29 Structural & Civil Engineers Cite Evidence for Controlled Explosive Demolition

[FineWine]

Hogwash. Your superior attitude is just that, attitude.
The facts I have stated are self evident.

You are trying to say that the columns in Group 7 could deflect laterally despite the FACT that they are surrounded by slabs on every floor. That's BS.


Which has nothing to do with the point we are discussing.

Please, they prevent the columns from moving laterally, independently.

We are not talking about the collapse, we are talking about the damage supposedly caused by the debris impact 7 hours earlier.

You know nothing and you can't learn. Please shut up.

 

[Grizzly Bear]

[qimg]http://img40.imageshack.us/img40/41/floor13debrisdamage.jpg[/qimg]

[qimg]http://img6.imageshack.us/img6/2838/floor13girderdamage.jpg[/qimg]

If you know how to draw a force diagram I encourage you to do so. If you know how to do it correctly you should be easily able to determine how much floor area would have had to have been supported by columns as some buckled and by extension how much a particular column would have been expected to carry. Or would you rather me draw you a pretty picture to give you an idea? I'm more concerned with addressing the paper described in the OP, and I think the response addresses the essential point more than sufficiently.

 

[Norseman]

At JREF, the plain truth is considered crap an sophistry is considered to be the truth.

I will respond to your very long post in small sections.

You will not respond to a few simple facts that you cannot refute or deal with. No one here is willing to challenge these facts directly because you can't:

The force of the falling debris was primarily downward.

The floor to column/girder connections on the south side of Group 8 would be bent downward. NIST says these connections were not damaged but the girder-to-column connections in Group 7 were damaged. This is impossible.

The damage was much more extensive on floors 8 & 9 yet NIST does not say that there was damage to any girder-to-core column in Group 7 on these floors. This is not possible if there was damage to girder-to-core column connections in Group 7 on floor 13.

This damage to the south wall could not cause girder-to-core column in Group 7. NIST does not even attempt to explain how the force skipped over the floor connections on the south side of group and caused damage to the girder-to-core column in Group 7. They just say that their computer model shows that it did. A computer model can be made to produce any results they want. This result is not possible.

[qimg]http://img40.imageshack.us/img40/41/floor13debrisdamage.jpg[/qimg]

[qimg]http://img6.imageshack.us/img6/2838/floor13girderdamage.jpg[/qimg]

May I remind you of my post #1125. So once again in more detail.

On PDF page 133 in NIST NCSTAR 1-9A NIST writes:

Damage to the western core developed early in the initiatialization process as a result of the WTC 1 debris impact damage. In the model, the debris damage was instantanously applied to approximate the actual dynamic event. This damage application resulted in a sudden redistribution of loads and displacements within the structure.

It was the redistribution of gravitational of loads and the following displacement that caused the damage around column Group 7 in the computer model. This is explained throughout NIST NCSTAR 1-9A, you need to take a closer look at that report in its entirety C7.

And as I have earlier pointed out to you C7, NIST concluded in NIST NCSTAR 1-9 Vol 2 page 606 (pdf 268):

For the no debris impact scenario, the horizontal progression of column failures occurred in order from east to west after collapse initiation (i.e. buckling of Column 79) and the vertical progression failures on the east side. This scenario matched the observations where the screenwall on the roof fell downward before the west penthouse. This suggests that the damage scenario that was imposed in the best estimate analysis was slightly more severe than actually occurred.

In other words, NIST is telling you that the damage around column Group 7 likely was not there in the real world event.

In other words you are attempting to kick in open doors here C7, though for the wrong reasons.

 

[triforcharity]

You did not read post 1162:
"The beam to column connection on the south side of column 63 is a STC [seated connection, 1-9A pg 25] and the girder-to-column connection on the north side is a K3 [knife connection, 1-9A pg 24]. The girder-to-column connection on the south side of column 62 was a K3 and on the north side a K4. So how does a connection with 4 bolts remain intact while breaking 3 girder-to-column connections with a total of 10 bolts?"

http://www.internationalskeptics.com/forums/showthread.php?postid=4879982#post4879982

The NIST claim that the debris damage from WTC 1 caused damage to connections in the middle row of core columns without causing damage to the connections in the south row is absurd.

The NIST claim that the debris damage from WTC 1 caused damage to connections in the middle row of core columns on floor 13 without causing similar damage on floors with greater debris damage is absurd.

You guys will believe anything NIST says no matter how absurd.

So, just because it has more bolts, automatically means it is stronger?? Not preticulary true. Smaller bolts perhaps?? Different types of welding, thicker plates, etc. etc. etc.

Is a toe nail with two 16 D nails stronger than nailing from above with 3 8D nails?? Of course it is. You get my drift sir??

 

[Christopher7]

There seems to be a lack of appreciation for how ‘empty’ these buildings were; the toppling behavior that these individuals expect to have happened is impossible. There are two major criteria required in order for anything to topple over:

• The center of gravity must move outside the bottom supports.

• False. The center of gravity need only move off center to exert more downward force on the tilt side causing that side to collapse faster and thereby increasing the tilt.

This double talk also ignores Newton's first law.
An object in motion will remain in motion until acted upon by an unbalanced force.

The top of the south tower was falling to one side. It would continue falling to one side unless some external force were applied to resist this motion. Since no force could be applied to the falling top block, the only possibility is that all the support on the high side was remove with explosives.

Please don't hand me that crap about your expertise. You are just repeating the disinformation double talk that tries to tap dance around the law of gravity and Newtons first law.

 

[triforcharity]

Holy crap, I know this is completely off topic, but here it goes.

When you tilt something, the exterrior of that object has to be able to support ALL of the weight of that ENTIRE object. The exterrior columns couldn't support it, neither could the floor below. This is why when it started collapsing, it did not continue to faall over. Its not a lego house. Its a 64,000,000 pound object. There is not much in that building that could have supported that much weight. Now, if your head was there, it might have held it. Considering how hard it is........

 

[Grizzly Bear]

</nevermind>

 

[Christopher7]

I'm kind of curious why the discussion is with the debris damage anyway. Since the debris damage from tower one's collapse ultimately wasn't a significant determining factor in the outcome.

Wrong!
You can't refute the facts I listed so now you say it's not important. The convenient timing of the collapse of Group 7 was essential or NIST would not have lied about it.

Without this early collapse of Group 7, the collapse of the screenwall and west penthouse would have taken 8 to 10 seconds to progress from east to west.

NIST stated that the failure of the screenwall and west penthouse were simultaneous.
NIST Appendix L pg 33 [pdf 37] - see also: Timeline chart on pg 27

"The simultaneous failure of screenwall and west penthouse structures"

NIST also admitted that even with the early collapse of Group 7 their scenario did not match the observed event.


NCSTAR 1-9 Vol.2 pg 612 [pdf 274]
"The results of this scenario were consistent with the observations except that

the screenwall on the roof fell downward before the west penthouse."

When the result of a scenario does not match the observed collapse, that scenario must be scrapped and a new scenario must be formulated.

It was a progressive east to west failure of the interior structure... damage to the columns in question seems like a rather moot point in this discussion other than the fact that it made it easier for them to fail when the collapse reached it.

You have not been paying attention. Group 7 supposedly collapsed BEFORE the horizontal collapse got to it.

Having no rebuttal, you will hand wave the facts and/or violate Rule 12.

 

[triforcharity]

Ok, so, just because the screen wall fell at a different time in the models than in actuality, that makes the WHOLE THING FLAWED??? That rediculous at best. Now, I could understand if the model made the S. Penthouse lift off into a low orbit, but it didn't. A screen wall (Do you even know what this is BTW?) fell at a different time than it did in actuality is moot. The global collapse STILL HAPPENED. That is why there is a certain amount of error in ANY investigation of this sort. There are numerous variables in a building collapse that must be accounted for. If you get 1,999 out of 2000 correct, than I would say that the conclusion that they come to is pretty accurate.


Can one of the engineers confirm what I have written is correct, just for my own benefit?? Thanks guys.

 

[Christopher7]

Read criteria #2 of response (1) as well as response (21). If you feel that the response to their paper doesn't correctly address their claims then consider spending an extended amount of time reading it, and looking to see what's wrong with it.

1) #2 A support point has to EXIST. In other words you have to be able to ‘bend’ the building far enough to get the center of gravity displaced that far WITHOUT the building collapsing first. A tilt of about 45 degrees would be required to translate the CG this far outside the outer edge of the building. Think about how the supports would have to react for this to happen; how in which these columns would have to compress and expand for this to happen. The problem was, LONG before the top could tilt that far, the columns below buckled.

This second part is wrong for the same reason the first part was wrong.
Of course the top part won't fall off the lower part until it reaches 45 degrees but once the tilt had started it would continue to increase as more weight was exerted on the tilt side and less on the high side.

(21)
[The upper section] began tilting toward the damage zone, and then suddenly dropped straight down

"You need a fulcrum to continue a rotational movement."

Not so. The tilt side will crush faster that the high side because of the increasing downward force. There is no fulcrum involved. The top will obey Newton's first law and continue to fall to the side until it falls off the side of the lower portion of the building.

 

[Christopher7]

Ok, so, just because the screen wall fell at a different time in the models than in actuality, that makes the WHOLE THING FLAWED???

YES!

If the end result of a scenario doesn't match the actual collapse, then it does not explain the collapse and a new scenario must be formulated. This is the scientific process.

A screen wall fell at a different time than it did in actuality is moot.

Wrong. The screenwall is not the point. It's the fact that the core columns collapsed simultaneously and not progressively. The NIST model does not do this because a progressive collapse cannot result in a simultaneous collapse of 6 rows of columns.

 

[Newtons Bit]

Hogwash. Your superior attitude is just that, attitude.
The facts I have stated are self evident.

You are trying to say that the columns in Group 7 could deflect laterally despite the FACT that they are surrounded by slabs on every floor. That's BS.


Which has nothing to do with the point we are discussing.

Please, they prevent the columns from moving laterally, independently.

We are not talking about the collapse, we are talking about the damage supposedly caused by the debris impact 7 hours earlier.

It's like arguing with a brick wall. Anymore discussion is pointless. You're not going to change your mind, you're not going to look up anything, you're not going to educate yourself. You have an attitude of "SPOON FEED ME OR INSIDE JOB!" and it's frankly, boring.

 

[triforcharity]

Ok, so we are back to this BS nonsense again.

Chris, the time it took for the interrior columns to completely collapse was what?? Page 261 (pdf) of NCSTAR 1-9 Vol 2 Total time?? from Column 79 failure is about 15.3 seconds.



Now, how many interrior columns did WTC 7 have?? 24 total.

Now, if we use SECOND GRADE MATH we get an average of 1.5 columns fail per second. (Rounded down to 16 seconds)

So, why is it so hard to imagine that a bunch of columns, ALL TIED TOGETHER fell simultaniously?? Because ChrisPhysics say it can't happen??? Right.....


Collapse investigation is NOT an EXACT science. It has an inherant degree of error. Now, again, if say there were 5000 (low ball figure, its most likely more like 10,000,000 or so) points that they had to replicate, and they got 4999 RIGHT, that is accurate to within .0002%. I'd say that about as close to perfect as you are going to get as far as this is concerned.

So, what is a screen wall Mr. Carpenter??

 

[Christopher7]

It's like arguing with a brick wall.

Tell me about it.

You're not going to change your mind, you're not going to look up anything, you're not going to educate yourself.

Nothing could be further from the truth. I have looked at all relevant information, and responded to it.

You cannot refute my last two posts so you ignore it and bad mouth me.

Your fanatic denial or avoidance of anything that refutes the OCT is testimony to your character and purpose.

 

[Grizzly Bear]

Ok, so we are back to this BS nonsense again.

Chris, the time it took for the interrior columns to completely collapse was what?? Page 261 (pdf) of NCSTAR 1-9 Vol 2 Total time?? from Column 79 failure is about 15.3 seconds.

He's been using the Appendix L report like a final document for months... Apparently unfinished research is better suited than finished for him...

 

[Christopher7]

Chris, the time it took for the interrior columns to completely collapse was what?? Page 261 (pdf) of NCSTAR 1-9 Vol 2 Total time?? from Column 79 failure is about 15.3 seconds.

Now, how many interrior columns did WTC 7 have?? 24 total.

The screenwall and west penthouse were supported by columns 58-75 [18 columns - 6 north-south rows]
According to the time line, it took about 1 1/2 to 2 seconds for the collapse to progress from one row to the next. It would take 8 - 10 seconds for the progressive collapse to progress across the core.
That is not what happened and therefore the NIST scenario does not explain the collapse.

This is not a minor detail, it is a major difference.

Time line using data from NCSTAR 1-9 Vol.2 pages 579-585 [pdf 241-247]
-1.3s Column 79 failed [Group 1]
-0.5s Column 80 fails [Group 1]
-0.5s Column 66 fails [Group 8]
~0.0s Column 81 fails [Group 1]
0.0s Kink in penthouse visible
1.3s Columns 77 & 78 failing [Group 2]
2.5s Columns 77 & 78 fail [Group 2]
3.5s Column 76 fails [Group 2]
4.3s Columns 59, 62, 65 & 68 fail [Group 7] G6 & G8 loading
4.5s Columns 73 - 75 fail [Group 3]
5.3s Columns 60, 63 and 69 fail [Group 8]
5.3s Column 58 failed [Group 6]
5.5s Group 3 still failing
6.3s Columns 70 - 72 failing [Group 4]
6.3s Columns 61, 64 and 67 failed [Group 6]

So, why is it so hard to imagine that a bunch of columns, ALL TIED TOGETHER fell simultaniously??

They did . . . . but that was not the result of the NIST scenario.

 

[Christopher7]

He's been using the Appendix L report like a final document for months... Apparently unfinished research is better suited than finished for him...

The data in the NIST L report did not get stale or go out of fashion. The screenwall and west penthouse fell simultaneously. That is a FACT. FACTS do not change.
Your attempt to suggest that this FACT is no longer valid, is a transparent disinfo tactic.

 

[tfk]

We're all entitled to laugh at the idiocy of Heiwa, Bill Smith, and Christopher7, but ignorant, obtuse, agenda-driven fools are often capable of great evil. I think of such people as dangerously stupid.

Good thing, then, that the twoofers seem congenitally lazy, no?!!

Keep 'em (mostly) from causing too much mischief.

Tom

 

[H'ethetheth]

I'm trying to figure out what the hell it is Christopher is trying to prove here.

Did NIST model explosives in columns 59, 62 and 65 and try to cover it up?

Should WTC have stopped collapsing after half of the interior ended up in a pile in the lobby?

Did the evil government know in advance where fires would burn and debris would fall, so that all they had to do was blow up columns 59, 62 and 65, because that would ensure a total collapse (the only disadvantage being that the building would collapse at freefall for a while but who would notice that, right)?

Did NIST make an error (perhaps "conveniently") in the model, e.g. did they forget to add floor elements, or tighten some virtual bolts perhaps? Did they do this because otherwise the simulation wouldn't have matched the real thing?

 

[tfk]

I'm trying to figure out what the hell it is Christopher is trying to prove here.

As concise as I can put it...

He is trying to show that "dogged ignorance and empty bluster" can level the playing field with "impatient knowledge & experience".


Tom

PS. He's wrong, of course...