flyingswan on Apr 25 2008, 08:39 PM, said:
I was just suggesting that you restricted the AE911T list to those actually capable of evaluating the "official" theory. Structural and fire engineers. How many can they muster?
So, by your own reckoning, you are incapable of evaluating the NIST ‘investigation’?
It may take structural or fire engineers to put together detail of the ‘investigation’ but it by no means requires an expert to understand the preconceptions, political restrictions, lack of evidence, fixing and stretching of figures that went into it, altogether still failing to prove the impacts could even initiate the collapses on 9/11.
The 300+ members of Architects and Engineers for 9/11 Truth are capable of making all the above observations, as can any inquisitive person who looks into it, and more.
flyingswan on Apr 25 2008, 08:39 PM, said:
Kevin Ryan was fired by UL for using UL's name to promote his personal opinions.
Steven Jones was put on paid leave for similar reasons. The engineers at his university have denounced his theories (did you count those?).
James Quintiere questions some of the details of the NIST findings, but has said that there is no evidence for CD. Count him on the anti-CD side too.
Of five AE911T names picked at random, only one appeared to actually exist. This suggests that your 300+ professionals actually number rather less. This is not a conspiracy theory on my part, I have no idea whether the false names on the list are people trying to discredit AE911T or conspiracists trying to push up the numbers.
Yes, the first two are fine examples that you are not allowed to publicly voice personal opinions as an employee of these organisations. A couple of quotes from NIST’s former Chief of Fire Science, James Quintiere: -
- “In my opinion, the WTC investigation by NIST falls short of expectations by not definitively finding cause, by not sufficiently linking recommendations of specificity to cause, by not fully invoking all of their authority to seek facts in the investigation, and by the guidance of government lawyers to deter rather than develop fact finding.”
- “I think the official conclusion that NIST arrived at is questionable”
Now just two questions: -
- Would Quintiere have publicly stated the above if still an employee of NIST?
- How long would Quintiere remain in his current position at the University of Maryland if he suggested anything other than the impacts caused the collapses?
Which five AE911 names were picked and how did you attempt to validate their existence? I looked at the checks badeskov carried out but those three names are not listed either with Architects and Engineers, Scholars or Patriots for 9/11 Truth.
flyingswan on Apr 25 2008, 08:39 PM, said:
Fact is, that video is the only evidence you have of a thermite column cutter, and you seem unable to give any example of a larger one working. In the absence of any other evidence, scaling up from that video is all you can do. I showed on the long thread that you would have to scale such a device linearly with the dimensions of the column.
Given also that the video is by way of being a demonstration, I'd be very surprised if they cut a small column when a bigger and more impressive column was possible.
I don't know where you got only two hundred kg for the cascade. Estimates I've seen range from several hundred kg to tonnes. Even on your figures, a device a metre long is pretty noticable, certainly impossible to hide under spray-on insulation.
It is only your opinion that the device would need to be scaled up in direct proportion to the column… not surprising as you are not exactly one for having a ‘can do’ attitude. You did not show in the other thread that increasing the dimensions of the device does not increase its effectiveness disproportionately.
The WTC2 thermite flow is not at all easy (impossible even?) to quantify so how it can be shown to be more than a couple of hundred kg I don’t know. In
this clip where they burn through a car engine I would say, judging by the flowerpot size, there is approximately 17kg of thermite – well I’m allowing for approximately 12 times the amount seen in the video. How can you say with any certainty there is more than this in the WTC2 flow?
flyingswan on Apr 25 2008, 08:39 PM, said:
As you say, photographic evidence. NCSTAR 1-6D, p324, for example.
The photographs show damage to the WTC2 floors in the area of impact. I am asking for evidence that the floor trusses were sagging due to fire, in particular in the case of WTC1. There isn’t any evidence, is there? This sagging floor theory is all just a charade to cover that the WTC1 bowing was in the wrong place to be explained by the impacts, ie the WTC2 bowing was toward the damage area (all well and good) whilst the WTC1 bowing was away from the damage area (not so good).
flyingswan on Apr 25 2008, 08:39 PM, said:
Sorry to disillusion you, but structures frequently behave like that, particularly steel structures failing through buckling of columns. At first just a little bowing, then suddenly the whole thing goes. Once a column bows sufficiently to be unable to support its load, that's it. Further bowing means even less load capacity, so you have a positive feedback situation
I have given an example in the Windsor building of where severe and widespread distortion of the structural steel is clearly visible prior to even a partial collapse. Are there any examples you can provide where a building in its entirety collapses virtually symmetrically after a column or limited columns exhibit bowing?
They used the LS-DYNA code, a widely used structural simulation package. That is in the summary of the paper if you bother to read it.
http://www.ansys.com/products/lsdyna.aspYou may find the Chinese paper funny, but then you found "real structures aren't rigid" equally funny. Laughing at something you don't understand is hardly a route to truth. Fact remains, it is an engineering simulation of the collapse using a standard engineering tool.
You are obviously aware of B&Z, and there's a recent paper by Seffen in J Eng Mech that also analyses the collapse.
In which case, the impacts were not correctly modelled: -
The actual WTC1 ‘upper block’ is approximately a cube whilst the simulation shows the impact a considerable distance lower down, don’t you agree?
B&Z did not produce a simulation, just figures making assumptions in favour of collapse and leaving out energy requirements. There was a New Civil Engineer article entitled “
WTC investigators resist call for collapse visualisation” and NIST themselves have stated they are “unable to provide a full explanation of the total collapse”. Certainly Purdue’s pancake collapse visualisation was a farce. As discussed above, the Chinese ‘simulation’ is a joke.
So come on, you said you know what a ‘natural’ collapse should look like due to the simulations - where are these simulations that you have seen and no one else has?
That's new, when did you claim that?
New?
…...
QUOTE (Q24 @ Oct 11 2007 to Apr 20 2008)
There was no reason for demolishing the penthouse; its collapse was simply a by-product of the structure weakening local to the top of WTC7.
...
I said a few pages back the demolition/cutting charges were to weaken the upper floors of WTC7 to ensure a complete collapse occurred. A collapse of the penthouse was not the specific intention but a by-product of this weakening.
...
I believe it likely that the penthouse structure coming down seconds before the main collapse was not a design of the demolition but simply an effect of the initial high level charges used to weaken the building before the main charges caused complete collapse.
I have noticed, often you resurrect ‘problems’ of the controlled demolition or points for the ‘official’ story that have been debunked before and many times I have wondered if you have retained any information from previous discussions. This demonstrates that you do not in fact retain the information. There are all sorts of reasons for memory loss, including dementia, head injury and aging but there is help available for it you know.
Say what you like, I'm an engineer, you're not, so why should I take any notice of your mere opinions on engineering matters?
Why should I take any notice of someone who displays the tell-tale signs of dementia?
You completely misunderstand this process - they apply a force to see how large a force corresponds to how big a bowing displacement. They do not "predict" anything, this is a calibration exercise.
You said earlier, “
It fits it very well, not just predicting bowing as a phenomenon, but correctly predicting its location too.” Whilst you argue with yourself about whether there was a prediction or not, I will state with certainty that NIST added pull-in forces specifically to the south wall in an attempt to match with the observed photographic evidence.
Read the page again. They say that a lesser force would produce enough bowing when combined with the vertical load redistribution. They do not say that the actual bowing is impossible to model.
Once they have a fire and damage model, they use this to predict where and when the floors are likely to sag, hence where to apply pull-in forces.
No, they apply pull-in forces specifically to the south wall and nowhere else and then remove truss connections where they find appropriate to imitate the bowing.
I can’t see where NIST say a lesser force would produce the observed or “enough” bowing – can you quote it? If the actual degree of bowing is possible to model then why don’t they do so?
You have been proved wrong in your contentions that load redistribution should be uniform, that structures are not elastic, that the bowing wasn't real, that column-to-column impact is not a conservative assumption, that no structural engineer would believe my theory of a hidden internal collapse of WTC7 preceding the visible one.
I have never said that load redistribution must be uniform, I contend that the WTC structures were not as elastic as you imply, I still do not agree that “
all the impact forces go into the columns” is conservative and I don’t believe low level fire could collapse the penthouse structure down ‘through’ WTC7.
On the contrary, Gilsanz has given an explanation that fits the key piece of evidence that makes the WTC7 collapse unlike a CD. Beam thermal stresses in a fire are enough to push or pull a column out of vertical. I have no reason to doubt that a failure of column 79 is at all implausible given that the building had been on fire for hours. The "removal" you mention is merely the standard way of representing a failed element in a structural model. Once it has failed, it cannot support a load, so you remove it to model this fact. The structure did not have enough redundancy, given the fire and damage, to carry the redistributed load from column 79, so an internal collapse followed, progressive to the west so also bringing down the west penthouse.
If you think an internal collapse is impossible, check out what happened to WTC5.
Column 79 was surrounded by horizontal beams on all sides from the ground to the roof so it would be more likely to fail in compression if due to heating, and as we know this can actually increase the steel strength. Even if the column fails there are still connections with the beams so the penthouse structure could not simply ‘fall through’ the building.
What is the redistributed load you mention after the failure of column 79? As this whole section of the structure had allegedly been removed or collapsed before the rest in your theory, it would have
relieved the remaining structure of the penthouse load.
If all this ‘hollowing out’ of the structure occurred on the east side, I still want to know why all the columns on the west simultaneously and virtually symmetrically failed at near freefall.
WTC5 took a massive hit from WTC1 debris and did not collapse.
Ross's momentum analysis shows a lot of available energy, more actually than Ross guesses for the concrete pulverisation and steel strains, and this is the source of the energy for those phenomena. By adding in a separate estimate for this energy, Ross does indeed count it all twice.
I don’t think you know what you’re talking about. The available energy is never “
more actually than Ross guesses for the concrete pulverisation and steel strains”. Here are Ross’ figures: -
Energy Summary:
The energy balance can be summarised as
Energy available;
Kinetic energy 2105MJ
Potential energy Additional downward movement 95MJ
Compression of impacting section 32MJ
Compression of impacted section 24MJ
Total Energy available 2256MJ
Energy required;
Momentum losses 1389MJ
Plastic strain energy in lower impacted storey 244MJ
Plastic strain energy in upper impacted storey 215MJ
Elastic strain energy in lower storeys 64MJ
Elastic strain energy in upper storeys 126MJ
Pulverisation of concrete on impacting floor 304MJ
Pulverisation of concrete on impacted floor 304MJ
Total Energy required 2646MJ
Minimum Energy Deficit -390MJ
Where does he double count anything?
Do I really need to spell it out? Turbonium uses HE charges because they are easy to hide, you use thermite to explain the lack of explosive noises just before the collapse. Thermite isn't easy to hide, HE is noisy. Neither explains the combination of a "quiet" CD with easily hidden charges, which is what you both actually need. Neither of you has an adequate CD theory.
The explosive charges are detonated prior to the main collapse to weaken the structure (heard in numerous videos), the thermite charges are used to initiate the collapse. Turbonium has already pointed out that your perceived misgivings of what is easy or not to conceal is neither here nor there; the important factor is the possibility of the setup.
Edited by Q24, 27 April 2008 - 12:14 AM.
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