'What about building 7'?

[gerrycan]

"The top of the columns at floor 16 were fixed in the global x- and y- directions, to prevent lateral displacements..."

Note, only the top and bottoms were fixed in the x- and y- directions, the rest of the columns could move in all directions.

Where does it say top AND bottom?
They were free in the z axis.

 

[Ziggi]

So are you saying that NIST falsified their data and dropped the girder and its associated floor structure before it had reached the assumed walk off threshold...

Yes.

...or are you saying that the beam reached the claimed threshold but that it wouldn't have failed because of the plates?..

No it could not reach that point. But yes, even if it could have reached it, the flange would not have failed due to the plates. NIST never even showed analysis to prove that the flange would fold without the plates! It was just an assumption fed into the model.

 

[Reactor drone]

Where does it say top AND bottom?
They were free in the z axis.

Just before the bit that I quoted.

 

[Oystein]

Oystein, of course you can see.From #4052:

That´s NIST´s collapse initation story: "once the girder had been pushed...6.25 inches"

- "nitpicking" the possible expansion is how one assumption is challenged, by pointing out that the 6.25 inch expansion is not possible. NIST´s story rests on this one assumption and it stands or falls by it alone.

Well thanks for demonstrating with utmost clarity AGAIN how you have zero understanding of the big picture: That this distance of 6.25 inches is measured BEFORE the assembly is distorted and deformed by fires - before, for example, col 79 was pushed east to decrease the required walk-off distance.

Another challenge is pointing out that the missing stiffener plates which would render the 6.25 inch expansion useless.

Thanks again for demonstrating your (possibly willful) ignorance: end plates <> stiffener plates.

Both challenges refute NIST´s story.

You were wrong both times. Keep your ears and eyes shut if you want to converse this situation.

 

[Ape of Good Hope]

Give them an inch and they'll take a mile.


(and it'll be a mile in the wrong direction)

 

[Tony Szamboti]

It might be ASTM A572, but what grade?

ASTM A572 Grade 50.

Didn't you know?

 

[Spanx]

Looking on the bright side, with all the Ae911 truth experts posting on this forum we can all sleep well knowing that they are not involved in real world construction and never will be.

 

[Crazy Chainsaw]

Give them an inch and they'll take a mile.


(and it'll be a mile in the wrong direction)

Where do they get this supposed inch the columns are expanding upward with the girder as that would also be expressed in the computer model were is this ridiculously simplistic argument going except the trash bin?
The Column expansion should reduce walk off distance by about 2, 2 1/2 inches, and would have been factored into the model by the computer program.
There seems to be serious over simplification in there estimate.

 

[Grizzly Bear]

Then you declare that no matter how faulty NIST´s work is...

No, what I am saying is that the final conclusion: fire caused the collapse, is not married to the micro detail you've spent all of this time concerning yourself with. You can quote the CBTUH all day trying to point out some misunderstanding but they are quite clear that their disagreement was distinguished by the kind of failure caused by fires, rather than a disagreement on whether the fires even caused it.

You're doing exactly what Bazanto-files have done by trying to overextend their remarks.

Notice that? Hmm? Columns = plural. Specifically "internal" columns.

Fine: "Internal columns" = plural. Have a cookie

The council would benefit from a very careful study of NIST´s report with people like Tony Szamboti, and of the he missing structural features they have discovered, and of course all the evidence NIST did not mention.

EDIT: I'm sure you won't get into this because you want me and others to state definitively that we reject the fire induced collapse conclusions first based entirely on this micro detail being flawed. So sorry, but with your refusal to move further than this issue, and strategy of not defining your real conclusions (which I know already from inference) you're never going to progress this, and you're never going to validate your conclusions.

You also don't want to get into the idea of criticizing that the CBTUH and others have stated their disagreements without radically changing their agreement that the fires were to ultimate culprit of the collapse. You don't want to deal with the alternative mechanisms that THEY suggested because then it deflates the significance of the time being invested on the validity of the girder walk off as it relates to your perceived validity of the report's findings as a whole.

 

[Oystein]

(IF the 16-story FEA model would not reflect the deformations and displacements in all directions that reality necessarily must have seen, then the model is bunk from the get-go and we need not talk about any of its details at all.)

p484 NCSTAR 1-9
Only failure modes in the East side of the building were modeled and the columns in the model were fixed in the x-y axis to prevent any lateral displacement.

Seriously? Did you hope I would not open the report and read for myself??

"The top of the columns at floor 16 were fixed in the global x- and y- directions, to prevent lateral displacements..."

Note, only the top and bottoms were fixed in the x- and y- directions, the rest of the columns could move in all directions.

Where does it say top AND bottom?
They were free in the z axis.

Seriously??? You really can't read, can you? Here, let me read out p484 NCSTAR 1-9 for ya:

"Displacement Boundary Conditions

The column nodes at the base of the 16 story model were fully fixed to model the rigidity of the grillage and foundation (Chapter 2). The top of the columns at Floor 16 were fixed in the global x- and ydirections, to prevent lateral displacements, and were free in the global z-direction, to allow vertical displacement of the columns in response to gravity loads and thermal expansion. The purpose of the ANSYS model was to simulate the accumulation of local damages and failures up to the initiation of overall global collapse due to fire. The building was not expected to displace significantly in the x- and y-directions outside of the floors with no fire and there was no interaction between adjacent columns for relatively small motions in the z-direction, due to limited load re-distribution mechanisms."​

No other Displacement Boundary Conditions are mentioned, and since they explicitly state those for the bottom and the top of the 16-story assembly, I am sure you will agree with what I implied initially: the 16-story FEA model DOES reflect the deformations and displacements in all directions that reality necessarily must have seen - on all floors except the very top and the very bottom. It would help your credibility to admit that the model does indeed reflect movement of all nodes on all the relevant floors (5-13 at least) in all spatial directions. If you go on denying or ignoring this FACT, this would serve to further undermine your credibility.

 

[Reactor drone]

The council would benefit from a very careful study of NIST´s report with people like Tony Szamboti, and tof the he missing structural features they have discovered, and of course all the evidence NIST did not mention.

Exactly what benefit do you think the CTBUH would gain from the discovery of these "missing" structural features?

We know the building had them even I the model didn't and we know the building collapsed so I don't think these features are the magical anti collapse features that you seem to think they are.

 

[Ape of Good Hope]

Seriously? Did you hope I would not open the report and read for myself??



Seriously??? You really can't read, can you? Here, let me read out p484 NCSTAR 1-9 for ya:

"Displacement Boundary Conditions

The column nodes at the base of the 16 story model were fully fixed to model the rigidity of the grillage and foundation (Chapter 2). The top of the columns at Floor 16 were fixed in the global x- and ydirections, to prevent lateral displacements, and were free in the global z-direction, to allow vertical displacement of the columns in response to gravity loads and thermal expansion. The purpose of the ANSYS model was to simulate the accumulation of local damages and failures up to the initiation of overall global collapse due to fire. The building was not expected to displace significantly in the x- and y-directions outside of the floors with no fire and there was no interaction between adjacent columns for relatively small motions in the z-direction, due to limited load re-distribution mechanisms."​

No other Displacement Boundary Conditions are mentioned, and since they explicitly state those for the bottom and the top of the 16-story assembly, I am sure you will agree with what I implied initially: the 16-story FEA model DOES reflect the deformations and displacements in all directions that reality necessarily must have seen - on all floors except the very top and the very bottom. It would help your credibility to admit that the model does indeed reflect movement of all nodes on all the relevant floors (5-13 at least) in all spatial directions. If you go on denying or ignoring this FACT, this would serve to further undermine your credibility.

Now come on.

Everyone knows that 'base' and 'bottom' are two completely different things:

1. "Gerry scraped the bottom of the barrel"

2. "All Gerry's base are belong to us."

 

[Animal]

Good grief man... you didnt reverse engineer the values... i linked you to the source AND told you what my. Calcs used. I also limited the scope applicability. If you want to take those values and tell me im wrong because you're reading my intent the same way TZ et al read Bazants limiting models, then you're taking my comment waaaay too far
http://www.internationalskeptics.com/forums/showpost.php?p=9953540&postcount=997

That seems to be one of the few tactics the troofer cultists have left.
Most reality based people here talk more in generalities than in absolutes.......because of the unknown factors and the multiple variables......troofers are always seizing on statements like that as absolutes to try to "score points" in the odd belief that they will win over hearts and minds. (Repeating the same pattern over and over expecting different results......definitely crazy.)

 

[Animal]

Being no more than an intern in this discussion, watching the pros battle it out, I may be out on a limb now, but I'll say it anyway:

This is getting most silly!

On several floors, many beams, girders, columns, concrete slabs and what else have your were subject to a history of heating and cooling caused by wandering fires, right?
So hundreds of elements in that 16-story assembly that NIST considered were subject to all sorts of heat-induced contortions - expanding, contracting, bending, torquing, ... right?
Each node thus was likely to move some distances up, down, N, E, W, S by different distances at different times - right?
And those distances would not only depend on the heat-induced deformation of the elements that come together at that node, but also on the displacememts of all the neighboring nodes, which in turn are affected by displacements of nodes that they link to - right?
NIST ran an FEA with ANSYS, which resulted in such displacements of nodes - right?
Their model produced as implicit and explicit results displacements of every node at many points in time, right?
And quite generally, we do not know the values of almost all such displacements, right?
We know them neither in the NIST model, nor in the reality of the burning building, right?

So how can you pick out one single element, claim a single value of displacement or non-displacement or whatever that 1 inch is that you are talking about, and try to make us believe that somehow this particular inch makes or breaks the overall outcome of "fire induced floor failure at col. 79"? This appears to me to be exceedingly silly!

It goes even further.....
The modeling of the structure is done with static strength of materials (all being exactly as specified) as well as bolt torque, welds etc. This would not be the case in the real world

They used static loading for dead loads and combustibles.
This would not be the case in the real world

They did added elements to prevent certain structures from failing in the simulation. This was not the case in the real world

There was many objects installed not included in the model.
Things like support angles, sprinkler lines, etc all could add vertical support, lateral bracing etc in a range of a very little to a very lot which could alter when and how beams deflect, sag and buckle

They used static settings of open / closed doors in the fire simulation.This would not be the case in the real world


The list could go on and on and on. There were countless variables that were unaccounted for that could impact exactly how the failure was initiated.......from troofers to being arguing that a 1" difference invalidates the entire study and CD is the only cause goes beyond silly......it is frikkin insane.

 

[Animal]

In chapter 8,

" Note that, in the detailed finite element analyses of the 16-story ANSYS model (see chapter 11) no boundary conditions were applied to the floor slabs, and the temperatures of both the steel and concrete were derived from a thermal analysis based on fire dynamics calculations."

Wow.....talk about hamster wheeling.......even the resident carpenter gave up that dead end years ago when that little fact was brought top his attention.

It is comical that it is now being brought up again. Troofers really haven't learned anything in all these years. (But dicky gage is racking up the frequent flyer miles.....all on the backs of his adoring cultists.)

 

[WilliamSeger]

You don´t seem to understand what is being said. The problem with NIST´s girder walk off story is not only that the numbers don´t add up, not even close, but also and perhaps more importantly that NIST tried to hide the problem.

That's the kind of reasoning that often results from starting with the conclusion and then hunting for confirming evidence. You don't seem to understand how weak your evidence sounds to people who prefer to go the other way.

Then you declare that no matter how faulty NIST´s work is, that its conclusion about column 79 failure as the initating event must be true...

Are you feeling so vulnerable that you feel it might help to assault that poor defenseless straw man again? And in the same post where you accuse someone else of not understanding what's being said? Where have you seen anyone here declare that NIST's conclusion about column 79 failure "must be true?" What I see being said, over and over, is that you haven't succeeded in proving that it must be false. What I see being said, over and over, is that while there might be a better explanation for the collapse than NIST's "probable cause," you refuse to even attempt to describe a cause that's more probable. Instead, you seem to be hoping that others will fall for logic that you must know is so faulty that you don't dare state it: "missing inch" -> controlled demolition.

The council would benefit from a very careful study of NIST´s report with people like Tony Szamboti, and tof the he missing structural features they have discovered, and of course all the evidence NIST did not mention.

These are very technical issues. I seem to recall that in his initial attempt at calculating the expansion of the floor beam, Tony mistook the published coefficients of thermal expansion as being instantaneous instead of a mean and came up with a number that was too small. Of course, Tony's error does not really bear on the issue, per se, but that error (and others which many here will recall) does call into question your recommendation that anyone should use him as an expert.

You seem to not understand what it will really take to make your case, so instead we get an endless ride on this:

 

[AZCat]

ASTM A572 Grade 50.

Didn't you know?

If I did it was a long time ago and I've switched computers since then so the NIST investigation files are stored somewhere in an archive (I think). Thanks for saving me the trouble of digging through them.

 

[jaydeehess]

K3004 is the longest of the floor beams to the East of the C79-44 girder.
At the opposite end to the one framing into the girder it connects to C38, which in NISTs analysis is taken to be infinitely strong. Given that the girder connection is said to fail due to expansion, is it not reasonable to think that the opposite connection would fail similarly? I know the outside of the building will be cooler, but steel does conduct. This failure at C38 would mean that the beam would push 1" less to the West.
If we are going to allow for column shift to the east this should be quantified and demonstrated possible at least, as has the failure of the C38 connection.

This demonstrates the problem with the 911T approach nicely.
The FEA is an approximation. It necessarily simplifies the structure to make it possible to compute. In that simplification the column between col 79-44 moves significantly, and in the opinion of NIST, sufficiently to consider it having failed and collapsed. Thus the characterization of this as the most probable collapse initiation rather than "this is what happened".

AE911T then mischaracterizes it as "this is what happened" according to NIST and attacks it as such. Fact is that NIST noted strong evidence that col 79 failed (EPH infalling) and then looked for a cause. The only cause which has any evidence to suggest it, is the fires and the fires near col 79 are the most probable to have done this. Quite to the point is the agreement from the CTBUH , an organization that AE911T proponents love to point to as having questioned NIST, which does state that they believe that fire collapsed floors and this led to column failures.

In the above quote, gerrycan now simply assumes a condition that benefits him. Why? Because its one of those simplifications that NIST used and he attacks. William Seeger above notes Ziggi doing the same thing with

What I see being said, over and over, is that you haven't succeeded in proving that it must be false. What I see being said, over and over, is that while there might be a better explanation for the collapse than NIST's "probable cause," you refuse to even attempt to describe a cause that's more probable.

There's a logic fallacy there. Sing along with me, "we're off to see the wizard....."

Attacking the girder failure scenario does not negate the NIST report despite AE911T and its local proponents wishing it to. Plain and simple.

 

[NoahFence]

I wonder how much effort goes into being so ignorant.

 

[jaydeehess]

I wonder how much effort goes into being so ignorant.

Ignorance and a propensity to simple literal thought. My experience is that truthers lack the ability to think in terms other than black and white, yes versus no. Binary thinking. Either NIST is 100% correct or they are 100% wrong. If any detail can be questioned they must be 100% wrong. If they are 100% wrong then all other explanations are better thus CD.