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Post  Post subject: Re-investigation of 9/11 Events  |  Posted: Mon Oct 03, 2011 5:02 pm
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Slightly off topic: One thing I would do is assign a new independent investigation of the events of 9/11 (particularly investigating the collapse of WTC-7 and the discovery of steel microspheres and thermitic residues in the steel core column remains and other debris) to the entire academic community of structural engineers, physicists, chemical engineers, fire protection engineers, architects etc. It needs to be re-investigated, the evidence shown by "architects and engineers for 9/11 truth" just shouts this out.


MOD NOTE: This thread was split from US Politics: King for a Day

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Last edited by iNow on Mon Oct 10, 2011 7:24 pm, edited 1 time in total.
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wireless
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Tue Oct 04, 2011 9:14 am

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x(x-y) wrote:
Slightly off topic: One thing I would do is assign a new independent investigation of the events of 9/11 (particularly investigating the collapse of WTC-7 and the discovery of steel microspheres and thermitic residues in the steel core column remains and other debris) to the entire academic community of structural engineers, physicists, chemical engineers, fire protection engineers, architects etc. It needs to be re-investigated, the evidence shown by "architects and engineers for 9/11 truth" just shouts this out.


You will find yourself on a long and rewarding mission if you get into the conspiracy theories surrounding 9/11. I wish you luck. :)


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x(x-y)
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Tue Oct 04, 2011 3:37 pm
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"Long and rewarding"? It's difficult to tell over the Internet whether you're being sarcastic or not! However, I do not like to call them "conspiracy theories", rather they're better off just called "scientific hypotheses"- I support the hypothesis of "controlled demolition" of the 3 towers (WTC-7 was the smoking gun) as it has a lot of evidence going for it, as well as several hundred experts such as Steven Jones (PhD Physics), Robert Bowman (PhD Finite Element Analysis) etc supporting it.

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wireless
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Tue Oct 04, 2011 11:02 pm

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x(x-y) wrote:
"Long and rewarding"? It's difficult to tell over the Internet whether you're being sarcastic or not! However, I do not like to call them "conspiracy theories", rather they're better off just called "scientific hypotheses"- I support the hypothesis of "controlled demolition" of the 3 towers (WTC-7 was the smoking gun) as it has a lot of evidence going for it, as well as several hundred experts such as Steven Jones (PhD Physics), Robert Bowman (PhD Finite Element Analysis) etc supporting it.


Gentle sarcasm most definitely. The amount of stuff out in cyberspace supporting the conspiracy theorists concerning 9/11 is mind boggling, you will most definitely find what you want hear. In the murder and mayhem that was the result of 9/11, I can never believe that the American Government instigated this. Conspiracy theories yes, scientific hypothesis no.


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x(x-y)
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Wed Oct 05, 2011 4:09 pm
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And you base this on what exactly? The NIST final reports of the tower collapses which states that the WTC-1, WTC-2 and WTC-7 towers collapsed vertically through tens of thousands of tonnes of structural steel at rates approaching free fall acceleration (with air resistance of course) due to fires which burnt below the plastic deformation range of the structural steel? Do you honestly think that office fires in WTC-7 caused its complete collapse?

Sure, there are some crazy conspiracy theories out there about 9/11, however you cannot tar all hypotheses with the same brush- the controlled demolition hypothesis has a lot of papers and hundreds of experts backing it; and it most certainly does not imply that the US government instigated the entire 9/11 operation, it just takes the science of the situation and analyses it no conspiracy theories involved. Go onto the "Architects and Engineers for 9/11 Truth Website".

So, conspiracy theory? Definitely not. Scientific hypothesis? Definitely.

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iNow
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Wed Oct 05, 2011 5:21 pm
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x(x-y) wrote:
the controlled demolition hypothesis has a lot of papers and hundreds of experts backing it;

How did the demolition materials get placed in all of the right places without being noticed? There are countless security, inspection, maintenance teams, elevator crews, or computer and network techs who install and fix wires and cables behind the walls... These folks survey those areas daily and might just notice the (what would have to be) several tons of thermite suddenly appearing.

How did those people placing the materials escape the notice of all workers and staff during the (what has to be) weeks or months it would take to place enough material into the structure to cause such an event?

How did they know in advance into which floors the planes would collide in order to place the demolition materials in the correct locations and altitudes?

Why did they use thermite, when shaped charges are much better and don't leave traceable residues?

Further, if it was thermite, we'd see sparking everywhere, and we did not. There is no evidence of explosives, there was no explosion on any video, no nitrated esters, etc.

You also wonder about the downward fall of the building... Look at the square/cube law in architecture and explain how it could have fallen any other way. Buildings don't tip over like trees, sorry... They are not even close to rigid enough to do that, and the moment it started to fall it would just buckle, and fall straight downward anyway (since gravity pulls downward, not laterally).

Explosives are not required to get buildings of that size to fall down, and a building collapses downward into itself, it doesn't topple like an uprooted tree. There is no need to invent an explanation when the simpler one fits the circumstances just fine. Planes crashed into the buildings, structural components became thermally soaked, and failed.

AFAIC, this idea doesn't even begin to pass the stink test... or, should I say, it cannot stand up to even remedial peer review.

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x(x-y)
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Wed Oct 05, 2011 6:46 pm
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iNow:

1) Upon construction of the building, workers may have placed components containing thermite explosives next to the core columns without themselves noticing- they can be quite easily hidden in building components.

2) Electrical engineers had 24/7 access to the elevator shafts of all WTC towers, which were conveniently right next to the steel core columns. Any organisation capable of using enough thermite to bring a building down could easily sneak agents into the buildings at night under the fake identity of an electrical engineer to place the thermite.

3) WTC-7 was not hit by a plane and so the third question has no relevance to that, as for WTC-1 and WTC-2- it really doesn't matter where you place the explosives as long as they are in contact evenly with the central core columns, that building will come down vertically.

4) Shaped charges most certainly will leave traceable residues by the fact that they make use of superheated plasmas melting through the supports, they will leave residues of elements and compounds formed in superheated conditions. And, why not use thermite? NIST claimed in their report "WTC-7 was not brought down by explosives", then when asked by "A&E for 9/11 Truth" is turns out that they never even tested for explosives or residues of explosives- so they didn't test for it because they didn't expect it, that is the most unscientific thing you can possibly think of!

5) No evidence of thermite?! What about the steel microspheres? The thermitic residues found in structural steel? The clear angled cuts in the remaining core columns? The melted iron so clearly pictured flowing from the top of WTC-1 and -2? The list goes on.

6) Buildings always fall towards the section of damage, unless if another agent such as precisely placed explosives are used to control the fall of the building- the damage was not uniform across any of the towers yet they all fell in an almost exact match. NIST says that piledriving of "a rigid body top" of WTCs 1 and 2 caused the downward fall of the buildings- well, where is the jolt from the inertial mass of the thousands of tonnes of material below? How does the top gain enough momentum to piledrive through all the below floors when it cam clearly be seen that they disintegrate before even impacting the bottom section? Why did WTC-1 fall for over 100 ft at the acceleration of free fall of an object in air resistance? These questions are unanswered by NIST.

7) Again, WTC-7 was not hit by a plane. NIST claims that it failed due to "office fires"- that's a load of nonsense. In the entire history of construction, not a single structural steel building has collapsed due to fires- office fires in WTC-7 would reach a temperature of around 750°C- way below the required temperature to plastically deform steel let alone melt it.

8) The majority of the fuel of the planes (kerosene by the way) was burnt up in the initial fireball whilst the fires combusting in the building were low temperature- we can see this from the huge amounts of black sooty rich smoke from the towers meaning incomplete combustion and low temperature. Are you telling me that low temperature office fires caused huge elastic/quick plastic deformation of the steel core columns? Unfeasible at best, pseudo engineering at worst.

9) The hypothesis has been peer reviewed by many experts in their fields- Robert Bowman, Richard Humenn, Steve Barasch, Steven Jones etc etc. It has nowhere near been disproven- in-fact, it is pretty darn near to being corroborated with all the papers it has behind it. A quick google search would prove that.

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x(x-y)
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Wed Oct 05, 2011 7:53 pm
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And that's not even to mention the ridiculous statement made by NIST as their excuse to not release the input data and parameters into their computer model animation of the collapse of WTC-7, they said that it would "jeopardise public safety". How on Earth would releasing model input data "jeopardise public safety"? That's just another way of saying, we just made up a load of nonsense. From what I could see of the model anyway, and several experts say this too, it seems that NIST forgot to factor in the floor connections which comprise concrete (for compressional resistance) and steel (for tensional resistance). These connections, holding together the steel core columns and further supporting each floor, have huge resistance- to not factor these into a building collapse model is like not factoring clouds or the ocean into a climate model.

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x(x-y)
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Fri Oct 07, 2011 5:22 pm
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No rebuttal yet, interesting.

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iNow
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Fri Oct 07, 2011 5:57 pm
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x(x-y) wrote:
No rebuttal yet, interesting.

TBH, I really don't give enough of a shit to keep going and engage you point by point. My first response was what I was willing to contribute. I'm satisfied by the conclusion that two planes caused the towers to fall. I'm also okay if you feel otherwise.

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marnixR
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Fri Oct 07, 2011 6:35 pm
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i haven't actually followed this thread very closely - how did we get from a question whether to create jobs or reduce spending to conspiracy theories about the twin towers ? maybe we want to split off that part (if the split can be made fairly cleanly) ?

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iNow
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Fri Oct 07, 2011 7:05 pm
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It's a very clean split if we want to do it. It started right here:

post2340.html#p2340

x(x-y) wrote:
Slightly off topic: One thing I would do is assign a new independent investigation of the events of 9/11...


However, while the current topic is off from the OP, it's inline with the subject. I don't mind keeping it active, as it could turn into a fascinating thread with other concepts... "I'd make coins out of chocolate and have every Friday be for massages," that sort of thing.

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marnixR
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Fri Oct 07, 2011 7:35 pm
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no, carry on - if you're of the opinion that it's within the subject that's ok with me

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x(x-y)
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Fri Oct 07, 2011 7:58 pm
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Ah, sorry for altering the thread course- I just wanted to get that point in there, it seems sort of relevant anyway.

As a reply to iNow: Exactly, that is what is disturbing- people seem to have been spoon-fed the "official story" (which is simply wrong as seen by the just a small amount of evidence I posted earlier) and are showing signs of serious cognitive dissonance of an unwillingness to listen to different hypotheses.

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DrRocket
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Fri Oct 07, 2011 8:16 pm
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iNow wrote:
x(x-y) wrote:
No rebuttal yet, interesting.

TBH, I really don't give enough of a shit to keep going and engage you point by point. My first response was what I was willing to contribute. I'm satisfied by the conclusion that two planes caused the towers to fall. I'm also okay if you feel otherwise.


On the other hand, if you succeed in convincing a conspiracy theorist of the lack of substance in his pet hallucination, it will be quite an accomplishment. I have not yet seen it done.

The twin towers attack has been analyzed and re-analyzed by people who actually understand structures, explosives and pyrotechnics. The conspiracy theories are without merit.

How about tiny pink pixies with cutting torches ?

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Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Fri Oct 07, 2011 8:57 pm
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What a fascinatingly intellectual comment!

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iNow
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Fri Oct 07, 2011 10:06 pm
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To the OP, I would invest and stimulate the economy, as reduction of spending will do more harm than good in the immediate term.

To the thread title, I'd use the bailout money given to banks and direct it to reduce household debt and student loan obligations, and I'd implement a short term trading transaction tax.

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kojax
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Mon Oct 10, 2011 5:21 pm
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I'm hoping a mod will split out all the 911 stuff into its own thread or something...

DrRocket wrote:
iNow wrote:
x(x-y) wrote:
No rebuttal yet, interesting.

TBH, I really don't give enough of a shit to keep going and engage you point by point. My first response was what I was willing to contribute. I'm satisfied by the conclusion that two planes caused the towers to fall. I'm also okay if you feel otherwise.


On the other hand, if you succeed in convincing a conspiracy theorist of the lack of substance in his pet hallucination, it will be quite an accomplishment. I have not yet seen it done.

The twin towers attack has been analyzed and re-analyzed by people who actually understand structures, explosives and pyrotechnics. The conspiracy theories are without merit.

How about tiny pink pixies with cutting torches ?


Have you actually looked into Stephen Jones? Graduated Magna Cum Laude in physics from BYU, went on to specialize in particle physics. Holds the record for Muon production. This is not a hack. He is a smart guy who's genuinely convinced of what he sees.

The thing with steel microspheres was a while ago. Since then he's found what appears to be actual undetonated residue from nano-thermite. That is to say red/gray strips of material composed of particles of aluminum and iron of a small diameter that would be very difficult to create, even on purpose, without advanced tools, and which creates the expected amount of heat when burned.

http://www.benthamscience.com/open/tocp ... 7TOCPJ.htm


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DrRocket
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Mon Oct 10, 2011 6:02 pm
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kojax wrote:
Have you actually looked into Stephen Jones? Graduated Magna Cum Laude in physics from BYU, went on to specialize in particle physics. Holds the record for Muon production. This is not a hack. He is a smart guy who's genuinely convinced of what he sees.

The thing with steel microspheres was a while ago. Since then he's found what appears to be actual undetonated residue from nano-thermite. That is to say red/gray strips of material composed of particles of aluminum and iron of a small diameter that would be very difficult to create, even on purpose, without advanced tools, and which creates the expected amount of heat when burned.

http://www.benthamscience.com/open/tocp ... 7TOCPJ.htm


I am not even slightly impressed by the BYU physics program, Steven Jones, or the paper.

I would be amazed if one did not find aluminum and iron even of small diameter in the collapse of such a large building. If it did not burn with the expected heat output we would need a new periodic table.

http://www.physics.byu.edu/research/energy/

You may have your own definition of "a hack", but Jones fits mine. He was one of the instigators of the coldv fusion fiasco of the 80's. In fact it was an imminent publication by Jones and issues of priority and patent rights that caused Pons and Fleischmann, at the insistence of legal counsel, to jump the gun and make their fateful announcement. While I have inhdependent knowledge, you can find much of this documented in Bad Science by Gary Taubes.

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x(x-y)
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Mon Oct 10, 2011 6:30 pm
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DrRocket wrote:
I am not even slightly impressed by the BYU physics program, Steven Jones, or the paper.


I'm not too sure if Jones would be impressed by this comment either, but that's beside the point.

DrRocket wrote:
If it did not burn with the expected heat output we would need a new periodic table.


If what did not burn with what expected heat output? The fires that burned in the towers of WTC-1, 2 and 7? By the very fact that you can see huge amounts of black smoke pillowing from the fires means that there was incomplete combustion and thus low temperature fires- also, kerosene doesn't burn at a temperature anywhere near the plastic deformation energy limit of steel let alone the melting point- so why do we see rivers of melted iron and steel at the bases of the towers after collapse? And why did we see molten iron (yellow-orange) pouring from the crash site in WTC-1 and WTC-2?

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iNow
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Mon Oct 10, 2011 7:27 pm
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marnixR wrote:
maybe we want to split off that part (if the split can be made fairly cleanly) ?

kojax wrote:
I'm hoping a mod will split out all the 911 stuff into its own thread or something...

Done.

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DrRocket
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Mon Oct 10, 2011 8:57 pm
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x(x-y) wrote:
If what did not burn with what expected heat output? The fires that burned in the towers of WTC-1, 2 and 7? By the very fact that you can see huge amounts of black smoke pillowing from the fires means that there was incomplete combustion and thus low temperature fires- also, kerosene doesn't burn at a temperature anywhere near the plastic deformation energy limit of steel let alone the melting point- so why do we see rivers of melted iron and steel at the bases of the towers after collapse? And why did we see molten iron (yellow-orange) pouring from the crash site in WTC-1 and WTC-2?



Utter nonsense.

You ought to get some experience and learn a few things before mouthing off about a subject about which you know nothing.

Black smoke coming from a building fire tells you prrecisely nothing about local temperatures. There are a great many materials undergoing combustion, and the availability of oxygen is hardly uniform.

The plastic deformation of steel is determined by the applied stress and the material allowable. The material allowable is temperature dependent, but any fool knows that it quite possible to plastically deform steel at ambient temperature, let alone at significantly elevated temperature. Once one gets significant deformation, geometric non-linearity and buckling take over.

The adiabatic flame temperature of kerosene (3801 F) is quite sufficient to soften steel, and in a confined situation, such as the burning World Trade Center after some time for things to heat up, would provide the necessary high temperature environment. While the applied temperature would be substantially less than the adiabatic temperature, which is well above the melting point of steel (2500-2700 F depending on alloy), it would be sufficient to soften a large body of steel and perhaps produce local melting. Any burning metal, such as aluminum, would serve to increase the temperature dramatically -- and yes aluminum burns readily in the proper circumstances (ask the Brits about superstructures in the Falkland war or note that aluminum ias used in high performance solid rocket propellants).

The high adiabatic flame temperature of kerosene is one reason why it is used as a rocket fuel.

http://www.doctorfire.com/flametmp.html

http://en.wikipedia.org/wiki/Adiabatic_ ... emperature

http://www.muggyweld.com/melting.html

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marnixR
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Mon Oct 10, 2011 9:16 pm
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considering that at around 500°C you have exceeded the recrystallisation temperature of structural steel, a structure will collapse under its own weight
also, any strengthening of the steel through either normalising or quench-and-tempering will have been undone in an irreversibly fashion

hence it doesn't take extreme heat to make a steel-supported structure collapse, merely prolonged exposure to moderate heat

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x(x-y)
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Mon Oct 10, 2011 9:28 pm
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There's no need to be rude and obtuse (DrR) but anyway- I shall not throw insults around as such an action is not constructive in the slightest.

So, here is my plan of action (a heads-up just so you know that I haven't given up on this thread)- in my next post I shall lay out the basis of my arguments and the details of why I think that WTC-1, WTC-2 and WTC-7 did not collapse ultimately due to fire. It shall be a long post and will take me a while, possibly weeks rather than days- so hang fire until then!

NB: I am not concerned with the conspiracy theories of an inside job, all I shall focus on is "how those towers came down" because to think that 3 structural steel skyscrapers collapsed completely into their own footprint in one day due to to fire is completely absurd and ridiculous as such a thing has never happened before in the history of construction- and then 3 in 1 day? No, its ridiculous- so the collapsing will be the topic of my next post, not the conspiracy theories.

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x(x-y)
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Mon Oct 10, 2011 9:30 pm
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marnixR wrote:
considering that at around 500°C you have exceeded the recrystallisation temperature of structural steel, a structure will collapse under its own weight
also, any strengthening of the steel through either normalising or quench-and-tempering will have been undone in an irreversibly fashion

hence it doesn't take extreme heat to make a steel-supported structure collapse, merely prolonged exposure to moderate heat


Just one comment (my next post shall be the long one) about this: you do know that the structural steel core columns at the bottom of WTC-1 and WTC-2 were designed to support 5x their weight?

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15uliane
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Mon Oct 10, 2011 9:38 pm
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That's cool!

Hopefully that's just a funfact because it does nothing for your argument- the debris and planes did not hit at the base.


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marnixR
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Mon Oct 10, 2011 9:40 pm
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x(x-y) wrote:
Just one comment (my next post shall be the long one) about this: you do know that the structural steel core columns at the bottom of WTC-1 and WTC-2 were designed to support 5x their weight?


you're referring to cold strength, which is irrelevant once a metal (any metal) has exceeded its recrystallisation temperature, since it will then collapse under its own weight

it's one of the reason why lead can't be used for load-bearing applications, at room temperature it already exceeds its recrystallisation temperature

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DrRocket
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Mon Oct 10, 2011 10:03 pm
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x(x-y) wrote:
There's no need to be rude and obtuse (DrR) but anyway- I shall not throw insults around as such an action is not constructive in the slightest.

So, here is my plan of action (a heads-up just so you know that I haven't given up on this thread)- in my next post I shall lay out the basis of my arguments and the details of why I think that WTC-1, WTC-2 and WTC-7 did not collapse ultimately due to fire. It shall be a long post and will take me a while, possibly weeks rather than days- so hang fire until then!

NB: I am not concerned with the conspiracy theories of an inside job, all I shall focus on is "how those towers came down" because to think that 3 structural steel skyscrapers collapsed completely into their own footprint in one day due to to fire is completely absurd and ridiculous as such a thing has never happened before in the history of construction- and then 3 in 1 day? No, its ridiculous- so the collapsing will be the topic of my next post, not the conspiracy theories.


So farbas I know, 100% of buildings that have been hit by a modern fuel-laden commercial jet have collapsed.

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DrRocket
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Mon Oct 10, 2011 10:15 pm
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marnixR wrote:
x(x-y) wrote:
Just one comment (my next post shall be the long one) about this: you do know that the structural steel core columns at the bottom of WTC-1 and WTC-2 were designed to support 5x their weight?


you're referring to cold strength, which is irrelevant once a metal (any metal) has exceeded its recrystallisation temperature, since it will then collapse under its own weight

it's one of the reason why lead can't be used for load-bearing applications, at room temperature it already exceeds its recrystallisation temperature


Steel is often recrystallized on purpose -- the process is annealing. It does not then "collapse under its own weight", but it does lose strength that it may have gained by means of heat trreatment, though it generally gains ductility. However, the structural steel used in buildings is usually mild steel, basically annealed. The major factor would be loss of strength at elevated temperature, which can be significant. There is also the issue of assymetric heating of the steel structure which can induce thermal stress and warp the structure leading to geometric non-linear loading scenarios and buckling.

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mississippichem
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Tue Oct 11, 2011 12:53 am
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500°C also coincides with the temperature at which pure iron undergoes its alpha-beta phase transition. Both phases are solid but the beta phase is in fact more ductile. Steel is a bit of a different story. Steel is notorious for a fairly messy stoichiometry and there a highly disorded lattice. I wouldn't be surprised if some of that alpha-beta phase transition character manifests itself in steel as a near 500°C maximum recrystalization temperature.

All that to say I completely agree.


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kojax
Post  Post subject: Re: US Politics: King for a Day - What would you do?  |  Posted: Tue Oct 11, 2011 1:00 am
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I don't think a formal controlled demolition would be necessary to bring the buildings down the way we saw them fall, but there are other issues. The fires in building #2 were mostly concentrated on the East side, where the plane had hit it. The West side didn't get nearly as much fire, and retained its fire proofing. How do we get a symmetrical collapse out of a very lopsided fire? The fires in building #1 were more evenly distributed, though they were also close to the point of going out when the building fell. Just bad luck that it couldn't hold out just a bit longer guess? But it's hard to see how such very different fires could lead to such very similar collapses.

This is from an NIST document entitled "Reconstruction of the Fires in the World Trade Center Towers." Unfortunately my link to it is broken now. It's a 50 mb PDF file, which I fortunately managed to download before they moved (or removed?) it. I'll be happy to try and send it to anyone who wants it, if my email can handle it.

NIST report on the fires page xlix wrote:
"In WTC 1, if the fires had been allowed to continue past the time of building collapse, complete burnout would likely have occurred within a short time since the fires had already traversed around the entire floor and most of the combustibles would already have been consumed.


NIST report on the fires E.8.2 (The page after the last quote) wrote:
The major fires in WTC 1 were on the 93rd through 99th floors. The fires generally moved both clockwise and counterclockwise from the north to the south of the tenant spaces. The fires were generally ventilation limited, i.e., they burned and spread only as fast as fresh air became available, generally from additional window breakage.

The major fires in WTC 2 were on the 79th through 83rd floors, with the most significant fires being in the northeast corner of the 81st and 82nd floors. The fires had sufficient air to burn at a rate determined by the properties of the combustibles. This was in large part due to the extensive breakage of windows in the fire zone by the aircraft impact."


Also in both cases, the plane managed to impact in the dead center of a multi floor tenancy. In WTC 1, the center of impact was the 96th floor. (Marsch and McLennon occupied floors 93-100) In WTC 2, the center of impact was between the 80th and 81st floor. (Fuji Bank occupied floors 79-82) If a demolition were planned to be set up near the point of impact to "enhance" the damage and make sure the building did in fact fall, it would only require accomplices from 2 tenants.

http://en.wikipedia.org/wiki/List_of_te ... ade_Center
http://en.wikipedia.org/wiki/List_of_te ... ade_Center

DrRocket wrote:
kojax wrote:
Have you actually looked into Stephen Jones? Graduated Magna Cum Laude in physics from BYU, went on to specialize in particle physics. Holds the record for Muon production. This is not a hack. He is a smart guy who's genuinely convinced of what he sees.

The thing with steel microspheres was a while ago. Since then he's found what appears to be actual undetonated residue from nano-thermite. That is to say red/gray strips of material composed of particles of aluminum and iron of a small diameter that would be very difficult to create, even on purpose, without advanced tools, and which creates the expected amount of heat when burned.

http://www.benthamscience.com/open/tocp ... 7TOCPJ.htm


I am not even slightly impressed by the BYU physics program, Steven Jones, or the paper.

I would be amazed if one did not find aluminum and iron even of small diameter in the collapse of such a large building. If it did not burn with the expected heat output we would need a new periodic table.

http://www.physics.byu.edu/research/energy/


Do you mean to imply that you've perused the paper? They claimed to find red/gray chips in dust recovered from the surrounding area after the collapse.

The Paper wrote:
The
red/gray chips are attracted by a magnet, which facilitates
collection and separation of the chips from the bulk of the
dust. A small permanent magnet in its own plastic bag was
used to attract and collect the chips from dust samples. The
chips are typically small but readily discernible by eye due to
their distinctive color.

....

All of the chips used in the study had a gray layer and a
red layer and were attracted by a magnet.


Part about Particle size wrote:
At still higher magnifications, BSE imaging of the red
layer illustrates the similarity between the different dust
samples. BSE images of small but representative portions of
each red-layer cross section are shown in Fig. (8). The results indicate that the small particles with very high BSE
intensity (brightness) are consistently 100 nm in size and
have a faceted appearance. These bright particles are seen
intermixed with plate-like particles that have intermediate
BSE intensity and are approximately 40 nm thick and up to
about 1 micron across.


The theory of the paper is that these chips are part of the outer casing of the device or devices used, which makes sense because it's not uncommon for components of a bomb to survive the explosion. (At least for conventional bombs.... I don't know if that would also be true for nano-thermite.)

Quote:
You may have your own definition of "a hack", but Jones fits mine. He was one of the instigators of the coldv fusion fiasco of the 80's. In fact it was an imminent publication by Jones and issues of priority and patent rights that caused Pons and Fleischmann, at the insistence of legal counsel, to jump the gun and make their fateful announcement. While I have inhdependent knowledge, you can find much of this documented in Bad Science by Gary Taubes.


I had heard his name associated with that, but I didn't know he was the reason they rushed to publish. Definitely a black spot on the man's career then.


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iNow
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Tue Oct 11, 2011 1:06 am
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It even has a wiki:

http://en.wikipedia.org/wiki/World_Trad ... y_theories

Quote:
The World Trade Center controlled demolition conspiracy theory is that the collapse of the World Trade Center was not caused by the plane crash damage that occurred as part of the September 11, 2001, attacks, nor by resulting fire damage, but by explosives installed in the buildings in advance.

Early on, advocates such as physicist Steven E. Jones, architect Richard Gage, software engineer Jim Hoffman, and theologian David Ray Griffin, argued that the aircraft impacts and resulting fires could not have weakened the buildings sufficiently to initiate a catastrophic collapse, and that the buildings would not have collapsed completely, nor at the speeds that they did, without additional energy involved to weaken their structures.

The National Institute of Standards and Technology (NIST) and the magazine Popular Mechanics examined and rejected these theories. Specialists in structural mechanics and structural engineering generally accept the model of a fire-induced, gravity-driven collapse of the World Trade Center buildings, an explanation that does not involve the use of explosives. NIST did not test for explosive compound residue in steel samples, stating the potential for inconclusive results, and noting that similar compounds would have been present during construction of the towers.

In 2006, Jones suggested that thermite or super-thermite may have been used by government insiders with access to such materials and to the buildings themselves, to demolish the buildings. Later, Niels H. Harrit et al. stated that they had found evidence of nano-thermite in samples of the dust that was produced during the collapse of the World Trade Center towers.

In April 2009, Steven E. Jones, along with Niels Harrit and 7 other authors published a paper in The Open Chemical Physics Journal, titled, 'Active Thermitic Material Discovered in Dust from the 9/11 World Trade Center Catastrophe'. NIST then said that there was no "clear chain of custody" to prove that the four samples of dust came from the WTC site. Jones invited NIST to conduct its own studies using its own known "chain of custody" dust, but NIST did not investigate.




Later in the article:

Quote:
The structural engineering community rejects the controlled-demolition conspiracy theory. Its consensus is that the collapse of the World Trade Center buildings was a fire-induced, gravity-driven collapse, an explanation that does not involve the use of explosives.

The American Society of Civil Engineers Structural Engineering Institute issued a statement calling for further discussion of NIST's recommendations, and Britain's Institution of Structural Engineers published a statement in May 2002 welcoming the FEMA report, noting that the report expressed similar views to those held by its group of professionals.

Following the publication of Jones' paper "Why Indeed Did the WTC Buildings Completely Collapse?" Brigham Young University responded to Jones' "increasingly speculative and accusatory" statements by placing him on paid leave, and thereby stripping him of two classes, in September 2006, pending a review of his statements and research. Six weeks later, Jones retired from the university. The structural engineering faculty at the university issued a statement which said that they "do not support the hypotheses of Professor Jones". On September 22, 2005, Jones gave a seminar on his hypotheses to a group of his colleagues from the Department of Physics and Astronomy at BYU. According to Jones, all but one of his colleagues agreed after the seminar that an investigation was in order and the lone dissenter came to agreement with Jones' suggestions the next day.

Northwestern University Professor of Civil Engineering Zdeněk Bažant, who was the first to offer a published peer-reviewed theory of the collapses, wrote "a few outsiders claiming a conspiracy with planted explosives" as an exception. Bažant and Verdure trace such "strange ideas" to a "mistaken impression" that safety margins in design would make the collapses impossible. One of the effects of a more detailed modeling of the progressive collapse, they say, could be to "dispel the myth of planted explosives". Indeed, Bažant and Verdure have proposed examining data from controlled demolitions in order to better model the progressive collapse of the towers, suggesting that progressive collapse and controlled demolition are not two separate modes of failure (as the controlled-demolition conspiracy theory assumes).

Thomas Eagar, a professor of materials science and engineering at the Massachusetts Institute of Technology, also dismissed the controlled-demolition conspiracy theory. Eagar remarked, "These people (in the 9/11 truth movement) use the 'reverse scientific method.' They determine what happened, throw out all the data that doesn't fit their conclusion, and then hail their findings as the only possible conclusion."

Preparing a building for a controlled demolition takes considerable time and effort. The tower walls would have had to be opened on dozens of floors. Thousands of pounds of explosives, fuses and ignition mechanisms would need to be sneaked past security and placed in the towers without the tens of thousands of people working in the World Trade Center noticing. Referring to a conversation with Stuart Vyse, a professor of psychology, an article in the Hartford Advocate asks, "How many hundreds of people would you need to acquire the explosives, plant them in the buildings, arrange for the airplanes to crash [...] and, perhaps most implausibly of all, never breathe a single word of this conspiracy?"

World Trade Center developer Larry Silverstein said, "Hopefully this thorough report puts to rest the various 9/11 conspiracy theories, which dishonor the men and women who lost their lives on that terrible day." Richard Gage, leader of the group Architects & Engineers for 9/11 Truth said, "How much longer do we have to endure the coverup of how Building 7 was destroyed?" James Quintiere, professor of fire protection engineering at the University of Maryland, who does not believe explosives brought down the towers, questioned how the agency came to its conclusions, remarking, "They don't have the expertise on explosives," though he adds that NIST wasted time employing outside experts to consider it.


I've stripped the references to references, but they are in the article.

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kojax
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Tue Oct 11, 2011 3:41 am
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iNow wrote:
It even has a wiki:

http://en.wikipedia.org/wiki/World_Trad ... y_theories

Quote:
In April 2009, Steven E. Jones, along with Niels Harrit and 7 other authors published a paper in The Open Chemical Physics Journal, titled, 'Active Thermitic Material Discovered in Dust from the 9/11 World Trade Center Catastrophe'. NIST then said that there was no "clear chain of custody" to prove that the four samples of dust came from the WTC site. Jones invited NIST to conduct its own studies using its own known "chain of custody" dust, but NIST did not investigate.


That's the paper I cited above.

http://www.benthamscience.com/open/tocp ... 7TOCPJ.pdf

It's funny that NIST's objection would be chain of custody. Do they think someone might have fabricated the nano-thermite chips? Or maybe chips like that just happen to be floating around NYC on any given day?

Quote:
Later in the article:

Quote:
Thomas Eagar, a professor of materials science and engineering at the Massachusetts Institute of Technology, also dismissed the controlled-demolition conspiracy theory. Eagar remarked, "These people (in the 9/11 truth movement) use the 'reverse scientific method.' They determine what happened, throw out all the data that doesn't fit their conclusion, and then hail their findings as the only possible conclusion."

Preparing a building for a controlled demolition takes considerable time and effort. The tower walls would have had to be opened on dozens of floors. Thousands of pounds of explosives, fuses and ignition mechanisms would need to be sneaked past security and placed in the towers without the tens of thousands of people working in the World Trade Center noticing. Referring to a conversation with Stuart Vyse, a professor of psychology, an article in the Hartford Advocate asks, "How many hundreds of people would you need to acquire the explosives, plant them in the buildings, arrange for the airplanes to crash [...] and, perhaps most implausibly of all, never breathe a single word of this conspiracy?"


I don't believe the controlled demolition theory because of the sheer impracticality, but I hate overconstructed arguments. Are we to assume a controlled demolition would be carried out with the full detail, experts, engineers, safety consultants? Maybe call in a building inspector to make sure they rigged the fuses right? Make sure and give their saboteurs health insurance too? Unless discovery is likely, what's to stop a handful of people from setting it up over months? All they need is a bogus work order. Maybe the building's lease owner could write one up?

Floors 2,4,6,18, 30, 43, 64, and 66-74 of WTC 1 were all vacant.
Floors 2-6, 13, 27, and 37 of WTC 2 were all vacant. There were mechanical floors on 41,42,75 and 76.

http://en.wikipedia.org/wiki/List_of_te ... ade_Center
http://en.wikipedia.org/wiki/List_of_te ... ade_Center


If you're not too concerned about getting the collapse exactly perfect, that should give you plenty of places to plant your bombs.

Quote:
Quote:

World Trade Center developer Larry Silverstein said, "Hopefully this thorough report puts to rest the various 9/11 conspiracy theories, which dishonor the men and women who lost their lives on that terrible day." Richard Gage, leader of the group Architects & Engineers for 9/11 Truth said, "How much longer do we have to endure the coverup of how Building 7 was destroyed?" James Quintiere, professor of fire protection engineering at the University of Maryland, who does not believe explosives brought down the towers, questioned how the agency came to its conclusions, remarking, "They don't have the expertise on explosives," though he adds that NIST wasted time employing outside experts to consider it.


I've stripped the references to references, but they are in the article.


It's funny that the article uses Larry Silverstein's statement for its example of public outrage. He also tried to sue his insurance companies for twice the coverage amount, claiming the two planes constituted two separate events. It didn't really work out entirely, but he got a little bit more out of them than he would have got. The policy was two months old (as was his ownership of the WTC lease).

http://en.wikipedia.org/wiki/Larry_Silv ... ce_dispute

wiki Silverstein 911 Insurance Dispute wrote:
The insurance policies obtained in July 2001 for World Trade Center buildings 1, 2, 4 and 5 had a collective face amount of $3.55 billion. Following the September 11, 2001 attack, Silverstein sought to collect double the face amount (~$7.1 billion) on the basis that the two separate airplane strikes into two separate buildings constituted two occurrences within the meaning of the policies. The insurance companies took the opposite view. Based on differences in the definition of "occurrence" (the insurance policy term governing the amount of insurance) and uncertainties over which definition of "occurrence" applied, the court split the insurers into two groups for jury trials on the question of which definition of "occurrence" applied and whether the insurance contracts were subject to the "one occurrence" interpretation or the "two occurrence" interpretation.


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marnixR
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Tue Oct 11, 2011 6:26 am
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DrRocket wrote:
However, the structural steel used in buildings is usually mild steel, basically annealed


presumably you mean carbon steel, which in structural steel is in the order of 0.2-0.25%C, as opposed to mild steel (think car bodies) where it tends to be less than 0.1%C
also notice that when a steel is being annealed, it never is annealed to its lowest strength, merely sufficient to give it sufficient ductility - hence there is still a loss in strength when steel is exposed to high temperatures

see also the wikipedia article on fire resistance of structural steel in buildings

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mississippichem
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Tue Oct 11, 2011 1:07 pm
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marnixR wrote:
DrRocket wrote:
However, the structural steel used in buildings is usually mild steel, basically annealed


presumably you mean carbon steel, which in structural steel is in the order of 0.2-0.25%C, as opposed to mild steel (think car bodies) where it tends to be less than 0.1%C
also notice that when a steel is being annealed, it never is annealed to its lowest strength, merely sufficient to give it sufficient ductility - hence there is still a loss in strength when steel is exposed to high temperatures

see also the wikipedia article on fire resistance of structural steel in buildings


100% correct. Note my comments on page 3.


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DrRocket
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Tue Oct 11, 2011 6:28 pm
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marnixR wrote:
DrRocket wrote:
However, the structural steel used in buildings is usually mild steel, basically annealed


presumably you mean carbon steel, which in structural steel is in the order of 0.2-0.25%C, as opposed to mild steel (think car bodies) where it tends to be less than 0.1%C
also notice that when a steel is being annealed, it never is annealed to its lowest strength, merely sufficient to give it sufficient ductility - hence there is still a loss in strength when steel is exposed to high temperatures

see also the wikipedia article on fire resistance of structural steel in buildings


You presume wrongly.

The term carbon steel applies to a wide variet of steels.

Per Mil-HDBK-5E: "Carbon steels are those steels containing carbon up to about 1 per cent and only residual quantities of other elements except those added for deoxidation."

Mild steel is a form of carbon steel and is the steel normally used in building structures. From
wikipedia :

"Mild steel is the most common form of steel because its price is relatively low while it provides material properties that are acceptable for many applications. Low carbon steel contains approximately 0.05–0.15% carbon[1] and mild steel contains 0.16–0.29%[1] carbon; therefore, it is neither brittle nor ductile. Mild steel has a relatively low tensile strength, but it is cheap and malleable; surface hardness can be increased through carburizing.[3]

It is often used when large quantities of steel are needed, for example as structural steel. The density of mild steel is approximately 7.85 g/cm3 (7850 kg/m3 or 0.284 lb/in3)[4] and the Young's modulus is 210,000 MPa (30,000,000 psi).[5]"

As always, I meant precisely what I said.

I also said, as you now note, that steels suffer a loss in strength (a substantial decrease) at elevated temperature. MIL-HDBK-5E curves for typical low carbon steels show about a 50% loss for bshort-term exposure at 900-1000 F. This has nothing to do with whether or not it was "fully annealed". ANY steel loses strength at elevated temperature.

That does not in any way support your claim that once a piece of steel has been heated above its recrystallization temperature it does not recover to the extent that subsequently it would "collapse under its own weight".


Steel at high temperature loses yield strength and modulus and is subject to buckling, which is precisely what happened when the towers collapsed. The Wiki article that you cite is a nice reference for this phenomena. Read it.

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x(x-y)
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Tue Oct 11, 2011 7:02 pm
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This post, promised, is meant to put forward my points for why I think the collapses of the towers WTC-1, WTC-2 and WTC-7 were not due to fire. Such a thing has never happened to structural steel skyscrapers before, yet NIST would have us believe that 3 came down in the same day vertically into their own footprint. Such an event would warrant one of the largest studies in the architectural, fire protection, structural engineering and chemical engineering industries histories'- yet vast quantities of evidence were carted away from the collapse sites as soon as possible and sent off on ships to China to be recycled:

http://911research.wtc7.net/wtc/groundzero/cleanup.html

This in itself is a crime, as shown by this law:

http://en.wikipedia.org/wiki/Spoliation_of_evidence

So, large amounts of structural steel were destroyed without being able to analyse the vast majority of it- this already seems strange due to the fact that, as stated above, not a single structural steel building has collapsed due to fire before; so, in a real scientific investigation, the evidence would've been analysed in extreme detail. This was not the case with NIST, and any attempts to defend their actions would be futile and have no credible base.

World Trade Centre Building 7

For me, WTC-7 really is the smoking gun- it is the one which made me severely doubt the official report in the first place. WTC-7 was not hit by any plane and was around 1 block away from WTC-1 and WTC-2, it sustained minor damage and had a few office fires burning away for a few hours- then, 7 hours after the collapse of WTC-1, it collapsed vertically into its own footprint in a little under 7 seconds. It was a 47 story building, structural steel built in the 1980s and so followed the construction of building codes- therefore it was sturdy and capable of sustaining a fair amount of damage without failing completely.

So, in the NIST final report of the collapse of WTC-7 they state

Quote:
WTC-7 was fully engulfed in flames


well, I think this picture pretty much disproved that ridiculous, unsupported statement:

http://www.davesweb.cnchost.com/wtc7burn.jpeg

and this one

http://imageshack.us/photo/my-images/352/wtc7cbs5nk0.gif/

And many more which a quick Google Image search would show.

Right, so you may think, what's the big deal? The fires on floors 7 and 12 as well as a few other very small fire were enough to collapse the building were they not? Well, let's look at another case study then! The 44 story, steel skyscraper Mandarin Oriental Hotel in China was a "raging inferno" over all 44 floors and yet there wasn't even a partial collapse, let alone a complete vertical collapse:

http://www.jalaybi.com/2009/02/10/wtc-size-skyscraper-building-does-not-collapse/

And another example is the "Windsor Building" in Madrid which burnt on all floors for a whole 24 hours yet it never collapsed completely, but of course WTC-7 fell completely in under 7 seconds due to fires which stretched over just 8 floors!

http://911research.wtc7.net/wtc/analysis/compare/windsor.html

So, then NIST uses the phenomenon of "thermal expansion" to try to back up their claims that WTC-7 collapsed due to fire. Thermal expansion is obviously a factor in the heating to the structural columns, however- again, the Mandarin Oriental Hotel suffered way worse fires than WTC-7 and so thermal expansion of the core columns would've been several orders of magnitude larger than the severely limited fires in WTC-7; yet it never collapsed even partially.

WTC-7 Core Columns and Structural Steel Components

As far as I know, the structural steel used in the WTC-7 building components- including the core columns- was of a carbon content of roughly 2.1%; common for structural steel. This means that the austenising temperature, the temperature at which this steel transforms to a austenite crystal structure, is 1130°C. Furthermore, the temperature at which this steel melts is in the region of 1300-1400°C; also, the "critical temperature" set by building codes for this structural steel is 800°C. What can we say of the fires in WTC-7? Well, we can definitely say that they do not reach anywhere near the austenising temperature let alone melting point (fires such as these do not burn at such temperatures). So, what about the "critical temperature" set by building code? If a normal office fire cam reach temperatures capable of causing considerable deformation of the steel columns and connections- then we have a serious problem, but then we look at the cases of the Mandarin Oriental Hotel and the Windsor Building and we can see that those extension fires did not cause significant structural deformation to the steel columns as the buildings did not collapse.

Further evidence for fires not being a major factor (or even minor) of the collapse is the evidence reported by FEMA in Appendix C of the WTC Building Performance Study- the results of the examination are striking. They reveal a phenomenon never before observed in building fires: eutectic reactions, which caused "intergranular melting capable of turning a solid steel girder into Swiss cheese." WPI provides a graphic summary of this:

Quote:
A one-inch column has been reduced to half-inch thickness. Its edges--which are curled like a paper scroll--have been thinned to almost razor sharpness. Gaping holes--some larger than a silver dollar--let light shine through a formerly solid steel flange. This Swiss cheese appearance shocked all of the fire-wise professors, who expected to see distortion and bending--but not holes.


The following are excerpts from the Appendix C of the FEMA investigation:

Quote:
Evidence of a severe high temperature corrosion attack on the steel, including oxidation and sulfidation with subsequent intergranular melting, was readily visible in the near-surface microstructure. A liquid eutectic mixture containing primarily iron, oxygen, and sulfur formed during this hot corrosion attack on the steel.
...
The thinning of the steel occurred by high temperature corrosion due to a combination of oxidation and sulfidation.
...
The unusual thinning of the member is most likely due to an attack of the steel by grain boundary penetration of sulfur forming sulfides that contain both iron and copper.
...
liquid eutectic mixture containing primarily iron, oxygen, and sulfur formed during this hot corrosion attack on the steel.
...
The severe corrosion and subsequent erosion of Samples 1 and 2 are a very unusual event. No clear explanation for the source of the sulfur has been identified. The rate of corrosion is also unknown. It is possible that this is the result of long-term heating in the ground following the collapse of the buildings. It is also possible that the phenomenon started prior to collapse and accelerated the weakening of the steel structure. A detailed study into the mechanisms of this phenomenon is needed to determine what risk, if any, is presented to existing steel structures exposed to severe and long-burning fires.


Such evidence suggests the use of thermite based explosives, not reactions of heat with the steel components (impurities are largely removed from structural steel during the formation process) as is implied by NIST but never actually proven as shown by the Appendix C quotes above- further evidence for the "official 9/11 investigation" being an unfinished and uncorroborated hypothesis.

As is documented by Steven Jones (PhD physicist, author of over 50 peer reviewed research papers), the evidence gathered by FEMA fits very well into the thermite hypothesis, as is shown again by another excerpt (applying to WTC-1 and -2 as well as -7):

Quote:
Evidence of a severe high temperature corrosion attack on the steel, including oxidation and sulfidation with subsequent intergranular melting, was readily visible in the near-surface microstructure. A liquid eutectic mixture containing primarily iron, oxygen, and sulfur formed during this hot corrosion attack on the steel.
...
The severe corrosion and subsequent erosion of Samples 1 and 2 are a very unusual event. No clear explanation for the source of the sulfur has been identified.


Right, moving onwards, this evidence so far shown here has already shown that the hypothesis of fire bringing about the total destruction of WTC-7 is extremely unlikely and does not agree with all of the observation evidence seen on the site. However, let us continue further into NIST's flawed final report. They claim that the total collapse of WTC-7 was brought on by the failure of column 79 and the connections to it- it is widely known in the architectural and structural engineering industries that the failure of one column is not enough to cause a total vertical building collapse; it is unlikely that it would even lead to any significant partial collapse. Structural steel skyscrapers are built to deal with the failure of one or more of the columns and connection, if they were not then it would be rather easy for them to collapse completely due to a terrorist setting off a small charge near to s column- by the very fact that terrorists have not targeted steel core columns suggests that even they realise that causing the failure of one column would not destroy the whole tower, and probably not even much of it all- some sagging would occur, but not collapse.

In the case of prolonged exposure to very high-temperature fires, the failure of column 79 would have been gradual and not take place instantly in a rapid connection and column deformation leading to a plastic natured collapse anyway. Such a series of events would lead to elastic deformation and a ductile failure, this goes against all observational evidence as the pictures and footage of the WTC-7 throughout the day of 9/11 do not shown any signs of progressive collapse with small failures appearing evident on the exterior of the building- no slumping or sagging of the stories was evident. So, essentially, NIST claims that the rapid failure of column 79 (which wouldn't happen due to fire) caused all of the other columns and connections to fail plastically and rapidly leading to a total collapse vertically. Many experts have stated, including Steven Barasch, Steve Dustewald, Richard Gage etc, that for the building to have fallen the way it did required the almost perfectly simultaneous failure of all of the central connections and columns of the building, the probability of a few fires stretching over 8 floors causing this to happen is virtually impossible. Let's even see how the animation provided by NIST to try to simulate the WTC-7 collapse disproves their own hypothesis as the building falls nothing like it does I'm the simulation:

Type into YouTube: "NIST Simulation Compared to Video of WTC-7 Collapse". The up-loader is "davidcarrig".

NB: NIST has never released the input data from their WTC-7 collapse simulation as they have claimed it would "jeopardise public safety". That's the biggest load of nonsense I've heard since Kent Hovind's "hypotheses".

WTC-7 Collapse Rate and Symmetry

WTC-7 collapsed completely in just under 7 seconds with a highly symmetrical collapse pattern consistent with controlled demolition. It was a 186 m tall building and so following rough calculations we can find the average velocity of collapse to be

$ \displaystyle u = \frac{s}{t} = \frac{186\,m}{7\,s} = 26.57\:m\,s^{-1}$

and then the average acceleration we can find from obtaining the final velocity, as follows

$ \displaystyle s = 1/2(u+v)t \Rightarrow v = \frac{2s}{t} - u = \frac{2(186)}{7} - 0 = 53.14\:m\,s^{-1}$

$ \displaystyle \Rightarrow a = \frac{dv}{dt} = \frac{53.14}{7} = 7.59\:m\,s^{-2}$

That gives an average acceleration of 7.59 metres per second squared as can be seen, this is roughly 77.8% of the value of g (acceleration of free fall on Earth) and is incredibly close to the acceleration of an object such as a brick being dropped from the top of WTC-7 with air resistance. This is fallacious in itself and not very impressively explained by NIST scientists whom actually have never issued an explanation as to why WTC-7 fell (during 8 stories displacement- and even they admitted this, look at their final report notes) at the rate of free fall acceleration for an object with air resistance being dropped from a 186 m height. For an object to fall at this rate means that virtually all vertical resistance was removed allowing the tower to plummet vertically- buildings don't have zero resistance of course, and on the descent what should've happened (under the conditions NIST stated the collapse takes place) would be jolts of deceleration taking place due to vertical resistance of remaining steel connections and concrete reinforced floors. Tens of thousands of tonnes of material was in the way of the vertical collapse, yet WTC-7 fell through what should've been the path of greatest resistance in a little under 7 seconds. So, the consensus among many structural engineering experts and controlled demolition experts (including Danny Jowenko who was Europe's leading controlled demolition expert, but died in car crash after he stated in a documentary that the collapse of WTC-7 "was controlled demolition, without a doubt") is that the top stories of the structure were collapsing into pre-pulverised material and matter which had been removed from the vertical path by some internal agent (such as precisely placed explosives) in order to assist in a vertical collapse.


I shall continue this in my next post, I don't want to make this one too long!

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marnixR
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Tue Oct 11, 2011 7:06 pm
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DrRocket wrote:
That does not in any way support your claim that once a piece of steel has been heated above its recrystallization temperature it does not recover to the extent that subsequently it would "collapse under its own weight".


that was not my claim

my claim was that a steel that reaches and stays for a sufficiently long time above the recrystallisation temperature will collapse under its own weight when still at or above that temperature (which it would do during a prolonged fire) - obviously this will involve buckling which then overcomes the stiffness of an I-beam, but that is a consequence not the cause of the collapse
heating steel above its recrystallisation temperature will also change its metallurgical structure, so that after having been heated to that temperature it may regain some strength on cooling, but will never regain the strength it had prior to being heated (unless you go through a repeat of the original heat treatment cycle)

oh, and btw, telling a metallurgist to read wikipedia to learn some basic metallurgical facts is like trying to teach your grannie to suck eggs - it comes across as unbearably arrogant

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DrRocket
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Tue Oct 11, 2011 10:19 pm
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marnixR wrote:
DrRocket wrote:
That does not in any way support your claim that once a piece of steel has been heated above its recrystallization temperature it does not recover to the extent that subsequently it would "collapse under its own weight".


that was not my claim

my claim was that a steel that reaches and stays for a sufficiently long time above the recrystallisation temperature will collapse under its own weight when still at or above that temperature (which it would do during a prolonged fire) - obviously this will involve buckling which then overcomes the stiffness of an I-beam, but that is a consequence not the cause of the collapse
heating steel above its recrystallisation temperature will also change its metallurgical structure, so that after having been heated to that temperature it may regain some strength on cooling, but will never regain the strength it had prior to being heated (unless you go through a repeat of the original heat treatment cycle)


marnixR wrote:
you're referring to cold strength, which is irrelevant once a metal (any metal) has exceeded its recrystallisation temperature, since it will then collapse under its own weight


Then you need to be more clear. It is quite true, and we agree that at elevated temperature steel strength and modulus degrade. You don't have recrystallize to do that.




marnixR wrote:
oh, and btw, telling a metallurgist to read wikipedia to learn some basic metallurgical facts is like trying to teach your grannie to suck eggs - it comes across as unbearably arrogant



Sorry if you were affronted, but if you get your statements right then you will not need to feel affronted. I did not recognize that you were a metallurgist. The metallurgists with whom I worked and who worked for me tended to be more accurate and precise.

There is a hell of a difference between stating that, as a material "a steel that reaches and stays for a sufficiently long time above the recrystallization temperature will collapse under its own weight when still at or above that temperature" and the collapse of a structure such as a building. One is a statement about material properties and material failure modes, while the other is a statement about applied loads to structural members resulting the failure of an overall structure -- the difference between, for instance, Von Mises failure criteria and Euler buckling of a column.

At roughly 1000F, as previously noted, common carbon steels lose about 50% of initial yield strength (dropping to 20% at 1200F), but that would hardly result in the steel, as simply a material, "collapsing under its own weight". It might well result in a buckling failure of a structure. Big difference.

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kojax
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Wed Oct 12, 2011 11:36 am
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DrRocket wrote:
At roughly 1000F, as previously noted, common carbon steels lose about 50% of initial yield strength (dropping to 20% at 1200F), but that would hardly result in the steel, as simply a material, "collapsing under its own weight". It might well result in a buckling failure of a structure. Big difference.


The idea that steel members reached that temperature is based on the assumption that all or most of the fire proofing had been displaced at the time of impact.

Going back to NIST's report:

NIST Reconstruction of the Fires in the WTC Towers. NIST NCSTAR 1-5 - E.8.4 wrote:

In the simulations, none of the columns with intact insulation reached temepratures over 300 C. Only a few isolated truss members with intact insulation were heated to temperatures over 400 C in the WTC 1 simulations and to temperatures over 500 C in the WTC 2 simulations. In WTC 1, if the firest had been allowed to continue past the time of building collapse, complete burnout would likely have occurred within a short time since the fires had already traversed around the entire floor, and most of the combustibles would already have been consumed. In WTC 2, the temperatures in the truss steel on the west side of the building (where the insulation was undamaged) would likely have continued to increase. These temperatures could have exceeded 600 C for about 15 min for large sections of the floor steel. The temepratures of the insulated exterior and core columns would not have increased to the point where they would have experienced significant loss of strength or stiffness.


The question is, how do much evidence do we really have to suggest such an overwhelming amount of the insulation would have been dislodged as we're expected to believe? Exploding plane or not, there's only so much shrapnel. It's hard to believe that bits and pieces would have hit every square inch of surface area, or even most of the square inches.

I'm just bringing this question up to see if anyone knows of some evidence to support that claim. If not, maybe it will be my next 911 research project when I have time. What is clear is that even NIST doesn't believe the building would have collapsed unless the insulation had been removed.

Another question I have on this topic: were the WTC 1&2 buildings designed purposefully to have only one mode of collapse? In the case of structure failure were they designed to always fall vertically? One thing that keeps emerging whenever I read NIST's information on the fires is that the fires were very different fires. Their distributions were different. Their heat levels were different. All they had in common is that they were caused by plane crashes. Why wouldn't we get different collapses?


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x(x-y)
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Wed Oct 12, 2011 6:39 pm
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Was my post too long for people to read on here?

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kojax
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Thu Oct 13, 2011 2:57 am
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I read through most of it, but I'm not impressed by free calculations that much. Potential energy from falling is according to the equation Mass * height * g. If the mass is considered to be proportional to the volume that means height counts twice. The energy required to destroy a building should also be more or less proportional to its volume, so in tall buildings we should expect that the ratio of energy available from the fall to energy needed to destroy them will be favorable toward energy. Once the fall starts and gains some momentum, the materials should yield like butter.

The other arguments do impress me. Let me add some things from NIST's report on building 7.

http://www.nist.gov/customcf/get_pdf.cfm?pub_id=861610

Here's what NIST has to say:

NIST Report on WTC 7, executive summary wrote:
WTC 7 was unlike the WTC towers in many respects. It was a more typical tall building in design of its structural system. It was not struck by an airplane. The fires in WTC 7 were quite different from those in the towers. Since WTC 7 was no doused with thousands of gallons of jet fuel, large areas of any floor were not ignited simultaneously. Instead, the fires in WTC 7 were similar to those that have occurred in several tall buildings where the automatic sprinklers did not function or were not present. These other buildings did not collapse, while WTC 7 succumbed to its fires.


Also:

NIST wrote:
This is the final report of the National Institute of Standards and Technology (NIST) investigation into the collapse of WTC 7, conducted under the National Construction Safety Team Act. The report is the result of an extensive, state-of-the-art reconstruction of the events that affected WTC 7 and eventually led to its collapse. Numerous facts and data were obtained, then combined with validated computer modeling to produce an account that captures the key features of what actually occurred. However, the reader should keep in mind that the building and the records kept within it were destroyed, and the remains of all the WTC buildings were disposed of before congressional action and funding was available for this Investigation to begin. As a result, there are some facts that could not be discerned and, thus, there are uncertainties in this accounting. Nonetheless, NIST was able to gather sufficient evidence and documentation to conducts a full investigation upon which to reach firm findings and recommendations.


Quote:
....
Factors contributing to the building failure were: thermal expansion occurring at temperatures hundreds of degrees below those typically considered in design practice for establishing structural fire resistance ratings, significant magnification of thermal expansion effects due to the long-span floors, which are common in office buildings in widespread use; connections that were designed to resist gravity loads, but not thermally induced lateral loads, and a structural system that was not designed to prevent fire-induced progressive collapse.


The report also mentions that the fuel lines that went to the backup generators were almost certainly not a serious contributing factor.

Quote:
Within the building were emergency electric power generators, whose fuel supply lay in and under the building. However, the fuel oil fires did not play a role in the collapse of WTC 7. The worst-case scenario associated with fires being fed by the ruptured fuel lines (a) could not have been sustained long enough, or could not have generated sufficient heat, to raise the temperature of the critical interior column to the point of significant loss of strength or stiffness, or (b) would have produced large amounts of visible smoke that would have emanated from the exhaust louvers. No such smoke discharge was observed.


I like to focus on the reports of the fires themselves because those are the most possible to recreate with confidence, and NIST did take the trouble to set up experimental test fires to compare with their predictions. We can't know the specifics of what happened to the structural components with as much certainty, so that part of the story gets a bit hazy. Though I guess in WTC 7, they were able to narrow it down to a single support beam playing the crucial role.

I'm asking myself what's more parsimonious? A fairly low temperature fire displacing that beam by expanding nearby beams in a lateral direction...... or a nano-thermite device cutting straight through it? The answer depends on what you're already predisposed to believe about everything else, really.

I wouldn't place such an action outside the reach of Mossad. They've got a super-holy outlook about things, where nothing is ever really wrong if it serves the greater good of Israel. They've done enough awful things I wouldn't be surprised if they killed 3,000 Americans too. It's also possible for simply greedy people, or "Bilderberg Group" type folks who think they're on a mission to restructure the world. Those kinds of idealists are no different from Islamic idealists. Crazy, kill happy, self justifying, & certain that history will see things their way. What I do doubt is that the government did it.


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iNow
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Wed Oct 19, 2011 1:53 pm
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I have certain thresholds on these matters, and when you see a comic from xkcd on a topic like this, I think it's time to re-examine the vigor with which you ascribe to a given mode of thought.


http://xkcd.com/966/

Image

Tooltip hover over text from the image on the page wrote:
The "controlled demolition" theory was concocted by the government to distract us. "9/11 was an inside job" was an inside job!

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x(x-y)
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Sun Oct 23, 2011 10:59 pm
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iNow wrote:
I have certain thresholds on these matters, and when you see a comic from xkcd on a topic like this, I think it's time to re-examine the vigor with which you ascribe to a given mode of thought.


I don't really see what comic has to do with the science behind the collapse of the WTC towers, besides- as I keep saying, re-investigating the collapse of the WTC towers is most certainly not a bad thing, it's science through reliability and repeatability. But, of course, anyone who questions the official story is either a "paranoid conspiracy theorist", "an ignorant troll" or an "extremist"... :roll:

It's funny though, I was always under the impression that science is all about questioning and being sceptical (albeit, not too sceptical of course)...

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iNow
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Mon Oct 24, 2011 1:49 am
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First of all, I never suggested you were a troll, ignorant, extremist, or otherwise... and I don't think that's been a very common response in this thread or others. At other sites, I've seen that happen, but I think responses here (with perhaps one or two exceptions) have been quite productive. Maybe I'm wrong, it doesn't matter though.

Yes, good science is about questioning, showing skepticism, and falsification. It's also about accepting evidence which goes against what we want to believe.

Where things breakdown a bit, though, is when the evidence is rather clear and it gets ignored anyway in favor of some... okay, I'll go ahead and say it... extreme hypothesis.

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marnixR
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Mon Oct 24, 2011 6:55 am
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the funny thing about engineering is that, under circumstances that appear to be identical, structures can behave in totally different ways - presumably through the interaction of multiple components, which can set off a different train of events depending on slightly different initial conditions
that's why engineers use safety factors in their calculations, and that's why scientific experiments may only give an indication of possible behaviour during structural collapse

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DrRocket
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Mon Oct 24, 2011 7:20 pm
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marnixR wrote:
the funny thing about engineering is that, under circumstances that appear to be identical, structures can behave in totally different ways - presumably through the interaction of multiple components, which can set off a different train of events depending on slightly different initial conditions
that's why engineers use safety factors in their calculations, and that's why scientific experiments may only give an indication of possible behaviour during structural collapse


Buckling and material failures are highly non-linear phenomena. Throw in the fact that structures have lots of unknowns --asymmetries, unknown load variations, joint strengths, geometric tolerances, defects, material variability, etc. -- and it is no surprise that the characteristics of a collapse are extremely variable.

Safety factors are intended to accomodate a wide range of uncertainties, which may or may not be realized in practice. Because of safety factors and uncertainty, calculations are usually reliable in predicting positive structural integrity, but usually significantly underestimate the loads required to initiate failure.

It is the stress/strain state immediately prior to failure, not the failure and subsequent structural response that is of interest in diagnosing the cause of a failure. Determining that state can be quite difficult, perhaps impossible, and involves sophisticated methods -- watching news films is not adequate. Evaluation of the events following the initiation of the event is of much less interest -- we know how gravity works.

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kojax
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Tue Oct 25, 2011 11:45 am
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DrRocket wrote:
marnixR wrote:
the funny thing about engineering is that, under circumstances that appear to be identical, structures can behave in totally different ways - presumably through the interaction of multiple components, which can set off a different train of events depending on slightly different initial conditions
that's why engineers use safety factors in their calculations, and that's why scientific experiments may only give an indication of possible behaviour during structural collapse


Buckling and material failures are highly non-linear phenomena. Throw in the fact that structures have lots of unknowns --asymmetries, unknown load variations, joint strengths, geometric tolerances, defects, material variability, etc. -- and it is no surprise that the characteristics of a collapse are extremely variable.



Does that make it surprising, then, that the observable characteristics of all three collapses (WTC 1,2, & 7) would be so very similar? Or is a generally vertical collapse into the building's footprint expected as the most likely outcome?

If its random, then I would think that two consecutive repetitions of the same "die roll" would be stochastically interesting.


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iNow
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Tue Oct 25, 2011 3:50 pm
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kojax wrote:
Does that make it surprising, then, that the observable characteristics of all three collapses (WTC 1,2, & 7) would be so very similar?

IMO, No. The discussion taking place here reminds me of numerology... looking for patterns on the periphery where none are needed to fit the evidence.

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DrRocket
Post  Post subject: Re: Re-investigation of 9/11 Events  |  Posted: Tue Oct 25, 2011 4:17 pm
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iNow wrote:
IMO, No. The discussion taking place here reminds me of numerology... looking for patterns on the periphery where none are needed to fit the evidence.


In some cases maybe not quite as rational as numerology.

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