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'What about building 7'?

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Your mistakes have undermined your argument.
Which argument was undermined by my mistakes? My main argument has been all the time that NIST was consistent in their assessments and that the errors that gerrycan claims to have found are not such. Which part of the mistakes I have admitted undermines that argument?


You have failed to show where Gerry has made a mistake, or mistakes, that undermines his argument.
You haven't been paying attention. I did, repeatedly.

For instance, in post #3404 I pointed out how the beams and girders that gerrycan mentioned did ABSOLUTELY NOTHING to restrain the column the way he said they did.

Or in the other instances where he said the column was restrained, I showed it wasn't.

Be more attentive if you want to make these claims.


Interesting approach.

Gerry's quest is to show that serious errors in your NIST-based argument make it critically flawed, while you appear to be more interested in using the NIST's reputation as the basis for your argument that regardless of those errors, the NIST must be right.
No, I'm pointing out that those that gerrycan says are errors are not, and that NIST is consistent. Not sure of this is a problem of attention or of understanding on your side.
 
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Which argument was undermined by my mistakes? My main argument has been all the time that NIST was consistent in their assessments and that the errors that gerrycan claims to have found are not such. Which part of the mistakes I have admitted undermines that argument?



You haven't been paying attention. I did, repeatedly.

For instance, in post #3404 I pointed out how the beams and girders that gerrycan mentioned did ABSOLUTELY NOTHING to restrain the column the way he said they did.

Or in the other instances where he said the column was restrained, I showed it wasn't.

Be more attentive if you want to make these claims.



No, I'm pointing out that those that gerrycan says are errors are not, and that NIST is consistent. Not sure of this is a problem of attention or of understanding on your side.

He was also mistaken about which floors to look at for connection failures on the girders between C76 - C79. As Oystein pointed out, they failed on 10 - 12 in case B. On 13 the failure at C79 was on the north girder connection, and the south girder buckled.

He also appears to continue to get girders and beams mixed up.
 
They were off by an inch.

And the stiffners plates, he has not shown how it is impossible for the building to fail with factors such as fire/buckling/weight distribution etc. if an inch is enough to hold the build together why make them12 inches.

If it were a pristine building he may have a point.
 
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I've been lurking on this for a while and not having an engineering background, need a bit of clarification on a point.

It's not hard to image this collapse in the 7WTC design

The core region collapse first... it doesn't topple it collapse down.If columns get pushed out of alignment... somehow... no columns need to be crushed and the structure above has essentially no resistance. It plummets down and it severs connections to floor beams.

This leaves the floors and the moment frame at the perimeter. The latter is supported in very unorthodox manner. 80% of the north side was on the end of cantilevers... nothing structural axially linking that the the foundations.

Both the east and west sides were braced frames - truss structures with only 4 vertical columns. The south side had a multistory lobby with no lateral support for most of the width. The braced frames apparently acted like membranes and folded in when the core collapsed and their interconnecting beams pulled them inwards.

Essentially there was a rapid progressive destruction of the structure below flr 7 ... and the relatively few columns that were there. The failures left the core destroyed and the rest came down... last to fall was the exterior moment frame which has the structure pulled out (inward) from under it.

One failure caused adjacent failures and the pace picked up very rapidly and then there was not enough capacity and it let loose.

All this makes sense. Is this the way that buildings in built up areas of this type are designed to minimise damage to the surrounding area in case of disaster?
 
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He also appears to continue to get girders and beams mixed up.
I don't mind much about that point specifically. Even NIST called a girder 'beam' in one instance:

The top clip angle used in STC connection at Column 79 and Column 81 was weak in tension and needed to be explicitly represented in the connection model. Therefore, the failure of the connection was governed by tension failure of the top clip angle or bolt shear followed by beam walking-off the seat and loss of vertical support.

(though it's arguable whether they referred to the 'beam' element of ANSYS in this instance).

The problem is that it may be a source of misunderstandings. NIST mostly refers to the beams that are not girders as "floor beams", to eliminate ambiguity I guess.
 
I don't mind much about that point specifically. Even NIST called a girder 'beam' in one instance:

The top clip angle used in STC connection at Column 79 and Column 81 was weak in tension and needed to be explicitly represented in the connection model. Therefore, the failure of the connection was governed by tension failure of the top clip angle or bolt shear followed by beam walking-off the seat and loss of vertical support.

(though it's arguable whether they referred to the 'beam' element of ANSYS in this instance).

The problem is that it may be a source of misunderstandings. NIST mostly refers to the beams that are not girders as "floor beams", to eliminate ambiguity I guess.

By getting them confused, he failed to communicate that he was talking about a girder to the west of C79, and not a beam.

I myself have gotten them confused. I will admit my errors in that regards.
 
By getting them confused, he failed to communicate that he was talking about a girder to the west of C79, and not a beam.

I myself have gotten them confused. I will admit my errors in that regards.
That speaks well of your honesty in the debate.
 
A good discussion between a bona-fide "truther" and a well-informed "debunker" is a very rare thing in this sub-forum these days.

Wish it could maintain focus, which, at this time, is the results of the ANSYS sim.

I kindly ask everyone not to derail the discussion by either moving goal posts, or responding in any way at all to obvious trolls. Thank you!
 
A good discussion between a bona-fide "truther" and a well-informed "debunker" is a very rare thing in this sub-forum these days.

Wish it could maintain focus, which, at this time, is the results of the ANSYS sim.

I kindly ask everyone not to derail the discussion by either moving goal posts, or responding in any way at all to obvious trolls. Thank you!
+1
 
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