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

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Christopher7 said:
You are talking about yourself.

The rest of the diatribe that followed is just word games that I did not waste my time reading.

NIST lied about the stiffeners and the width of the seat to make their theory work. That is not an "irrelevant detail" and you know it. You are just using the JREF hand wave of evidence you can't refute.
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Unless you can prove fire and damage alone couldn't have made that building collapse, I couldn't care less what you claim NIST did. That's the irrelevant detail.
 
Clayton Moore said:
More cause why questions.

There were fires under the rubble for over 2 months.

Debunker responses.

What fires?
There was no fire.
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Who claimed this? Link to the post, please.

(later) There were fireS
There were no fires.
Many types of fires are unable to be put out.
Ad infinitum!
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Your questions got answered. It was very difficult to even get the water to the fires, much less fight them effectively. Such a thing is not all that unlikely.
 
Clayton Moore said:
Although evidence and an investigation didn't seem to be a priority it would seem the any ongoing fire(s) would be destroying evidence and delaying an investigation of a "terrorist" attack on American soil.
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And? It was physically impossible for them to extinguish the fires sooner without massive effort. And it's not like there weren't, literally, tons of evidence for what happened.

Plus the inability to extinguish the fires for 99 days makes even less sense for natural collapse of THREE huge buildings.
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These were not "natural" collapses, since they were all initiated, directly or indirectly, by planes crashing into buildings.

The examples of fires that can't be extinguished are not even close to the 9/11 circumstances/setting.
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Please specify. You have provided absolutely no evidence that the FDNY should've been able to extinguish the fires, and when others provide evidence to the contrary, you can only respond with incredulity and straw men while avoiding direct questions.

And of course the reports of molten steel are responded to by the duhbunkers in a similar cause why fashion.

What molten steel?
There was no molten steel.
There was molten steel. So what?

Ad infinitum!

If there was molten steel, which I believe there was in the basements of all three WTC buildings, it is a known fact that office material fires don't burn hot enough to melt steel.
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Assuming that's true, how would the presence of molten steel necessarily indicate CD? Because CD doesn't cause molten steel either.
 
C7 said:
NIST lied about the stiffeners and the width of the seat to make their theory work. That is not an "irrelevant detail" and you know it. You are just using the JREF hand wave of evidence you can't refute.
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twinstead said:
Unless you can prove fire and damage alone couldn't have made that building collapse, I couldn't care less what you claim NIST did. That's the irrelevant detail.
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Sillyness.

It is impossible to prove a negative and you know it.

We have shown where NIST lied about the stiffeners and seat width. You choose to ignore this and ask the impossible.
 
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Christopher7 said:
Sillyness.

It is impossible to prove a negative and you know it.

We have shown where NIST lied about the stiffeners and seat width. You choose to ignore this and ask the impossible.
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The web stiffeners do nothing for the lateral forces on the girders or mitigated their failure, they're there to stiffen the web from vertical shear at the two support points. They were irrelevant to their model.

BasqueArch said:
Location of fires and temperatures.
”The major fires on Floors 7 through 9 and 11 through 13 in WTC 7 were simulated suing the Fire Dynamics Simulator (FDS), version 4, in a manner similar to the simulations conducted for WTC1 and WTC 2 … There were far fewer photographs and videos of WTC 7 than of the towers; and thus, the details of the WTC 7 fires were not as precise as for the fires in the towers. However the imagery was sufficient to guide the WTC 7 fire simulations. … While use was made of the appearance of flames and window breakage in photographs and videos in formulating the simulations, the Investigation Team realized that the absolute timing of the simulations might not align exactly with the timing of the fires on September 11, 2001.” NCSTAR 1A [p.32].

C7’s page showing claimed discrepancies between NIST’s photos and fire simulation for the 12th floor:
WTC_fire_sim_comparison_080912c1.jpg


WTC7 NCSTAR 1-9 for photos
http://www.nist.gov/customcf/get_pdf.cfm?pub_id=861611

For the 12th floor - Floor plan NCSTAR 1-9 [p 56] showing gyp board offices layout.

For NIST gas temperatures simulation. Times are actual PM.
http://imageshack.us/clip/my-videos/696/hhs.mp4/

Column 1 - Row 1-4. C7 has clearly photoshopped globs of fire to match the NIST photos in column 2. No internal fires besides the ones attached to the windows are shown. The NIST FDS simulation shows fire progression bounded and spreading by the straight office walls and on the interior where the fires can't be seen due to the perimeter office but can be modeled. There is no calculation or software producing these images.

Column 1 Row 4. C7 doesn’t show fires on floor 12. NIST photo Column 2 Row 4 shows a fire at the NW windows area.. C7 doesn’t show fires inside which can’t be seen due to the gyp board offices walls surrounding the perimeter. C7 simulation doesn’t match photo.
Columns 2,3 Row 1; NIST photo and simulation. Photo is labeled by C7 East 2:10PM; actual NIST label is 2:11 PM. Simulation labeled 2PM. Actual simulation shows fire on the east side windows at 2:20 PM. NIST photo and simulation do not exactly match by 9 minutes.

Columns 2,3 Row 2; NIST photo and simulation. Photo is labeled by C7 North 3:05PM; actual NIST label is 3:05 PM +- 5 min. Simulation labeled 3:00 PM. Actual simulation shows fire on the north wall between 3:05 and 3:10 PM. NIST photo and simulation match.
Columns 2,3 Row 3; NIST photo and simulation. Photo is labeled by C7 North 3:50PM; actual NIST label is 3:49 - 3:54 PM. Simulation labeled 4:00 PM. Actual simulation shows fires at Northeast windows between 3:49 - 3:54 PM, photo does not. NIST photo and simulation do not match.

Columns 2,3 Row 4; NIST photo and simulation. Photo is labeled by C7 NW corner ~ 4:45 PM; actual NIST label is 5:00 PM uncertainty 10 minutes. Simulation labeled 5:00 PM. Actual simulation shows fire on the NW side windows between 4:55 - 5:05 PM. NIST photo and simulation match.NIST photos and temperature simulation match for two out of the four examples, and one lags by 9 minutes as explained by NIST above.

The gas temperatures as shown by the simulation at the 12th floor ceiling remained above 500 C, even after the fires moved on to other locations continuing to damage the structure.

I doubt AE911T or C7 will correct these mistakes about the NIST photos not matching the fire simulation or that the fire had completely burned out on floor 12 before 4:45 PM.
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We have shown where you lied about your and NIST's photos and simulation. You choose to ignore this.
 
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Christopher7 said:
Sillyness.

It is impossible to prove a negative and you know it.

We have shown where NIST lied about the stiffeners and seat width. You choose to ignore this and ask the impossible.
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Source? We?; you got a mouse in your pocket?
Source the we have shown. Explain the we.

What is your claim, and when will you prove it? You have shown nothing.
 
BasqueArch said:
The web stiffeners do nothing for the lateral forces on the girders or mitigated their failure, they're there to stiffen the web from vertical shear at the two support points. They were irrelevant to their model.
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Wrong. The bottom flange had to fold when the girder was pushed 5.5 inches to the west for the girder to fall in NIST model. The stiffeners would have prevented that.
 
Christopher7 said:
Wrong. The bottom flange had to fold when the girder was pushed 5.5 inches to the west for the girder to fall in NIST model. The stiffeners would have prevented that.
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Your'e the one that's wrong . The bottom flange did not have to fold when the girder was pushed 5.5 inches to the west for the girder to fall in NIST model. You're making this up. The web stiffeners would not have prevented the lateral push of the girder
 
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Christopher7 said:
Sillyness.

It is impossible to prove a negative and you know it.

We have shown where NIST lied about the stiffeners and seat width. You choose to ignore this and ask the impossible.
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No, you haven't. In fact, even assuming that the relevant section is incorrect, you have literally no way of proving it was a deliberately lie as opposed to a mistake. That's a positive claim, which you have not backed up, only handwaved about how it is "obvious".

And, of course, there's the hypocrisy of saying NIST maliciously lied in one section but was absolutely right the next. If they lied, the entire report should be in question. But it's only the parts you find inconvenient.
 
BasqueArch said:
Your'e the one that's wrong . The bottom flange did not have to fold when the girder was pushed 5.5 inches to the west for the girder to fall in NIST model. You're making this up. The web stiffeners would not have prevented the lateral push of the girder
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The NIST claim is that the flange of the girder failed in bending after the web of the girder was moved off the seat, and they were exactly right to say that if there were no stiffeners. The flange could not handle the load on the girder. It just has nowhere near the Moment of Inertia required to handle the load which would be put on it in bending in that situation.

However, the web to flange stiffeners would have provided the necessary Moment of Inertia and stiffness and then transferred the load to the girder web.

Your recent comments here make me wonder if you fully understand why an I-beam is hard to bend about the axis which is normal to the web.
 
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Tony Szamboti said:
The NIST claim is that the flange of the girder failed in bending after the web of the girder was moved off the seat, and they were exactly right to say that if there were no stiffeners. The flange could not handle the load on the girder. It just has nowhere near the Moment of Inertia required to handle the load which would be put on it in bending in that situation.

However, the web to flange stiffeners would have provided the necessary Moment of Inertia and stiffness and then transferred the load to the girder web.

Your recent comments here make me wonder if you fully understand why an I-beam is hard to bend about the axis which is normal to the web.
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Really? lets see your math............list all assumptions and show working.:rolleyes:

If you can't then we can safely assume its just something else plucked out of your behind.
 
Christopher7 said:
gerrycan, Tony and I have shown you the drawings but you refuse to see.

Drawing 1091 shows the seat (pf) was 1' 0" and drawing 9114 shows the stiffeners.
http://www2.ae911truth.org/downloads/NIST_WTC7_FOIA_11-209.zip

http://img717.imageshack.us/img717/4952/seatatcolumn79.jpg

http://img853.imageshack.us/img853/9758/col79stiffenerse.jpg
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No wonder it failed. I had the same problem. You guys need to take some structural engineering courses and work in the field. You have nothing, and that is why you laypeople are unable to publish your findings in a reality based journal.

Your CD fantasy is not coming true with weak attacks on NIST. You have no evidence for CD, the only thing to do is attack NIST's probable collapse. Probable? lol, you are attacking something which might not be the cause. This is classic failure to achieve a goal, worse, you never set a goal.

Publish or perish. Do it. Proving a probable collapse is impossible is stupid. Prove your claims, stop worrying about NIST. Who needs NIST to know WTC 7 failed in fire? You can't get past the idiotic claim of CD.

As you guys attempt to do structural engineering, if right, CD remains a fantasy. WTC 7 still failed due to fire, flight 93 was downed by passengers, and flight 77 still impacted the Pentagon. 19 terrorists did 911, no one planted themite, and you guys still can't do engineering to save your fantasies on 911. At least we can type/post while watching Columbo in-between mowing the lawn and building silent computers... not all is lost

Good luck publishing this stuff.
 
Tony Szamboti said:
The NIST claim is that the flange of the girder failed in bending after the web of the girder was moved off the seat, and they were exactly right to say that if there were no stiffeners. The flange could not handle the load on the girder. It just has nowhere near the Moment of Inertia required to handle the load which would be put on it in bending in that situation.
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"NIST claim is that the flange of the girder failed in bending after the web of the girder was moved off the seat"
Where does NIST say this.

However, the web to flange stiffeners would have provided the necessary Moment of Inertia and stiffness and then transferred the load to the girder web.

Your recent comments here make me wonder if you fully understand why an I-beam is hard to bend about the axis which is normal to the web.
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Because it's the strong axis, higher MOI. What's your point re the girder failure.
 
GlennB said:
I too can find no reference to this. Just stuff like "loss of vertical support occurred when the beam or girder walked off the bearing seat or when the bearing seat failed"

http://en.wikipedia.org/wiki/Iridium#cite_note-kirk-pt-41
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GlennB, you and BasqueArch need to take a look at NIST NCSTAR 1-9 Vol. 21 page 527 and note that they use the phrase "A girder was considered to have lost vertical support when its web was no longer supported by the bearing seat".

So they claim the girder failed as soon as the web wasn't over the seat, meaning the flange could not support the load on the girder without the web. They would be right about that if the girder web could have been pushed beyond the seat and there were no flange stiffeners.

However, there are two problems here.

1. They needed to push the girder at least 6 inches to get the web beyond what we now know was a 12 inch wide seat vs. the previously claimed 11 inches wide, and the maximum expansion they can get is 4.75 inches at any temperature due to sagging limiting expansion.

2. The above is if there were no flange stiffeners, but we now know from recently released drawings that there were flange stiffeners, which NIST did not include in their analysis, and analyses show these stiffeners would have prevented flange failure if the web wasn't over the seat.

The entire situation is utterly impossible and it really isn't hard to understand.
 
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sheeplesnshills said:
Really? lets see your math............list all assumptions and show working.:rolleyes:

If you can't then we can safely assume its just something else plucked out of your behind.
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You really need to calculate it for yourself since you don't seem to believe me.

If you have any idea of how to analyze the stress on a weld you should be able to do it with the information on this site

http://www.roymech.co.uk/Useful_Tables/Form/Weld_strength.html

Bear in mind that there were 5/16" fillet welds on both sides of the 18" height of the 3/4" thick stiffener at the web and 3/8" fillet welds on both sides of the 5.485" width of the stiffener at the flange, as shown on Frankel Steel drawing 9114.

The floor loads on the girder would have been about 50% of the 45 x 53 foot area east of it and about 25% of the similar sized area west of it. One end of the girder handled half of that load. So you can use 37.5% of the 45 x 53 foot area and a floor load of 125 psf maximum for the load on that end of the girder.

I am sure you will find that the stiffener design was more than sufficient to keep the flange from failing if the web was not over the seat.

I'll give you a hint: The resultant stress on the welds at the web from the combined vertical shear and bending would have been less than 8,000 psi. E70 weld metal can take 70,000 psi, and the parent material had a tensile yield strength of about 42,000 psi. Shear yield strength of a ductile material is about 57.7% of tensile yield strength, so the parent material wouldn't have sheared at less than about 24,000 psi and the stress there would have been a little less than 8,000 psi as the shear area is a little larger on the leg of the fillet vs. the throat (which is used for the weld).
 
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GlennB said:
I too can find no reference to this. Just stuff like "loss of vertical support occurred when the beam or girder walked off the bearing seat or when the bearing seat failed"
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I had no trouble finding it.
1-9 Vol.2 pg 448
Walk-off failure of beams and girders was defined to occur when ... (2) the beam or girder was pushed laterally until its web was no longer supported by the bearing seat. Gravity shear loads in a beam were transferred to the bearing seat primarily in the proximity of the web on the bottom flange. Therefore, when the web was no longer supported by the bearing seat, the beam was assumed to have lost support, as the flexural stiffness of the bottom flange was assumed to be insufficient for transferring the gravity loads.
 
Christopher7 said:
I had no trouble finding it.
1-9 Vol.2 pg 448
Walk-off failure of beams and girders was defined to occur when ... (2) the beam or girder was pushed laterally until its web was no longer supported by the bearing seat. Gravity shear loads in a beam were transferred to the bearing seat primarily in the proximity of the web on the bottom flange. Therefore, when the web was no longer supported by the bearing seat, the beam was assumed to have lost support, as the flexural stiffness of the bottom flange was assumed to be insufficient for transferring the gravity loads.
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According to NIST what was the chain of events after this "failure?"
 
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