AE911 Truth's WTC7 Evaluation Computer Modelling Project

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Dr Hulsey stated where the elements ended up in his analysis.
He contrasted that with where the elements ended up in NIST's analysis.
What exactly is your objection again ?

His measurement of where column 79 ended up relative to the center of stiffness (and, by the way, Mick is right to point out above that the center of stiffness should have of course moved as damage accumulated in the building from the fire--so we actually don't know where column 79 ended up in Hulsey's model because he doesn't even tell us how far the center of stiffness moved during his simulation) is not the same thing as NIST's measurement of where the south end of girder A2001 ended up relative to the bearing seat on column 79. Two totally different measurements. They are not comparable. Hence the false comparison. Meanwhile, NIST's stated number is actually useful for evaluating whether girder A2001 failed, while Hulsey's is just a number, the relevance of which you have failed to establish over 3-4 pages of nonsense posts.
 
His measurement of where column 79 ended up relative to the center of stiffness (and, by the way, Mick is right to point out above that the center of stiffness should have of course moved as damage accumulated in the building from the fire--so we actually don't know where column 79 ended up in Hulsey's model because he doesn't even tell us how far the center of stiffness moved during his simulation) is not the same thing as NIST's measurement of where the south end of girder A2001 ended up relative to the bearing seat on column 79. Two totally different measurements. They are not comparable. Hence the false comparison. Meanwhile, NIST's stated number is actually useful for evaluating whether girder A2001 failed, while Hulsey's is just a number, the relevance of which you have failed to establish over 3-4 pages of nonsense posts.
The position was judged relative to the CoS yes.
But listen again to what he said.
He says that it moved to the East. Just because the CoS was his datum point, the statement has exactly the same weight, in fact more weight than NIST's.

The column moved to the East.
 
The position was judged relative to the CoS yes.
But listen again to what he said.
He says that it moved to the East. Just because the CoS was his datum point, the statement has exactly the same weight, in fact more weight than NIST's.

The column moved to the East.

Where did the center of stiffness move in Hulsey's simulation? Do you not know exactly? If you don't know, how do you know where column 79 truly moved in Hulsey's study?

You can give Hulsey's meaningless measurement and false comparison all of the weight you want, but no matter how much importance you try to will into Hulsey's meaningless measurement and false comparison, that measurement (1) will not be the same measurement as provided by the displacement figure stated by NIST, and hence comparing it to NIST's stated displacement figure is a false comparison, and (2) will not tell you if girder A2001 would fail, which goes to why NIST didn't bother stating it.
 
Where did the center of stiffness move in Hulsey's simulation? Do you not know exactly? If you don't know, how do you know where column 79 truly moved in Hulsey's study?

You can give Hulsey's meaningless measurement and false comparison all of the weight you want, but know matter how much importance you try to will into Hulsey's meaningless measurement and false comparison, that measurement (1) will not be the same to the displacement figure stated by NIST, and hence comparing it to NIST stated displacement figure is a false comparison, and (2) will not tell you if girder A2001 would fail, which goes to why NIST didn't bother stating it.
He used the CoS as a datum. If it moved, his datum did not.
the fact remains that Dr Hulsey stated quite clearly that the column moved to the East.
that is actually a more valid statement than NIST's because as has been established by yourself in this thread, NIST did not give a clear position for where the column ended up.

In Dr Hulsey's model. The column moved East. Just because that position was ascertained by using the CoS as a datum point, does not change the statement - It moved to the East. ie to the right as he said as he was giving the presentation.
 
He used the CoS as a datum. If it moved, his datum did not.
the fact remains that Dr Hulsey stated quite clearly that the column moved to the East.
that is actually a more valid statement than NIST's because as has been established by yourself in this thread, NIST did not give a clear position for where the column ended up.

In Dr Hulsey's model. The column moved East. Just because that position was ascertained by using the CoS as a datum point, does not change the statement - It moved to the East. ie to the right as he said as he was giving the presentation.

Center of stiffness is a variable, not a fixed point, as the video you linked earlier made very clear. Can you cite me in the video where Hulsey said the center of stiffness remained fixed? If it did, then his use of the center of stiffness is even more meaningless than we suspected because, to the extent that "datum" tells us anything, it is with respect to the building's actual condition at any point in time.

And no one is contesting that Hulsey's model resulted in the column moving east. You are failing to address the actual criticisms: (1) Hulsey's measurement of the movement of column 79 relative to the center of stiffness is not the measuring the same vector as NIST's measurement of the movement of column 79 relative to the south end of girder A2001, (2) Hulsey's measurement of the movement of column 79 relative to the center of stiffness is less relevant than NIST's stated measurement of the movement of column 79 relative to the south end of girder A2001 because Hulsey's number doesn't tell you whether failure occurs, while NIST's does, and (3) all of Hulsey's movement calculations are in error because he did not model an actual fire progression and did not factor into them structural damage outside of 2 very small areas on two floors (while we know at least 7 floors had fire damage).
 
wp8e3fb649_05_06.jpg You clearly have not thought this through Bentham.
Look again at E12/13 and listen to what Dr Hulsey actually said. He stated that the whole building moved wrt the CoS.
But then he talks about where the column ended up. When he is saying that it moved to the East, he is saying that wrt it's original position, the column moved East.
Where else could it go - Here's the floor plan.
 
wp8e3fb649_05_06.jpg You clearly have not thought this through Bentham.
Look again at E12/13 and listen to what Dr Hulsey actually said. He stated that the whole building moved wrt the CoS.
But then he talks about where the column ended up. When he is saying that it moved to the East, he is saying that wrt it's original position, the column moved East.
Where else could it go - Here's the floor plan.

So you contend that Hulsey didn't dynamically update his calculation of the center of stiffness to take into account the damage to the building? Great. For the sake of argument, let's assume Hulsey got that wrong as you say.

And that leaves us here:

... no one is contesting that Hulsey's model resulted in the column moving east. You are failing to address the actual criticisms: (1) Hulsey's measurement of the movement of column 79 relative to the center of stiffness is not the measuring the same vector as NIST's measurement of the movement of column 79 relative to the south end of girder A2001, (2) Hulsey's measurement of the movement of column 79 relative to the center of stiffness is less relevant than NIST's stated measurement of the movement of column 79 relative to the south end of girder A2001 because Hulsey's number doesn't tell you whether failure occurs, while NIST's does, and (3) all of Hulsey's movement calculations are in error because he did not model an actual fire progression and did not factor into them structural damage outside of 2 very small areas on two floors (while we know at least 7 floors had fire damage).
 
So you contend that Hulsey didn't dynamically update his calculation of the center of stiffness to take into account the damage to the building? Great. For the sake of argument, let's assume Hulsey did something else wrong.

And that leaves us here:

As I understand it, they loaded the model of floor 13 and established where the CoS was, and then used that as their fixed point. You are now trying to criticise him for not updating a figure that NIST didn't even mention.
the fact remains that the column moved East by about 2" in his analysis. his comparison could have been made with more clarity, yes, but the comparison is valid.
Given that the column connections are intact in his model, where else could it move?
 
As I understand it, they loaded the model of floor 13 and established where the CoS was, and then used that as their fixed point. You are now trying to criticise him for not updating a figure that NIST didn't even mention.
the fact remains that the column moved East by about 2" in his analysis. his comparison could have been made with more clarity, yes, but the comparison is valid.
Given that the column connections are intact in his model, where else could it move?

There was no reason to use the center of stiffness at all in this context. But using it as a fixed point? That's even worse than not using it. It's not a fixed point; it is a dependent variable. If he wanted a fixed point, he could have just used the as-built location of column 79. All these silly, nonsensical choices he made seem amateurish.

Meanwhile, the main criticisms of Hulsey's use of the measurement, in any case, remain unaddressed by you or anyone:

... no one is contesting that Hulsey's model resulted in the column moving east. You are failing to address the actual criticisms: (1) Hulsey's measurement of the movement of column 79 relative to the center of stiffness is not the measuring the same vector as NIST's measurement of the movement of column 79 relative to the south end of girder A2001, (2) Hulsey's measurement of the movement of column 79 relative to the center of stiffness is less relevant than NIST's stated measurement of the movement of column 79 relative to the south end of girder A2001 because Hulsey's number doesn't tell you whether failure occurs, while NIST's does, and (3) all of Hulsey's movement calculations are in error because he did not model an actual fire progression and did not factor into them structural damage outside of 2 very small areas on two floors (while we know at least 7 floors had fire damage).
 
There was no reason to use the center of stiffness at all in this context. But using it as a fixed point? That's even worse than not using it. It's not a fixed point; it is a dependent variable. If he wanted a fixed point, he could have just used the as-built location of column 79. All these silly, nonsensical choices he made seem amateurish.

Meanwhile, the main criticisms of Hulsey's use of the measurement, in any case, remain unaddressed by you or anyone:
Okay, I will try asking the question this way.
Do you think that when Dr Hulsey is saying that column 79 is moving to the East, he means that with respect to the column's original position ?
I do.
ADD - I believe that was ascertained from the model in which he established the AS BUILT CoS, but he expressed it wrt the column's original position.
 
Okay, I will try asking the question this way.
Do you think that when Dr Hulsey is saying that column 79 is moving to the East, he means that with respect to the column's original position ?
I do.

I think he meant exactly what he said: that his measurement was of it moving relative to the center of stiffness. If he didn't also recalculate the center of stiffness to reflect the damage to the building, then he clearly made yet another error. But, as I've said, I'm willing to accept that error and write it off as just another amateur mistake. Let's assume, for the sake of argument, that he did mean to say his measurement was the movement of column 79 relative to its original position. The actual main criticisms of Hulsey's measurement await you:

... no one is contesting that Hulsey's model resulted in the column moving east. You are failing to address the actual criticisms: (1) Hulsey's measurement of the movement of column 79 relative to the center of stiffness is not the measuring the same vector as NIST's measurement of the movement of column 79 relative to the south end of girder A2001, (2) Hulsey's measurement of the movement of column 79 relative to the center of stiffness is less relevant than NIST's stated measurement of the movement of column 79 relative to the south end of girder A2001 because Hulsey's number doesn't tell you whether failure occurs, while NIST's does, and (3) all of Hulsey's movement calculations are in error because he did not model an actual fire progression and did not factor into them structural damage outside of 2 very small areas on two floors (while we know at least 7 floors had fire damage).
 
I think he meant exactly what he said: that his measurement was of it moving relative to the center of stiffness. If he didn't also move the center of stiffness to reflect the damage to the building, then he clearly made yet another error. But, as I've said, I'm willing to accept that error and write it off as just another amateur mistake. Let's assume, for the sake of argument, that he did mean to say his measurement was the movement of column 79 relative to its original position. The actual main criticisms of Hulsey's measurement await you:

Okay then, I think we can clear this up then.
If what you think is true, it would need to move in WHICH direction with respect to it's original position ?
 
Okay then, I think we can clear this up then.
If what you think is true, it would need to move in WHICH direction with respect to it's original position ?


Keep the above in mind when you answer that Bentham.
As I said, you haven't thought it through.
 
Okay then, I think we can clear this up then.
If what you think is true, it would need to move in WHICH direction with respect to it's original position ?

This question is horribly vague and not at all responsive to my last post. If you want to make another claim to distract from the fact that you cannot address that post, can you at least state it affirmatively and save us another few pages of nonsense?
 
This question is horribly vague and not at all responsive to my last post. If you want to make another claim to distract from the fact that you cannot address that post, can you at least state it affirmatively and save us another few pages of nonsense?
No it is not vague at all. I am asking you that if the column moved East wrt the CoS, as opposed to East wrt it's original position, then what is the difference?
I say it moves east from it's own position and with respect to it's original position.

It's pinned from EVERY other direction by girders.
 
No it is not vague at all. I am asking you that if the column moved East wrt the CoS, as opposed to East wrt it's original position, then what is the difference?
I say it moves east from it's own position and with respect to it's original position.

It's pinned from EVERY other direction by girders.

If the center of stiffness moved (as necessitated by the fact that it is a dependent variable and the structure around it changed due to damage) while the original position could not move (by definition), then there will necessarily be a difference in the relative measurement as between each such point and a third point (in this case, the location of column 79 after the simulation has run). So, yes, Hulsey using a dependent variable as his "fixed reference point" would be a silly error. But, as I've said, we can accept that error in arguendo and pretend that by "center of stiffness" Hulsey actually meant "the original location of column 79." The main criticisms remain the same, mutatis mutandis, and remain just as unaddressed by you now as 6 posts ago:

... no one is contesting that Hulsey's model resulted in the column moving east. You are failing to address the actual criticisms: (1) Hulsey's measurement of the movement of column 79 relative to the center of stiffness is not the measuring the same vector as NIST's measurement of the movement of column 79 relative to the south end of girder A2001, (2) Hulsey's measurement of the movement of column 79 relative to the center of stiffness is less relevant than NIST's stated measurement of the movement of column 79 relative to the south end of girder A2001 because Hulsey's number doesn't tell you whether failure occurs, while NIST's does, and (3) all of Hulsey's movement calculations are in error because he did not model an actual fire progression and did not factor into them structural damage outside of 2 very small areas on two floors (while we know at least 7 floors had fire damage).
 
If the center of stiffness moved (as necessitated by the fact that it is a dependent variable and the structure around it changed due to damage) while the original position could not move (by definition), then there will necessarily be a difference in the relative measurement as between each such point and a third point (in this case, the location of column 79 after the simulation has run). So, yes, Hulsey using a dependent variable as his "fixed reference point" would be a silly error. But, as I've said, we can accept that error in arguendo and pretend that by "center of stiffness" Hulsey actually meant "the original location of column 79." The main criticisms remain the same, mutatis mutandis, and remain just as unaddressed by you now as 6 posts ago:

Bottom line Bentham, and back to the issue - NIST's model says 6.25 West. Dr Hulsey's says almost 2" East.
The comparison is valid regardless of where and what the fixed point of reference is providing both values are taken wrt the original position of the column.
 
Bottom line Bentham, and back to the issue - NIST's model says 6.25 West. Dr Hulsey's says almost 2" East.
The comparison is valid regardless of where and what the fixed point of reference is providing both values are taken wrt the original position of the column.

Bottom line: they were talking about two different vectors. Your attempt to equate those measurements makes no sense. One is the measurement of the column relative the center of stiffness (or its original position--you choose), while the other is the movement of the column relative to girder A2001. There is no reason to expect those two different measurements to be the same, even in the same model. Comparing them makes no sense. And this is only point one of the three points you cannot address:

... no one is contesting that Hulsey's model resulted in the column moving east. You are failing to address the actual criticisms: (1) Hulsey's measurement of the movement of column 79 relative to the center of stiffness is not the measuring the same vector as NIST's measurement of the movement of column 79 relative to the south end of girder A2001, (2) Hulsey's measurement of the movement of column 79 relative to the center of stiffness is less relevant than NIST's stated measurement of the movement of column 79 relative to the south end of girder A2001 because Hulsey's number doesn't tell you whether failure occurs, while NIST's does, and (3) all of Hulsey's movement calculations are in error because he did not model an actual fire progression and did not factor into them structural damage outside of 2 very small areas on two floors (while we know at least 7 floors had fire damage).
 
bentham - This is the claim from Mick that is in dispute,
"The study makes incorrect displacement comparisons. In both 2016 and 2017 Dr. Hulsey made much of a difference in the displacement at column 79 (5.5" west vs. 2" east). But he appears to be comparing the wrong values — global instead of local displacements"

the fact is that the column movement from Dr Hulsey's mode is wrt it's original position, 2" Eastl
 
bentham - This is the claim from Mick that is in dispute,
"The study makes incorrect displacement comparisons. In both 2016 and 2017 Dr. Hulsey made much of a difference in the displacement at column 79 (5.5" west vs. 2" east). But he appears to be comparing the wrong values — global instead of local displacements"

the fact is that the column movement from Dr Hulsey's mode is wrt it's original position, 2" Eastl

And Mick is right, which is why you cannot address the three points:

... no one is contesting that Hulsey's model resulted in the column moving east. You are failing to address the actual criticisms: (1) Hulsey's measurement of the movement of column 79 relative to the center of stiffness is not the measuring the same vector as NIST's measurement of the movement of column 79 relative to the south end of girder A2001, (2) Hulsey's measurement of the movement of column 79 relative to the center of stiffness is less relevant than NIST's stated measurement of the movement of column 79 relative to the south end of girder A2001 because Hulsey's number doesn't tell you whether failure occurs, while NIST's does, and (3) all of Hulsey's movement calculations are in error because he did not model an actual fire progression and did not factor into them structural damage outside of 2 very small areas on two floors (while we know at least 7 floors had fire damage).

Hulsey's measurement of 2" of movement of column 79 relative to center of stiffness (or its original position--you choose) is what it is. But it's not directly comparable to NIST's value for the measurement of an entirely different vector.
 
The difference here is, that NIST don't specify the movement East by the column as 2", but Dr Hulsey does.
the difference in the analyses is that in Dr Hulsey's the connection does not break, and "everything moves together", and this is due to the composite floor system, and the elements on the drawings being present in Dr Hulsey's, and not in NIST's, such as the shear studs on the girder, that NISt denied the presence of.
 
Yes, this is part of my point. The only reason we are arguing is because @gerrycan insists on repeating Hulsey's mistake in equating the measurements of two different vectors.
I asked you to reference it above, you can't.
When Dr Hulsey says the column moved 2" East, that's what he means. the column moves 2" East.
 
Yes, this is part of my point. The only reason we are arguing is because @gerrycan insists on repeating Hulsey's mistake in equating the measurements of two different vectors.
I think he may just not be expressing his thoughts adequately. remember Hulsey's '[column moving 2" east]' is the same as [the girder moved 2"east] because Hulsey has them welded together with no bolt breakage or anything.

(I apologize to Hulsey if I'm saying this a bit wrong.. just trying to get a point across)
 
Since the connection does not break, as Mick stated the displacement between the local elements that make up the connection is Zero. Therefor the comparison in the presentation is good, because as we have just established - The column moved 2" East.

ADD - My whole point here is that NIST did not specify HOW FAR East the column moved, so there is no way of adding or subtracting that from the girder's travel distance to work out the net movement.
 
Source that please.
What makes you think that Dr hulsey is NOT expressing the movement of the column wrt it's original position ?

The fact that he said he was expressing it as relative to the center of stiffness, as we've now already discussed five times in the last hour.

Meanwhile, the 6.25" inches of displacement by NIST, was not the measurement of the movement of column 79 relative to the center of stiffness (fixed or unfixed) or its original position; it was the measurement of the movement the column seat relative to the south end of girder A2001. No matter how you cut it, it was a different measurement.
 
Since the connection does not break, as Mick stated the displacement between the local elements that make up the connection is Zero. Therefor the comparison in the presentation is good, because as we have just established - The column moved 2" East.

Except even Hulsey shows that the connection DOES break. His contention is that, even though it breaks, the girder doesn't fall off the seat. But if the girder doesn't move relative to column 79 in Hulsey's model, then it cannot even get trapped. It would just sit on the seat as the seat moves.
 
Except even Hulsey shows that the connection DOES break. His contention is that, even though it breaks, the girder doesn't fall off the seat. But if the girder doesn't move relative to column 79 in Hulsey's model, then it cannot even get trapped. It would just sit on the seat as the seat moves.
Does the connection break in the model that Dr Hulsey uses in making the comparison ? Yes/No
 
Do Hulsey's models have divergent outcomes such that they are inconsistent?
Yes. He did several different models. Some of them replicated NIST's conditions and THOSE are the ones you are talking about where the connection broke. So the one that he uses to make the comparison - Did the connection break in that one ? Yes/No

(you know fine well that it did not) because you already accepted the Zero displacement point re the local elements.
 
Yes. He did several different models. Some of them replicated NIST's conditions and THOSE are the ones you are talking about where the connection broke. So the one that he uses to make the comparison - Did the connection break in that one ? Yes/No

(you know fine well that it did not) because you already accepted the Zero displacement point re the local elements.

Why did Hulsey's models come to such different conclusions? I thought there were two models --SAP2000 and Abaqus, each of which modeled the same areas on floors 12 and 13 under the same (unrealistic) heating conditions, no? Which exact model are you talking about and which exact set of conditions?
 
Why did Hulsey's models come to such different conclusions? I thought there were two models --SAP2000 and Abaqus, each of which modeled the same areas on floors 12 and 13 under the same heating conditions, no? Which exact model are you talking about and which exact set of conditions?
No, again you are deliberately trying to muddy the waters here.
Dr Hulsey clearly states in the presentation, for example, that they had to increase the CTE in the steel by 40% to get anything like a failure like NIST's and even then, when the stiffener plates (which NIST left out) are added, there is no failure.
If you are not aware of the content of the presentation, you should go watch it again.

ADD - It is important that I add to that the importance of the column side plate lip preventing the girder from failing to the West, as Tony pointed out earlier today.
 
No, again you are deliberately trying to muddy the waters here.
Dr Hulsey clearly states in the presentation, for example, that they had to increase the CTE in the steel by 40% to get anything like a failure like NIST's and even then, when the stiffener plates (which NIST left out) are added, there is no failure.
If you are not aware of the content of the presentation, you should go watch it again.

Failure does not necessarily occur as the result of girder movement. Girder movement can happen without failure, such as in the trapping scenario you have claimed occurred. So can you please specify exactly where the south end of girder A2001 was relative to column 79 in the model we are discussing wherein column 79 moved 2" east relative to the center of stiffness (or its original position--you choose). Thanks.
 
So can you please specify exactly where the south end of girder A2001 was relative to column 79 in the model we are discussing wherein column 79 moved 2" east relative to the center of stiffness (or its original position--you choose).
0. it moved zero.

it did not move 2" to the east. it did not move at all.
 
Failure does not necessarily occur as the result of girder movement. Girder movement can happen without failure, such as in the trapping scenario you have claimed occurred. So can you please specify exactly where the south end of girder A2001 was relative to column 79 in the model we are discussing wherein column 79 moved 2" east relative to the center of stiffness (or its original position--you choose). Thanks.
In which analysis ?
You need to be clear about that. You just stated that the results were divergent without (apparently) knowing that Dr Hulsey ran different analyses, despite him making that VERY clear in the presentation.
So which of Dr Hulsey's analyses, that you were not aware of 5 minutes ago, are you asking about now ?
 
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