Total Building Collapse from a Single Column Failure

[NoahFence]

I actually laughed out loud at this.
Look again.
What do you see restraining the girder from C76 - 79.
NB not the girder spanning 79 and 44.

I see a straight black line exactly as impervious to fire as whatever it is you're trying to get me to see.

 

[Reactor drone]

I actually laughed out loud at this.
Look again.
What do you see restraining the girder from C76 - 79.
NB not the girder spanning 79 and 44.

Since there's no girder framing directly onto the east of column 79, expansion of the girder between columns 76 and 79 can move column 79 to the east with only the floor to resist it. I agree that the girder spanning column 44-79 wont restrain it in that direction and neither will the column 79-80 girder..

The temperature of the girder between Columns 76 and 79 on Floor 13 was sufficient to displace Column 76 to the west and Column 79to the east
(pg 527 NIST NCSTAR 1-9)

 

[DGM]

I agree that the girder spanning column 44-79 wont restrain it in that direction and neither will the column 79-80 girder..

I think it might confuse him when we agree but, say it does not support his belief.

I really wish he would ask for help and not tell everyone their wrong (or post irrelevant crap). It might shed a little light on why no engineering venues will listen.

 

[Animal]

It won't.

(given the constraints you put it under).

It is a straw man set up in the only way that it works to maintain his religious beliefs........meanwhile in reality......"Temperature gradients through the depth of the steel beams and girders were affected by the presence of the floor slab. Temperatures were uniform (within 1C) across the bottom flange and web, but the top flange temperature was less by up to several hundred degrees, because the slab acted as a heat sink (see Figure 4-6 to Figure 4-8)" (pg 391 NIST NCSTAR 1-9)

 

[Animal]

It does no such thing.How did NIST model conductivity in the steel, and the slab?

If you have to ask.....then making the highlight statement makes you an even bigger fool

 

[DGM]

It is a straw man set up in the only way that it works to maintain his religious beliefs........

Tony knows this, gerrycan.............................

 

[Tony Szamboti]

Tony knows this, gerrycan.............................

You will have to speak for yourself.

From my perspective none of the NIST apologists here have been able to scientifically defend the WTC 7 report that NIST put out. We really can't count the cries of "the building was on fire and fell down. What else is there to know?"

 

[Grizzly Bear]

Please show how a 53ft beam expands more than 5.5in. What temperature is required for it to do so?
Remember that the beam will sag above 600C and lose the ability to push.

Good grief man... ._.
You spend so much time concerned with the length of expansion that you don't think about more pressing issues that arise from that, like the fact that anything restrained to it is having a force exerted on it, and that the component receiving the force has to resist it potentially as an eccentric load which could cause failure at a lower magnitude than if the force were applied properly. You're putting so much emphasis on that 5" figure when in building design a half inch change in length is enough to cause problems on a pristine building (Why do you think expansion joints exist?)

And you wonder why people are chastising you about minutia? You do realize that the minutia you and Tony spend so much time on are also dependent on larger scale details that your criticisms do NOT account for, right?

 

[Tony Szamboti]

Good grief man... ._.
You spend so much time concerned with the length of expansion that you don't think about more pressing issues that arise from that, like the fact that anything restrained to it is having a force exerted on it, and that the component receiving the force has to resist it potentially as an eccentric load which could cause failure at a lower magnitude than if the force were applied properly. You're putting so much emphasis on that 5" figure when in building design a half inch change in length is enough to cause problems on a pristine building.

And you wonder why people are chastising you about minutia? You do realize that the minutia you and Tony spend so much time on are also dependent on larger scale details that your criticisms do NOT account for, right?

You aren't framing the problem correctly if you are saying the beams were restrained. Remember, according to NIST, the beams broke their shear studs and the girder had no shear studs, so it could not resist the movement by the beams.

However, the girder can't come off its seat with 5.5" of beam movement. It would actually require a lot more movement that that, so is NIST just making things up? The drawings and science says whoever is behind the NIST WTC 7 report is doing just that.

 

[Animal]

You will have to speak for yourself.

From my perspective none of the NIST apologists here have been able to scientifically defend the WTC 7 report that NIST put out. We really can't count the cries of "the building was on fire and fell down. What else is there to know?"

"the building was on fire and fell down. What else is there to know"
is a far more reasonable cause than troofers " I just know the NIST report is wrong so it must be a CD" nonsense.

 

[thedopefishlives]

You will have to speak for yourself.

From my perspective none of the NIST apologists here have been able to scientifically defend the WTC 7 report that NIST put out. We really can't count the cries of "the building was on fire and fell down. What else is there to know?"

You have yet to demonstrate that any of your concerns alter the ultimate conclusion of the report. Show us the evidence that your alterations to the model would result in the building absolutely not falling down.

 

[DGM]

You will have to speak for yourself.

From my perspective none of the NIST apologists here have been able to scientifically defend the WTC 7 report that NIST put out. We really can't count the cries of "the building was on fire and fell down. What else is there to know?"

I was giving you the benefit of the doubt. Sorry.

 

[pgimeno]

So the furthest to the West that the girder can be pushed by means of thermally expanding beams to the East of it is equal to or less than 5.5in.
NIST claim 6.25in.

False. Plain false.

NIST claim that the girder moved to the west an unspecified distance due to thermal expansion, and that their FEA shows the girder walking off.

They don't claim that the 6.25 in. the girder moved off the seat matched the thermal expansion of the beams. That's a mistake you're making all the time.

And in that regard, your analysis has a number of unexplained assumptions that are fatal to your claims. It's time for you to address them.

1. You assume that the exterior end of the beams is fixed. You have provided no justification.
2. You assume that the beam that pushed the girder is the closest to the connection. Your justification is that it's the longest one; however, that justification is not valid, since leveraging is able to amplify the displacement of the girder further than the elongation of the beam, and the farther from the connection, the bigger the amplification factor will be.
3. You assume that the seat is in the same position all the time. You've provided no justification.
4. Your analysis lacks any consideration of creep. NIST's FEA includes it.

And while on it:

5. You assume that the girder's web being completely off the seat is a perfectly stable condition. You give no justification.

Put simply, you assume that maximum expansion of the beams = maximum displacement of the girder from the center of the seat, but you fail to justify that assumption. That failure is fatal to your claims.

 

[beachnut]

... You may lack the moral fiber, intelligence or maybe just the courage to face the possibility that may threaten your world view, but if you seek to make denials of science and logic to me, you will have to go and borrow a shred of intellectual rigor from somewhere and it is not something that i see evidence of availability of in you or your likes.

You spread lies of CD, and can't do more than attack a study no one needs to figure out 19 terrorists did 911 with a simple two steps 911 truth will never grasp in their paranoid anti-government movement of woo, CD, thermite, and nonsense.

No grasp of reality, 911 truth makes up missiles, thermite, CD, no planes, and ignores 19 terrorists.

WTC 7 burned for hours, fires not fought, the building was totaled before it collapsed. 911 truth uses the gravity collapse caused by fires of WTC 7 as their smoking gun for crazy claims, and ignores 19 murderers. Did a single column failure destroy WTC 7? No, it was a fire and lots of damage that caused the collapse, and the best 911 truth can do is weakly attack a probable cause from NIST. Unable to do real engineering work we have the fantasy of CD and thermite based on the ranting of old men who love conspiracy theories, and blame the USA, blame their country for their failure. Old men with thermite fantasy CD - fooled people who fail to understand reality.

Fire caused the collapse, has anyone run the simulation to see if removing one column can cause a failure; or does it take lots of general damage and then a single column failure? A chain of events cause the collapse of WTC 7, 911 truth had to have fantasy to make in happen, and delusional opinions.

Why can't 911 truth make any progress? Watergate took a year to break, 911 truth claims will take infinite time. The fantasy will never die, education does not take in all humans. Many first graders were daydreaming when I covered cause and effect, a few picked it up and could teach it. I think I was daydreaming too in first grade, but UPT, BSEE, and MSEE, an ATP, USAF FIS, USAF AIT, etc helped me back in the stuff I failed to learn in grade school.

As I know by observation, a grade school education is all that is needed to understand 911, and to find 911 truth is based on nonsense.

Who has that single column failure model?

 

[Reactor drone]

I think it might confuse him when we agree but, say it does not support his belief.

I really wish he would ask for help and not tell everyone their wrong (or post irrelevant crap). It might shed a little light on why no engineering venues will listen.

I do like how his argument seems to be diametrically opposed to his claims.

 

[Tony Szamboti]

False. Plain false.

NIST claim that the girder moved to the west an unspecified distance due to thermal expansion, and that their FEA shows the girder walking off.

They don't claim that the 6.25 in. the girder moved off the seat matched the thermal expansion of the beams. That's a mistake you're making all the time.

And in that regard, your analysis has a number of unexplained assumptions that are fatal to your claims. It's time for you to address them.

1. You assume that the exterior end of the beams is fixed. You have provided no justification.
2. You assume that the beam that pushed the girder is the closest to the connection. Your justification is that it's the longest one; however, that justification is not valid, since leveraging is able to amplify the displacement of the girder further than the elongation of the beam, and the farther from the connection, the bigger the amplification factor will be.
3. You assume that the seat is in the same position all the time. You've provided no justification.
4. Your analysis lacks any consideration of creep. NIST's FEA includes it.

And while on it:

5. You assume that the girder's web being completely off the seat is a perfectly stable condition. You give no justification.

Put simply, you assume that maximum expansion of the beams = maximum displacement of the girder from the center of the seat, but you fail to justify that assumption. That failure is fatal to your claims.

If you actually read what NIST says, as to how they determined that the girder had failed, you wouldn't say it was based on the FEA showing the girder walked off.

In the fourth paragraph on page 527 of NIST NCSTAR 1-9, you can see them say for yourself

Walk-off occurred when beams that framed into the girders from one side thermally expanded and the resulting compressive forces in the beams pushed laterally on the girder from one side, sheared the bolts at the seated connection, and then continued to push the girder laterally until it walked off the bearing seat. A girder was considered to have lost vertical support when its web was no longer supported by the bearing seat. The bearing seat at Column 79 was 11 in. wide. Thus, when the girder end at Column 79 had been pushed laterally at least 5.5 in., it was no longer supported by the bearing seat. Additional factors that contributed to this failure were the absence of shear studs on the girders that would have provided lateral restraint and the one-sided framing of the northeast corner floor beams that allowed the floor beams to push laterally on the girder due to thermal expansion.

The bolded line shows they made a determination, not that the FEA showed it happening. With the stiffeners included there would never be enough stress to cause the girder flange to fail so saying it did because the web was no longer directly over the bearing seat would not be an accurate measure for failure.

Based on what was in the original final report as shown above, along with the erratum of June 2012 where they correct the seat length to 12 inches from 11 inches and then say the lateral travel was 6.25 inches, they are still implying it is from the beams expanding as they provide no other mechanism for the movement of the girder web off the bearing seat. Of course, the beams can't expand 6.25 inches so they have a problem.

What is telling is that they don't show how column 79 could be pushed to the east to make up the difference, as some here want to simply assert, and with the stiffeners involved the walk-off distance is significantly greater than 6.25 inches.

Unless you can find a way to break the bolts of the connection of beam K3004 to girder A2001 it will limit the pushing of the girder to 5.5 inches.

You will also have to excuse me if I don't see where NIST mentions creep in relation to their alleged girder failure.

The girder would be stable with its web past the seat with the stiffeners involved and the K3004 beam connection to the girder intact. There is a reason the stiffeners were omitted. Some here just don't want to face that reality.

 

[ozeco41]

...They don't claim that the 6.25 in. the girder moved off the seat matched the thermal expansion of the beams. That's a mistake you're making all the time...

It is probably time that someone put it as blunt as that.

As I've said several times their logic is arse about AND they should read what NIST actually wrote.

 

[LudicFallacies]

False. Plain false.

NIST claim that the girder moved to the west an unspecified distance due to thermal expansion, and that their FEA shows the girder walking off.

They don't claim that the 6.25 in. the girder moved off the seat matched the thermal expansion of the beams. That's a mistake you're making all the time.

And in that regard, your analysis has a number of unexplained assumptions that are fatal to your claims. It's time for you to address them.

1. You assume that the exterior end of the beams is fixed. You have provided no justification.
2. You assume that the beam that pushed the girder is the closest to the connection. Your justification is that it's the longest one; however, that justification is not valid, since leveraging is able to amplify the displacement of the girder further than the elongation of the beam, and the farther from the connection, the bigger the amplification factor will be.
3. You assume that the seat is in the same position all the time. You've provided no justification.
4. Your analysis lacks any consideration of creep. NIST's FEA includes it.

And while on it:

5. You assume that the girder's web being completely off the seat is a perfectly stable condition. You give no justification.

Put simply, you assume that maximum expansion of the beams = maximum displacement of the girder from the center of the seat, but you fail to justify that assumption. That failure is fatal to your claims.

Well put pgimeno.

Also, Tony I'm sorry for calling you a narcissist earlier as it was out of line and uncalled for and for that I can only apologize and try to be civil.

 

[Animal]

If you actually read what NIST says, as to how they determined that the girder had failed, you wouldn't say it was based on the FEA showing the girder walked off.

Maybe you should take your own advise.

In the fourth paragraph on page 527 of NIST NCSTAR 1-9, you can see them say for yourself

Walk-off occurred when beams that framed into the girders from one side thermally expanded and the resulting compressive forces in the beams pushed laterally on the girder from one side, sheared the bolts at the seated connection, and then continued to push the girder laterally until it walked off the bearing seat. A girder was considered to have lost vertical support when its web was no longer supported by the bearing seat. The bearing seat at Column 79 was 11 in. wide. Thus, when the girder end at Column 79 had been pushed laterally at least 5.5 in., it was no longer supported by the bearing seat. Additional factors that contributed to this failure were the absence of shear studs on the girders that would have provided lateral restraint and the one-sided framing of the northeast corner floor beams that allowed the floor beams to push laterally on the girder due to thermal expansion.

The bolded line shows they made a determination, not that the FEA showed it happening. With the stiffeners included there would never be enough stress to cause the girder flange to fail so saying it did because the web was no longer directly over the bearing seat would not be an accurate measure for failure.

Based on what was in the original final report as shown above, along with the erratum of June 2012 where they correct the seat length to 12 inches from 11 inches and then say the lateral travel was 6.25 inches, they are still implying it is from the beams expanding as they provide no other mechanism for the movement of the girder web off the bearing seat. Of course, the beams can't expand 6.25 inches so they have a problem.

Which is course not true.....unless of course you hand wave away.
The temperature of the girder between Columns 76 and 79 on Floor 13 was sufficient to displace Column 76 to the west and Column 79to the east
(pg 527 NIST NCSTAR 1-9) ....oh wait......you do right here

What is telling is that they don't show how column 79 could be pushed to the east to make up the difference, as some here want to simply assert, and with the stiffeners involved the walk-off distance is significantly greater than 6.25 inches.

And once again you fail to take your own advice....

Unless you can find a way to break the bolts of the connection of beam K3004 to girder A2001 it will limit the pushing of the girder to 5.5 inches.

The forced displacements at Floors 10, 11 and 12 created a tensile load in the girder knife connections to the columns, and failed the connection fillet welds to the column. (pg 527 NIST NCSTAR 1-9)

You will also have to excuse me if I don't see where NIST mentions creep in relation to their alleged girder failure.

Appendix E

The girder would be stable with its web past the seat with the stiffeners involved and the K3004 beam connection to the girder intact. There is a reason the stiffeners were omitted. Some here just don't want to face that reality.

Te pristine building theory......and you wonder why you will never be taken seriously outside of your troofer bubble?

( don't forget the added seat stiffener )

 

[Muc]

Has this been adressed already?

The National Institute of Standards and Technology (NIST) has declined a request to open an investigation into correcting errors in its report on the collapse of World Trade Center Building 7 during the September 11th attacks. The decision is in response to a complaint filed with the Office of Inspector General (OIG) by attorney Dr. William Pepper on behalf of contributing members of Architects and Engineers for 9/11 Truth ... The April 14th response comes three months after a NIST spokesperson confirmed receiving notice on January 15, 2014.

http://wtfrly.com/2014/04/17/nist-waits-3-months-decline-fix-flawed-wtc7-report/

That was eleven days ago - yet I can't seem to find the content of NIST's reply anywhere. I don't even see it mentioned anywhere except in that quote. Was it a simple "thanks for the letter, but ... nah" or did they actually bother to state why they thought the objections were not relevant? I also wonder if that information was already sent to the people represented by Pepper, some of whom I understand are posting in this very thread, or just given to the authors of the above-linked article after direct inquiry.