Momentum Transfer in WTC

[TruthSeeker1234]

Consider Gordon Ross' paper:

http://worldtradecentertruth.com/Jou...ansferRoss.pdf
(remove space after h)

Frank Greening's attempted criticism:

http://worldtradecentertruth.com/Article_2_Greening.pdf
(remove space after h)
and Ross' reply to Greening:

http://worldtradecentertruth.com/Art..._RossReply.pdf
(remove space after h)

NIST, of course, did not attempt to do any calculations showing the possibility that the upper part of a damaged tower could cause the phenomenon we observe in the videos (i.e. the shredding of the steel and near total-pulverization of all other matter into fine powder).

Thus it appears that, at present, Ross is the last word on the subject.

Can anyone provide a refutation of Ross? I am not interested in the planes, or the fires. I am only interested in seeing calculations that show the possibility that the upper part of a skyscraper can crush the lower part, and itself, under the force of gravity.

In fact, let's not limit it to skyscrapers. I'd like to see any example of any object or structure, made of any material(s), of any average density, of any size (say between 1 inch to 100 miles) which meets the following two critera:

1. The object or structure is able to stand up against the force of gravity and retain its shape (i.e. generally behaves as a solid, not a liquid or a gas) for at least a year.

2. As a result of damage, an upper part of the object falls down into the lower part, and using no other source of energy apart from gravity, at least half of the mass is rendered into a fine powder of less than 100 micron average diameter.

[TruthSeeker1234]

I do not know why this was moved to "conspiracy theories" from "science and mathematics". I am not interested in any conspiracy theories on this thread. I am only interested in the science and math.

Thanks

[Lisa Simpson]

I moved it. You can still discuss the science here. But it belongs in this sub-forum.

Posted By:Lisa Simpson

[T.A.M.]

a little disingenuous coming in here and complaining about where a post is moved, when your selected username clearly indicates that you are a "Truth" seeker (9/11 "Truth" movement). But if I am wrong, than please tell me that you believe the official story about 9/11 and i will apologize. Otherwise, your post belongs right where it still sits.

Don't worry, if it is debate over the "Ross" paper you want, i am sure you will get it here.

TAM

[Gravy]

R. Mackey, whose posts are must-reads, points out several problems with Ross' paper: http://forums.randi.org/showpost.php...&postcount=576

[Pardalis]

Originally Posted by TruthSeeker1234

I do not know why this was moved to "conspiracy theories" from "science and mathematics". I am not interested in any conspiracy theories on this thread. I am only interested in the science and math.

Thanks

Yeah right, not with that screenname. Give me a break...

[R.Mackey]

Beat me to it.

What do you mean by "attempted" refutation? Greening is correct. Unless you're referring to how Ross, being on the board of editors of that "journal," is guaranteed the last word.

[Pardalis]

Originally Posted by TruthSeeker1234

In fact, let's not limit it to skyscrapers.

Why???

Skyscrapers are very unique constructions, especially the WTC towers. Why on earth would you want to compare it to... let's say... trees???

[TruthSeeker1234]

Mackey states

Quote:

The floor trusses are either failed or intact -- if failed, the top of the column is no longer constrained, and is free to deflect to the sides;

Nonsense. The 47 core columns were massively cross-braced, and not dependent on floor-trusses to constrain them.

[Gravy]

Originally Posted by TruthSeeker1234

at least half of the mass is rendered into a fine powder of less than 100 micron average diameter.

Your source for this contention?

[R.Mackey]

Originally Posted by TruthSeeker1234

In fact, let's not limit it to skyscrapers. I'd like to see any example of any object or structure, made of any material(s), of any average density, of any size (say between 1 inch to 100 miles) which meets the following two critera:

1. The object or structure is able to stand up against the force of gravity and retain its shape (i.e. generally behaves as a solid, not a liquid or a gas) for at least a year.

2. As a result of damage, an upper part of the object falls down into the lower part, and using no other source of energy apart from gravity, at least half of the mass is rendered into a fine powder of less than 100 micron average diameter.

On further inspection, it looks like you're not talking about Ross at all. All Ross's flawed whitepaper concerns is whether progressive collapse could initiate with a single floor. He deals only peripherally with the crumbling energy of other WTC materials.

I reject your challenge. Where do you get the idea that 50% of the mass of the WTC towers was "rendered into a fine powder of less than 100 micron average diameter?" This does not describe the debris seen after the collapses. What you've got here is a strawman.

[T.A.M.]

where's the popcorn, this looks like a good one.



TAM

[R.Mackey]

Originally Posted by TruthSeeker1234

Mackey states

Nonsense. The 47 core columns were massively cross-braced, and not dependent on floor-trusses to constrain them.

Cross-braced, by the floor trusses. I thought that was obvious.

Please read completely before criticizing. I also had a follow-up addressing Ross's "rebuttal" to Greening, found here. Happy reading.

[Belz...]

Originally Posted by TruthSeeker1234

Mackey states

Nonsense. The 47 core columns were massively cross-braced, and not dependent on floor-trusses to constrain them.

How is "massively" ?

[kevin]

Originally Posted by R.Mackey

Where do you get the idea that 50% of the mass of the WTC towers was "rendered into a fine powder of less than 100 micron average diameter?" This does not describe the debris seen after the collapses. What you've got here is a strawman.

What weighs more 100lb of concrete or 100lb of concrete power 100 micron average diameter?

[David Wong]

Originally Posted by TruthSeeker1234

Consider Gordon Ross' paper:
at least half of the mass is rendered into a fine powder of less than 100 micron average diameter.

Could anything short of a nuclear device do that?

No controlled demolition has ever turned half a building into powder, as far as I know.

[R.Mackey]

Originally Posted by kevin

What weighs more 100lb of concrete or 100lb of concrete power 100 micron average diameter?

The latter weighs more... on the mind of a 9/11 denier.

TruthSeeker, if you really wish to have an intelligent, abuse-free scientific discussion here, I'm game. Just say the word.

[TruthSeeker1234]

You're correct that Ross does not get into the dissociation of the non-metallic mass of the towers. He has calculated that global collapse is not possible under the circumstance. Figuring in the other observaions, such as the pulverization, only makes the "gravity did it" explanation more absurd. I will make that a sepearate thread, and name it the "TruthSeeker Challenge". Perhaps there will be a reward.

Many observes at ground zero, such as governor Pataki, commented on the near-complete absence of macro-concrete in the rubble, and the presence of powder "from river to river". I observe very dense clouds of powder falling very fast to the ground, and swelling out into rapidly progressing pyroclastic flows quickly became 3-4 times the volume of the intact tower. It certainly appears that entire towers were rendered almost totally into fine powder. If not, where did the concrete go? Where is the carpet? The computers? The pictures? Why was the biggest piece of non-metal that a rescue worker saw only "a half a keypad"?

Can someone link us to some photographic evidence of some stacked up concrete floors?

[Pardalis]

I'll leave this debate to the people who know their physics, but I'd like to ask Truthseeker to take note of this fallacy, which no one is immune to:

http://www.skepticwiki.org/wiki/inde...om_Incredulity

Just so that you are aware of it.

[Loss Leader]

Didn't NIST just clarify this?

Originally Posted by NIST Smacking The Truthers Silly

In other words, the momentum (which equals mass times velocity) of the 12 to 28 stories (WTC 1 and WTC 2, respectively) falling on the supporting structure below (which was designed to support only the static weight of the floors above and not any dynamic effects due to the downward momentum) so greatly exceeded the strength capacity of the structure below that it (the structure below) was unable to stop or even to slow the falling mass. The downward momentum felt by each successive lower floor was even larger due to the increasing mass.

[TruthSeeker1234]

Mackey, you are simply incorrect about the floor trusses being the only cross-bracing for the core columns. Look here, for instance:

http://www.peaceproject.com/graphics...s/CA2-huge.jpg

(add needed h t t p and w's)


Please retract your error, or lose credibility.

[R.Mackey]

Originally Posted by TruthSeeker1234

You're correct that Ross does not get into the dissociation of the non-metallic mass of the towers. He has calculated that global collapse is not possible under the circumstance. Figuring in the other observaions, such as the pulverization, only makes the "gravity did it" explanation more absurd. I will make that a sepearate thread, and name it the "TruthSeeker Challenge". Perhaps there will be a reward.

Except, as my posts referenced above point out, as does Greening, he did the calculation wrong. It's really a very bizarre argument that Ross is trying to promote.

No need for a "challenge." No stunts are necessary. If you can find holes in my reasoning, I'd like to hear about them. I am a scientist and I want to learn. But keep in mind that I will defend my opinions, trying to find out which of is right.

Originally Posted by TruthSeeker1234

Many observes at ground zero, such as governor Pataki, commented on the near-complete absence of macro-concrete in the rubble, and the presence of powder "from river to river". I observe very dense clouds of powder falling very fast to the ground, and swelling out into rapidly progressing pyroclastic flows quickly became 3-4 times the volume of the intact tower. It certainly appears that entire towers were rendered almost totally into fine powder. If not, where did the concrete go? Where is the carpet? The computers? The pictures? Why was the biggest piece of non-metal that a rescue worker saw only "a half a keypad"?

Can someone link us to some photographic evidence of some stacked up concrete floors?

I might remind you that concrete made up only a small fraction of the WTC tower mass.

The flows were not in any way "pyroclastic." I fear you are getting your information from disreputable sources. We've seen this misnomer for a long time.

If you're claiming 100 micron particles from the size of the debris cloud and eyeballing it, as in your "four to five times the volume of the intact tower" statement, then you need to research the debris much, much more carefully. No way you can make that claim.

Again, if you are serious about debating Ross's paper, please do so. You've seen my criticisms. But you will have to do much better than you have so far.

[DavidJames]

Originally Posted by TruthSeeker1234

You're correct that Ross does not get into the dissociation of the non-metallic mass of the towers. He has calculated that global collapse is not possible under the circumstance. Figuring in the other observaions, such as the pulverization, only makes the "gravity did it" explanation more absurd. I will make that a sepearate thread, and name it the "TruthSeeker Challenge". Perhaps there will be a reward.

Many observes at ground zero, such as governor Pataki, commented on the near-complete absence of macro-concrete in the rubble, and the presence of powder "from river to river". I observe very dense clouds of powder falling very fast to the ground, and swelling out into rapidly progressing pyroclastic flows quickly became 3-4 times the volume of the intact tower. It certainly appears that entire towers were rendered almost totally into fine powder. If not, where did the concrete go? Where is the carpet? The computers? The pictures? Why was the biggest piece of non-metal that a rescue worker saw only "a half a keypad"?

Can someone link us to some photographic evidence of some stacked up concrete floors?

So much for science Now you can see why the tread was (correctly) moved

[R.Mackey]

Originally Posted by TruthSeeker1234

Mackey, you are simply incorrect about the floor trusses being the only cross-bracing for the core columns. Look here, for instance:

peaceproject.com/graphics/postcards/CA2-huge.jpg

(add needed h t t p and w's)


Please retract your error, or lose credibility.

Fighting words indeed. None of this idiocy is necessary, if you are sincere. I won't back away from a friendly debate.

I note your image was taken during construction -- and is of extremely low quality. Please answer these questions first:

1) Which cross-bracing elements are you referring to in your picture?

2) What evidence do you have that they were permanent, rather than temporary bracing needed for construction?

3) What material are those elements made of? Your photo is in sepiatone and appears to be photocopied.

4) How are these elements attached to the columns?

After that, perhaps we can talk about credibility.

And you really should read my entire critique of Ross's paper. Your quote of me, out of context, only points out that Ross treated the problem one-dimensionally, assumed the columns would compress to failure, and that he is assuming columns are pinned on both ends.

As NIST has recently clarified, the actual collapse mechanism was highly three-dimensional in nature, with the columns being twisted into the interior, pulled in by sagging floor trusses at each floor.

If there are such huge cross-braces as you claim, these braces would be part of the load-bearing structure. Funny that not even Ross accounts energy to break them, as he would have to do, if they were real.

[TruthSeeker1234]

Mackey, of course pictures of the core are during construction. How could we photograph it after they were finsished? Come on. There is ample photographic evidence that the 47 core columns were horizontally and diagonally braced. Where is your evidence that they were not?

Next, there was about 100,000 tons of concrete per tower, which is about equal to the mass of the steel. Regardless, It appears almost everything besides the steel was rendered into fine powder. Otherwise, where is it?

Still waiting for the pictures of stacked up floors, or desks, or . . .anything.

Someone else upthread was wondering how much explosives it would take to bring the tower down, speculating it would take a nuke. Bear in mind that, using NIST logic, it would not take very much at all. NIST would have it that all that is needed is to initiate local collapse on one floor, gravity would do all the rest. Right?

Greening did point out what he felt were errors in Ross, which is why I linked his paper. Ross answered that even if Greening was right, it would only delay the halt of collapse by a fraction of a second.

[kevin]

Originally Posted by TruthSeeker1234

Mackey, you are simply incorrect about the floor trusses being the only cross-bracing for the core columns. Look here, for instance:

http://www.peaceproject.com/graphics...s/CA2-huge.jpg

(add needed h t t p and w's)


Please retract your error, or lose credibility.

You do know those corner columns that are cross-braced are the kangoo jacks supports and were dismantled when the job was complete right?

Most of the rest of the columns were straight braced against each other with some cross-bracing.

If you look at the framing plan and model NIST used you'll see they had the proper bracing in place.

[R.Mackey]

Originally Posted by TruthSeeker1234

Mackey, of course pictures of the core are during construction. How could we photograph it after they were finsished? Come on. There is ample photographic evidence that the 47 core columns were horizontally and diagonally braced. Where is your evidence that they were not?

Nope. Please answer my questions. Awfully hard to do the calculation without that information.

Originally Posted by TruthSeeker1234

Next, there was about 100,000 tons of concrete per tower, which is about equal to the mass of the steel. Regardless, It appears almost everything besides the steel was rendered into fine powder. Otherwise, where is it?

The total mass per tower is about 500,000 tons. It most certainly does not appear that "everything besides the steel" was rendered into 100 micron powder. If you have evidence for this, present it. Otherwise you're wasting all of our time.

Originally Posted by TruthSeeker1234

Still waiting for the pictures of stacked up floors, or desks, or . . .anything.

I don't deal in pictures. If you have something to say about my criticisms, please say it.

Originally Posted by TruthSeeker1234

Someone else upthread was wondering how much explosives it would take to bring the tower down, speculating it would take a nuke. Bear in mind that, using NIST logic, it would not take very much at all. NIST would have it that all that is needed is to initiate local collapse on one floor, gravity would do all the rest. Right?

Greening's work suggests that this is correct. But it's irrelevant, since there is no sign of explosives either before, during, or after the event.

ETA: I might add that a quick calculation of the gravitational energy reveals that each tower contained the equivalent of 0.16 kilotons of gravitational potential -- far, far more than chemical explosives could provide under any faintly rational scenario. If that's not enough energy for you, you need to bring many truckloads of high explosive to make a significant difference.

Originally Posted by TruthSeeker1234

Greening did point out what he felt were errors in Ross, which is why I linked his paper. Ross answered that even if Greening was right, it would only delay the halt of collapse by a fraction of a second.

Which is true, except all of the structural members would have failed before that half-second could elapse. Ross requires 3 meters of linear deformation in ALL of the columns, in addition to energy absorption that already takes them to their plastic limits, and on top of that removes two floors worth of crushing energy that wouldn't have happened until later. Ross's answer is quite silly. That's all outlined in my critique of his rebuttal.

[apathoid]

Truthseeker, have you any idea how much explosives would be necessary to micronize 50% of the floor slabs? Have you any idea why said explosives were so quiet? Did you know that in CD, the explosives are used to cut columns, not blow the floor slabs to smithereens?

[TruthSeeker1234]

Still waiting for any evidence of any significant macroscopic objects at ground zero, apart from steel. I think 50% dissociation is generous. More like 99% of the non-metallic mass was pulverized.

Mackey, I will study your critique of Ross. On first read, I got to the false statement about the floor trusses and stopped.

[apathoid]

Originally Posted by TruthSeeker1234

Still waiting for any evidence of any significant macroscopic objects at ground zero, apart from steel. I think 50% dissociation is generous. More like 99% of the non-metallic mass was pulverized.

Mackey, I will study your critique of Ross. On first read, I got to the false statement about the floor trusses and stopped.

Truthseeker, have you any idea how much explosives would be necessary to micronize 99% of the floor slabs? Have you any idea why said explosives were so quiet? Did you know that in CD, the explosives are used to cut columns, not blow the floor slabs to smithereens?

[R.Mackey]

Originally Posted by TruthSeeker1234

Still waiting for any evidence of any significant macroscopic objects at ground zero, apart from steel. I think 50% dissociation is generous. More like 99% of the non-metallic mass was pulverized.

Mackey, I will study your critique of Ross. On first read, I got to the false statement about the floor trusses and stopped.

Given that you've already made several serious errors in your first seven posts, I'm not interested in your guesses. Show me that 99% was pulverized, and show me the average fragment size by species. Until then, you're whistling Dixie.

You have yet to demonstrate my statement is false. You also have yet to demonstrate that you understand the point it makes.

[Pardalis]

Truthseeker, are you Terrocell on the LC forum by any chance?

[kevin]

does truthseeker1234 remind anyone else of christophera? Only wants pictures. Pulverization/atomization of concrete. Massive core (I'm just waiting for the claim it was concrete 7 floors below that picture.)

[TruthSeeker1234]

kevin wondered

Quote:

What weighs more 100lb of concrete or 100lb of concrete power 100 micron average diameter?

The mass is the same, the "weight", in the real world, would actually depend on a few things. Surface area to mass ratio, for instance. The bigger that ratio, the more air will resist it from falling.

If the implication is that puverized mass will push down on intact structure as well as non-pulverized mass, you must consider that the majority of the mass in each twin tower lander well outside the footprint of the building, thus making it unavailable to push down on the intact structure.

[David Wong]

Originally Posted by apathoid

Truthseeker, have you any idea how much explosives would be necessary to micronize 99% of the floor slabs?

Guys... I don't think he's talking about Controlled Demolition. I seriously think he's saying the buildings were empty mock-ups. I think that's why he's harping on the lack of furniture in the rubble.

After all, is there ANY method ever devised by mankind that could micronize 99% of a building's non-metal mass? Why would you want to?

[kevin]

Originally Posted by TruthSeeker1234

kevin wondered

The mass is the same, the "weight", in the real world, would actually depend on a few things. Surface area to mass ratio, for instance. The bigger that ratio, the more air will resist it from falling.

I said a 100 pounds vs. 100 pounds. That is already weight. And the conversion of mass to weight does not in anyway involve the surface area to mass ratio.

Quote:

If the implication is that puverized mass will push down on intact structure as well as non-pulverized mass, you must consider that the majority of the mass in each twin tower lander well outside the footprint of the building, thus making it unavailable to push down on the intact structure.

Says who? With what calculations?

[R.Mackey]

Originally Posted by TruthSeeker1234

If the implication is that puverized mass will push down on intact structure as well as non-pulverized mass, you must consider that the majority of the mass in each twin tower lander well outside the footprint of the building, thus making it unavailable to push down on the intact structure.

I just got done correcting einsteen about this in another thread.

There is some fractured mass, even some big chunks, that spills over the sides early. However, most mass that eventually lands outside the footprint gets there by first smashing into the structure, so it does contribute.

This is irrelevant vis-a-vis Ross's paper, since he is considering collapse initiation. There are no large chunks or small chunks to fall away at that time. Once the upper mass has a few floor's worth of momentum, collapse is inevitable even if a significant fraction of it ricochets off to the sides.

Please provide evidence for how much mass was ejected. And keep in mind that the debris pile after collapse would itself spill over the footprint, so a single post-collapse picture is not precise enough.

[stateofgrace]

Truthseeker1234 are you Gordon?

If you are,did you do as I suggested? Did you get your work reviewed by the bodies I suggested ?

[R.Mackey]

I don't believe this is Gordon Ross. He is not sufficiently familiar with Ross's papers.

[Gravy]

Originally Posted by TruthSeeker1234

Many observes at ground zero, such as governor Pataki, commented on the near-complete absence of macro-concrete in the rubble, and the presence of powder "from river to river".

AFAIK, no analysis was done of how much concrete was reduced to what size. George Pataki, who works in Albany, did not spend significant time down in the rubble pile.

Now, there was about 60,000,000 pounds of gypsum drywall in the towers. (at 19% sulfur content, that's 11.4 million pounds of sulfur...something smells like rotten eggs, Steven Jones). What do you think happened to it? Which do you think pulverized faster and finer, the concrete or the drywall? How about the 6,000,000 pounds of ceiling tiles and the millions of pounds of fire insulation? Which pulverized faster and finer those or the concrete?

Quote:

I observe very dense clouds of powder falling very fast to the ground, and swelling out into rapidly progressing pyroclastic flows quickly became 3-4 times the volume of the intact tower.

Please do some research on what a pyroclastic flow is. Hint: "Pyro."

Quote:

It certainly appears that entire towers were rendered almost totally into fine powder.

No, it doesn't, and you'll learn that arguing from incredulity ("It couldn't happen because I don't believe it could happen") is dealt with swiftly and savagely by the JREF ninjas here.

Quote:

If not, where did the concrete go? Where is the carpet? The computers? The pictures? Why was the biggest piece of non-metal that a rescue worker saw only "a half a keypad"?

Most went down, some went out. Here's a question: if most everything turned to dust, what comprised the 1.6 billion pounds of debris that was meticulously sorted on conveyor belts for evidence and remains at Fresh Kills landfill?

Here's a related post of mine, with a report from someone who did spend months in the pile, on what the rubble looked like to him: http://forums.randi.org/showpost.php...1&postcount=20

Quote:

Can someone link us to some photographic evidence of some stacked up concrete floors?

I apologize for not having the link to this handy. Maybe someone can remember where it came from. IIRC, this museum display shows 8 tower floors compacted to four feet high.