble to crush through a building. But I think femr2's reply is better.

Actually, questions, plural: Please give a quantification of it in this simplified example: imagine a bowling ball split in half, with the two halves moving together.

1. How much energy do the combined two halves do, as compared to a whole ball?
2. Assuming you can survive an impact of half a bowling ball but not a whole bowling ball, would you survive an impact of the two halves together?

I can't give you a quantification. Why do you ask about the "combined" two halves? They are moving independently. I have no idea if I would survive an impact by two bowling ball halves. I would guess that yes, I would, because if I can survive one, then I can survive two.

But that leaves you with the need to explain where the energy drain lies. So far you haven't but asserted again and again that the energy is not the same, but you're disregarding the reasons for energy loss. The only reasons for a difference I can think of are the conversion of energy into sound or heat, or the exit of energetic mass from the system. You also disregard Dr. Greening's study which deals with the amount of dust that left the towers. Where's the energy drain then? Your answer to the bowling ball question above can shed some light on this.

I've already explained it at least once here. . The energy losses have also been explained ad nauseum by real scientists. If your eyes are glossing over whenever you come to those descriptions, I can't help that.

Speculation. He elaborated a complete physical model based on math. His math proved to match the physical world, which corroborates his findings. Math is just one way, you can't make math tell you lies unless it's wrong math.

His math may apply to verinage. It does not apply to the WTC.

You keep denying it again and again, without giving any argument except the loss of mass from the system due to the spilling or flowing. I have give you arguments on the inertia of the particles, on the way that pulverized concrete forms mountains without spilling or flowing, and you have just shown incredulity in response.

No, I've given you other arguments about the rubble. Not just how it spills but how it will respond differentially to a force from above and to gravity.

But, regarding your mountains, "pulverized" concrete would spill, because pulverization implies reducing to a fine consistency. If you're referring to concrete chunks, how does a "mountain" form in a process that is as dynamic as we see in the videos? And, while we're on the videos, can you show us where these are in the visual evidence? Thanks.

So what? The pulverized mountains I showed you, which are only dust while rubble in the WTC was not, supported an about 45° piling. A 45° pyramid over a 4,000 m² area (the approximate area of each WTC floor) has a volume of about 42,000 m³. The volume of the WTC1 top was about 182,000 m³, of which about 90% was air, leaving about 18,200 m³ of rubble. The whole WTC1 top would fit within that pyramid. Its mass has already been shown to be able to crush the lower floors.

Again, please provide visual evidence of these mountains. And, as I've already stated, the mass of a collection of chunks and particles will not have the same kinetic energy as the mass of an intact block.

Says who? Or even better, why? Remember that the fall speed was about 2/3 gravity, which means that the pile experienced about 1/3 gravity, not full gravity.

Which probably explains why it cannot crush through a 90-storey building.

 

[femr2]

So you are agreeing that the Bazant/NIST model of progressive collapse (aka "official collapse theory") is not tenable.

That is not what I am saying at all. NIST has nothing to do with this discussion. My purpose is to make sure that the abstracted Bazant model is not applied literally to real world behaviour. That is incorrect. In terms of energetics, the model shows that, even in the ideal case, enough energy was available for destruction for the given initial simplifying assumptions.

If the model is not correct, how is it that the calculations for the energy required for a complete collapse nevertheless remain correct?

It is a limiting case mathematical model. It is important to understand it's context and limited applicability to the real world behaviour.

 

[Myriad]

Discussion of moderation issues removed. Please stay on topic.

Replying to this modbox in thread will be off topic  Posted By: Myriad

 

[ergo]

"Limited applicability" is an understatement. Moreover, it's scientifically invalid to claim that a model "shows" that there is enough energy for a complete collapse, even though the model doesn't apply to what actually happened.

And why are you making distinction between Bazant and NIST here? How do they differ significantly?