What it wasnt.

The offical story as to why the WTCs collapsed is:

1. The airplane impact with damage to the columns.
2. The ensuing fire with loss of steel strength and distortion.

Ok. Break it down.

1. The airplane impact with damage to the columns.

The early news reports noted how well the towers withstood the initial impact of the aircraft; however, when one recognizes that the buildings had more than 1,000 times the mass of the aircraft and had been designed to resist steady wind loads of 30 times the weight of the aircraft, this ability to withstand the initial impact is hardly surprising. Furthermore, since there was no significant wind on September 11, the outer perimeter columns were only stressed before the impact to around 1/3 of their 200 MPa design allowable.

The only individual metal component of the aircraft that is comparable in strength to the box perimeter columns of the WTC is the keel beam at the bottom of the aircraft fuselage. While the aircraft impact undoubtedly destroyed several columns in the WTC perimeter wall, the number of columns lost on the initial impact was not large and the loads were shifted to remaining columns in this highly redundant structure. Of equal or even greater significance during this initial impact was the explosion when 90,000 L gallons of jet fuel, comprising nearly 1/3 of the aircraft’s weight, ignited. The ensuing fire was clearly the principal cause of the collapse. Not the impact of the plane.
Link

Can we all agree that it wasnt the impact of plane that caused the collapse? Everyone stop, think it over... Read it again. It had to be the fire right?

2. The ensuing fire with loss of steel strength and distortion.

Temperature is defined as an intensive property, meaning that it does not vary with the quantity of material, while the heat is an extensive property, which does vary with the amount of material. One way to distinguish the two is to note that if a second log is added to the fireplace, the temperature does not double; it stays roughly the same, but the size of the fire or the length of time the fire burns, or a combination of the two, doubles. Thus, the fact that there were 90,000 L of jet fuel on a few floors of the WTC does not mean that this was an unusually hot fire. The temperature of the fire at the WTC was not unusual, and it was most definitely not capable of melting steel.Link

FACT
The maximum temperature of hydrocarbon fires (jet fuel) burning in pure oxygen is 3,200°C.

FACT
The maximum temperature of hydrocarbon fires (jet fuel) burning in the atmosphere without pressurization or pre-heating is 825ºC.

FACT
The melting point of typical structural steel is 1510ºC .

It was impossible for the plane crash and the jet fuel to bring down the towers. SCIENTIFICALLY IMPOSSIBLE

Then what did? I dont know. All I know is what it wasnt.



[edit on 30-3-2006 by Tasketo]

You appear to have not read the whole web page you linked to, it appears you have plucked quotes from it and ignored the other parts that contradict your own findings.
Don't worry though, that appears to be a common problem that the "truth movement" has, so you should fit in well with them.




If you had you would have read the conclusion that they came to.

Thus, the failure of the steel was due to two factors: loss of strength due to the temperature of the fire, and loss of structural integrity due to distortion of the steel from the non-uniform temperatures in the fire.

While it was impossible for the fuel-rich, diffuse-flame fire to burn at a temperature high enough to melt the steel, its quick ignition and intense heat caused the steel to lose at least half its strength and to deform, causing buckling or crippling. This weakening and deformation caused a few floors to fall, while the weight of the stories above them crushed the floors below, initiating a domino collapse.

The piece does not say that the steel melted.

It is known that structural steel begins to soften around 425°C and loses about half of its strength at 650°C.4 This is why steel is stress relieved in this temperature range. But even a 50% loss of strength is still insufficient, by itself, to explain the WTC collapse. It was noted above that the wind load controlled the design allowables. The WTC, on this low-wind day, was likely not stressed more than a third of the design allowable, which is roughly one-fifth of the yield strength of the steel. Even with its strength halved, the steel could still support two to three times the stresses imposed by a 650°C fire.

The additional problem was distortion of the steel in the fire. The temperature of the fire was not uniform everywhere, and the temperature on the outside of the box columns was clearly lower than on the side facing the fire. The temperature along the 18 m long joists was certainly not uniform. Given the thermal expansion of steel, a 150°C temperature difference from one location to another will produce yield-level residual stresses. This produced distortions in the slender structural steel, which resulted in buckling failures. Thus, the failure of the steel was due to two factors: loss of strength due to the temperature of the fire, and loss of structural integrity due to distortion of the steel from the non-uniform temperatures in the fire.

[edit on 30-3-2006 by Stateofgrace]

ok... Not to pick and choose but the paragraph right above that says

It is known that structural steel begins to soften around 425°C and loses about half of its strength at 650°C.4 This is why steel is stress relieved in this temperature range. But even a 50% loss of strength is still insufficient, by itself, to explain the WTC collapse. It was noted above that the wind load controlled the design allowables. The WTC, on this low-wind day, was likely not stressed more than a third of the design allowable, which is roughly one-fifth of the yield strength of the steel. Even with its strength halved, the steel could still support two to three times the stresses imposed by a 650°C fire.

Now the on;y question is would the impact of the plane have done the rest? With little doubt the answer is a solid no

Its a no because the plane hit before the fire damage. The impact of the plane didnt cause the collapse. Nor did the fire.

And if you have noticed, the building that fell first was the building that was hit second. And most of its jet fuel exploded outside the building. And on top of that, it hit the building on its corner, structural damage was minimum.


[edit on 30-3-2006 by Tasketo]

[edit on 30-3-2006 by Tasketo]

ok... Not to pick and choose but the paragraph right above that says

Which is why the following paragraph starts with.....

The additional problem was distortion of the steel in the fire. Then goes on to explain how that works.

Tada....

problem solved.

Of course you might have noticed that if you weren't trying to select only facts that support your theory.

Thus, the failure of the steel was due to two factors: loss of strength due to the temperature of the fire, and loss of structural integrity due to distortion of the steel from the non-uniform temperatures in the fire.

What part of this summerisation don't you understand ?

Look. I dont care what the web page says.

The offical story is that the steel melted and that was what caused the "pancake domino effect"

If the steel didnt melt, if it wasnt weakend enough for it to collapse, if the plane didnt bring it down on impact then what did?

Even if it some how did, it wouldnt have fallen in near free fall speed that looked like a demolition job.

[edit on 30-3-2006 by Tasketo]

Look. I dont care what the web page says.

So why are you trying to selectively use them as supporting evidence?

But, thanks for pointing out your frame of mind, keep up with the selective use of info.

The offical story is that the steel melted and that was what caused the "pancake domino effect"

Could you point me to where it says the buildings fell due to steel melting?

[edit on 30/3/06 by Skibum]

Now the on;y question is would the impact of the plane have done the rest? With little doubt the answer is a solid no

Its a no because the plane hit before the fire damage. The impact of the plane didnt cause the collapse. Nor did the fire.

And if you have noticed, the building that fell first was the building that was hit second. And most of its jet fuel exploded outside the building. And on top of that, it hit the building on its corner, structural damage was minimum.

I see why you would think so, unfortunately, there is a point missing here.

The structure to the two towers is built as an exoskeleton system. Their frames ARE the walls. The fire raging at the point of impact would have the added effect of both the impact and the fire.

Most buildings are built with a central core. Usually done that way to make construction more feasable, and to give the most strength to the elevator shafts to ensure they stay straight and without shifting. That, and its become common practice to build with a strong center.

The two towers were different. You are correct in saying that most of the fuel exploded on the outside of the building... but the outside of the building was in fact the structure of the building.

If you ask me, building a structure with an exoskeleton is retarted... interesting to study, but extremely inefficient.

FACT 1

A group of determined dedicated terrorists decided to hijack a number of planes.

FACT 2

The flew said planes into certain buildings in the USA designed to cause maximum damage - and Im sad to say disbelief

FACT 3

That country's minds will spend the following 5 years following Alice through the looking glass - providing repetition of the very actions that caused the initial effect in the first place. In the words of a famous ad - DENIAL is not a only a river in Egypt. If you want to sort a problem sort the root - your own self denial of what happened - god sake you woke up up after Pearl Harbour - now get with the programme. Hey Im not even American - you guys cut us lose years ago - but get behind the guys whoo are fighting for your basic rights - the right to post here for a start.

OK rant off I will go back to my UK bunker and watch the big guys throw rocks at each other.

Look. I dont care what the web page says.

You posted the link and invited debate, sorry if I entered with a differing view and actually took the time to read the link you posted and agree with what is being put forward in the link you posted.

Incidently neither the FEMA or the NIST reports states that steel melted, but were weakend by the damaged caused by the planes and the resultant fire, which is about the only thing you got right,. The fire was not strong enough to melt steel, it weaked it to the point of catastrophic failure.

As supported in your link. Tata.

[edit on 30-3-2006 by Stateofgrace]

[edit on 30-3-2006 by Stateofgrace]

You can attack the web page all you want, but you cant deny facts.

The building fell at nearly free fall speed. If fire and impact damage is what made it fall, that would have not happend because its impossible.

Even if fire did bring it down, it shoud have only partially fallen into its self and not have been completey destroyed and fall at near free fall speed. The entire building wasnt damaged by fire so how did it fall so quickly and so completely?

The building would have supported itself during the collapse and it would have stopped.


WHY IS EVERYONE IGNORING THE FACT THAT IT FELL AT NEARLY FREE FALL SPEED?


[edit on 30-3-2006 by Tasketo]

[edit on 30-3-2006 by Tasketo]

Incidently neither the FEMA or the NIST reports states that steel melted,

Are you sure? The "truth movement" says it does, I think its one of the pillars of their arguement.

If not, I'll have to add that to the list of "truths" that the "truth movement" bandies about.

9 feet of reinforced concrete...check
melting steel... check


Not a complete list, just the ones I've dealt with today.

You can attack the web page all you want, but you cant deny facts.

Who is attacking the web page? I think most of the posters in this thread are in at least substantial agreement with it. We are attacking your selective use of the info contained on the web page, but not the page itself.

The building fell at nearly free fall speed.

Got proof?

that would have not happend because its impossible.

Impossible, you say! I'm really gonna need hard evidence of that.

it shoud have only partially fallen into its self

some evidence would be nice to back up this claim, have you run computer simulations or are you just going on the word of some of the members of the "truth movement"?

WHY IS EVERYONE IGNORING THE FACT THAT IT FELL AT NEARLY FREE FALL SPEED?

Honestly, I don't see it as an issue, it's IMO just another smoke and mirrors show sponsored by the "truth movement".
"oh look they fell at nearly freefall speed, gotta be controlled demo"

Whoop-de-doo.

Besides, if you want this thread to be about free falling buildings there are a few active threads already going on that topic.


try this one on for size....
www.abovetopsecret.com...


[edit on 30/3/06 by Skibum]

I dont care what anyone says. FEMA, truth movement what ever. Dont care. Dont bring them in this. Just look at the facts.

The building fell at a speed as if it were falling through air.

It fell at nearly free fall speed. I dont know how many times I can say this. It would have been impossible for it to fall straight down at that speed. The lower building would have resisted. Not fall is if it was falling through air.

It fell at nearly free fall speed. how can it do that when it fell into its self? Its impossible. It dosent matter what fema says. Science dosent lie.

Whenever one body exerts force upon a second body, the second body exerts an equal and opposite force upon the first body.

www.school-for-champions.com...

One example of this law is if you push against a door with a certain force, the door is also pushing with the same force against you.

www.school-for-champions.com...

Newton's Laws of Motion wernt woking on 9/11? The fall itself is proof it wasnt a plane or fires that brung it down.

[edit on 30-3-2006 by Tasketo]

I dont care what anyone says.

I guess that pretty much sums it up then, no use in having any sort of conversation with you.

My those sure are some pretty big blinders you're wearing, do they come in 2xl?

Science dosent lie.

So when are you going to post the mathematical proof it was impossible, certainly someone as well studied as yourself should be able to tell us exactly how fast as well as how they should have fallen.

BTW as in school, you are expected to show your work so we can see exactly how you came to your answer.

Until you provide such proof, you are only stating your opinion.

[edit on 30/3/06 by Skibum]

Come now Skibum, do you honestly not question the official line in any manner?

I've have watched numerous documentaries voicing a large array of footage and audio broadcasts most of them asking the same questions.

There are numerous questions that are asked and can be answered very simply, but the manner in which the 2 towers collapsed and the later collapse/pulling of building 7, spew a multitude of questions that remain unanswered.

Skibum

You quote half of what I say and then try to spin it into something else.

This is what I hate. You have nothing to say about Newton's Laws of Motion so you try to spin what I say and then go off topic.

If you dont have anytging to say about the subject of this topic, please dont post. And please dont try to spin what I say.

Come now Skibum, do you honestly not question the official line in any manner?

Sure, I do.

I've have watched numerous documentaries voicing a large array of footage and audio broadcasts most of them asking the same questions.

I've watched them too, I obviously don't agree with their claims though.

There are numerous questions that are asked and can be answered very simply, but the manner in which the 2 towers collapsed and the later collapse/pulling of building 7, spew a multitude of questions that remain unanswered.

Of course there will be a multitude of questions, its a complex problem with many variables. Some of those questions can only be answered by speculation.

Originally posted by Skibum

Incidently neither the FEMA or the NIST reports states that steel melted,

Are you sure? The "truth movement" says it does, I think its one of the pillars of their arguement.

www.physics.byu.edu...

"The government reports admit that the building fires were insufficient to melt steel beams -- then where did the molten metal come from? Metals expert Dr. Frank Gayle (working with NIST) stated:

Your gut reaction would be the jet fuel is what made the fire so very intense, a lot of people figured that's what melted the steel. Indeed it did not, the steel did not melt"


NIST determined that there was no evidence that any of the samples had reached temperatures above 600 ºC. (NIST, 2005, pp. 176-177; emphasis added.)

At any given location, the duration of [air, not steel] temperatures near 1,000oC was about 15 min to 20 min. The rest of the time, the calculated temperatures were near 500oC or below.” (NIST, 2005, p. 127, emphasis added.)

NIST contracted with Underwriters Laboratories, Inc. to conduct tests to obtain information on the fire endurance of trusses like those in the WTC towers… All four test specimens sustained the maximum design load for approximately 2 hours without collapsing.” (NIST, 2005, p. 140, emphasis added.)

Nor does NIST (or FEMA or the 9-11 Commission) even mention the molten metals found in the basements of all three buildings (WTC 1, 2 and 7).

These are from Prof Jones own theary quoting NIST. I'll find the exact chapter from the FEMA and Nist reports later but it kind of late for me just now.


From my understanding of these guys ( the schollars for truth) are adderment that the temperatures did not reach anywhere near the melting point of steel and from the source above I have tried to point out specific referances to such.
This is from Prof. Jones and it was these claims that led me to look at FEMA and NIST.

Even Prof Jones admits that the fires were not hot enough to melt the steel even though the article is called "Molten metal, flowing and in pools, on 9/11/2001"

ehmmm must have been some else..........maybe loss of strenght.