Tony Szamboti
Active Member
How far would column 79 have to move for what you are saying to happen?
Could Girder A2001 Possibly Have got Past the Side Plate on Column 79?
- Thread starter Tony Szamboti
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Tony Szamboti
Active Member
What did the transit have to do with girder A2001 and column 79?
benthamitemetric
Senior Member
Depends how far girder A2001 had already moved.
Oystein
Senior Member
You don't know the distance between the columns. It is NOT what it was before the fires. It changed constantly when the floors (plural!) heated and cooled. Those numbers of yours are meaningless when you don't know what to compare them to.
You implicitly assume a pristine structure away from that one girder. That assumption is heavy nonsense. Why did you ignore my previous post?
Oystein
Senior Member
It proved that exterior colums moved in response to fires. They did not stay in place, as you assume, implicitly. Column 44 may have moved away from column 79, or 79 from 44. You don't know. You assume, implicitly, distance between columns stayed the same all the time.
That's nonsense.
Whitebeard
Senior Member.
Just a laymans question. How do we know that all these columns, girders, links and fixings etc were all in the as installed state after WTC7 had been hit by the falling sections of WTC1? Wouldn't the fact that WTC7 had be clouted by large chucks of falling building cause some damage to structure? Knocked some of the elements out of kilter by a few inches? And my reading of the many pages of debate over several threads on this issue seams to say that a few inches are what is being argued over.
Ill admit, hand on heart I know nothing about architecture and engineering, but to my mind I find it surprising that the damage done to WTC7 by the debris from WTC1 would have no effect at all on the construction elements of WTC7.
Ill admit, hand on heart I know nothing about architecture and engineering, but to my mind I find it surprising that the damage done to WTC7 by the debris from WTC1 would have no effect at all on the construction elements of WTC7.
Tony Szamboti
Active Member
You are trying to say the girder can get by the side plates if its cool, maybe not realizing it would have to be at about room temperature. That can't happen while being pushed by the beams because if the girder cools the beams cool and retract. You seem to want it both ways. That isn't how it would have worked. If the beams are hot, so is the girder, and the girder is almost immediately in the envelope of the side plates if it is hot. Once inside the side plate envelope it doesn't matter how far column 79 is pushed to the east, because the girder cannot get by the side plate and gets pushed to the east with it.
The WTC 1 damage was on the complete opposite corner of WTC 7. It would have had no effect on the northeast corner.
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Tony Szamboti
Active Member
Are you saying "we can never know"?
Tony Szamboti
Active Member
Mick, can you tell us how your sequential heating would allow girder A2001 to ever escape from behind the side plates of column 79 on the 13th floor?
You really need to be more specific.
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Oystein
Senior Member
I am saying what I am saying, Tony: That YOU don't know. Your claims imply an assumption that all the rest of the floor and all other floors are cool and pristine and that colums maintain their as built distances. That assumption is nonsense, I KNOW that it is FALSE.
Hulsey can't know - because he didn't model fire progression, and failed to heat most floors.
You can't know - because you never looked past c79 on floor 13.
But NIST can know! Because they actually modelled all burning floors, and heating and cooling progression through time!
deirdre
Senior Member.
people have repeatedly answered your question.
Please don't spam the thread with your 'argument from incredulity'.
External Quote:
This has also repeatedly been addressed. Repeating false statements over and over will not make them magically become true.
Oystein
Senior Member
I am telling you this in every post here: if the distance between columns 44 and 79 is larger than what you assume, due to many floors heating up and expanding, even an elongated A2001 would have that wiggle room.
deirdre
Senior Member.
Reminder:
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ex:
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Do not post/repeat comments in opposition to that evidence unless you provide evidence to the contrary.
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Tony Szamboti
Active Member
When faced with multiple science based pieces of evidence that there is no chance that girder A2001 could have fallen off its seat at column 79 the reply from those here supporting the notion that it could is nothing more than the unscientific "we can never know" theory or some form of sequential heating could do it with no specifics. Of course, it is transparently clear that would be because they can't defend their position.
Tony Szamboti
Active Member
No, it won't. Girder A2002 is pushing column 79 to the north while A2001 is expanding towards it from the north.
Tony Szamboti
Active Member
I am leaving this forum and I must tell you it is clear you are being tyrannical because you can't support your position in the face of superior evidence which shows it to be false.
Oystein
Senior Member
You are ignoring the fires on all the other floors, the fire history, and the accumulated damage that includes many fail beams and girders. You only look at one connection subjected to one temperature at one point in time. That is not how huge fires destroy buildings!
You assume distances between colums that you have not cannot prove. And I don't mean "we can never", I really mean YOU can't, because you imagine where you should analyse. And HULSEY can't, for he chose not to consider most of the fires, the heat, the damage and the movements in time.
Bust NIST could! Because they did!
No I can't tell you. In fact that's the question under discussion here. But looking at the full 16 floor model I think it's safe to say it's quite complicated, and you really have to take the whole thing into account. To get more specific I'd need to run a simulation of all 16 floors at very high resolution.
I'm not sure "we can never know" is a good explanation, however there are always going to be unknowns. I don't think it's impossible that a heating/expansion/failure pattern could occur that would lead to A2001 missing the side plate. But I also don't think it is impossible that such a pattern might be mathematically proven to be impossible with sufficient computing power.
However I don't think you can prove it with a very local analysis of one heating pattern, as you have done.
Oystein
Senior Member
Your evidence rests on assumptions that you don't try to prove and which are with utmost certainty false. That is not "superior" evidence, that is baseless speculation.
deirdre
Senior Member.
The rule applies to everyone.
Ray Von Geezer
Senior Member.
Another layman here, so sorry if I've missed this amongst all the technical stuff.
If the beam expanded, broke the fixing bolts on its way towards the column, then couldn't it have fallen off as it contracted and cooled? If not, why not?
*Edit* Should have just searched for "cool" within the thread and seen Bentham's posts regarding the reports saying the beam failure was during cooling.
So my question just becomes why are some saying that can't have happened when it appears contraction would take the beam end away from the side plates?
Ray Von
If the beam expanded, broke the fixing bolts on its way towards the column, then couldn't it have fallen off as it contracted and cooled? If not, why not?
*Edit* Should have just searched for "cool" within the thread and seen Bentham's posts regarding the reports saying the beam failure was during cooling.
So my question just becomes why are some saying that can't have happened when it appears contraction would take the beam end away from the side plates?
Ray Von
So looking at the bottom hole, it's 6 3/16" perpendicular from the column face. On 9114"
4 1/4 from the end of the girder. So the largest gap between girder and column is 1 15/16. 1.94", not a lot of leeway on the 1.8 (if that reflects reality).
Some interesting problems with those diagrams though, here's two numbers 1/2 and 3/4
However the 1/2 dimension is bigger than the 3/4 when it should be smaller.
deirdre
Senior Member.
its the girder. not a beam. 2 different things. girders are bigger and have bigger mass than beams, so the distinction matters.
Jeffrey Orling
Senior Member
Not exactly... a girder is ALSO a beam but it supports OTHER beams which are framed into it. Beams may support joists which are technically beams as well.
Girders are obviously larger / stronger than the beams the support.
Oystein
Senior Member
Unfortunately, those who are saying that (contraction pulling girder off) can't have happened either fled the forum or made sure they'd get banned. Us remaining folks could only guess why they say this.
I suppose the remaining folks here agree that no convincing argument is on the table that would force an answer of "No" to the question in the thread title. The consensus being that several hours of travelling fires on multiple floors create a complicated series of responses throughout all parts of the structure, too complex to predict with simple analysis specific details such as distance between any two columns at any one point in time.
The modelling that Hulsey did most likely is far too simple to yield a credible answer, and the even simpler analysis of the likes which Tony Szamboti or gerrycan, our lost members have done, most certainly disregards almost all true premises and are next to worthless.
benthamitemetric
Senior Member
Again, Tony, you are ignoring the complexity of the situation. If the girder initially expanded, it could have pushed column 79 south. And, as has been pointed out to you, we don't know how much of the expansion of the A2001 pushed the north exterior column to the north. We don't know how much column 79 sagged. We don't know how much column 79 bent laterally. We don't know how the failure/buckling of nearby beams caused the loads in the area to be redistributed. We don't know how the failures on other floors affected column 79. We don't know how the uneven heating of A2001 itself affected the way it expanded (your posts treat that girder as if were a uniform temperature). We don't know how the incredible heating in the floor system above and around A2001 affected it as that floor itself shifted in a complex way.
Here are the four scenarios modeled by Arup, which are described in the expert report of Colin Bailey for the Aegis Insurance litigation (which can be found here).
Some notes on limitations: (1) these scenarios were provided in the context of a litigation wherein the plaintiff was claiming that WTC7 failed due to negligence in design/construction, and so they are strictly limited to proving that point (e.g., if Arup had run 500 models and found the girder failed in 1 of them due to negligent design and construction, it would have no obligation to talk about the other 499 here), and (2) like Hulsey, Arup used a more simplistic approach to heating than did NIST and modeled fewer floors than did NIST (though Arup's heating model was at least based on an independent fire progression analysis).
In any case, Arup identified two cases in which A2001 would fail, and neither of them was the exact NIST scenario of being pushed to the west. In fact, both were essentially failures to the north/northeast, with the girder sagging and twisting away from the connection:
Case 1:
Case 3:
Now here's the kicker: The Weidlinger Associates expert report, which was prepared in response to Bailey's expert report, details Weidlinger Associates' review of Arup's files, wherein they found and corrected several key inconsistencies therein:
And there you have it--corrected with consistent connection properties and re-run, the Arup model predicts the failure of girder A2001 in all four scenarios. As in the Arup scenarios, I suspect that 1.8" of side plates were not going to make the difference of whether the building collapsed or not in most fire scenarios. If Tony can prove that they would, then he can make a ton of money consulting on tall building construction/design projects.
If only Hulsey had actually tested the NIST scenario (or if NIST had provided a more detailed narrative or animation), we might have more than best guesses on exactly how the interactions between these elements lead to failure in that exact scenario. In any case, however, taking NIST's and Arup's conclusions together, it seems silly to be so caught up on niggling details that, no matter the model, will still rely on gigantic assumptions about independent variables that are unknowable. Given the huge margin of error in such assumptions, and even inherent in finite element modeling itself, and the huge scale of the structure being modeled, debating about whether 1.8" of movement could or couldn't have happened in a 5-hour long dance of fire and steel is truly missing the forest for the trees. If you tested NIST's exact model, maybe you can convincingly show that they got it wrong for the scenario they suspected. But no one but NIST has even done that to date, and doing that wouldn't even show such movements to be impossible in other scenarios or show other failure-inducing movements to be impossible.
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The note at the bottom of drawing 9114 points out that the sideplates are 1", 2" or 3".
https://www.metabunk.org/attachments/9114jpg-jpg.4104/
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Sure, but that does not mean the diagram is right, it means they drew a 2" thick plate, but dimensioned it as if it were 1"
How could it be right when it is expressing 3 different sized elements in one drawing ?
They could have A) put the line 1/4 of the way though instead of 1/2. or B) used a 1" plate not a 2" plate.
There'll probably be a better drawing out there to illustrate it, floor specific.
Yes, I believe it is
Explained here on page 7 https://www.nist.gov/sites/default/...05/09/WTC7RevisedTechnicalBriefing_111908.pdf
I think we are missing something here. I have notes for this somewhere, and I will look as soon as i can.
ADD I think it is in the column schedule ? , but I don't have it to hand.
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Gamolon
Active Member
I am looking at the individual column drawings and think that a "tier" refers to each column length (majority about 25'-6" column lengths) and what 3 floor elevations they reside within. At this point, I am seeing drawings calling out tier 20 so far. I also see "zones" called out on the drawings (I've seen zones 2, 3, and 4 so far) and maybe "zones" are what is being referred to in the NIST briefing and not "tiers" (being four of them).
For example, drawing 1931 calls out Tier 20, Zone 4 in the title block. The columns is 25'-6" and is within floors 37, 38, and 39.
25'6" would be 2 floors I think (maybe actually a touch less than 2), but yes, that sounds plausible. I am going to look at the column schedule.
I'm presuminging @Christopher 7 picked Drawing 1091 for a reason. But how does 7th, 8th, or 9th tier translate to Floor 13?
Gamolon
Active Member
Agreed.
For example, on drawing 1931, the bottom of the beam is 3'-6" above floor 37. Finished floor/top of concrete for floor 37 is elevation 777'-6". Floor 38 is 12'-9" above that at finished floor/top of concrete elevation 790'-3". Floor 39 is 12'-9" above that at finished floor/top of concrete 803'-0". The top of the column is 3'-6" above elevation 803'-0".
Gamolon
Active Member
On the far left of the drawing, at the bottom of the column, they call out three different finished floor elevations, 11th floor, 13th, floor, and 15th floor. In the middle of the columns that call out 12th floor, 14th floor, and 16th floor. At the top of the column they call out 13th floor, 15th, floor, and 17th floor.
7th tier looks to be the 11th, 12th, and 13th floors. 8th tier looks to be comprised of the 13th, 14th, and 15th floors. The 9th tier looks to be comprised of the 15th, 16th, and 17th floors.
Trying to confirm if this is the case.
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