Total Building Collapse from a Single Column Failure

[JayUtah]

The NIST WTC 7 report has been proven to have fatal flaws in their collapse initiation hypothesis due to the omission of pertinent structural features which make that hypothesis impossible.

Same old, same old.

It is time to stop pulling tantrums and making incorrect claims like Animal did here, and demand that the agency...

Get over yourself. When you start behaving like a real engineer instead of a public activist, then you can make such demands. Better yet, publish your findings in a prominent peer-reviewed structural engineering journal. Then -- and only then -- can you make authoritative pronouncements of what has been proven.

 

[JayUtah]

None of your business.

Yeah, it really is.

What do you do for a living?

 

[JayUtah]

...NIST tend to call plates that are added to the side of a column "column side plates". LMAO. Priceless.

Actually NIST calls them "side cover plates."

But here's the rub. You told us they would prevent the girder from rotating. But as you can tell in the plan they can do no such thing. Further, if they prevent the girder from rotating to walk off the seat in that fashion, they also prevent the girder from assuming the position you indicate in your annotation of the NIST drawing, showing the deforming girder flange.

Can you explain that?

 

[Tony Szamboti]

Same old, same old.

Same old correct comment in that the NIST WTC 7 collapse initiation hypothesis is impossible with the omitted structural features included and the correct seat width.

Get over yourself. When you start behaving like a real engineer instead of a public activist, then you can make such demands. Better yet, publish your findings in a prominent peer-reviewed structural engineering journal. Then -- and only then -- can you make authoritative pronouncements of what has been proven.

It is not about me, it about the right thing being done and it has not been thus far.

As far as publishing something on it, that is not necessary to show a public agency is incorrect. The release of the drawings showed the NIST WTC 7 report omitted pertinent structural features and distorted the seat width. That is why a complaint was sent to the DoC Inspector General. NIST needs to respond to that complaint not something in a journal somewhere.

 

[gerrycan]

Actually NIST calls them "side cover plates."

Clearly.

 

[gerrycan]

Actually NIST calls them "side cover plates."

See above.

But here's the rub. You told us they would prevent the girder from rotating.

I think that the girder would potentially be trapped by them if it could be moved far enough to come into contact.

Further, if they prevent the girder from rotating to walk off the seat in that fashion, they also prevent the girder from assuming the position you indicate in your annotation of the NIST drawing, showing the deforming girder flange.

Can you explain that?

Can I explain how a girder is pushed further than is physically possible by expanding beams? Of course not, and neither can you, or NIST.
Maybe you could explain how near to the column face the girder would be once it is heated in NISTs analysis, and how far over the edge of the girder side the plates extend.

 

[JayUtah]

Clearly.

Okay, it's "side cover plates" in the other diagrams they prepared from the shop drawings. They're inconsistent then.

Any answer to my real question?

 

[JayUtah]

I think that the girder would potentially be trapped by them if it could be moved far enough to come into contact.

That's not my question. Do you agree that the same situation, if presented, would also prevent the flange deformation you illustrated?

 

[gerrycan]

Okay, it's "side cover plates" in the other diagrams they prepared from the shop drawings.

Show me. I am not doubting you, I am just interested.

 

[gerrycan]

That's not my question. Do you agree that the same situation, if presented, would also prevent the flange deformation you illustrated?

Moot. The stiffener plates would prevent that.

 

[JayUtah]

Moot. The stiffener plates would prevent that.

You're dodging the issue. You illustrated your interpretation of the suggested failure mode (i.e., by plastic deformation of the girder flange) without regard to the horizontal extension of any side [cover] plates. You didn't, for example, argue that the girder could not have displaced laterally enough because of these alleged features. Indeed, if the plate extension could have kept the web properly placed atop the seat, then the stiffener could be obviated.

Only when a different failure mode was presented did you suddenly consider the plates to be a limiting feature. And you presented that argument without revising yours.

In fact you cannot substantiate that any feature of the column would have prevented girder rotation. And this failure mode is not alleviated by any transverse stiffening.

 

[JayUtah]

Show me. I am not doubting you, I am just interested.

E.g., Fig 8-21 NCSTAR 1-9 p. 349

 

[Tony Szamboti]

Show me. I am not doubting you, I am just interested.

NIST does call the plates used to build up an H column both "side plates" and "side cover plates". A search of NIST NCSTAR 1-9 volumes 1 & 2 for both terms separately will show they used both.

Either term is correct.

 

[Tony Szamboti]

You're dodging the issue. You illustrated your interpretation of the suggested failure mode (i.e., by plastic deformation of the girder flange) without regard to the horizontal extension of any side [cover] plates. You didn't, for example, argue that the girder could not have displaced laterally enough because of these alleged features. Indeed, if the plate extension could have kept the web properly placed atop the seat, then the stiffener could be obviated.

Only when a different failure mode was presented did you suddenly consider the plates to be a limiting feature. And you presented that argument without revising yours.

In fact you cannot substantiate that any feature of the column would have prevented girder rotation. And this failure mode is not alleviated by any transverse stiffening.

The five beams framing into the girder from the east, with each having a 20 inch long six bolt connection to it, prevent the girder from rotating. Lateral torsional buckling of the girder is not a plausible failure mode with the beams connected to it every 8 to 9 feet along its 45 foot length.

 

[JayUtah]

Show me. I am not doubting you, I am just interested.

I can't speak for Animal, but I think you misled us -- this time unintentionally.

In some construction you can extend the plates on the side of an H-column significantly in some places in order to create gusset plates or provide additional horizontal bracing at connections. But in most cases you extend the plate only far enough to allow a fillet weld. This was the case in WTC 7. In that case it's simply absurd to suppose that this would have any role in limiting lateral motion with any structural significance.

Hence when you implied that the feature in question would have limited the girder rotation, the only feature possible in any of the relevant construction would be the flange of the column if the column were left as an H-column, as for the exterior columns. I assumed you misspoke, meant the flange, and simply called it by its wrong name. It's clear now you intended a different argument than what we all thought and were using defensible terminology for that argument. I apologize for the misunderstanding.

 

[JayUtah]

The five beams framing into the girder from the east, with each having a 20 inch long six bolt connection to it, prevent the girder from rotating. Lateral torsional buckling of the girder is not a plausible failure mode with the beams connected to it every 8 to 9 feet along its 45 foot length.

Discussed above.

 

[Animal]

I can't speak for Animal, but I think you misled us -- this time unintentionally.

In some construction you can extend the plates on the side of an H-column significantly in some places in order to create gusset plates or provide additional horizontal bracing at connections. But in most cases you extend the plate only far enough to allow a fillet weld. This was the case in WTC 7. In that case it's simply absurd to suppose that this would have any role in limiting lateral motion with any structural significance.

Hence when you implied that the feature in question would have limited the girder rotation, the only feature possible in any of the relevant construction would be the flange of the column if the column were left as an H-column, as for the exterior columns. I assumed you misspoke, meant the flange, and simply called it by its wrong name. It's clear now you intended a different argument than what we all thought and were using defensible terminology for that argument. I apologize for the misunderstanding.

I agree - I was under the same impression.

 

[Tony Szamboti]

I can't speak for Animal, but I think you misled us -- this time unintentionally.

In some construction you can extend the plates on the side of an H-column significantly in some places in order to create gusset plates or provide additional horizontal bracing at connections. But in most cases you extend the plate only far enough to allow a fillet weld. This was the case in WTC 7. In that case it's simply absurd to suppose that this would have any role in limiting lateral motion with any structural significance.

Hence when you implied that the feature in question would have limited the girder rotation, the only feature possible in any of the relevant construction would be the flange of the column if the column were left as an H-column, as for the exterior columns. I assumed you misspoke, meant the flange, and simply called it by its wrong name. It's clear now you intended a different argument than what we all thought and were using defensible terminology for that argument. I apologize for the misunderstanding.

The 26 inch wide side plates on column 79 were symmetrically located and extended 1.79 inches past the flanges of the column on each side, as a W14 x 730 is 22.42 inches deep from flange face to flange face.

 

[gerrycan]

You're dodging the issue.

Not at all.

You illustrated your interpretation of the suggested failure mode (i.e., by plastic deformation of the girder flange) without regard to the horizontal extension of any side [cover] plates.

The illustration demonstrates that the girder was deemed to have failed when it reached that point. It illustrates that point.

You didn't, for example, argue that the girder could not have displaced laterally enough because of these alleged features.

Correct. I didn't.

Indeed, if the plate extension could have kept the web properly placed atop the seat, then the stiffener could be obviated.

And if the girder could have been pushed that far, this would maybe not be hypothetical.

Only when a different failure mode was presented did you suddenly consider the plates to be a limiting feature. And you presented that argument without revising yours.

I didn't suddenly consider anything. I don't think that the beam would rotate to a degree that would make it relevant. If you do, you need to show this and I will respond when you do.

In fact you cannot substantiate that any feature of the column would have prevented girder rotation. And this failure mode is not alleviated by any transverse stiffening.

Which NIST mode of failure are you talking about? The rock off theory or the pushed beyond the seat theory? Which one of these are you hanging your hat on now?

 

[JayUtah]

The illustration demonstrates that the girder was deemed to have failed when it reached that point. It illustrates that point.

A point, according to you, that no seated connection could ever have attained due to interference with side plates.

And if the girder could have been pushed that far, this would maybe not be hypothetical.

But at present it is hypothetical.

I don't think that the beam would rotate to a degree that would make it relevant. If you do, you need to show this and I will respond when you do.

No. You're the one saying this allegedly crucial connection could not have failed when the NIST model suggested it did. You have the burden to prove this for all failure modes, not just the one NIST contemplated elsewhere in the report, and not just one or two other straw men you can think of. You've already accepted the burden to rule these out because you've made several posts already along those lines. So I think you can go ahead and keep bearing that burden.

In the larger sense, I remind you that you're accusing people of deliberate professional malfeasance and gross misrepresentation. If there is any question who has the burden of proof in any fine question attached to that, I remind you of the gravity of your claims and their extraordinary nature.