Explosives Found in World Trade Center Dust

[Tone Deft]

Im a structural welder.

And I'm an architect. The way the towers fell is perfectly consistent with what one would expect, I second.

Yes, they were designed to be possibly hit by planes. And if you recall, they both stood up for a good 20 minutes after being hit- they performed as designed.

Steel, like many substances when heated, loses strength. It does not have to melt to lose this strength- it simply has to become hot enough, which is why it is always required to be protected from fire in a building. Steel is vulnerable to fire.

The structure of the WTC consisted of a series of steel tubes to either side of each window- maybe they were only about a foot in diameter, but there were many of them, a structural cage. The burning fuel took time to heat them to the point of structural failure, but once they failed- straight down. All that weight, it's thrust, just like a rocket engine in reverse. Once one floor goes, then you have the inertia which makes the rest of them pancake.

This doesn't make me throw the conspiracy theory out the window, BTW- but there is simply no logic to the statement "Jet fuel doesn't burn hot enough to melt steel". It doesn't have to. And ignore the concrete. Those buildings were held up by steel.

nice post. agreed and edjumucated. the booyman is still under the bed.

there are two trains of thought going on in this thread ATM. GRB vs MW. TD joins GL & TA in teh bomb shelter. on stage 3 is Emissary vs. the Underworld. Imaulle, Condra and the crab people are site unseen.

[Imaulle]

Imaulle-Explain how it would be different.

the floors collapsed too quickly

[Green Lemon]

Im a structural welder.

And I'm an architect. The way the towers fell is perfectly consistent with what one would expect, I second.

Yes, they were designed to be possibly hit by planes. And if you recall, they both stood up for a good 20 minutes after being hit- they performed as designed.

Steel, like many substances when heated, loses strength. It does not have to melt to lose this strength- it simply has to become hot enough, which is why it is always required to be protected from fire in a building. Steel is vulnerable to fire.

The structure of the WTC consisted of a series of steel tubes to either side of each window- maybe they were only about a foot in diameter, but there were many of them, a structural cage. The burning fuel took time to heat them to the point of structural failure, but once they failed- straight down. All that weight, it's thrust, just like a rocket engine in reverse. Once one floor goes, then you have the inertia which makes the rest of them pancake.

This doesn't make me throw the conspiracy theory out the window, BTW- but there is simply no logic to the statement "Jet fuel doesn't burn hot enough to melt steel". It doesn't have to. And ignore the concrete. Those buildings were held up by steel.

nice post. agreed and edjumucated. the booyman is still under the bed.

there are two trains of thought going on in this thread ATM. GRB vs MW. TD joins GL & TA in teh bomb shelter. on stage 3 is Emissary vs. the Underworld. Imaulle, Condra and the crab people are site unseen.

i VOTE FOR THE CRAB PEOPLE.

[Green Lemon]

That has never even happened to a building consumed by fire for days, let alone one where people are still living inside and attempting to put out the fire before it falls.

Well, actually, it happens all the time, which is why we design steel structures to be fire protected.

I know it seems a bit counter intuitive, but building fires really do get hot enough to cause steel to deform and fail. Whether you want to call it "melting" or not.

I'll stop on this point now, because if you're not gonna believe that, you're just not, but fire is a big problem for steel.

[Emissary]

Im a structural welder.

And I'm an architect. The way the towers fell is perfectly consistent with what one would expect, I second.

Yes, they were designed to be possibly hit by planes. And if you recall, they both stood up for a good 20 minutes after being hit- they performed as designed.

Steel, like many substances when heated, loses strength. It does not have to melt to lose this strength- it simply has to become hot enough, which is why it is always required to be protected from fire in a building. Steel is vulnerable to fire.

The structure of the WTC consisted of a series of steel tubes to either side of each window- maybe they were only about a foot in diameter, but there were many of them, a structural cage. The burning fuel took time to heat them to the point of structural failure, but once they failed- straight down. All that weight, it's thrust, just like a rocket engine in reverse. Once one floor goes, then you have the inertia which makes the rest of them pancake.

This doesn't make me throw the conspiracy theory out the window, BTW- but there is simply no logic to the statement "Jet fuel doesn't burn hot enough to melt steel". It doesn't have to. And ignore the concrete. Those buildings were held up by steel.

nice post. agreed and edjumucated. the booyman is still under the bed.

there are two trains of thought going on in this thread ATM. GRB vs MW. TD joins GL & TA in teh bomb shelter. on stage 3 is Emissary vs. the Underworld. Imaulle, Condra and the crab people are site unseen.

god i hate you

[Green Lemon]

Ahh the old pancake theory. You obviosuly havent noticed that Nist debunked the pancake theory themselves. Simple Physics can deduce that as each floor hit the floor underneath, the collapse would have slowed, NOT sped up.

So, you're claiming that a simultaneously burning, exploding, and collapsing skyscraper is "simple physics", and you can confidently predict the behavior of that system, from your armchair?

I am qualified to assure you that steel fails under heat, that the structural system of the building was indeed a steel exoskeleton, and that there would have been enough heat in that situation. More than that, I cannot say.

As to how, exactly, trillions of pounds of material should implode- ??? I sincerely doubt that you have any more an idea than me, thus you can only choose which expert opinion to hue to. Fair enough.

What I find most worrying is the apparent collapse of building 7.

[UKRuss]

This is the best thread ever.

Although i think this thread in itself is a conspiracy...of some sort....for what purpose I know not. But you can feel it in the construction. sinister.



I just LOVE the US of A! You are all as mad as cheese!

[Green Lemon]

THat's me! Mad as cheese!

(WTF does that mean?)

[UKRuss]

acceptance and denial. You are already half way there.

Mad as a bag of cats.

[Emissary]

Ahh the old pancake theory. You obviosuly havent noticed that Nist debunked the pancake theory themselves. Simple Physics can deduce that as each floor hit the floor underneath, the collapse would have slowed, NOT sped up.

So, you're claiming that a simultaneously burning, exploding, and collapsing skyscraper is "simple physics", and you can confidently predict the behavior of that system, from your armchair?

I am qualified to assure you that steel fails under heat, that the structural system of the building was indeed a steel exoskeleton, and that there would have been enough heat in that situation. More than that, I cannot say.

As to how, exactly, trillions of pounds of material should implode- ??? I sincerely doubt that you have any more an idea than me, thus you can only choose which expert opinion to hue to. Fair enough.

What I find most worrying is the apparent collapse of building 7.

The idea of path of least resistance is a simple idea yes. You can do a simple home experiment with some twigs tied together and placed vertically and drop a rock on them, the rock will bounce off, unless its a huge rock in which case the twigs will bend. No way on this earth things collapse into each other, doesnt happen, find one observable time its happened. The only way this could have happened is if the collapse initiated from the bottom or simultaneously to all load bearing sections.

And dont bring this crap about armchair scientist into things (its does your obvious intellect no good). I have been reading and researching the WTC for the past 6 years. I've gone through times when i wasn't sure which theory was true, but science won out in the end.

If your qualified to know that steel fails under heat, then your obviously qualified to realise that as it bends and contorts it actually strengthens no? Once again though it is a moot point as the fire was going out, and thus the steel would have been cooling at the time of collapse, not heating up. Another hole in your theory about steel melting would be the fact that molten metal was found in the rubble of the WTC which stayed hot for weeks and could be seen on satelite imagery. A fire from jet fuel Cant heat metal to that level. Only thermite can. And anyway The world trade centers were designed to take THREE impacts to any part of the building and still remain standing . The exoskeleton was like a screen door, you could puncture it anywhere as much as you like and it would have no effect. Only severing of the core columns could initiate collapse. And if the plane had severed them on impact the building would have collapsed un uniformly a few seconds after impact.

If you want to get into a debate about the actual science of the collapse i suggest you read the multitude of scientific peer reviewed papers on the subject by architects physicist and engineers before we begin. The Only people who believe the nist report are the people who wrote it and the people too lazy to go through the arduous task of researching REAL science.

The towers were brought down by controlled demolition, the evidence is so stupefyingly obvious we didnt even need to find out that suprise suprise there was thermite in the WTC dust. Its just another weight that is tipping the scale and flipping the lies off the other side.

[Emissary]

That has never even happened to a building consumed by fire for days, let alone one where people are still living inside and attempting to put out the fire before it falls.

Well, actually, it happens all the time, which is why we design steel structures to be fire protected.

I know it seems a bit counter intuitive, but building fires really do get hot enough to cause steel to deform and fail. Whether you want to call it "melting" or not.

I'll stop on this point now, because if you're not gonna believe that, you're just not, but fire is a big problem for steel.

So you are really suggesting and open air fire, with black smoke (low heat) can "melt" steel. Why the hell do we need to smelt things, just pop it over a campfire and leave it for a few hours. Can you explain to me why my cooking stove grill doesn't melt which has a far higher temperature applied to it than anything seen in the WTC fires.

And while we are at it, why dont we do away with controlled demolition teams. Its pretty obvious we dont need them. The first 3 steel structures in the history of mankind to collapse due to fire, all collapsed into their own footprints. Seems like we can do away with the pseudo science of controlled demos and again just light a few fires around the building and wait a few hours for a perfect collapse.

[sporkles]

[Green Lemon]

Your stove does get hot enough to make the steel glow red, Emissary, (at least mine does) and that is the point at which steel loses strength- and no, it does not gain strength as it bends and contorts, it simply buckles- where on earth did you get that idea?

Wikipedia:

Fireproofing of structural steel

...Structural steel requires external insulation (fireproofing) in order to prevent the steel from weakening in the event of a fire. When heated, steel expands and softens, eventually losing its structural integrity....

Anyway, I said I'd stop, but this is such a basic point I have trouble reading it. Another internet construction source :
(from http://www.azobuild.com/details.asp?ArticleID=3621)

Reasons for fire damage

All materials weaken with increasing temperature and steel is no exception. Strength loss for steel is generally accepted to begin at about 300ºC and increases rapidly after 400ºC, by 550ºC steel retains about 60% of its room temperature yield strength. This is usually considered to be the failure temperature for structural steel. However, in practice this is a very conservative assumption; low loads, the insulating effects of concrete slabs, the restraining effects of connections etc. mean that real failure temperatures can be as high as 750ºC or even higher for partially exposed members.

Like I said, I am not arguing against the tinfoil hat crowd- I'm with Condra and the crab people myself. There could very well have been thermal detonators strategically placed around each column, I have no idea. I wouldn't put it past him. But I do know 2 things: 1) steel fails under heat 2) it is very difficult to predict how large, complex structural systems will fail under real world conditions- even for the pros (of which I am one).

Anyway, always nice chatting with you E, and I'll try and have a look at those links a bit later- its certainly a subject I have not investigated to its fullest.

We have had pictures of the unsinkable Titanic, I leave you all with a pick of one of the worlds first fireproof steel buildings:

http://www.newyorkshitty.com/wp-content ... esmall.jpg

...and pretty please, stop saying we've never had any steel buildings collapse because of fire...its just wrong.

[mikemc]

Right, right: the steel beams would not need to liquify, melt, to lose integrity. If they deformed, "wilted", they would. But the fact that the building would fall unpredictably is a good argument for bringing it down in a controlled manner.

After the decades ago truck bomb attack, if there was an expectation that the buildings would be attacked again, maybe in a different way, maybe in the same way, the question would be "how can the worst case be mitigated?".

My theory is based on this evidence that explosive traces were found. ThrowAway's earlier question, the thing that makes me think explosives were used was the OP's indication that traces of them had been found, the way the buildings came down, little pieces 'popping' out well below the initial damage, and the way that WTC 7 came down plus that not really well explained statement by the complex's business owner regarding "pulling" the WTC 7 building.

[edit] and, yeh, there is the whole "that and four dollars will buy you a bag of hot nuts from an NYC street vendor" . But I would be happy to see various models taking into account the 'wilting' of the beams that would show how the buildings would fall under those conditions. My thought is that the top above the impact damage would twist and fall to the side, If the torque from that twisting is enough to cause the rest of the 'unlwilted' steel core to twist as well, pulling out the rivets and joints holding it together, then that could cause little things pop out way down below the initial damage, and explains those. [edit edit] If the twisting is enough to cause damage all the way through the steel core, causing all the joints to become disconnected, then transferring almost all of the building's weight to the "tube cage" which then buckles, then maybe that's all it takes.

Still doesn't explain WTC7 which was constructed differently.

[Emissary]

Oh ok, right i remember reading somewhere (i cant find the info sorry) that as melted iron is compacted vertically (as would have been the case in a gravity driven collapse), it would have become stronger. Obviously i am mistaken. But Unknowingly you have just once again corroborated the science behind the collapse. You state that the Iron Buckled yes? Althought Nist would not agree with you. In which case the Collpase would have followed the path of least resitance. Which means an un uniform collapse. You seem to have come up with your own theory on how the towers collapsed which agrees with neither Nist nor the CT. Being an architecht could you please explain thermal expansion to a layman (and not from the wiki article) but from what you learnt from 5-6 years of University studying your subject.

Yep my stove does get red hot, and even if i put a giant bowl of water on it , it still holds it together perfectly fine. The fires would have had to have been over 300c for the iron to have even begin to weaken and would have to have reached 600c for any kind of dangerous weakening. Many physicsts have done investigation into this and say that there is no physical way the temperature anywhere in the building could have exceed 257c from the burning of jet fuel and general office furniture (overestimated)

Also i dont understand your picture? that building is still standing. Please post us in the direction of other steel buildings that have suffered total collapse into their own footprints. Thanks.