Why a one-way Crush down is not possible

[Oscar]

Twin:

Jesus. If the "official story" was as full of holes as you folks claim it is, and the science is SO good that the collapse as described was impossible, you should have real experts, main-stream media, and law enforcement people coming out of the woodwork supporting you.

Until then you can gesticulate wildly as much as you want.

Hear hear. Or here here.

Whatever the correct term is I agree wholeheartedly.

 

[Heiwa]

Prior to collapse, all the column-to-truss connections had 5 linear and 3 moment constraints. The top & bottom splice had 2 linear and 3 moment constraints.

After the start of collapse, the top of the column has lost all constraints. The other locations have variable constraints remaining, as listed.

Note that this constraints table tallies all the constraints for 9 side-by-side columns. All the missing columns have lost all constraints, of course.

The end result of losing all of these constraints is that the columns are far, far less capable of supporting loads than they were prior to the collapse initiation.

In other words, Heiwa's reference to "Part A columns, undamaged, between Floors 97 and 99" is utter, unmitigated nonsense.

Tom

I thought I suggested that all part A columns below, say floor 97, were undamaged prior part C impacting part A, but it could also be floor 96.

The perimeter columns consisted of welded assemblies of three columns and three spandrels (abt 11 x 3 m big - three floors) and then these assemblies were simply bolted together at the joints; four bolts between columns, eight bolts between spandrels. Thus about 20 assemblies each side and 4 in the corners. So 84 assemblies of bolted perimeter columns formed a square (side 60 m - the outer tube) around the core; the latter was of different design - 46 columns and many beams welded and rivetted together. The floors were then just hanging/bolted on the columns between core and perimeter.

If an upper part C was disconnected from the structure and dropped down on part A below, plenty of columns had to fail in between, say floors 97-98 or 96-99. Completely unrealistic, but let's assume it. Thus then part C is displacing down and contacting A.

Let's look at the outer tube! How can a square ring of perimeter assemblies in part C, side 60 m, contact the same ring in part A? Are the two rings aligned or off set a little. Probably the latter and in that case two C sides contact nothing and the other two sides contact an A floor, 96 or 97 at your choice.

Similar happens to the four A sides! Two A sides are outside part C and two A sides contact a C floor, say it is floor 98.

The contact is thus unsymmetric and the local failures that would follow, if such a collision took place, are also unsymmetric. One thing is sure. The lowest part C floor is going to get locally damaged by some A columns.

And that's the start of part A arresting part C in its decent.

It's like chess. White attacking the king's side and Black the queen's side.

 

[bill smith]

This is the official government position regarding the demolitions of the Twin Towers and Building seven. Somebody should write up a motivated tebuttal to most oftheir reasoning. It's sure nice to have it under their signature as of may 5th 2009.

'' Numerous unfounded conspiracy theories about the September 11 attacks continue to circulate, especially on the Internet. Some of the most popular myths are:

1) The World Trade Center (WTC) twin towers were destroyed by controlled demolitions.

This is how the collapses may have appeared to non-experts, but demolition experts point out many differences:

• Demolition professionals always blow the bottom floors of a structure first, but the WTC tower collapses began at the upper levels, where the planes hit the buildings.

• Non-experts claim that debris seen blowing out of windows was evidence of explosive charges, but experts identify this as air and light office contents (paper, pulverized concrete, etc.) being forced out of windows as floors collapsed on each other.

• Demolition firms had very sensitive seismographs operating at other sites in Manhattan on September 11. None recorded signs of any explosions prior to the tower collapses. Instead, seismic spikes were noted when debris began hitting the ground.

• Cutting away walls, insulation, plumbing, and electrical conduits to place numerous charges on the towers’ structural columns in advance would not have gone unnoticed.

• Clean-up crews found none of the telltale signs of controlled demolitions that would have existed if explosive charges had been used.

• For more information, see ImplosionWorld’s article (PDF, 56 K) on the WTC collapses, the March 2005 Popular Mechanics, parts 4 and 5, “The Attack on the World Trade Center Towers,” and the video 9/11 Debunked: Controlled Demolition Not Possible.''
http://www.america.gov/st/webchat-english/2009/May/20060828133846esnamfuaK0.2676355.html

 

[aggle-rithm]

This is the official government position regarding the demolitions of the Twin Towers and Building seven.

...snip...

• For more information, see ImplosionWorld’s article (PDF, 56 K) on the WTC collapses, the March 2005 Popular Mechanics, parts 4 and 5, “The Attack on the World Trade Center Towers,” and the video 9/11 Debunked: Controlled Demolition Not Possible.''
http://www.america.gov/st/webchat-english/2009/May/20060828133846esnamfuaK0.2676355.html

Implosion World and Popular Mechanics are part of the US government?

 

[twinstead]

Implosion World and Popular Mechanics are part of the US government?

Of course they are. Any group or individual who disagrees with the truthers is "part of the US government".

 

[ElMondoHummus]

.
Steve,

What is your profession?

There are perhaps 30 different professions that have a role in the events of 9/11. Structural engineering, computer modeling, corrosion, aviation, etc.

Mine is mechanical engineering.

Even tho I post here and one other 9/11 thread, I haven't come out to anyone and said "NIST is right". Even tho I believe that to be the case. (To the 98th percentile.) Because the things that I think that they got wrong are trivial and inconsequential to their conclusions.

But if I found something that violated some mechanical engineering principle (say they said the steel lost strength at 150°C), you can bet your ass that I'd point it out. Loudly. And there would be no ignoring it on the part of NIST. Because every mechanical engineer in the country would be demading an explanation just as vocally.

So, in that respect, I believe that it IS valid to say that, in a case that is SO momentous, silence does indicate assent.

It certainly does in my case.

Tom

Tom is probably already aware of this, but for non-participating readers, there is information unsaid that might escape you if you haven't been keeping up to date on the myth peddling by the "Truth" movement. And it is this: As far as the engineering, building safety, fire engineering, and architectural professions are concerned, there is actually zero silence on the issue of the NIST report's veracity. As I and others have pointed out before, the ICC has not only accepted NISTs findings, but is already in process of integrating that knowledge into future building codes. Some of the findings - for example, the issue of fireproofing bonding, as well as an increase in the fire resistance rating of structural components and assemblies - directly address issues highlighted in the NIST report. Other changes are still being studied. But my point is that, while Tom is 100% correct about individuals not speaking up and signing petitions, creating groups, etc. regarding their acceptance of the NIST report, there's context here that someone who hasn't studied 9/11 might be missing, and that's that their professional bodies have indeed sounded off on the issue. And they unquestioningly accept NISTs findings. The ICC modifications to code prove that. And buildings built to codes developed with that knowledge, like the Beijing Mandarin (which by the way burnt down back in February), are further proof.

The bottom line is that there is indeed widespread acceptance of the NIST report. And it's not just rhetorical, it's actually practical acceptance.

 

[SteveAustin]

You've been caught lying again. I most certainly did not "backtrack" on anything. I slammed my claim across your face like a dead flounder and you had nothing in reply.
We're still waiting for you frauds to produce a single demolition expert who thinks the towers were demolished. You can't, "truther"--there are none.

Tell us why every demolition expert in the world rejects the idiocy you peddle.

Many demolition experts have pointed out that your insane movement's myths about explosives in the towers are completely absurd

So you go from "every demolition expert in the world" to "many". You lurkers notice how "truthers" are always being called liars even when the proof we were telling the truth is right there in front of your face. You see you are not supposed to scroll back up and look, you are simply supposed to believe what he says.

Now it seems like you are jumping back to "every". Can't make up your mind?

Someone listed 1 demolition expert that endorses the Official Conspiracy Theory, you have any others? I mean 1 is still a far cry from "every demolition expert in the world".

YOU MADE THE CLAIM, YOU NEED TO BACK IT UP

 

[tfk]

I thought I suggested that all part A columns below, say floor 97, were undamaged prior part C impacting part A, but it could also be floor 96.

Since you seem to suffer from a raging case of ADD, let's take one thing at a time.

You seem to be getting a glimmer of the real picture with this statement. Do you agree with the damage assessment to the columns, floors and cross trusses of the 97th & 96th, as I have described it, when the THREE STORY HIGH 98th floor column assemblies buckle or pop free (i.e., connections fail)?

I agree with you that similar (virtually symmetrical) damage will get done to 99th & 100th floors of the upper Part C.

Answer this please, and then I will address the rest of your question.

Tom

 

[aggle-rithm]

So you go from "every demolition expert in the world" to "many". You lurkers notice how "truthers" are always being called liars even when the proof we were telling the truth is right there in front of your face. You see you are not supposed to scroll back up and look, you are simply supposed to believe what he says.

Now it seems like you are jumping back to "every". Can't make up your mind?

Someone listed 1 demolition expert that endorses the Official Conspiracy Theory, you have any others? I mean 1 is still a far cry from "every demolition expert in the world".

YOU MADE THE CLAIM, YOU NEED TO BACK IT UP

You're arguing semantics again.

Do you have ANY evidence of this controlled demolition you so desperately want to believe in?

 

[tfk]

Tom is probably already aware of this, but for non-participating readers, there is information unsaid that might escape you if you haven't been keeping up to date on the myth peddling by the "Truth" movement. And it is this: As far as the engineering, building safety, fire engineering, and architectural professions are concerned, there is actually zero silence on the issue of the NIST report's veracity. As I and others have pointed out before, the ICC has not only accepted NISTs findings, but is already in process of integrating that knowledge into future building codes. Some of the findings - for example, the issue of fireproofing bonding, as well as an increase in the fire resistance rating of structural components and assemblies - directly address issues highlighted in the NIST report. Other changes are still being studied. But my point is that, while Tom is 100% correct about individuals not speaking up and signing petitions, creating groups, etc. regarding their acceptance of the NIST report, there's context here that someone who hasn't studied 9/11 might be missing, and that's that their professional bodies have indeed sounded off on the issue. And they unquestioningly accept NISTs findings. The ICC modifications to code prove that. And buildings built to codes developed with that knowledge, like the Beijing Mandarin (which by the way burnt down back in February), are further proof.

The bottom line is that there is indeed widespread acceptance of the NIST report. And it's not just rhetorical, it's actually practical acceptance.

EMH,

Nice catch.

I wouldn't want readers to be mislead, and as EMH points out, there is a huge, on-the-record consensus amongst the impacted fields that NIST got it right.

And that design procedures need to be adjusted to consider what was an unanticipated failure mode (the WTC7 collapse mechanism) and several changes (i.e., better thermal protection & more robust stairwells) for towers-type design.

I have not heard a single competent engineering group that has come up with a serious hole in the NIST report. The closest is Dr. Quintierre, who believes that the trusses played a larger role than NIST attributes to them.

And no competent engineers feel the need to invoke explosives to explain any of those buildings' collapses.

In my reply to SteveAustin, I was discussing only those engineers who have not published their agreement "on the record".

Tom

 

[SteveAustin]

You are wrong. (You are a "truther"--you are ALWAYS wrong.)

I hope everyone is paying attention, because this is the attitude from the vast majority of "debunkers" here. They are so convinced that "truthers" are ALWAYS wrong that they will always claim "truthers" are wrong no matter what.

This attitude. This stance does not allow for free debate, how can you debate with someone who comes into the debate saying you are wrong and you are always wrong.

They don't care about evidence, or facts, or science... "truthers are wrong and they are always wrong" is enough for them.

When claims are being made by a representative member of a group, as the Loizeaux family is unquestionably representative of the demolition industry, the claims stand unless challenged.

That is completely different than what you said up above, here let's get those 2 statements together so everyone can see it plainly...

The absence of any voiced disagreement by demolition professionals indicates a consensus.

When claims are being made by a representative member of a group, as the Loizeaux family is unquestionably representative of the demolition industry, the claims stand unless challenged.

You see, they are not the same thing. You are having a very difficult time trying to defend your absurd statement that an absence of voiced disagreement indicates consensus.

Why do you "debunkers" have to always be right at all costs even when it's so obvious you are wrong? I know, because that would allow that crack to appear and cast doubt in the eyes of some, and you cannot have anyone think you could be wrong about anything right? Problem for you is your tactic backfires, your defiant refusal to admit the obvious here shows people that if you do it for this obvious one then what else are you defiantly refusing to admit that might not be so obvious to some!!!

Nobody who works in demolition swallows the snake oil your insane movement peddles. There isn't demolition expert alive who thinks it would have feasible to smuggle tons of charges into the towers and then place them without anyone noticing. That you can't see your claims for the idiocy they are says something about you, not about sane people who don't share your problem.

Everyone again notice the constant slurs and insults? It's all part of the tactics, smear your opponent at every turn (this has the effect of scaring people off...usually subliminally...scaring people away from the topics and by default accepting the Official Conspiracy Theory, because most people are afraid to be labelled in this fashion)

OK so you again make a claim that you could not know is true. Tell me finewine, what is this the 5th time I ask you to provide proof of your claims here (not to mention deep44's and Bill's as well), are you ever going to prove that "every demolition expert in the world" endorses the Official Conspiracy Theory? Or are you simply going to repeat your statement like a mantra and hope that people will buy it?

 

[SteveAustin]

...

Hey newton, what was my original goal post that you claim I moved?

 

[bill smith]

Since you seem to suffer from a raging case of ADD, let's take one thing at a time.

You seem to be getting a glimmer of the real picture with this statement. Do you agree with the damage assessment to the columns, floors and cross trusses of the 97th & 96th, as I have described it, when the THREE STORY HIGH 98th floor column assemblies buckle or pop free (i.e., connections fail)?

I agree with you that similar (virtually symmetrical) damage will get done to 99th & 100th floors of the upper Part C.



Answer this please, and then I will address the rest of your question.

Tom

Part C fell directly down on part A. The only force on the upstanding giant core columns was therefore compressive. After a small amount of elastic absorence of the downward force these columns would have punctured any floor and stripped off any floor to column connection that they met. This would have ocurred before any plastic deformation of the upstanding columns was spossible seeing that the PE of the seperate descending components could never have overcome the general SE of the individual upstanding giant columns.

Furthermore as the upstanding columns buried themselves deeper in the descending body of part C that body would have provided lateral support for the upstanding columns.

 

[SteveAustin]

It's his argument that the collapses were CD. It is his responsibility to find evidence to support it. That would include finding some CD experts who agree with him, no?

Personally, I'm not making a claim. I'm not saying that the majority of CD experts agree with the 'official story'. The ones who have come out, implosionworld for example, are enough for me. Let's imagine for a moment that NO cd expert has come out one way or the other. What would YOU do to gather evidence for CD?

You guys are all very good at that little game. I have made no claim, I have asked finewine to prove HIS claim.

So NO, it is not MY argument. Nice try to deflect this back onto me however. Maybe next time it will even work.

BTW, you might want to talk to your buddy finewine and get him to realize what his 2 claims really are.

 

[tfk]

So you go from "every demolition expert in the world" to "many". You lurkers notice how "truthers" are always being called liars even when the proof we were telling the truth is right there in front of your face. You see you are not supposed to scroll back up and look, you are simply supposed to believe what he says.

Now it seems like you are jumping back to "every". Can't make up your mind?

Someone listed 1 demolition expert that endorses the Official Conspiracy Theory, you have any others? I mean 1 is still a far cry from "every demolition expert in the world".

YOU MADE THE CLAIM, YOU NEED TO BACK IT UP

.
So, let me see if I have this straight.

Your case is built upon the "rock solid" foundation that:

"Every expert in the field does not disagree with me. It's only ALMOST every expert in the field who disagrees with me."

Ever heard the expression "damned by faint praise"??

Perhaps you'd better get back to arguing the specifics and stop sifting thru haystacks looking for that "alternative experts" needle.

Tom

 

[SteveAustin]

His beliefs have absolutely nothing to do with FineWine's claim about what every demolition expert in the world believes.

This really shouldn't be all that difficult to understand.

Deep44, they all understand it perfectly, but finewine got himself into a fine pickle and the only way everyone sees to get out of it is to dodge and weave and try and turn everything around onto us "truthers"

They do this ALL THE TIME.

Edit:

It isn't. It's clear that you're trying to avoid the issue by focusing on semantics.

See what I mean. That's a perfect example.

 

[SteveAustin]

.
Steve,

What is your profession?

There are perhaps 30 different professions that have a role in the events of 9/11. Structural engineering, computer modeling, corrosion, aviation, etc.

Mine is mechanical engineering.

Even tho I post here and one other 9/11 thread, I haven't come out to anyone and said "NIST is right". Even tho I believe that to be the case. (To the 98th percentile.) Because the things that I think that they got wrong are trivial and inconsequential to their conclusions.

But if I found something that violated some mechanical engineering principle (say they said the steel lost strength at 150°C), you can bet your ass that I'd point it out. Loudly. And there would be no ignoring it on the part of NIST. Because every mechanical engineer in the country would be demading an explanation just as vocally.

So, in that respect, I believe that it IS valid to say that, in a case that is SO momentous, silence does indicate assent.

It certainly does in my case.

Tom

That's a well written and thought out response, and it is utter nonsense. Your belief that it is valid does not make it valid, regardless of how momentous an event it is.

In this case you are simplifying a complex issue into what you believe people would do in a certain situation.

But it's nice to know you are another one who believes that an absence of voiced dissent means they consent. This can discredit your critical thinking or that is your lack thereof.

The more of you who speak up like this the more people will see how very many of you here have skewed beliefs

 

[Grizzly Bear]

But it's nice to know you are another one who believes that an absence of voiced dissent means they consent.

Active changes in building codes aren't valid indications?

 

[tfk]

Bill, please...

Part C fell driectly down on part A.

.
Close.

The only force on the upstanding giant core columns was therefore compressive.

.
No.

After a small amount of elastic absorence of the downward force these colmns would have punctured any floor and stripped off any floor to column connection that hey met.

.
Even after translating this into actual, you know, "English"... No.

This would have ocurred before any plastic deformation of the upstanding columns was spossible seeing that the PE of the seperate descending components could never have overcome the general SE of the individual upstanding giant columns.

.
No.

Furthermore as the upstanding columns buried themselves deeper in the descending body of part C that body would have provided lateral support for the upstanding columns.

.
No.

If I wanted this sort of a technical conversation this morning, I would have engaged the Chihuahua. Even tho yappy, he is far less annoying than you are.

You see, the Chihuahua doesn't possess delusions of technical competence.

tom

 

[Gamolon]

Let's look at the outer tube! How can a square ring of perimeter assemblies in part C, side 60 m, contact the same ring in part A? Are the two rings aligned or off set a little. Probably the latter and in that case two C sides contact nothing and the other two sides contact an A floor, 96 or 97 at your choice.

Similar happens to the four A sides! Two A sides are outside part C and two A sides contact a C floor, say it is floor 98.

The contact is thus unsymmetric and the local failures that would follow, if such a collision took place, are also unsymmetric. One thing is sure. The lowest part C floor is going to get locally damaged by some A columns.

And that's the start of part A arresting part C in its decent.

Another contradiction.

You say two walls of perimeter columns will contact the floor.

Can you please explain why you have this drawing of WTC1/WTC2 showing the perimeter columns SPEARING the concrete floors and breaking them into nice long slabs? Why do you not show what you have claimed above?

Please. Explain why you show the perimeter columns spearing the concrete floor andn then say that two walls of perimeter columns would collide with the floor below creating LOCAL failures.