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WTC7 and the girder walk-off between column 79 and 44

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Originally Posted by gerrycan
Depends, how hot did it get? And NIST say that these beams were heated uniformly in their analysis, so their expansion would be proportional to their length. I know it's a crazy idea to think that these beams could all go to 600 deg in a few seconds and uniformly at that, but hey, that's NIST for ya.


Citation needed.
NIST heated the entire area to 500oC [girder] and 600oC [beams] in 1.5 seconds.

NCSTAR 1-9 Vol.1 pg 352 [pdf pg 396]
Ramping of the temperatures for the beams and the girder then commenced at 1.1 s, as shown in Figure 8–25, leveling off at temperatures of 500 °C for the girder and 600 °C for the beams at 2.6 s.

ETA: This was in the preliminary "rock off"analysis where the beams buckled.

So why didn't the beams buckle when heated to 610oC* in the final analysis? They can't have it both ways.

*The temperature required to make them expand 5.5" and pushed the girder off its seat - if it were 11" wide.
 
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No, the 11" was what NIST said in the final report. The 1' 0" was what was on the drawing that NIST got its information from.

That is not an innocent mistake IMnsHO.

So, if it was 1' wide the building wouldn't have fallen on it's own?
 
Gerrycan,

We researched and produced the videos mentioned in this thread at the beginning. We will happily debate anyone who feels so compelled, real time, in an open forum, providing they are genuinley trying to get to the truth about this. There is more than just a 12" seat under this girder, even if it were possible, the girder would have to walk way more than 6" to get to a point where the bottom of it were unsupported, and also there has been no mention of the sideplates, which NIST also failed to take into account in their analysis. Further,look again at plate 'pg' it is underneath the 12" 'pf' plate and increases the required walk off almost by a factor of 2. I could go on and on......and maybe i will.


Please provide a little bit of information, and then I'll debate you calmly.

How many people are in your group that produced these videos?

Please provide the following:
Person 1 has been a [profession] for [xx] years.
Person 2 has been a [profession] for [xx] years.

Person n has been a [profession] for [xx] years.

I'd just like to know the level of expertise (especially in structural or mechanical engineering) that I'm dealing with.
___

You say that you have been unsuccessful at being able to get a response from NIST, even tho you have tried several times.

Could you please post a sample of one of your typical communications to them. I'd like to get a sense of the tone of the inquiry.

You know, where it resides on the scale of "we have some questions for which we'd respectfully request some elaboration" to "who paid you off to falsify your report?"

You do realize, I assume, that if you ask exactly the same question that they've been asked by the "who are you lying for" crowd, they are smart enough to figure out who you are.

Tell me something, if you had devoted several years of your life, contributing your considerable expertise to the US in its time of need, probably getting about 20% of the compensation that you'd normally get, and a bunch of know-nothing punks publicly & repeatedly accused you of being bought & paid for, accessories after the fact to mass murder & treason, all because they are snot-nosed wet-behind-the-ears punks who haven't the slightest clue what they are yammering about, would you feel "positively inclined to help them part the clouds of their ignorance"?

How about if you had tried to do exactly this, say, 50 times, only to be met with derision and determined stupidity & a complete unwillingness to learn anything. Would you continue to beat your head against that pathetic wall?

Or would you simply say "enough", & ignore the morons?

You'll excuse me, of course. I'm "just asking questions".
___

Are you the narrator for those videos? Is your group centered in the UK, or spread about?

I assume that you are members of ae911t?

You'll get no help from ae911t architects or engineers, of course. Architects don't understand the issues. They don't do stress analysis equations, especially on damaged buildings. And the ae911t engineers … well, they've successfully passed a very effective filtering process that demonstrates them to be in the bottom 1% of the profession.

Sad, but true.

But there are hundreds of independent, unbiased structural engineers in your neck of the woods. Pretty much no matter where you live. They work in industry & academia.

If you got rid or the insulting accusatorial tone, and the ludicrous "I've never taken an engineering class in my life, but I'm certain that these career Professional Engineers are wrong" attitude, and approached one or more of these guys with your questions, I'm certain that you'd find one to help you out.

As long a the 'tude stayed in check, of course.

Why haven't you tried this?


tomk

PS. Your posting history is, shall I say, "curious".

Before yesterday (@2:44 with post #164 in this thread, you had posted exactly 8 times on a total of 3 days.

1 post on Mar 2, 2012.
1 post on Oct 4th, 2011
6 posts on Aug. 24, 2010.

When you started posting yesterday, you replied to a post of mine to Christopher7, and have since produced a fusillade of 36 posts in 1.5 days.

That's a pretty remarkable change in behavior.

Two additional questions come to mind:
1. Is Chris7 one of the members of your group?
2. Did Chris7 ask you to come here & start posting?
 
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C7,

Now that you're back, I am certain that you were just about to reply to the post that I addresses to you before Gerrycan started his blitzkrieg.

It's buried fully half-way back in the thread. Post #163.

I'll save you the trouble of having to chase it down, and just quote it here:

tfk said:
OK, so we have a difference in interpretation of the report.

You claim that "walk off" is a specific term that means the W33 girder sliding (you say 6") to the west until the girder central web is aligned with the west end of the seat & then rotating CW (looking from N to S at the side of W33 girder) & dropping.

Correct?

I say that "walk off" is a generic term for the girder falling off of the seat (in any manner), which specifically includes all the details that are described in the detailed FEA analysis of section 8.8.

In other words, my definition of "walk off" includes all of those steps that I listed in my last post.

That is: W33 expanding, contacting sides of Col 79 & 44, pushed west until catches on inner surfaces of N. webs of Col 79 & 44, compressive stresses rises in W24 floor beams as a direct result of W33 being restrained at ends by column webs, W24 beams buckle & rotate W33 (rotating CCW looking from north), W33 buckles as it rotates & falls.

My contention is that, in the summary, all of the above is contained within the term "walk off".
___

How shall we settle this?

Let's see you make your case by anything other than mere assertions.

Let's see you argue like a grown-up, presenting, acknowledging & addressing the arguments AGAINST your ultimate conclusion (instead of ignoring them) as well as the argument for your conclusion.

Your thoughtful, measured reply …?


tomk
 
No, the 11" was what NIST said in the final report. The 1' 0" was what was on the drawing that NIST got its information from.

That is not an innocent mistake IMnsHO.

Your nsHO doesn't matter.

If NIST came back with a retraction, would you be satisfied?

How does this "massive oversight" change the actual outcome of the day?
 
Originally Posted by gerrycan http://www.internationalskeptics.com/forums/showthread.php?p=8122602#post8122602http://www.internationalskeptics.com/forums/helloworld2/buttons/viewpost.gif
Depends, how hot did it get? And NIST say that these beams were heated uniformly in their analysis, so their expansion would be proportional to their length. I know it's a crazy idea to think that these beams could all go to 600 deg in a few seconds and uniformly at that, but hey, that's NIST for ya.


NIST heated the entire area to 500oC [girder] and 600oC [beams] in 1.5 seconds.

NCSTAR 1-9 Vol.1 pg 352 [pdf pg 396]
Ramping of the temperatures for the beams and the girder then commenced at 1.1 s, as shown in Figure 8–25, leveling off at temperatures of 500 °C for the girder and 600 °C for the beams at 2.6 s.

ETA: This was in the preliminary "rock off"analysis where the beams buckled.

So why didn't the beams buckle when heated to 610oC* in the final analysis? They can't have it both ways.

*The temperature required to make them expand 5.5" and pushed the girder off its seat - if it were 11" wide.

Tell me that you are confused as to exactly WHY NIST brought them up to temperature in 1.5 seconds...?!!

Tell me that you think that NIST believes that this is an accurate reflection of their rate of heating in the fire.

Tell me that you think that this is one of NIST's cheats to get the answer that they want.

Please, oh please elaborate...
 
Chris,

Don't you have a thoughtful, measured reply to compose? See post #284.

Or will it be [crickets] for dinner again?


tom
 
Tell me that you are confused as to exactly WHY NIST brought them up to temperature in 1.5 seconds...?!!

Tell me that you think that NIST believes that this is an accurate reflection of their rate of heating in the fire.

Tell me that you think that this is one of NIST's cheats to get the answer that they want.

Please, oh please elaborate...

You're sooo mean :D
 
OK, so we have a difference in interpretation of the report.

You claim that "walk off" is a specific term that means the W33 girder sliding (you say 6") to the west until the girder central web is aligned with the west end of the seat & then rotating CW (looking from N to S at the side of W33 girder) & dropping.

Correct?
Incorrect. NIST said "walk off" occurred when the girder was pushed 5.5"

I say that "walk off" is a generic term for the girder falling off of the seat (in any manner), which specifically includes all the details that are described in the detailed FEA analysis of section 8.8.
That's the preliminary "rock off" hypothesis.

In other words, my definition of "walk off" includes all of those steps that I listed in my last post.

That is: W33 expanding, contacting sides of Col 79 & 44, pushed west until catches on inner surfaces of N. webs of Col 79 & 44, compressive stresses rises in W24 floor beams as a direct result of W33 being restrained at ends by column webs, W24 beams buckle & rotate W33 (rotating CCW looking from north), W33 buckles as it rotates & falls.
Ah, there's the problem. You don't know the difference between rocking and walking. The NIST graphics make it very clear that the "rock off" was to the east and the "walk off" was to the west.

Beam buckle = rock off to the east - beam no buckle = walk off to the west.

Maybe this will help you with the "rock to the east" part:
http://www.youtube.com/watch?v=gVWm9PQeYtE

And this will help with the "walk off" part:
http://www.youtube.com/watch?v=o-eWAuFmjN0

Walking is much slower than rocking. ;)

Seriously:
When NIST heated the beams to 600oC, they buckled but when they heated the beams to 610oC they did not.

"Insanity: doing the same thing over again and expecting different results." -- Albert Einstein

NIST did the same thing over again and got different results.
[FONT=&quot] :boggled:
[/FONT]
 
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Gerrycan,




Please provide a little bit of information, and then I'll debate you calmly.

How many people are in your group that produced these videos?

Please provide the following:
Person 1 has been a [profession] for [xx] years.
Person 2 has been a [profession] for [xx] years.

Person n has been a [profession] for [xx] years.

I'd just like to know the level of expertise (especially in structural or mechanical engineering) that I'm dealing with.
___

You say that you have been unsuccessful at being able to get a response from NIST, even tho you have tried several times.

Could you please post a sample of one of your typical communications to them. I'd like to get a sense of the tone of the inquiry.

You know, where it resides on the scale of "we have some questions for which we'd respectfully request some elaboration" to "who paid you off to falsify your report?"

You do realize, I assume, that if you ask exactly the same question that they've been asked by the "who are you lying for" crowd, they are smart enough to figure out who you are.

Tell me something, if you had devoted several years of your life, contributing your considerable expertise to the US in its time of need, probably getting about 20% of the compensation that you'd normally get, and a bunch of know-nothing punks publicly & repeatedly accused you of being bought & paid for, accessories after the fact to mass murder & treason, all because they are snot-nosed wet-behind-the-ears punks who haven't the slightest clue what they are yammering about, would you feel "positively inclined to help them part the clouds of their ignorance"?

How about if you had tried to do exactly this, say, 50 times, only to be met with derision and determined stupidity & a complete unwillingness to learn anything. Would you continue to beat your head against that pathetic wall?

Or would you simply say "enough", & ignore the morons?

You'll excuse me, of course. I'm "just asking questions".
___

Are you the narrator for those videos? Is your group centered in the UK, or spread about?

I assume that you are members of ae911t?

You'll get no help from ae911t architects or engineers, of course. Architects don't understand the issues. They don't do stress analysis equations, especially on damaged buildings. And the ae911t engineers … well, they've successfully passed a very effective filtering process that demonstrates them to be in the bottom 1% of the profession.

Sad, but true.

But there are hundreds of independent, unbiased structural engineers in your neck of the woods. Pretty much no matter where you live. They work in industry & academia.

If you got rid or the insulting accusatorial tone, and the ludicrous "I've never taken an engineering class in my life, but I'm certain that these career Professional Engineers are wrong" attitude, and approached one or more of these guys with your questions, I'm certain that you'd find one to help you out.

As long a the 'tude stayed in check, of course.

Why haven't you tried this?


tomk

PS. Your posting history is, shall I say, "curious".

Before yesterday (@2:44 with post #164 in this thread, you had posted exactly 8 times on a total of 3 days.

1 post on Mar 2, 2012.
1 post on Oct 4th, 2011
6 posts on Aug. 24, 2010.

When you started posting yesterday, you replied to a post of mine to Christopher7, and have since produced a fusillade of 36 posts in 1.5 days.

That's a pretty remarkable change in behavior.

Two additional questions come to mind:
1. Is Chris7 one of the members of your group?
2. Did Chris7 ask you to come here & start posting?

Hi, yes, I am the narrator of these videos. There are 4 or 5 of us who researched this. As for posting my CV on here, i dont think so. Chris7 never asked me to join this debate, and judging from his posts he has enough of a grasp on this topic not to need my back up anyhow. I watch a lot of debates here, but i do not take part in many, as you correctly note.
I am interested to know if these videos have at all clarified the position that NIST take on wtc7 to you. I would be happy to discuss this with you, you seem reasonable. Our intention here is to show NISTs story and where we think they have got it wrong, if you can correct us on some points i welcome that.
 
Our intention here is to show NISTs story and where we think they have got it wrong,
If you have addressed this elsewhere, I apologize. Why?

Why is a Scottish guy making youtubes about NIST? To what end?

What does success look like to you?
 
gerry,

Hi, yes, I am the narrator of these videos.



There are 4 or 5 of us who researched this.
As for posting my CV on here, i dont think so.

I didn't ask for your CV.

I asked for the background & experience level of the 4 or 5 that produced your video.

Here, allow me to illustrate. I'll go first.

I'm a mechanical engineer. I got my degree from Cornell University in the mid 70s. I've made my living as a project engineer & design engineer continuously ever since.

See. No CV. Just a statement of "what do you do for a living & how long have you been doing it?" Or, more precisely, "what background do you have that bears on the questions and (MUCH more important) the answers that you are offering?"

Chris7 never asked me to join this debate,

I'll take you at your word.

Coincidences do happen.

… and judging from his posts he has enough of a grasp on this topic not to need my back up anyhow.

This convinces me that you have little to no pertinent engineering experience at all.

When it comes to structures, stress analysis, failure modes, etc., Chris can literally not argue his way out of a wet paper bag.

To a knowledgeable reader, Chris would do far, far better going 3 rounds with Mike Tyson than he does here.

The only thing that has saved him from an early grave is the fact that the punches & blood are metaphorical.

The principle reason for his endurance here is an inordinately high tolerance for being shown to be a fool, or the lack of comprehension of the fundamental issues to realize how badly mauled he gets on a regular basis.

Most of us, me included, simply stop when it's just plain too cruel & embarrassing to beat his bloody pulp anymore.

Exactly as will happen here shortly.

Stay tuned.

I watch a lot of debates here, but i do not take part in many, as you correctly note.

Your choice, of course.

I am interested to know if these videos have at all clarified the position that NIST take on wtc7 to you.

Happy to say "not in the slightest".

I get my information from two sources:
1. Bona fide experts.
2. My own education & experience.

Youtube makes no appearance anywhere on the list.

And I am not guessing when I concluded - after about 2 minutes of watching your video - that you had little to no experience in structures.

I would be happy to discuss this with you, you seem reasonable. Our intention here is to show NISTs story and where we think they have got it wrong, if you can correct us on some points i welcome that.

Please answer my questions about your experience. Nobody's asking anything traceable.

Let me ask you this.

You've apparently spent some considerable time "investigating" this issue. You must have produced your version of an FMEA, of course.

There is one component of the connection between the girder & the columns that is by far the weakest link in the design.

Can you tell me which component it is, why it's the weakest link and tell us its likely failure mode?


tom

PS. I've got to get to work. I'll return to this later.

PPS. There are 2 questions that I asked you in my post above that you ignored.

1. Should NIST engineers be expected to continue to reply to accusatory know-nothings?

2. Have you taken your questions to local experienced structural engineers in industry or academia & listened carefully, respectfully to their answers?

Care to answer?
 
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If you have addressed this elsewhere, I apologize. Why?

Why is a Scottish guy making youtubes about NIST? To what end?

What does success look like to you?
I apologize for jumping in here gerrycan but this is the tried and true "ignore the facts presented and ask irrelevant questions in order to bury the facts presented with long winded irrelevant arguments" diversion from the facts tactic.
 
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The seat WAS 1' wide and the NIST hypothesis is impossible.

So the extra 1/2" of expansion required to get the c-of-g off the edge was "impossible"? Amazing. Who would have thought the integrity of such a building could come down to 1/2" of thermal expansion, given the theoretical temperatures achieved .
 
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C7,

Incorrect. NIST said "walk off" occurred when the girder was pushed 5.5"

And the question at hand is YOUR interpretation of what NIST meant by "walk off" versus MY interpretation of what they meant by "walk off".

We disagree.

Let's see you make your case by something OTHER THAN mere baseless assertion & repetition of baseless assertion.

That's the preliminary "rock off" hypothesis.

That is one way, your way, to look at it.

An alternative way, my way, is that it is the ONLY detailed FE analysis of the detailed mechanical response of the system to fire, constraints & stress. That it describes the essential details of what NIST means by "walk off".

Again, I am prepared to make my case without simply resorting to assertions.

Are you?

If so, based on history, I must insist that you go first.

Ah, there's the problem. You don't know the difference between rocking and walking. The NIST graphics make it very clear that the "rock off" was to the east and the "walk off" was to the west.

That is clearly your interpretation of their graphic.

Forgive me if I point out that there has seldom been a 1 to 1 correspondence between "what NIST meant" and "what C7 claims that NIST meant".

Walking is much slower than rocking.

And your belief of the significance of this, um, baseless assertion is … what?

The upper blocks of WTC2 & 1 "rocked" for 1 hour & two hours respectively before they collapsed. Meanwhile they went thru much quicker cycles of thermal expansion & contraction. "Rocking" does not have to be faster than thermal expansion.

Seriously:
When NIST heated the beams to 600oC, they buckled but when they heated the beams to 610oC they did not.

"Insanity: doing the same thing over again and expecting different results." -- Albert Einstein

NIST did the same thing over again and got different results.

And you aren't capable of understanding the different mechanical effects that were responsible for this?

That's pretty lame, Chris.


tk

PS. Now I'm late & I've really got to go...
 
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Hi, yes, I am the narrator of these videos. There are 4 or 5 of us who researched this. As for posting my CV on here, i dont think so. Chris7 never asked me to join this debate, and judging from his posts he has enough of a grasp on this topic not to need my back up anyhow. I watch a lot of debates here, but i do not take part in many, as you correctly note.
I am interested to know if these videos have at all clarified the position that NIST take on wtc7 to you. I would be happy to discuss this with you, you seem reasonable. Our intention here is to show NISTs story and where we think they have got it wrong, if you can correct us on some points i welcome that.

Before yesterday (@2:44 with post #164 in this thread, you had posted exactly 8 times on a total of 3 days.

1 post on Mar 2, 2012.
1 post on Oct 4th, 2011
6 posts on Aug. 24, 2010.

When you started posting yesterday, you replied to a post of mine to Christopher7, and have since produced a fusillade of 36 posts in 1.5 days.

That's a pretty remarkable change in behavior.

Two additional questions come to mind:
1. Is Chris7 one of the members of your group?
2. Did Chris7 ask you to come here & start posting?

I too am curious about this timeline. What happened that caused you to return to JREF?
 
So the extra 1/2" of expansion required to get the c-of-g off the edge was "impossible"? Amazing. Who would have thought the integrity of such a building could come down to 1/2" of thermal expansion, given the theoretical temperatures achieved .
Certainly no one here.

The beam would have to be heated to roughly* 660oC to expand 5.5 inches. It would have lost well over half of its strength and probably be sagging at that point. The beam would have to be heated to 738oC to expand 6 inches butt would lose up to 80% of its strength and sag for sure while being heated to 738oC in the real world. Therefore, it could not push the girder laterally 6 inches.

Even if it could, the stiffeners would prevent the bottom flange from folding for another few inches. Even if the bottom flange folded, the girder would land on the 2" support plate.

The girder that supposedly started the cascade of collapsing floors that left column 79 unbraced for 9 stories and allowed it to buckle, could not and did not happen.


This is not an opinion, its the laws of thermodynamics as they apply to steel beams.


*The simplistic method NIST used is inaccurate. Expansion of steel is not lineal. The spreadsheet shows a temperature 40oC greater than the NIST method to get 6 inches of expansion.
 
The girder that supposedly started the cascade of collapsing floors that left column 79 unbraced for 9 stories and allowed it to buckle, could not and did not happen.

So we have what - 3 impossibilities now?

1) The girder that started the collapse couldn't have failed in the manner stated
2) Explosives could not have been planted and detonated to facilitate collapse
3) Therm*te could not have been planted and lit to facilitate collapse


So in your opinion, what's left?
 
Certainly no one here.

The beam would have to be heated to roughly* 660oC to expand 5.5 inches. It would have lost well over half of its strength and probably be sagging at that point. The beam would have to be heated to 738oC to expand 6 inches butt would lose up to 80% of its strength and sag for sure while being heated to 738oC in the real world. Therefore, it could not push the girder laterally 6 inches.

Even if it could, the stiffeners would prevent the bottom flange from folding for another few inches. Even if the bottom flange folded, the girder would land on the 2" support plate.

The girder that supposedly started the cascade of collapsing floors that left column 79 unbraced for 9 stories and allowed it to buckle, could not and did not happen.


This is not an opinion, its the laws of thermodynamics as they apply to steel beams.


*The simplistic method NIST used is inaccurate. Expansion of steel is not lineal. The spreadsheet shows a temperature 40oC greater than the NIST method to get 6 inches of expansion.

What did these beams weigh? Did the lower beams weigh more/less than upper beams? Which beams sagged first, upper/lower beams? Did the columns get pushed out or pulled in...or both? At what floor did this happen first? At what temp did welded areas begin to change? At what temp did bolts begin to change?
 
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