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

[NoahFence]

People like you and TFK need to support their claims.

If you're ever confused on what the word "audacity" means, look up that post from a truther.

Oh. My. God.

I've been asking YOU to support your claim, to no avail, for DAYS.

You're a hypocrite. In case you don't realize, that's not a very good trait.

 

[triforcharity]

Sure it does. You haven't supported your claim that TFK's claim had any merit showing I was wrong.

Basically, you were making the unsupported claim that I am saying I am right simply because I say so, and that you don't need to show any math to show otherwise. That isn't true. The math supports what I am saying and to counter it you have to show I am wrong, and yes you need to show the math.

You've been shown to be wrong, in this very thread. What's sad, is that I have no experience in structural engineering, and see where you've gone so wrong. TFK makes excellent points, which you refuse to address, and instead, run around like a lost puppy dog looking for his home.

Why don't you address TFK's posts?

Also, as an aside, can we see your FEA data?

 

[Tony Szamboti]

You've been shown to be wrong, in this very thread. What's sad, is that I have no experience in structural engineering, and see where you've gone so wrong. TFK makes excellent points, which you refuse to address, and instead, run around like a lost puppy dog looking for his home.

Why don't you address TFK's posts?

Also, as an aside, can we see your FEA data?

You and TFK are simply talking in circles and just saying I am wrong without proving it. That doesn't work.

TFK needs to support his counter claims before I need to address them. He has not done that. Let's see some math from you guys.

I first performed a conservative hand calculation using known equations to back up my point showing TFK was incorrect with his claim that column 79 could have been pushed 4.5 inches to the east at floor 13 by the girder framing into it from column 76. I did the additional supporting FEA in work on my own time and will send a slide of it home next week and post it.

Nobody has shown I am wrong concerning the points proving that the NIST theory for the collapse initiation of WTC 7 is impossible.

 

[Justin39640]

You and TFK are simply talking in circles and just saying I am wrong without proving it. That doesn't work.

TFK needs to support his counter claims before I need to address them. He has not done that. Let's see some math from you guys.

I first performed a conservative hand calculation using known equations to back up my point showing TFK was incorrect with his claim that column 79 could have been pushed 4.5 inches to the east at floor 13 by the girder framing into it from column 76. I did the additional supporting FEA in work on my own time and will send a slide of it home next week and post it.

Nobody has shown I am wrong concerning the points proving that the NIST theory for the collapse initiation of WTC 7 is impossible.

Why does it seem like you're arguing the point for a single floor and might be ignoring the rest of the damage to the building? Not sure if that's the case though.

 

[Tony Szamboti]

Why does it seem like you're arguing the point for a single floor and might be ignoring the rest of the damage to the building? Not sure if that's the case though.

Have you read the NIST WTC 7 report? If so, where and how do they say the collapse initiated?

 

[Justin39640]

Have you read the NIST WTC 7 report? If so, where and how do they say the collapse initiated?

Fire-induced thermal expansion of the floor system surrounding Column 79 led to the collapse of Floor 13, which triggered a cascade of floor failures. In this case, the floor beams (plural) on the east side of the building expanded enough that they pushed the girder connecting Columns 79 and 44 to the west on the 13th floor. (See Figure 1–5 for column numbering and the locations of girders and beams.) This movement was enough for the girder to lose its connection to Column 79. The displaced girder and other local fire-induced damage caused Floor 13 to collapse, beginning a cascade of floor failures down to the 5th floor (which, as noted in Section 1.2.3, was much thicker and tronger). Many of these floors had already been at least partially weakened by the fires in the vicinity of Column 79. This left Column 79 with insufficient lateral support in the east-west direction. The column buckled eastward, becoming the initial local failure for collapse initiation.

Sounds like more that a simple hand calculation is needed to me.

 

[Tony Szamboti]

Sounds like more that a simple hand calculation is needed to me.

It sounds like you are confusing what I said about proving TFK incorrect about the girder between columns 76 and 79 pushing column 79 to the east by 4.5 inches, with the overall NIST scenario.

There have been a number of calculations done on the various features of the building construction in that area which show that there is no systemic way that fire could cause the NIST scenario for collapse initiation.

 

[LSSBB]

It sounds like you are confusing what I said about proving TFK incorrect about the girder between columns 76 and 79 pushing column 79 to the east by 4.5 inches, with the overall NIST scenario.

There have been a number of calculations done on the various features of the building construction in that area which show that there is no systemic way that fire could cause the NIST scenario for collapse initiation.

Very interesting, I haven't seen your work. First, answer these questions:

Tony,

We'll start with the simple stuff.

I'm not asking these for information. I know the answers. I want to see if you do.

1. Please draw the stress-strain curves (one curve for each temperature) implied by your values for E(Temp) from a strain of zero up to the max strain that you think is appropriate for your assumptions. (The assumptions that you haven't provided yet.)

2. Do you see any problem with using end constraints of "simple supports" for very low temps?

3. Why did you not build your model considering construction loads?

4. What are the underlying assumptions associated with the deflection curve for distributed load equation that you used? Paying primary attention to where the equation breaks down & gives wrong answers.

5. What is the fundamental theoretical justification used in the generation of the distributed load equation that you used?

That'll do for now.


Tom

 

[Christopher7]

Very interesting, I haven't seen your work. First, answer these questions:

Ask questions, demand answers, never do calculations, just ask more questions.

 

[LSSBB]

Ask questions, demand answers, never do calculations, just ask more questions.

I haven't seen any calculations proving your case, so why should I do any calculations? I do enough calculations in my job. I do them all the time, to prove things. How about you?

 

[Tony Szamboti]

I haven't seen any calculations proving your case, so why should I do any calculations? I do enough calculations in my job. I do them all the time, to prove things. How about you?

We have shown here on this thread, with calculations, that the NIST theory for collapse initiation of WTC 7 is impossible. With the construction details now known there is no systemic way with fire that they can get anywhere near the expansion needed to push the girder between columns 44 and 79 off its seats and none of the hypothesized contraction notions work either.

If you don't agree show your own calculations that would show we aren't correct.

Otherwise you have no leg to stand on and shouldn't be asking for more information.

 

[LSSBB]

We have shown here on this thread, with calculations, that the NIST theory for collapse initiation of WTC 7 is impossible. With the construction details now known there is no systemic way with fire that they can get anywhere near the expansion needed to push the girder between columns 44 and 79 off its seats and none of the hypothesized contraction notions work either.

If you don't agree show your own calculations that would show we aren't correct.

Otherwise you have no leg to stand on and shouldn't be asking for more information.

Where? I didn't see your work...just reports of numbers. And since you aren't answering tfk's questions, it looks to me like your avoiding something. Why not answer the questions?

 

[A W Smith]

Retarded is the interpretation of what I posted.

Please The breeze from the NW was blowing thru the building, mixing with and cooling the hot gasses from the fire. If you want to know exactly how much, do the math yourself.

Yes, retarded is thinking a breeze blowing thru the building would not cool the air temperature down.

yeah that's why blacksmiths use a bellows! To cool down the fire!

Continue basking in your ignorance Sarns. You are very entertaining!

 

[Justin39640]

It sounds like you are confusing what I said about proving TFK incorrect about the girder between columns 76 and 79 pushing column 79 to the east by 4.5 inches, with the overall NIST scenario.

There have been a number of calculations done on the various features of the building construction in that area which show that there is no systemic way that fire could cause the NIST scenario for collapse initiation.

You asked me if I read the report and if I knew how they said it initiated. They also imply all of the floors surrounding 79 were compromised.

 

[Tony Szamboti]

You asked me if I read the report and if I knew how they said it initiated. They also imply all of the floors surrounding 79 were compromised.

How do you think the collapse initiated Justin?

 

[carlitos]

He continues to avoid those simple questions. Strange.

 

[Tony Szamboti]

Where? I didn't see your work...just reports of numbers. And since you aren't answering tfk's questions, it looks to me like your avoiding something. Why not answer the questions?

Really?

I gave the equations and assumptions you participated in asking for.

What didn't you understand about the beam's thermal expansion, deflection due to temperature, and the shortening resulting from that?. You should also be aware of the web to flange stiffeners on the girder between column 44 and 79 shown on Frankel Steel drawing 9114.

The expansion and shortening occurring simultaneously in the beams to the east of the girder between columns 44 and 79 gives a maximum of 4.753" net expansion at 649 degrees C. After that the shortening is greater than expansion. Even giving an inch or so to TFK's notion that the west side girder at floor 13 pushed column 79 to the east doesn't do it, as the girder between columns 44 and 79, with the web to flange stiffeners at the column 79 side, needs to be pushed about 9.4", before there wouldn't be enough surface area to support the load by the stiffened flange. So the calculations show NIST doesn't have a basis for the claim that the girder was pushed off it's seat.

If you or any others have a problem with the methods or results you need to show why they aren't correct using actual values and math. It is time for those of you who seem to disagree to put up or shut up, not ask more questions. Otherwise, it really does seem that you are protesting too much.

 

[carlitos]

Really?

I gave the equations and assumptions you participated in asking for.

What didn't you understand about the beam's thermal expansion, deflection due to temperature, and the shortening resulting from that?. You should also be aware of the web to flange stiffeners on the girder between column 44 and 79 shown on Frankel Steel drawing 9114.

The expansion and shortening occurring simultaneously in the beams to the east of the girder between columns 44 and 79 gives a maximum of 4.753" net expansion at 649 degrees C.

Why would anything be simultaneous or symmetrical in a fire?

Why are you using 3 decimal points to describe the expansion?

Why are you measuring the temperature to a specific degree with no margin of error?

Are you really an engineer? A stupid MBA in Marketing is noting these things in your posts.

 

[Justin39640]

How do you think the collapse initiated Justin?

Not because of explosives

 

[Tony Szamboti]

Why would anything be simultaneous or symmetrical in a fire?

Why are you using 3 decimal points to describe the expansion?

Why are you measuring the temperature to a specific degree with no margin of error?

Are you really an engineer? A stupid MBA in Marketing is noting these things in your posts.

It sounds like you are one of those "we can't possibly know anything because everything is in a state of flux, and anything can happen" handwringers who doesn't know enough to critique an engineering analysis.

3 decimal places are important to show where the limit of expansion occurred.

The temperature given is for the maximum possible expansion, no matter what the temperature reached. What are you even talking about with a margin of error?

Edited by jhunter1163: 

Edited for Rule 0.