The truth about 911

[marvenger]

Re: The truth about 911

I found this transcript of an interview between leslie roberston, supposed chief engineer of the world trade center a claim seriously questioned in the piece, and steven jones a recently retired professor of pysics. The interview was on KGNU radio, denver october 26 2006.

The interview is annotated by greg roberts editor of 911 research who has obviously done a lot of research into this. I'm sure some evidence of bias in greg's commentry can be found but on the whole I think his problems with the interview are mostly valid and cast significant doubt about the quality of the investigation into the collapses of the towers. A great read.

[tombat1913]

Re: The truth about 911

Plus the NIST report is public. All legitimate scientists in the world who work in the field of structural failure are probably examining it word by word and digit by digit. If it's a fabrication how long do you think it will take until the fraud or bad science is spotted?

IT HAS BEEN SPOTTED! It's the whole reason this posts exists in the first place, it's the reason AE911Truth exists, and Pilots for 911 Truth, and Veterans for 911 Truth, and the list goes on and on. You folks keep saying "something so big is impossible to cover up, so why hasn't the truth come out?" Then when it's presented to you, you say "well why hasn't the truth come out, I mean this type of thing is just too big to cover up."

[marvenger]

Re: The truth about 911

it's beacuse people have internalised views of how the world works(me included). I think it was in the Russia vs West thread where i've heard $#* say that the russians are basically automatically to be assumed to occupy the morally inferior position in the georgian conflict because they blew up buildings in moscow and blamed it on the chechnyan's. So obviously to suddenly start thinking 911 was an inside job is going to be a massive change to how he percieves the moral virtue in the world and he will do a lot, or little in objectively looking at facts, to avoid changing that view.

[c1ue]

Re: The truth about 911

just using my imagination here. If the weight of the building is 1/5 steel then by analogy you could imagine one hollow steel support 70 stories tall, then imagine 5 30 story hollow supports bolted together side by side hovering two stories directly above the 70 story support. Then let the 30 story supports fall. What i can't imagine is the 70 story support liquifying into droplets and offering absolutely no resistance when its hit by the 30 story supports.

Uh, because you're not thinking this through.

Let's start with defining the units: 1 joule = 1 newton * 1 meter = 1 kg at 1 meter height on a world with gravity 1 m/sq. second. Potential energy from Earth gravity = mass (kg) * gravity (9.8m/sq.s) * h (meters)

The WTC buildings with approx. 200 steel columns of 14" square plates had total cross section of steel supports is: 39200 square inches = 25.29 square meters.

The support columns strength was something between 36 and 100 Ksi = 36000 to 100000 pounds per square inch. For the entire building at rest it would be fine: 50K psi * 39200 square inches / 2000 lbs/ton = 980000 tons = or roughly 50% margin vs. the 500K ton actual weight.

In the case of the falling top 1/3 of the WTC, the entire 70 story support does not equally distribute the shock of the 30 stories striking it. There is some distribution, but transmission of force throughout the support would not be equal, and the force in question would be according to Newton.

Assuming said top 1/3 portion weighed 100,000 tons = 90.9M kg, thus the 30 floors would have at least 890 million joules of potential energy converted into kinetic energy (height of 1 meter only), and probably at least 10 times that (assume average fall height of 50 meters and 2 to 1 weight differential between top of WTC and 70th floor.

1 ton of TNT is 4 billion Js, so the energy of said floors falling is something like 2 tons of TNT.

With the kinetic energy of the falling mass from above being 9 billion J, the question is how much energy can the steel absorb.

From http://books.google.com/books?id=IBb...um=3&ct=result

Mild steel can absorb 10000 J/kg. Presumably stronger steel can absorb more. Let's say 5x more.

But the entire structure of steel doesn't evenly spread the energy applied; when a can is bent for example, it is only in the seams that actual energy winds up being applied - and these seams are millimeters in size.

Thus the 9 billion joules could deform somewhere around 180000 kg of steel, more than enough to pop a seam somewhere along the remaining 700 feet of columns, with ensuing collapse taking care of any remaining portion. Or perhaps the 9 billion joules popped the seams between beams; the supports were prefabbed to around 2 or 3 floors worth and the overall collapse was a vertical domino effect.

The final conversion of kinetic energy into heat would not have to happen until the whole mass came to a stop at the bottom - after all, the initial collapse just unchains the still standing structure (and its potential gravity energy) into additional kinetic energy.

For the entire structure - 500K tons with an average height of 150 meters, we're talking 660+ billion J = 150 tons of TNT ... that's a lot of energy.

[Spartacus]

Mod The Parent Up !!!!

too bad the iTulip software doesn't let us to do that

[Guest]

Re: The truth about 911

Phirang -

Surprised to read you venturing into such conjectures.

A good exercise: create a conspiracy investing "bot," who allocates his resources according to the principle that he'd second-guess the "illuminati". This would be a very interesting experiment, and defining what benefits the "illuminati" could provide insight.

[EJ]

Re: The truth about 911

Rant and rave is usually short and sweat threads of jokes, political rants, and other fun. I'm quite surprised by this thread. I'd have thought iTulipers would know better.

Each trade tower weighed approximately 500,000 tons. When flames from the aircraft finally melted enough supports, the top 1/4 to 1/3 of each building, weighing 125,000 tons to 150,000 tons, fell 12 feet, the height of one floor, at 32ft/sec/sec, hitting the floor below with more force (F = M*A) than the next floor could support, or the next, or the next, as force increased with velocity and mass with the collapse of each floor. Terminal velocity was quickly reached.

The 500,000 ton building had too much inertia to fall in any direction other than straight down. Imagine the size of the force that would be needed to move it in a lateral direction.

For more, read here. I'm asking Fred to close this thread.

[Jim Nickerson]

Re: The truth about 911

[quote=EJ;44934]Rant and rave is usually short and sweat threads of jokes, political rants, and other fun. I'm quite surprised by this thread. I'd have thought iTulipers would know better.

Each trade tower weighed approximately 500,000 tons. When flames from the aircraft finally melted enough supports, the top 1/4 to 1/3 of each building, weighing 125,000 tons to 150,000 tons, fell 12 feet, the height of one floor, at 33ft/sec/sec, hitting the floor below with more force (F = M*A) than the next floor could support, or the next, or the next, as force increased with velocity and mass with the collapse of each floor. Terminal velocity was quickly reached.

The 500,000 ton building had too much inertia to fall in any direction other than straight down. Imagine the size of the force that would be needed to move it in a lateral direction.

For more, read here. I'm asking Fred to close this thread.[/quote]

Awh, shit, I was sure there would within the millenium turn up some opportunity to make money out of this.

[Spartacus]

Re: The truth about 911

a knight is about to hit Eric with a rubber chicken

Rant and rave is usually short and sweat threads of jokes

We were not expecting the Spanish Inquisition, Eric.

(reply: no one expects the Spanish Inquisition(TM) !!! .... I think you know the rest)

[tombat1913]

Re: The truth about 911

I'd have thought iTulipers would know better.

I must have misinterpreted "The one forum on iTulip where you can let it all out", my apologies. Marvenger and Rajiv please keep up the good work (elsewhere).

[marvenger]

Re: The truth about 911

Thanks for your contribution EJ.

Have to add to it before this thread closes however.

From the article you referenced

The World Trade Center was not defectively designed. No designer of the WTC anticipated, nor should have anticipated, a 90,000 L Molotov cocktail on one of the building floors.

Following the B-25 bomber impact into the empire state building in ww2, which withstood the impact, John skilling the lead engineer of the wtc built the building to be able to withstand a fully fuel loaded 707 impact at cruising speed of 600mph. 25% of strucural supports were designed to be able to fail, max of 15% failed on 911. The collumns were overbuilt by a factor of 20, so they could take the excess load.


Also from the article you referenced

The perimeter tube design of the WTC was highly redundant. It survived the loss of several exterior columns due to aircraft impact, but the ensuing fire led to other steel failures. Many structural engineers believe that the weak points—the limiting factors on design allowables—were the angle clips that held the floor joists between the columns on the perimeter wall and the core structure (see Figure 5). With a 700 Pa floor design allowable, each floor should have been able to support approximately 1,300 t beyond its own weight. The total weight of each tower was about 500,000 t.

As the joists on one or two of the most heavily burned floors gave way and the outer box columns began to bow outward, the floors above them also fell. The floor below (with its 1,300 t design capacity) could not support the roughly 45,000 t of ten floors (or more) above crashing down on these angle clips. This started the domino effect that caused the buildings to collapse within ten seconds, hitting bottom with an estimated speed of 200 km per hour.


But from wikipedia

The Federal Emergency Management Agency (FEMA) completed its performance study of the buildings in May 2002. It declared the WTC design sound and attributed the collapses wholly to extraordinary factors beyond the control of the builders. While calling for further study, FEMA suggested that the collapses were probably initiated by weakening of the floor joists by the fires that resulted from the aircraft impacts. According to FEMA's report – and subsequently contradicted by NIST's findings – the floors detached from the main structure of the building and fell onto each other, initiating a progressive "pancake" collapse. ^[3]
FEMA's proposed explanation was rejected by a later, more detailed investigation by the National Institute of Standards and Technology (NIST), which was completed in September 2005. Like FEMA, NIST vindicated the design of the WTC, noting that the severity of the attacks and the magnitude of the destruction was beyond anything experienced in U.S. cities in the past. NIST also emphasized the role of the fires, but it did not attribute the collapses to failing floor joists. Instead, NIST found that sagging floors pulled inward on the perimeter columns: "This led to the inward bowing of the perimeter columns and failure of the south face of WTC 1 and the east face of WTC 2, initiating the collapse of each of the towers."<sup>[4]



Obviously still a lot of questions to be answered. It's a pity far less money was spent on investigating clinton's blow job than was spent on investigating 911.</sup>

[Rajiv]

Re: The truth about 911

Obviously still a lot of questions to be answered. It's a pity far less money was spent on investigating clinton's blow job than was spent on investigating 911.

far more money you mean

[tombat1913]

Re: The truth about 911

The World Trade Center was not defectively designed. No designer of the WTC anticipated, nor should have anticipated, a 90,000 L Molotov cocktail on one of the building floors.

Incorrect, a commercial jet impact WAS part of the design specification, and UL signed off on it! This is from the mouth of one of the designers, not speculation.

[FRED]

Re: The truth about 911

I must have misinterpreted "The one forum on iTulip where you can let it all out", my apologies. Marvenger and Rajiv please keep up the good work (elsewhere).

Letting it all out is one thing, 50 posts to a thread on 9/11 says to anyone of the 1000s of guests who come here that more than a couple iTulipers had a window seat in high school physics class. Airplane full of fuel, melted supports, and F = V * M. Case closed.