Fire Could Easily Have Been Cause of WTC Collapse

I have read several threads that say that the jet fuel fires could not have caused the collapse of the WTC Towers because they couldn't generate enough heat to cause the steel structure to fail. I know that the heat required to reduce the strength of steel to the point of failure is far less than what is needed to melt it.

The attached link shows a bridge after a gasoline fire. There are pictures showing one of the main I-beams twisted like a noodle. Notice that this bridge is an open structure and there is nowhere for the heat to build up. Notice that the I-beam shown is several times larger than the ones used in the WTC.

Burned Bridge

The bridge is still standing....It did not collapse and eject pieces of itself 100's of feet or pulverize itself like the WTC towers did. Now if the bridge collapsed and ejected pieces 100's of feet and was pulverized then Id say this was a good find.

Originally posted by etshrtslr
The bridge is still standing....It did not collapse and eject pieces of itself 100's of feet or pulverize itself like the WTC towers did. Now if the bridge collapsed and ejected pieces 100's of feet and was pulverized then Id say this was a good find.

The bridge also wasn't 1000 ft tall and didn't have to support anywhere near the load that the the WTC Tower's structure had to. The I-beam of the bridge completely lost it's structural integrety and it's ability to carry any type of load. Look at a Physics book under the term Kinetic Energy. Your ejections and pulvirization happened as a result of the failure of the Tower's steel structure because of the heat of the fire. The Kinetic Energy of the tower's structure above the failure point did the rest.

[edit on 7-11-2006 by JIMC5499]

The bridge also wasn't 1000 ft tall and didn't have to support anywhere near the lost that the the WTC Tower's structure had to. The I-beam of the bridge completely lost it's structural integrety and it's ability to carry any type of load.

It should all be realitive....the whole length and breadth of the bridge burned....That in noway happened at the WTC towers.....at most the upper third of the buildings burned for less than one hour......the middle third and lower third should have been able to support the upper third of the building.

Originally posted by JIMC5499
The bridge also wasn't 1000 ft tall and didn't have to support anywhere near the lost that the the WTC Tower's structure had to. The I-beam of the bridge completely lost it's structural integrety and it's ability to carry any type of load. Look at a Physics book under the term Kinetic Energy. Your ejections and pulvirization happened as a result of the failure of the Tower's steel structure because of the heat of the fire. The Kinetic Energy of the tower's structure above the failure point did the rest.

Bolded by me. This sentence is wrong. The I-beam sagged. It did not lose structural integrity. It did not completely disintegrate upon itself. And as stated before, it did not eject itself.

Furthermore, I have no idea what you are getting at because it even states that the truck plowed into the I-beam. I suppose it withstood the impact but the fire is what damaged it?

It all began when a car pulled in front of a gasoline truck to avoid missing an exit, and the truck, to keep from hitting the car, swerved and plowed into a bridge support under I-65 Southbound. The truck, which was hauling 37,475 liters (9,900 gallons) of fuel, exploded into a fireball that was estimated to have reached more than 1,093C (2,000F) at one point. The heat caused several of the bridge's steel girders to sag approximately 2 to 3 meters (7 to 10 feet), collapsing the structure.

It says that some girders sagged approximately 7 to 10 feet, but doesn't mention what type of damage was done to the girders with impact.

Also, the girders sagged, not collapsed. I see what you are getting at and it is a good find. But still doesn't fully change my mind. Comes close, but not fully.

The truck, which was hauling 37,475 liters (9,900 gallons) of fuel,

Maximum Fuel Capacity 11,489 gal Boeing 757-200

www.boeing.com...

Im estimating the bridge is 200 ft long or 1/5 the size of the WTC towers.
The truck was carrying 9900 gallons a fully fueled 757 carries 11489 gallons or 16% more than what the truck can carry.

So how can 16% more in fuel collapse and pulverize a structure 5 times bigger than the bridge?

[edit on 7-11-2006 by etshrtslr]

[edit on 7-11-2006 by etshrtslr]

Originally posted by etshrtslr
It should all be realitive....the whole length and breadth of the bridge burned....That in noway happened at the WTC towers.....at most the upper third of the buildings burned for less than one hour......the middle third and lower third should have been able to support the upper third of the building.

Relative how? The I-beam of the bridge failed along it's entire length. That means that the fire was able to heat the entire mass of that beam to it's failure point. The entire length of the beam failed.

The I-beams of the WTC towers were much smaller in size. With their verticle orientation their load was compressive. This means that their load was carried by the cross-section of the beam instead of it's length like the beams of the bridge. The WTC beams only had to be heated at a specific point for total failure to occur.

The fire on the bridge was a gasoline fire, while the fires in the WTC were initially Jet-A. Jet-A has a higher heat energy (135,000 BTU/gal.) than gasoline (125,000 BTU/gal.). The structure of the bridge was open as compaired to the closed structure of the WTC towers. Granted this allowed the bridge fire unimpeded access to oxygen, but it also allowed for the dissipation of heat.

Originally posted by Griff
Bolded by me. This sentence is wrong. The I-beam sagged. It did not lose structural integrity. It did not completely disintegrate upon itself. And as stated before, it did not eject itself.

Furthermore, I have no idea what you are getting at because it even states that the truck plowed into the I-beam. I suppose it withstood the impact but the fire is what damaged it?

It says that some girders sagged approximately 7 to 10 feet, but doesn't mention what type of damage was done to the girders with impact.

Also, the girders sagged, not collapsed. I see what you are getting at and it is a good find. But still doesn't fully change my mind. Comes close, but not fully.

First the truck hit the support not the beam.

I am correct in stating that the beam failed. When the beam sagged it was because it was incapable of bearing it's own weight let alone the load that it was designed to carry. Try this. Take a piece of uncooked spaghetti and see how many Cheerios that you can put on it while holding it level at one end. Then cook the spaghetti and try it again.

JIMC5499,

The I-beams of the WTC towers were much smaller in size.

I dont know but I suspect that the amount of steal in the WTC towers was of a magnitude of some multiple more than what was in the bridge.

If the bridge did not collapse with roughly the same amount of fuel consuming it as the towers why whould the towers collapse with a multiple more amount of steel, when the amount of fuel was not enough to heat enough steel to cause a collapse in the bridge?

Originally posted by JIMC5499
I am correct in stating that the beam failed. When the beam sagged it was because it was incapable of bearing it's own weight let alone the load that it was designed to carry.

Since the beam is still there and attached, it did not fail...it sagged. Sagging beams still have some of their structural integrity.

As the other person in this thread has also stated. How is the approximate same amount of fuel (16% larger) suppossed to fail 47 core columns and over 800 exterior columns when it didn't even fully fail one I-beam in your bridge example? Plus, in the WTC, the fuel was spread out (and suppossedly some of it went down the elevator shafts) while on this bridge, the fuel was concentrated.

Also, comparing a horizontal beam with a verticle column is not a good comparison. A column in compression is in compression in total. A horizontal beam is in compression on the top surface while in tension on the bottom surface. I can see sagging happening just like I can see the trusses at the WTC happenning. Buckling is a different matter entirely.

Try this. Place your spaghetti noodle where you have 47 in a core and over 800 perimeter. Now place a sheet of cardboard on them so they stay up. Assume they are supported into the foundation. Now, see how many you have to take out to have the cardboard fall straight down. Falling straight down is the key.

Originally posted by etshrtslr
Idont know but I suspect that the amount of steal in the WTC towers was of a magnitude of some multiple more than what was in the bridge.

If the bridge did not collapse with roughly the same amount of fuel consuming it as the towers why whould the towers collapse with a multiple more amount of steel, when the amount of fuel was not enough to heat enough steel to cause a collapse in the bridge?

All of the steel in the towers didn't have to fail for them to collapse. Remember, both towers were structures that had just absorbed a tremendous amount of force from the impact of the airliners. Several I-beam columns had to have been sheared or weakened from just the impact alone. Of those remaining all that had to fail because of the fire, were enough columns in the area of impact, for those remaining to be loaded beyond their Yeild Point.

People seem to think that the entire beam had to fail, this isn't true. When a beam is being used as a column, the main force on it is compressive. The load that can be supported by a column is a function of the area of it's cross section. A failure plane thinner than a piece of paper can cause the failure of the entire column.

Once the upper sections of the towers started to move, it became a Dynamic Load instead of the Static Load that the design was intended to handle.

Originally posted by Griff
Try this. Place your spaghetti noodle where you have 47 in a core and over 800 perimeter. Now place a sheet of cardboard on them so they stay up. Assume they are supported into the foundation. Now, see how many you have to take out to have the cardboard fall straight down. Falling straight down is the key.

Let me throw a baseball at it first. People seem to keep forgetting that a large plane smacked in to this structure. How many columns were taken out there?

Try this one. Take the cardboard center from a roll of toilet paper and stand it on end. Now set a brick on top of it. It should hold the brick with no problem. Next, lift the brick about 6 inches and drop it on to the cardboard center. What happens? Even better, while the cardboard center is supporting the brick, shoot it with a BB gun.

Falling straight down isn't the key. The towers didn't fall straight down.

Hey Jim,

What about WTC7? Did fire bring that down into it's own footprint too?

All of the steel in the towers didn't have to fail for them to collapse.

I have a hard time believing that....maybe a partial collapse but not the total catastrophic pulverizing material ejecting collapse that occured.

It would require more energy to initiate that collapes than the jet fuel provided. Remember the truck had just about the same amount of fuel as the plane and the building had many multiple of tons more in steel than the bridge and yet the bridge did not collapse.

If your logic is correct then that bridge would have fallen down on the highway below it and the picture would show that. But there is no parallel with what happened at the WTC at all.

Originally posted by JIMC5499
Try this one. Take the cardboard center from a roll of toilet paper and stand it on end. Now set a brick on top of it. It should hold the brick with no problem. Next, lift the brick about 6 inches and drop it on to the cardboard center. What happens? Even better, while the cardboard center is supporting the brick, shoot it with a BB gun.

Question. Would said cardboard roll disintegrate into itself? Also, would said brick be pulverized into fine particulates?

Originally posted by denythestatusquo
If your logic is correct then that bridge would have fallen down on the highway below it and the picture would show that. But there is no parallel with what happened at the WTC at all.

My only purpose in showing the bridge is to show that a steel beam can be heated to failure by a fire. Other than that I am making no compairison between the two events. If a gasoline fire can cause that huge I-beam to warp that badly, then how come it is so hard to believe that a jet fuel fire can't do the same to the smaller I-beams in the WTC tower's structure?

only a few floors were affected by fire, how did the rest of the building get shredded?

why didn't the WTC deform strongly before collapse? this bridge sagged quite a bit and did not fall, wouldn't the WTC similarly have shown some leaning, especially the north tower, with its antenna? even the south tower is not really debatable, because in case of failure, the uppwer portion would have fallen off had it continued its original leaning motion - before it's supports mysteriously vanished, initiating near-freefall collapse.

In the 70's one of the towers was on fire over the period of a weekend. a very intense fire. much more devastating then the fires of 9/11. Firefighters were actually reporting on their radios that alot of the fires were almost extinguished just about the time the true terrorists detonated the bombs inside.

Originally posted by JIMC5499
My only purpose in showing the bridge is to show that a steel beam can be heated to failure by a fire.

Then show it. All that fuel concentrated and it didn't even cause a total failure, just warping. When you accept that warping is not the same as total failure then maybe this thread can progress. And though the WTC beams individually were smaller, there was a much greater mass of steel over-all. You can say not all of it would have to be totally failed, but all of this fuel didn't even fail one bridge, as shown.

Also, before the loads are mentioned again, the perimeter columns were supposed to have a FoS of 5 on those floors. You would have to fail a damned lot of perimeter columns on a particular floor (something we DID NOT SEE) to cause problems in those regards.

And it would also help to remember that everything is in proportion, and skyscrapers are over-engineered for safety anyway. Supporting more load does NOT mean easier to fail. To the contrary, it means that much more structure to support it, more redundancy for safety. That's good engineering.

[edit on 7-11-2006 by bsbray11]