Metatheory and the NIST report

[pomeroo]

Pomeroo:

You see this is the whole point of this thread!

Frank, I do understand that this is the point of the thread. That is why I keep asking you to tell us how much significance you--not the researchers at NIST--attach to the loss of fireproofing in determining the ultimate result.

NIST cannot demonstate how much insulation was lost, where it was lost, and if those areas were also subject to severe heating. NIST makes the assumtion that the loss of insulation is correlated with the damage to the furniture, and NIST is able to model this damage.

Is it possible, then, that damage to furniture could be uncorrelated with loss of insulation? In other words, can we separate the two? We could, for example, set off an explosive in an area where the insulation was unaffected by the impact of the plane. The blast would destroy furniture-- AND it would dislodge a certain amount of fireproofing. All of which would leave us--where?
We would still be looking for residue of the explosive, no? And if we found nothing to suggest the use of an explosive, what should we conclude?

However, we have no way of checking the correctness of the furniture damage model because the degree and location of the furniture damage is also unknown!

Can you really mean what you seem to be saying here? Weren't the tests designed specifically to model a range of possible outcomes?

Thus we have a theory that depends on two assumptions, both of which cannot be verified or negated. What is more, I have shown that there are ways to generate localized heating that are not considered by NIST, and do not depend on the damage to the furniture. So, Pomeroo, how do we know which theory is correct when both predict the same collapse behavior?

Why are you presenting a false dichotomy? Your discovery of an additional heat source need not contradict NIST's explanation: it can modify or amplify it. Only if we posit that little or no fireproofing was dislodged--an extraordinary claim--can we speak of overturning the conclusion reached by NIST.

To return to my boxing metaphor, we began with the statement that the champ knocked out his opponent with a combination. It turned out that there was a big punch that no one noticed. Our revised conclusion is that the champ knocked out his opponent with a combination. Do you see what I'm getting at?

NIST says that the impact of the plane dislodged fireproofing thereby augmenting the effects of the fires. You say that NIST overlooked sources of heat that augmented the effects of the fires. My impression is that you've supplemented the NIST explanation, rather than challenged it.

Nevertheless, Occam's razor says: "TAKE OUT THE FURNITURE!"

Again, what is the significance of the loss of fireproofing? Why should Occam's razor ask us to remove the furniture when it has been established beyond any conceivable doubt that the furniture was present? Surely we are not multiplying entities unnecessarily when the entities in question are not merely being postulated, but were certainly real. What possible reason could we have for assuming--indeed, for wanting to assume--that the furniture was not combustible? Did any of it survive?

 

[R.Mackey]

Why are tests that confirm or discount a theory "unnecessary"? Why are they not very necessary in this, of all cases? Hell, even if it cost $100M to perform these tests, wouldn't you want to see the results? Especially if they demonstrated the official theory to be right?

They are unnecessary because it's just not that complicated. Look, I've taken solid mechanics. I know the strength of steel as a function of temperature. I know how to set up an FEA of a truss structure. I know how to validate that FEA. Why on earth would I need to run a specific test? If I did, what would be the value of my model?

Let me say this one more time, and only one more time: The purpose of the full-scale fire tests in NCSTAR1-6B was to test the fire rating of an as-built assembly. That's it. It was not done to support the structural fire response model, nor was it needed. The fact that it verifies unit tests of the structural fire response model is an added bonus, but secondary to the purpose of the test.

ETA: I may have confused 1-6B and 1-6C in previous writings... 1-6B is the full-scale tests. 1-6C is the component simulations. Sorry if I screwed that up. It's hard to keep the whole NIST report in memory.

Yet, NIST cites the failure of these trusses as "imminent." As if that word were some kind of satisfactory criteria of the truth of their theory. What criteria is "immanent" calibrated against? Does it mean it will fail in 5 minutes under the identical conditions? 40 minutes? We do not know because they do not define "imminent". Again, we must take their word for the results in the report.

Argumentative. Take a look at the longer narratives in 1-6B. The structures were judged to be in "imminent failure" on the basis of spalling, creaking, mid-element deformation appearing in the diagonals, and reaching maximum mid-span elastic deflection. Experts running the tests made the call. You are speculating without data or training that they may have been incorrect.

So, yes, you must take their word. You have no credible alternative.

Except in the NIST lab tests, the trusses did not fail, and in the simulations, they did fail. The only meaningful difference imaginable. There are some definite problems with the interpretation of the data here.

Apples to oranges comparison. I've already explained this.

But when we examine the actual model they used to demonstrate the failure of the truss systems, we see that it is dependent on heating the entire structure to 700C--a premise for which there is absolutely no corroborative evidence.

“A floor section was modeled to investigate failure modes and sequences of failures under combined gravity and thermal loads. The floor section was heated to 700 °C (300 °C at the top surface of the slab) over a period of 30 min…. Figure 6–11 shows that the diagonals at the core (right) end of the truss buckled and caused an increase in the floor system deflection, ultimately reaching approximately 42 in.”(96)

This is a different apples to oranges comparison. What you are describing above is the unit test, not the actual structural failure model. This unit test uses unrealistic and simple boundary conditions to make it directly comparable to a directly solvable or furnace-test result.

NIST absolutely does not suggest that the temperature profile above is what happened in the Towers. That information comes from NCSTAR1-5F. It shows nothing at all like a constant profile, not in time or in space.

Not only is there no corroborative evidence of this, but in another statement, they clarify that

“The use of an ‘average’ gas temperature was not a satisfactory means of assessing the thermal environment on floors this large and would also have led to large errors in the subsequent thermal and structural analyses. The heat transferred to the structural components was largely by means of thermal radiation, whose intensity is proportional to the fourth power of the gas temperature. At any given location, the duration of temperatures near 1,000 °C was about 15 min to 20 min. The rest of the time, the calculated temperatures were near 500 °C or below.”(127)

So, given 1000C for 20 minutes, there is no way the floor systems could have entirely heated to 700C for 30 minutes, yet they combine these data as if there were no contradiction between them, in order to produce the lynch pin of their position: that the floor trusses sagged from the heat and initiated the "global collapse."

Does this sound like a consistent integration of data?

NIST did not integrate data in the way you describe.

The heating of steel is a function of its fireproofing as well. The fire models give us temperature, that plus fireproofing estimate gives us rate of heating, that plus steel element size gives us rate of temperature rise, integrated over time gives us steel temperature as a function of time.

As before, the "entirely heated to 700 C for 30 minutes" is not and never was intended to represent actual conditions in the Towers. It's a test case. This provides our verification of the models before we do the real calculation. You've strung together several totally unrelated experiments, so it should be no surprise that it leads to no sensible conclusion.

Sure, that sounds fair. But if anyone asks me to take their results as truth, but is unable to produce a test to back them up because "it would be too costly or difficult," then they are, in fact, asking me to take some results as gospel.

It's certainly possible that I may be at fault for misunderstanding the data. Stranger things have happened, but so far, it is the structure of the NIST argument to which I take objection. (And that is my background.)

I still think the confusion is strictly on your side. Your objections thus far constitute a "cherry picking" approach, and do not follow the logical flow of the NIST investigation.

I would suggest you re-read NCSTAR1-5 before proceeding. That should clear up all of the mistakes you've made here.

 

[Crazy Chainsaw]

Frank, I do understand that this is the point of the thread. That is why I keep asking you to tell us how much significance you--not the researchers at NIST--attach to the loss of fireproofing in determining the ultimate result.







Is it possible, then, that damage to furniture could be uncorrelated with loss of insulation? In other words, can we separate the two? We could, for example, set off an explosive in an area where the insulation was unaffected by the impact of the plane. The blast would destroy furniture-- AND it would dislodge a certain amount of fireproofing. All of which would leave us--where?
We would still be looking for residue of the explosive, no? And if we found nothing to suggest the use of an explosive, what should we conclude?







Can you really mean what you seem to be saying here? Weren't the tests designed specifically to model a range of possible outcomes?





Why are you presenting a false dichotomy? Your discovery of an additional heat source need not contradict NIST's explanation: it can modify or amplify it. Only if we posit that little or no fireproofing was dislodged--an extraordinary claim--can we speak of overturning the conclusion reached by NIST.

To return to my boxing metaphor, we began with the statement that the champ knocked out his opponent with a combination. It turned out that there was a big punch that no one noticed. Our revised conclusion is that the champ knocked out his opponent with a combination. Do you see what I'm getting at?

NIST says that the impact of the plane dislodged fireproofing thereby augmenting the effects of the fires. You say that NIST overlooked sources of heat that augmented the effects of the fires. My impression is that you've supplemented the NIST explanation, rather than challenged it.





Again, what is the significance of the loss of fireproofing? Why should Occam's razor ask us to remove the furniture when it has been established beyond any conceivable doubt that the furniture was present? Surely we are not multiplying entities unnecessarily when the entities in question are not merely being postulated, but were certainly real. What possible reason could we have for assuming--indeed, for wanting to assume--that the furniture was not combustible? Did any of it survive?

The fire proofing dislodgement was first proposed by the Society of engineers the only scenario that worked in to cause collapse was the worst case scenario That is what NIST adopted.

Frank's reaction which I have also recreated to some degree in experiments would cause the trusses to bow and weaken the structure if the damage was minimal, or the insulation not degraded at all.

The fire proofing may in fact have been damaged worse than NIST estimates or not Damaged at all it is simply an unknown.
All we know is that NIST found no evidence of perimeter column temperatures over 250c where there was paint to test. That indicates highly localized heating.
The Floor pans are gone and not accounted for and the trusses and steel in some of the buildings are Chlorinated and Sulfated, and we have some unusual metal spheres that are directly related to high temperature reactions.
Hot aluminum oxide tend not to bounce off of steel, it embeds, hot aluminum oxide would have penetrated the steel floor pans as if they were tissue paper, that penetration, catalyzes Franks reaction in the early fire, by increasing the surface area for reactions to take place.


If someone can correct me on any mistakes I have made please do, information correct and accurate information is always welcome.

PS. I also found a place to produce more spheres, Computers thin metals in them can be ignited and produce spheres at really low temperatures, about 450c.

I am also looking at other sources.

 

[R.Mackey]

The fire proofing dislodgement was first proposed by the Society of engineers the only scenario that worked in to cause collapse was the worst case scenario That is what NIST adopted.

Frank's reaction which I have also recreated to some degree in experiments would cause the trusses to bow and weaken the structure if the damage was minimal, or the insulation not degraded at all.

There's a problem with that theory, though. Dr. Greening's reaction basically adds much more heat to the system, albeit in highly localized areas. But while local, you would require a lot more heat, and that would greatly increase the average heat inside the structure.

The NIST fire models can be partially verified against observation of and through the windows. The first appearance of fire at any location marks the ignition temperature contour as a function of time. Window breakage corresponds to a higher temperature contour. If there is a lot more heat input -- which would be required to defeat undamaged fireproofing -- these observations would be way off.

The fire proofing may in fact have been damaged worse than NIST estimates or not Damaged at all it is simply an unknown.

It is uncertain, but we have photographs of some damaged fireproofing, not to mention evidence from the pieces that were knocked free. I suspect (but cannot prove) that NIST underestimated the fireproofing damage.

All we know is that NIST found no evidence of perimeter column temperatures over 250c where there was paint to test. That indicates highly localized heating.

Nope. I suspect local heating as well, but you can't use the perimeter to prove or refute that. As for the recovered core steel, we don't have enough from the fire floors to make any call about locality either.

The Floor pans are gone and not accounted for and the trusses and steel in some of the buildings are Chlorinated and Sulfated, and we have some unusual metal spheres that are directly related to high temperature reactions.
Hot aluminum oxide tend not to bounce off of steel, it embeds, hot aluminum oxide would have penetrated the steel floor pans as if they were tissue paper, that penetration, catalyzes Franks reaction in the early fire, by increasing the surface area for reactions to take place.

This is all fair. I wouldn't be surprised if these reactions had a slight to moderate effect on the heat budget. I merely dispute that it was such a huge increase that it could have eaten through intact fireproofing.

PS. I also found a place to produce more spheres, Computers thin metals in them can be ignited and produce spheres at really low temperatures, about 450c.

I am also looking at other sources.

The WPI sulfidized steel results also demonstrated that the steel, despite never exceeding 850^oC, experienced some decarburation. It's not much of a stretch to suppose that spherule production was another result, and if so, it's entirely probable for significant quantities of iron spherules to appear at perfectly ordinary temperatures. This is consistent with what you've found here.

 

[David Wong]

Regarding evidence of explosives in the towers:

What if it does exist, and it came from an unbiased and verifiable source? Would you change your theory to account for the evidence or would you dismiss the existence of the evidence anyway?

Of course it would change the theory; discovery of such physical evidence would be earth-shattering in terms of what we thought about the attack. There would be all sorts of questions as to how Al Qaeda got such access to the building, how they were able to get the bombs in and how they were able to plant the bombs undiscovered by security and bomb-sniffing dogs.

Obviously if they were able to do it once, they could do it again, and we would need to take a long, hard look at security procedures. Were the charges somehow undetectable by the dogs? How were the disguised so they went unnoticed by security and maintenance staff? How were they built so that they were able to withstand the impact of the planes? How were they able to operate without the presence of det cord or detonators that could later be discovered by cleanup crews?

It would open up a whole new realm of investigation and would blow the lid of what we know of Al Qaeda's capabilities.

 

[T.A.M.]

Regarding evidence of explosives in the towers:



Of course it would change the theory; discovery of such physical evidence would be earth-shattering in terms of what we thought about the attack. There would be all sorts of questions as to how Al Qaeda got such access to the building, how they were able to get the bombs in and how they were able to plant the bombs undiscovered by security and bomb-sniffing dogs.

Obviously if they were able to do it once, they could do it again, and we would need to take a long, hard look at security procedures. Were the charges somehow undetectable by the dogs? How were the disguised so they went unnoticed by security and maintenance staff? How were they built so that they were able to withstand the impact of the planes? How were they able to operate without the presence of det cord or detonators that could later be discovered by cleanup crews?

It would open up a whole new realm of investigation and would blow the lid of what we know of Al Qaeda's capabilities.

Nice try, but you lost them at...

"There would be all sorts of questions as to how Al Qaeda got such access to the building"

TAM

 

[David Wong]

They bombed the towers once before. It's not out of the question that they'd double-up the 9/11 attack with explosives, a back-up measure to be sure the towers came down and caused maximum casualties. If, during cleanup, workers had come out of the rubble with charred detonators and frayed det cord, we would have shaken our heads and wondered how we were so vulnerable.

I'm not familiar with any record of such evidence but perhaps Jay has knowledge I do not. If so, I hope he shares it. It'll be the biggest piece of 9/11 news to come out in years.

 

[Crazy Chainsaw]

There's a problem with that theory, though. Dr. Greening's reaction basically adds much more heat to the system, albeit in highly localized areas. But while local, you would require a lot more heat, and that would greatly increase the average heat inside the structure.

The NIST fire models can be partially verified against observation of and through the windows. The first appearance of fire at any location marks the ignition temperature contour as a function of time. Window breakage corresponds to a higher temperature contour. If there is a lot more heat input -- which would be required to defeat undamaged fireproofing -- these observations would be way off.

NO because of two factors one Carbon black is a perfect black body radiation source it absorbs light energy, and re-radiates it at a lower frequency, and since the reaction occurs localized, under a slab of high Gypsum concrete
on unfire proofed floor pans, much of the energy would be absorbed by the excellent heat sink provided by the concrete or conducted though the pans.
The concrete would actually be degassing H20 so a high temperature reaction localized on the floor pans and trusses may go un noticed in the videos.
With out evidence in the video NIST could not determine with out accurate experimentation that the reactions took place.
In Fact in the first experiments all I noticed was the steel I used was gone, to took a while for me to figure out to let the reaction take place for a while and then blow the smoke away with compressed nitrogen gas to see the reactions. Fortunately the Oil well people left two cylinders of Nitrogen gas used for testing oil wells, on my property when they went bankrupt.


It is uncertain, but we have photographs of some damaged fireproofing, not to mention evidence from the pieces that were knocked free. I suspect (but cannot prove) that NIST underestimated the fireproofing damage.

There is no way to prove it, unless you know the contents of the buildings, that is the problem to many unknowns.

Nope. I suspect local heating as well, but you can't use the perimeter to prove or refute that. As for the recovered core steel, we don't have enough from the fire floors to make any call about locality either.
The perimeter only proves that the perimeter where paint was left never got hotter than 250c, that could be do to the fact that the fireproofing on the perimeter was less damaged than that on the core.

This is all fair. I wouldn't be surprised if these reactions had a slight to moderate effect on the heat budget. I merely dispute that it was such a huge increase that it could have eaten through intact fireproofing.

The temperature would have far exceeded the max temps of the fire proofing given time, even mineral wool fire proofing has its limits. There was almost nothing left of the floor pans.
I agree with you however that the fire proofing was damaged Probably very severely.

The WPI sulfidized steel results also demonstrated that the steel, despite never exceeding 850^oC, experienced some decarburation. It's not much of a stretch to suppose that spherule production was another result, and if so, it's entirely probable for significant quantities of iron spherules to appear at perfectly ordinary temperatures. This is consistent with what you've found here.

Yes it is, but the problem is some of the spheres can not form at such low temperatures. The ones from blood for instance can form in aluminum oxidation reactions or steel oxidation reactions by simply heating the Blood dropplets to above 1400c driving off the Sodium Chloride.
Dear, R.Mackey energy is the key here, because energy can not only cause extra heating but also some energy forms can cause increased surface area, and lower combustion temperatures of metals Normally hydrogen ebrittlement only occurs at 900c I got it to work at less than 700c by using non Thermal energy on the metal to increase stored energy- fractures and cracks do to wave energy and mechanical stress both at the same time.
I got a Super hot H20 reaction to bounce back and forth on the metals surface-underside causing an intense reaction, I am still working on this, it is incredibly complex and I must admit It may be beyound me to understand all that I have done.
I respect and apreciate your insite and advice R Macky your knowledge in this subject is valued, probibly more than you know. It has helped greatly in my understanding of the events I have witnessed.

 

[jay howard]

They are unnecessary because it's just not that complicated. Look, I've taken solid mechanics. I know the strength of steel as a function of temperature. I know how to set up an FEA of a truss structure. I know how to validate that FEA. Why on earth would I need to run a specific test? If I did, what would be the value of my model?

So, if we are conducting a scientific inquiry into the cause of the collapse of the buildings, we have a few pieces of evidence and some inferences we can make based on observables and calculated parameters of the impacts.

Our forensic evidence tells us: “None of the recovered steel samples showed evidence of exposure to temperatures above 600ºC for as long as 15 min. This was based on NIST annealing studies that established the set of time and temperature conditions necessary to alter the steel microstructure.”(176)

Yet, the simulations required the steel to reach hotter temperatures for longer periods of time in order to fail. We certainly can assume some amount of fire proofing removal from the impact greater than zero--how much, it is impossible to ascertain. You suspect they underestimated it. I suspect otherwise. Our suspicions are irrelevant.

What we can see is that the leap between simulated collapse and the evidence for conditions of the steel in the towers immediately prior to collapse do not match up by several hundred degrees for at least 10 minutes. This leaves a lot of room for speculation as to why NIST altered their simulation input as they did.

It is unreasonable to ask a skeptic (as the Amazing Randi will surely agree) to accept the claims of an interlocutor without corresponding, public reasons that follow some logical sequence. NIST may provide public "reasons," however, I have yet to see the logical sequence by which they substantiate using the "most severe" case for the collapse of both towers. The best "logic" to their argument is that the severe case is the only case in which the towers collapse was "imminent" within the time parameters. The implicit structure of this argument goes from conclusion to substantiation (via computer simulation), NOT from working hypothesis to corroborative tests to final theory--as any rigorous scientific inquiry must.

To simply say "re-read the report" is like a twoofer asking you to simply "watch the collapse again" for confirmation of their view. It's only there if you already believe their conclusion.

Let me say this one more time, and only one more time: The purpose of the full-scale fire tests in NCSTAR1-6B was to test the fire rating of an as-built assembly. That's it. It was not done to support the structural fire response model, nor was it needed. The fact that it verifies unit tests of the structural fire response model is an added bonus, but secondary to the purpose of the test.

The stated purpose of the tests is also irrelevant. They could've said they were testing for floor elves. It wouldn't change the parameters or the results. Now, do these parameters fit the information we have regarding the conditions in the towers prior to the collapse?

Given that none of the recovered steel exhibited temperatures higher than 600C, yes, they do--in fact, they exceeded temperatures of the physical evidence. Given that none of the floor truss systems in the controlled tests failed in the time parameters (by a long-shot), we should draw the conclusion that something is amiss with our theory.

If the floor truss systems had failed in the lab tests, NIST would have crowned them as the KEY finding that corroborated their theory. As they did not fail, NIST moved on to the simulations as their only means of substantiating their position.

ETA: I may have confused 1-6B and 1-6C in previous writings... 1-6B is the full-scale tests. 1-6C is the component simulations. Sorry if I screwed that up. It's hard to keep the whole NIST report in memory.

No prob. No miscommunication here.

Argumentative. Take a look at the longer narratives in 1-6B. The structures were judged to be in "imminent failure" on the basis of spalling, creaking, mid-element deformation appearing in the diagonals, and reaching maximum mid-span elastic deflection. Experts running the tests made the call. You are speculating without data or training that they may have been incorrect.

So, yes, you must take their word. You have no credible alternative.

My point here is that instead of saying "failure was imminent," they could just as truthfully declared, "the trusses withstood the maximum test stresses." Both statements might be true, but which is more representative of the facts? If we have to argue over it, then perhaps the design of the test is ambiguous.

...NIST did not integrate data in the way you describe....As before, the "entirely heated to 700 C for 30 minutes" is not and never was intended to represent actual conditions in the Towers. It's a test case. This provides our verification of the models before we do the real calculation. You've strung together several totally unrelated experiments, so it should be no surprise that it leads to no sensible conclusion.

Then why do they make reference to sagging floor trusses if the only way to make them fail in an appropriate way is to heat the entire piece to 700C for 30 minutes? What possible purpose could that simulation serve if not as an attempt to corroborate their theory?

I still think the confusion is strictly on your side. Your objections thus far constitute a "cherry picking" approach, and do not follow the logical flow of the NIST investigation.

I would suggest you re-read NCSTAR1-5 before proceeding. That should clear up all of the mistakes you've made here.

Maybe you could show me how it is you've managed to make sense of the NIST case by integrating their test data with their simulation data to their conclusion without "cherry picking".

It shouldn't be this hard to make their theory make sense with their own data.

 

[jay howard]

The WPI sulfidized steel results also demonstrated that the steel, despite never exceeding 850^oC, experienced some decarburation. It's not much of a stretch to suppose that spherule production was another result, and if so, it's entirely probable for significant quantities of iron spherules to appear at perfectly ordinary temperatures. This is consistent with what you've found here.

Now where did you get 850C? NIST certainly does not accept that steel got that hot, nor does it ever mention the word "eutectic" nor does it make any reference whatsoever to the WTC steel examined by the Worchester Polytechnic Institute.

In fact, NIST makes no allowance at all, at all for molten steel under any conditions--even though we have undeniable, public confirmation of such. Not only is the WPI steel evidence of molten steel, but, more strangely, it is evidence of an uncommon "eutectic" reaction whose likelihood of happening willy-nilly is less parsimonious than an artificial reaction.

And while we're on it, the existence of ferrous microspheres must also be taken into account since the existence of such has been corroborated by the USGS.

This may turn out to be fodder for another thread, but the point remains that NIST scientists are either not capable or unwilling to even consider these pieces of evidence.

To label them "outside the scope of the NIST report" is to admit failure of the NIST project. This is irrefutable evidence of molten steel, not just aluminum. To say "molten steel bears no relevance to the possible collapse sequence of a steel and concrete structure" is to talk nonsense.

Continue here or another thread?

 

[jay howard]

Regarding evidence of explosives in the towers:



Of course it would change the theory; discovery of such physical evidence would be earth-shattering in terms of what we thought about the attack. There would be all sorts of questions as to how Al Qaeda got such access to the building, how they were able to get the bombs in and how they were able to plant the bombs undiscovered by security and bomb-sniffing dogs.

Obviously if they were able to do it once, they could do it again, and we would need to take a long, hard look at security procedures. Were the charges somehow undetectable by the dogs? How were the disguised so they went unnoticed by security and maintenance staff? How were they built so that they were able to withstand the impact of the planes? How were they able to operate without the presence of det cord or detonators that could later be discovered by cleanup crews?

It would open up a whole new realm of investigation and would blow the lid of what we know of Al Qaeda's capabilities.

This is an issue of parsimony. Once we have established that we cannot simply ignore the evidence of molten steel, we must account for it.

The metatheoretic criteria established in the OP take no account of the political ramifications of theories--only that they must make "sense". Does it make more sense to presume that al qaeda wired the building for destruction or that individuals with expertise in military demolitions got involved, or both, or some other hypothesis?

You will find no predetermined conclusions from me about this matter. This is not a rhetorical question.

Nor does it suffice to dismiss the evidence of molten steel because the logistical problems inherent in any CD theory. I fully admit that any CD theory is difficult to apprehend mostly because of the logistical elements. But if you would like to discount this theory on the basis that "it's just not possible that our own people would murder us to make a point", then it may be you, David, that needs to do some reading about the history of war.

Again, you will not find a predetermined conclusion in any of my writings. I suggest without any sarcasm that we approach all theories with an open mind and with objective criteria of a good theory so that we may come to the conclusion that best fits all the data.

"Once you remove the impossible, whatever remains, however improbable, must be the truth." Doyle

 

[GlennB]

...
In fact, NIST makes no allowance at all, at all for molten steel under any conditions--even though we have undeniable, public confirmation of such. Not only is the WPI steel evidence of molten steel, but, more strangely, it is evidence of an uncommon "eutectic" reaction whose likelihood of happening willy-nilly is less parsimonious than an artificial reaction.
...

So ... it begins

 

[twinstead]

I sense another layman's smackdown of all those 'idiots' at NIST coming on...

 

[David Wong]

This is an issue of parsimony. Once we have established that we cannot simply ignore the evidence of molten steel, we must account for it.

Then indeed you have access to data I do not. I was unaware of:

1. Any evidence of molten steel (I've heard second-hand reports of molten metal, but not necessarily steel);

2. The fact that molten steel is indicative of a controlled demolition. I was aware of molten metal in intense structure fires, but had never heard of it as a side effect of the demolition process.

If you can share the evidence for these two conclusions, we can indeed move on to what the implications are.

 

[GregoryUrich]

Well Gregory I said I wouldn't accuse you of being deliberately obtuse but I cannot understand how an engineer would not recognize the problem with these two statements:

You are implying two things by using this logic, first is that the relationship between momentum and velocity is linear with respect to the overall momentum and individual velocity of debris. This is clearly false as demonstrated by the eventual debris layout.

The second thing you are implying is that NISTs FEA simulation of impact is somehow flawed. The fireproofing loss used in the reports was determined only to occur when office workstations directly below were damaged. Given that the energies required are in the same order of magnitude, am I to assume you question the accuracy of NISTs FEA?

I have explained that I am talking about an average velocity and that there is some distibution of velocities in the debris (for which I proposed a range similar to that given by NIST). Nonetheless, the total momentum and average velocity are linearly proportional.

It is interesting to note that for WTC1, one engine remained in the core and the second engine was determined to have a velocity of 50 mph when it was 1/3 of distance the from the core to the south exterior wall. These are the absolute heaviest and most dense debris components.

I don't have enough information on which to judge the FEA simulation and I don't know if I would understand anyway. Nonetheless, I have seen no indication that NIST modelled the core contents other than partitions. The core also had elevator tracks and cables, air ducts, ac pipes, water pipes, steam pipes, sewer pipes, stairs, service rooms, storage rooms, power lines, and etc. In fact the average partition load was around 20 psf while the average SDL was around 40 psf. So the model may have left out 50% of the mass within the core which debris may have come in contact with.

Regardless of what Mackey says about chaotic systems that are impossible to model, gravity is always strictly inforced. Also, every time something is deflected it loses momentum. I challenge anyone to come up with a realistic scenario by which a debris component actually hits a floor truss on the south side of the building while retaining enough momentum to damage the foreproofing. Consider any initial trajectory and then imagine things bouncing around. Keep in mind that the floor beams in the core were probably at least 24" deep and the truss system 30" deep.

If anyone can find such a scenario, then try to come up with the probability that a significant portion of the debris will follow this trajectory.

 

[T.A.M.]

So Jay, are you still an unemployed caterer? Must be the new way to become an expert on structural engineering.

http://www.goodharborreport.com/Blinded-by-hindsight

TAM

 

[R.Mackey]

So, if we are conducting a scientific inquiry into the cause of the collapse of the buildings, we have a few pieces of evidence and some inferences we can make based on observables and calculated parameters of the impacts.

Our forensic evidence tells us: “None of the recovered steel samples showed evidence of exposure to temperatures above 600ºC for as long as 15 min. This was based on NIST annealing studies that established the set of time and temperature conditions necessary to alter the steel microstructure.”(176)

Yet, the simulations required the steel to reach hotter temperatures for longer periods of time in order to fail.

This is totally false.

If you look at NCSTAR1-3B, you can find the original location of each recovered piece of steel. Then go look at 1-5F, the fire temperature models, and 1-5G, the structural coupling to heat.

You will discover that NIST does not require or even predict that these pieces reached higher temperatures. The observation about the recovered steel is totally consistent with the NIST models and the NIST hypothesis.

We certainly can assume some amount of fire proofing removal from the impact greater than zero--how much, it is impossible to ascertain. You suspect they underestimated it. I suspect otherwise. Our suspicions are irrelevant.

Except that NIST's answer is based on the impact model, the expected strength of the fireproofing, and kinetic energy reasoning on the debris field. Yours is merely argumentative speculation. Yours is not useful or valid.

What we can see is that the leap between simulated collapse and the evidence for conditions of the steel in the towers immediately prior to collapse do not match up by several hundred degrees for at least 10 minutes. This leaves a lot of room for speculation as to why NIST altered their simulation input as they did.

Nonsense. There is no leap, and there is no altering of simulation inputs as you suggest. You pulled this out of thin air.

It is unreasonable to ask a skeptic (as the Amazing Randi will surely agree) to accept the claims of an interlocutor without corresponding, public reasons that follow some logical sequence. NIST may provide public "reasons," however, I have yet to see the logical sequence by which they substantiate using the "most severe" case for the collapse of both towers.

It's spelled out in plain text in the NIST report. The reasoning to select the "most severe" impact is in 1-2B, and the reasoning for the hotter fire case is in 1-5F. The only reason you "have yet to see" it is because you didn't look.

The best "logic" to their argument is that the severe case is the only case in which the towers collapse was "imminent" within the time parameters. The implicit structure of this argument goes from conclusion to substantiation (via computer simulation), NOT from working hypothesis to corroborative tests to final theory--as any rigorous scientific inquiry must.

This is also nonsense. The reasons to select the severe case have little to do with the collapse. Also, the severe case is not the only case that results in a collapse, according to NIST's models.

To simply say "re-read the report" is like a twoofer asking you to simply "watch the collapse again" for confirmation of their view. It's only there if you already believe their conclusion.

Not at all. I'm not asking you to read it to see if it convinces you a second time. I'm asking you to read it because it appears you have no idea what the report actually contains. You've consistently misrepresented NIST's reasoning, logical progression, and decision process.

The stated purpose of the tests is also irrelevant. They could've said they were testing for floor elves. It wouldn't change the parameters or the results. Now, do these parameters fit the information we have regarding the conditions in the towers prior to the collapse?

Argumentative and nonsensical. The stated purpose of the tests reveals that the test parameters had absolutely nothing to do with the conditions in the tower prior to collapse. You simply don't know what you're talking about.

Given that none of the recovered steel exhibited temperatures higher than 600C, yes, they do--in fact, they exceeded temperatures of the physical evidence. Given that none of the floor truss systems in the controlled tests failed in the time parameters (by a long-shot), we should draw the conclusion that something is amiss with our theory.

As I explained above, the recovered steel is consistent with the model.

By the way, all four controlled tests failed in one way or another. Two were halted out of fears of collapse, and the other two halted upon exceeding the maximum measurement range of mid-span deflection. One of the four tests failed to meet its planned fire rating, although this wasn't a big surprise to the investigators.

If the floor truss systems had failed in the lab tests, NIST would have crowned them as the KEY finding that corroborated their theory. As they did not fail, NIST moved on to the simulations as their only means of substantiating their position.

Complete nonsense. If the floor truss systems, fireproofed and intact, had failed in the controlled tests, it wouldn't have corroborated their theory at all. This result would suggest the "Pancake Theory" was the correct one.

Your suggestion that NIST ran these tests, then changed to simulations in order to get the result that they wanted, is totally wrong and disrespectful.

My point here is that instead of saying "failure was imminent," they could just as truthfully declared, "the trusses withstood the maximum test stresses." Both statements might be true, but which is more representative of the facts? If we have to argue over it, then perhaps the design of the test is ambiguous.

We don't have to argue over it. The structural experts running the test said that failure was imminent. Nobody with any qualifications or valid data has said otherwise. There is no argument.

Then why do they make reference to sagging floor trusses if the only way to make them fail in an appropriate way is to heat the entire piece to 700C for 30 minutes? What possible purpose could that simulation serve if not as an attempt to corroborate their theory?

What makes you think that's the only way to make a floor truss fail? It isn't.

The purpose of this simulation, as I am now explaining for the third time, is to provide a unit test of their overall simulation. Before you run the big model, you test it out first with simple boundary conditions and simple model grids -- something easy enough that you already know the answer. That's what the floor test in 1-6C section 5.4.9 is showing, not a test of the actual collapse model.

Maybe you could show me how it is you've managed to make sense of the NIST case by integrating their test data with their simulation data to their conclusion without "cherry picking".

It shouldn't be this hard to make their theory make sense with their own data.

It isn't. All you have to do is read it. I strongly suggest you read at least NCSTAR1 -- it's only about 250 pages -- and see if that doesn't answer your questions.

At this point, it might be a good idea for you to tell us where you're getting your information from. So far, you haven't raised a single scientific criticism. Instead, every one of your complaints has to do with a conclusion that NIST never drew, on the basis of your connecting different parts of the report that have no relation to each other. I've also seen you quote, in this post and the last, what appear to be someone else's footnotes, notes that do not correspond to page numbers in any NIST subreport. If, as it appears, you haven't actually read the report but are instead merely echoing someone else's faulty analysis, then it's no surprise that you're having such problems.

Now where did you get 850C? NIST certainly does not accept that steel got that hot, nor does it ever mention the word "eutectic" nor does it make any reference whatsoever to the WTC steel examined by the Worchester Polytechnic Institute.

I got it from the report that I linked. Here, I'll make it real, real easy for you:

The as-fabricated microstructure consisted of a hot worked banded structure of ferrite and pearlite. In severely "eroded" regions where the thickness had been reduced to less than a 1/16 of and inch significant decarburation was observed. In addition, some pearlite bands presented regions that had re-austentized as well as regions where the pearlite had started to spheroidize. These observations indicate that steel had experienced temperature between 550 and 850^oC.

An examination of the "slag" that formed on the surface of the steel found iron oxides and iron sulfides. It appeared that the "slag" was liquid at high temperature and easily attacked the grain boundaries. A eutectic microstructure was seen within the "slag" of iron oxides and iron sulfides. If these compounds were pure Wustite (FeO) and Iron sulfide (FeS), the eutectic temperature is 940^oC.

Source

NIST doesn't mention this because only one piece of steel from the WTC Towers shows this behavior, and it could have happened after collapse. Also, the temperatures seen in this piece of steel -- 850^oC or less -- are easily within those predicted by NIST. You're just plain wrong.

In fact, NIST makes no allowance at all, at all for molten steel under any conditions--even though we have undeniable, public confirmation of such. Not only is the WPI steel evidence of molten steel, but, more strangely, it is evidence of an uncommon "eutectic" reaction whose likelihood of happening willy-nilly is less parsimonious than an artificial reaction.

No. The WPI steel is evidence against molten steel. Temperatures of only 940^oC would have destroyed the eutectic mixture, and this is way, way below the melting temperature of steel. This is evidence of an interesting chemical reaction, but not great heat or melted steel.

And while we're on it, the existence of ferrous microspheres must also be taken into account since the existence of such has been corroborated by the USGS.

This may turn out to be fodder for another thread, but the point remains that NIST scientists are either not capable or unwilling to even consider these pieces of evidence.

Speculation on your part. It hasn't been proven that these microspheres require anything unusual at all. There is also no evidence or precedent that they contributed to the collapse.

To label them "outside the scope of the NIST report" is to admit failure of the NIST project. This is irrefutable evidence of molten steel, not just aluminum. To say "molten steel bears no relevance to the possible collapse sequence of a steel and concrete structure" is to talk nonsense.

There is no evidence of "molten steel." None. Case dismissed.

 

[R.Mackey]

Regardless of what Mackey says about chaotic systems that are impossible to model, gravity is always strictly inforced. Also, every time something is deflected it loses momentum. I challenge anyone to come up with a realistic scenario by which a debris component actually hits a floor truss on the south side of the building while retaining enough momentum to damage the foreproofing.

Nice strawman.

I already came up with such a scenario, based on fluid dynamics. I also feel comfortable saying that, in all likelihood, everyone reading this thread -- except you -- understands that over a timescale of under half a second, gravity is negligible in the dynamics of an aircraft impact. If you don't believe me, estimate the Froude number and see what you get.

 

[Gravy]

Another detailed, informative, and factually correct smackdown by R. Mackey. Jay, his advice is good. There is no excuse for arguing from ignorance. The information to answer your questions is available to all. You only have to read it and not misrepresent what you've read.

 

[Gravy]

If anyone can find such a scenario, then try to come up with the probability that a significant portion of the debris will follow this trajectory.

Translation: "I challenge anyone to write the NIST report."