Failure mode in WTC towers

[Tony Szamboti]

Your video was really not very good. What does the guy who made it do for a living. Fiction? You believe idiots who make up lies on video, but are unable to ask your own teachers or real expert how things work. Cool. You will leave this thread like you do the rest, not willing to learn on your own, or from others.
You left this one, and you know more about the rod warhead, than building mechanics.

The guy who made that video is a physics teacher by the name of David Chandler.

 

[beachnut]

The guy who made that video is a physics teacher by the name of David Chandler.

He is daft and deaf. Great, his work is like yours, full of errors and wrong.

 

[Tony Szamboti]

Fully-fueled commercial airliners slammed into the Twin Towers at high speeds. The impacts dislodged fireproofing and caused widespread fires that led to the inward bowing of external columns that everyone observes on the videos. Instead of the endless tap dancing, why doesn't your side explain why the buildings should NOT have collapsed?

I did that in a paper I wrote. Have you read it?

http://www.journalof911studies.com/...itionHypothesisForDestructionofTwinTowers.pdf

It does need to be updated now that we know the actual mass of the towers and the cross sections of the core columns thanks to Gregory Urich and Lon Waters.

The factor of safety is actually 3.00 to 1 for the central core and 5.00 to 1 for the perimeter wall when considering gravity loads only. I underestimate that in the earlier version of the paper due to having less information than we do now.

 

[Dave Rogers]

It does need to be updated now that we know the actual mass of the towers and the cross sections of the core columns thanks to Gregory Urich and Lon Waters.

It might be a good idea in the update to consider the actual observed failure mode as a possible failure mode. You missed that minor point in the original.

Dave

 

[Tony Szamboti]

It might be a good idea in the update to consider the actual observed failure mode as a possible failure mode. You missed that minor point in the original.

Dave

Dave, what I am saying in that paper is that I don't see how the observed failure mode could even occur without some form of demolition. There weren't enough columns destroyed and damaged for the factor of safety to be taken down low enough and there is no physical evidence for high enough steel temperatures to cause a collapse.

With the remaining factor of safety, after considering lost and damaged columns, all of the still viable remaining columns would have had to reach 650 degrees C (1202 degrees F) for collapse to even be possible. Those columns could not have gotten that hot and that is why there is no physical evidence for it.

 

[beachnut]

I did that in a paper I wrote. Have you read it?

http://www.journalof911studies.com/...itionHypothesisForDestructionofTwinTowers.pdf

It does need to be updated now that we know the actual mass of the towers and the cross sections of the core columns thanks to Gregory Urich and Lon Waters.

The factor of safety is actually 3.00 to 1 for the central core and 5.00 to 1 for the perimeter wall when considering gravity loads only. I underestimate that in the earlier version of the paper due to having less information than we do now.

Read it, I peer reviewed it and sent it back; you failed to make simple corrections; like this dumb error.

says the towers would survive the impact of a fully loaded Boeing 707-320B, with a
336,000 lb.max takeoff weight,4 moving at 600 MPH.

Here is a simple image of Robertson's design point, he was responsible for this design. Design point, match, game. Many errors, you can not correct one. You say 600, it was 180 mph, and that error is 14 times off in energy! How can anyone trust you, you can not even research the simple stuff.
.

Your paper has erroneous assumptions, like a 600 mph impact. No sources and hearsay junk in a paper? How can you present a flawed paper? Fix the errors, it makes your work useless.

 

[Tony Szamboti]

deleted

 

[Tony Szamboti]

Your paper has erroneous assumptions, like a 600 mph impact. No sources and hearsay junk in a paper? How can you present a flawed paper? Fix the errors, it makes your work useless.

I am going to start using your own language on you.

Your hypothesis simply stinks.

Can you even tell us how many columns were destroyed and heavily damaged in both towers?

 

[Myriad]

Thanks for trying to answer my questions. Your response largely consists of the Pancake progressive collapse type theory.

However, I think we can rule out Pancake collapse (as I believe NIST did even for "global collapse") for a number of reasons, several of which are captured in this picture of the South Tower:

[qimg]http://img262.imageshack.us/img262/2738/05mf8.jpg[/qimg]

You asked me to explain the phenomena in one segment of video, and then you tell me that that can't be what happened because things look different in another video. Is that the same walls of the same tower, at the same moments of the collapse? If not, why would you expect the exact same behavior? Is there some rule I didn't know about, that says that the dynamics of a tower collapse have to stay exactly the same from beginning to end?

But in any case, I don't see anything in the linked images or video that rules out pancaking collapse of floors, proceeding behind the (momentarily) still-standing perimeter columns. The ejections of dust out the window spaces are clearly irregular, appearing at some floors (and at some points along the edge of some floors) and not others, perhaps depending on what edge of the floor space is leading the internal collapse moment by moment, or on how much dust-generating drywall is installed on each floor.

NIST ruled out pancaking of floors as the mechanism for collapse initiation. In other words, they concluded that no floors pancaked before global collapse began. But once collapse is underway, floors have to impact on floors. There's nowhere else for them to go. They can't tilt sideways and plunge down edge-first, there's no room. They didn't float sideways out the sides like a stack of frisbees. They didn't fold up into giant origami penguins. They fell down. And the next floor down is right there waiting for them. How is an acre-sized floor going to miss another acre-sized floor twelve feet below it? Of course they're going to pancake. The only question is how evenly; that is, how much other debris gets in the way, what size fragments they break into and how much those fragments get churned up in the debris mass instead of staying in layers. But by the time that's an issue (long before you can say "clunkity-clunk") the next impact with the next floor down has already happened and it no longer matters.

Respectfully,
Myriad

 

[Dave Rogers]

Dave, what I am saying in that paper is that I don't see how the observed failure mode could even occur without some form of demolition. There weren't enough columns destroyed and damaged for the factor of safety to be taken down low enough and there is no physical evidence for high enough steel temperatures to cause a collapse.

With the remaining factor of safety, after considering lost and damaged columns, all of the still viable remaining columns would have had to reach 650 degrees C (1202 degrees F) for collapse to even be possible. Those columns could not have gotten that hot and that is why there is no physical evidence for it.

You're still not considering the actual failure mode. I suggest you re-read the NIST report. I assume you've studied it in considerable detail but that you've just forgotten everything about how the collapse initiated, because I'm sure you wouldn't be foolish enough to have written a paper on the WTC collapses without consulting the most thorough analysis of the subject in existence, but you're clearly not aware of its conclusions on failure mode because your post is not taking them into account.

Dave

 

[Tony Szamboti]

You're still not considering the actual failure mode. I suggest you re-read the NIST report. I assume you've studied it in considerable detail but that you've just forgotten everything about how the collapse initiated, because I'm sure you wouldn't be foolish enough to have written a paper on the WTC collapses without consulting the most thorough analysis of the subject in existence, but you're clearly not aware of its conclusions on failure mode because your post is not taking them into account.

Dave

Do you mean the alleged sagging floor trusses and viscoplastic creep of the core columns pulling on the perimeter columns and causing them to buckle?

 

[Myriad]

I did that in a paper I wrote. Have you read it?

http://www.journalof911studies.com/...itionHypothesisForDestructionofTwinTowers.pdf

It does need to be updated now that we know the actual mass of the towers and the cross sections of the core columns thanks to Gregory Urich and Lon Waters.

The factor of safety is actually 3.00 to 1 for the central core and 5.00 to 1 for the perimeter wall when considering gravity loads only. I underestimate that in the earlier version of the paper due to having less information than we do now.

Even accepting your safety factors as correct (which is disputed by other qualified experts, so I don't recommend anyone else do so), these factors are meaningless unless the load is evenly distributed, as designed, among the columns.

After the airplane collision damage, that was no longer the case. So the averages you calculated, even if they're correct, mean nothing.

I can't hold a 300 Kg barbell overhead, just because I have eight friends who are empty-handed making the average load 33-1/3 Kg with a safety factor of 3.00 to 1. (I can manage a 100 Kg barbell safely.) That illusory safety factor will not make the barbell any lighter. Reality will prevail over useless calculations based on bad models.

Respectfully,
Myriad

 

[Dave Rogers]

Do you mean the alleged sagging floor trusses and viscoplastic creep of the core columns pulling on the perimeter columns and causing them to buckle?

That's the one. Note that the buckling was observed, so if you can't explain that either, it's your understanding that's faulty, not the failure mode.

Dave

 

[beachnut]

I am going to start using your own language on you.

Your hypothesis simply stinks.

Can you even tell us how many columns were destroyed and heavily damaged in both towers?

Your errors are factual errors, not a theory of mine. You include hearsay, and fail to have proper sources. Robertson said your numbers are wrong on the impact on the design of the WTC. So with an impact of 7 to 11 times in KE than the design, Roberson is correct in saying his design was exemplary since it was only design to withstand an impact 7 to 11 times smaller in KE. Sorry this is just one of your major errors in a paper clearly motivated with bias. Your paper does not even mention the maximum load a floor can hold. Totally misleading.

You can say my hypothesis stinks, but it is not a theory, it is a fact you have misstated the impact design done on the WTC. If you can not get the design correct, you model is incorrect. Not a theory, just a fact.

It will only get worse if you persist at pretending to be a structural engineer who can understand anything to do with the WTC failure modes. People will pick you paper apart as you fail leaves out possible failure modes a grade school kid can identify.

 

[Tony Szamboti]

Even accepting your safety factors as correct (which is disputed by other qualified experts, so I don't recommend anyone else do so), these factors are meaningless unless the load is evenly distributed, as designed, among the columns.

After the airplane collision damage, that was no longer the case. So the averages you calculated, even if they're correct, mean nothing.

I can't hold a 300 Kg barbell overhead, just because I have eight friends who are empty-handed making the average load 33-1/3 Kg with a safety factor of 3.00 to 1. (I can manage a 100 Kg barbell safely.) That illusory safety factor will not make the barbell any lighter. Reality will prevail over useless calculations based on bad models.

Respectfully,
Myriad

I think you are exaggerating the eccentricity and overloading of individual columns. The beams would have caused the loads to bridge just as you saw on the perimeter where the spandrels did that job. Do you think the load of the 35 missing perimeter columns was applied to just the columns on either side of the gash? There were only 20% maximum of the core columns destroyed and or heavily damaged and they were somewhat interspersed at least in the North Tower. In fact, the collapse in the North Tower began on the 98th floor which had lost almost no columns.

I am curious as to who these other experts are that you refer to concerning calculation of the safety factors. Where can I find their work?

 

[Tony Szamboti]

That's the one. Note that the buckling was observed, so if you can't explain that either, it's your understanding that's faulty, not the failure mode.

Dave

I fully discussed NIST's hypothesized initiation mechanism, due to alleged floor and core column sagging, in the paper, and I provide an alternate explanation for the observed perimeter column bowing and buckling.

 

[Max Photon]

Tony, could I trouble you to restate your alternative model for the observed perimeter column bowing and buckling?

(Very short is fine.)

 

[beachnut]

Tony, could I trouble you to restate your alternative model for the observed perimeter column bowing and buckling?

(Very short is fine.)

Read his paper http://www.journalof911studies.com/...itionHypothesisForDestructionofTwinTowers.pdf

His paper is the most scientific paper you will find. Look at this power packed scientific discovery of facts to support his realcddeal. This one section proves the columns were in another country!~? duh

One may wonder who would want people in Afghanistan and Iraq to be blamed if they didn’t do it. A good hard look at the soon to be built U.S. oil company controlled gas and oil pipeline in Afghanistan, and the privatization of Iraq’s oilfields to U.S. oil companies, might be a start at solving that puzzle for oneself. Neither of these situations would have been possible, without the support of the American people, for the use of the U.S. military, to overthrow the previous governments of these countries.

realcddeal why is this in your paper? Is this a political piece? I was wrong, it may be an OpEd.

But read his paper, it is really not a real peer reviewed work, because that last section would not be in real scientific paper. Maybe a NAZI like paper, but not the free world. Or am I wrong, does political tripe make a paper more scientific. Or does it point to serous problems? I have tried to find something, but as of yet, no real information from this paper supports the realcddeal failed conclusions. I will read it again. And see if there are any facts to support this thread. The more I read the more errors I find. I do not know what to call the passage I included. Is that an error, or just stupid filler?

 

[Max Photon]

Sometimes a simple smile...

ThankyouBeachnutforthatinformativeupliftingpiece

I really was just looking for a simple sentence or two to juxatpose with:

Fires heated unprotected floor trusses and perimeter columns, causing floors to sag and pull perimeter columns inward.

 

[beachnut]

Thankyou Beachnut for that informative, uplifting piece.

I really was just looking for a simple sentence or two to juxatpose with:

Fires heated unprotected floor trusses and perimeter columns, causing floors to sag and pull perimeter columns inward.

http://www.journalof911studies.com/...itionHypothesisForDestructionofTwinTowers.pdf
Read his paper, and see if you agree he has what he said he has. It is not a long paper. You may find some errors you can help him with. Tony is a realcddeal, so thermite is up his alley.