Acceleration of the falling top blocks.

[ergo]

The funniest part of this post. Everything he said is true*. He just doesn't connect it as a system that allowed the building to stand.

This makes no sense. You're the one who just tried to assert that the floors hold the building up.

 

[thedopefishlives]

This makes no sense. You're the one who just tried to assert that the floors hold the building up.

No. The floors hold the building TOGETHER. As in, laterally. Exactly what you just asserted. What you don't comprehend is that the lack of lateral stability after the floors disconnected is what caused the core columns to fall. The columns by themselves are way too tall and way too narrow to stand on their own without the bracing support provided by the floors.

 

[ergo]

No. The floors hold the building TOGETHER. As in, laterally. Exactly what you just asserted. What you don't comprehend is that the lack of lateral stability after the floors disconnected is what caused the core columns to fall. The columns by themselves are way too tall and way too narrow to stand on their own without the bracing support provided by the floors.

No, that's incorrect. The core was self-supporting. It had to carry the gravity loads. Where are you getting this information from?

 

[DGM]

Are transverse trusses not bridging trusses, Mr. 25 Years in Construction?

Nope. One is used to stiffen the floor the other carries a load.

BTW I said 35 years (You can't get anything right).

Wrong about what?

That the building structure would stand without the floors.

 

[tsig]

Now they're transverse trusses. Make up you're mind.





Believe what you want to believe, you're still wrong.



What about that "cabling" of yours?

Makes sense, the building had a major hernia.

 

[DGM]

This makes no sense. You're the one who just tried to assert that the floors hold the building up.

No I didn't. I said they are part of a system that does.

 

[ergo]

No I didn't. I said they are part of a system that does.

Of course they are. The whole building is a structural system. Nothing new about that. But the core isn't going to crumble with the loss of a few floors.

 

[DGM]

Of course they are. The whole building is a structural system. Nothing new about that. But the core isn't going to crumble with the loss of a few floors.

Who said it would?

 

[DGM]

Ergo:

Quick question, Do you trust Major_Tom's work? You know he agrees with what I'm saying. His problem is with initiation not progression.

 

[ergo]

Nope. One is used to stiffen the floor the other carries a load.

Oh, I see. So one stiffens, and one carries load. So what was it you were trying to say that bridging trusses don't do here?

And what was it that you originally took issue with in my description of the floor assembly?

PS: (see what I mean by time wasting?)

 

[ergo]

Ergo:

Quick question, Do you trust Major_Tom's work? You know he agrees with what I'm saying. His problem is with initiation not progression.

You're not saying anything here, DGM. You haven't talked at all about collapse initiation or progression.

I don't know if I trust Major Tom. He doesn't answer my questions. His model is simply FEMA revamped. And that model had problems that still haven't been addressed, except for handwaves.

ETA: Having said that, I hope Major Tom will submit his thesis for engineering peer review.

 

[GlennB]

No, that's incorrect. The core was self-supporting. It had to carry the gravity loads. Where are you getting this information from?

If the core alone had been built, it would have blown over in the first serious gale. It was not "self-supporting" in any useful, real-world sense. Also the exterior columns contributed significantly to carrying gravity loads. The floors connected to the exterior, so those walls had no choice but to bear gravity loads.

 

[DGM]

And what was it that you originally took issue with in my description of the floor assembly?

What was your problem with the (often) pictured truss to column connection? You want to talk about wasting time.

 

[thedopefishlives]

No, that's incorrect. The core was self-supporting. It had to carry the gravity loads. Where are you getting this information from?

So what you're telling me is that if you string a bunch of steel columns together end-to-end, 1100 feet long, and stick one end in the ground with the other end pointing straight up, it should be able to hold itself up. I tell you what, why don't you try it and get back to me with the results.

 

[ergo]

So what you're telling me is that if you string a bunch of steel columns together end-to-end, 1100 feet long, and stick one end in the ground with the other end pointing straight up, it should be able to hold itself up.

No, that's clearly not what I'm saying, which is evident in several of my posts above. I guess this strawman signals your exit from this discussion?

 

[DGM]

What condition have I thrown in that wasn't there?

Sorry ergo, I missed this post.

The condition you throw in is the fact the floors (that you agree brace the structure) could not support the mass of the falling debris/rubble. Where do you get this idea? You seam to believe everything could be "blown" outside. What force could do this?

 

[ergo]

If the core alone had been built, it would have blown over in the first serious gale. It was not "self-supporting" in any useful, real-world sense.

It was self supporting in a very useful, real world sense. What height of stand-alone structure are you envisioning here that it would "blow over"?

 

[GlennB]

It was self supporting in a very useful, real world sense. What height of stand-alone structure are you envisioning here that it would "blow over"?

A WTC1 or 2 height.

 

[thedopefishlives]

No, that's clearly not what I'm saying, which is evident in several of my posts above. I guess this strawman signals your exit from this discussion?

No, it's not at all evident. You claim that the core should be self-supporting. The core itself is nothing but a series of tall columns. How are these columns supposed to be self-supporting? They have nothing to stabilize them laterally. As was posted above, the core by itself would've fallen over in a stiff wind. You can claim I'm aiming at a straw man all you like, but the essence of your claim is that a set of vertical columns (the core) should be able to support themselves vertically with no lateral stabilization. If I'm wrong, please tell me where you think the core columns were getting their lateral stability from, aside from the floor connections to the perimeter columns.

 

[ergo]

A WTC1 or 2 height.

Well, duh.