How Does Aluminum Cut Steel?

reply to post by eyewitness86


Denial is a powerful emotional and mental self defence mechanism, most of America is experiencing that right now.

And then we have WTC7 which had steel cut by unknown means, the clean up for this site was the fastest of any sites and we wonder why.

They didn't want anybody poking around finding things out.

Originally posted by jfj123
BINGO !!!!!!
Now are you saying that there were no computer monitors, keyboard, mice, towers, laptops, furniture, electric wire insulation, etc..... ? that would have been burning causing black smoke???

Again you are not reading. Did you miss the part about there being NO new fuel added to the fire? The computers and other stuff were there all along, not added later.

But regardless it's a mute argument, even if the fire didn't start cooling it would not cause a global collapse of thousands of tons of steel in an hour...

Not enough temperature and more importantly an inefficient transfer of thermal energy.

reply to post by ANOK

Again you are not reading. Did you miss the part about there being NO new fuel added to the fire? The computers and other stuff were there all along, not added later.

Did all the fires start everywhere at once? No. So as the fires consumed more areas, new fuel was added. Maybe you should try reading yourself or stop posting snotty comments

Originally posted by ULTIMA1

Well i can see you did not read my post and do research or you would have noticed that their was not fireproofing in the towers untill after the 1975 fire.

Actually, there was from the first day of finished construction. Asbestos was applied in conjunction with several plies of sheetrock/drywall as a fire retardant in lieu of heavier concrete and on the steel.

I did find the following link and excerpt. It was done during construction as was common when asbestos could legally be used as a fire retardant. Vincent Dunn is either a current or ex-fireman. The following is not an accurate description of the twin towers but simply discussing commercial buildings in general. I present it to validate asbestos was used during construction and maintained while the twin towers were standing.

vincentdunn.com...

"Concrete removal

Since the end of WWII builders designed most of the concrete from the modern high-rise constriction. First concrete they eliminated was the stone exterior wall. They replace them with the “curtain walls of glass, sheet steel, or plastics. This curtain wall acted as a lightweight skin to enclose the structure from the outside elements. Next the 8-inch thick concrete floors went. They were replaced with a combination of 2 or 3 inches of concrete on top of thin corrugated steel sheets. Next the masonry enclosure for stairs and elevators were replaced with several layers of sheet rock. Then the masonry smoke proof tower was eliminated in the 1968 building code. It contained too much concrete weight and took up valuable floor space. Then the solid steel beam was replace by the steel truss. And finally the concrete and brick encasement of steel columns girders and floor supports was eliminated. A lightweight spray-on coating of asbestos or mineral fiber was sprayed over the steel. This coating provided fireproofing. After asbestos was discovered hazardous vermiculite or volcanic rock ash substance was used as a spray-on coating for steel. Outside of the foundation walls and a thin 2 or 3 inches of floors surface, concrete has almost been eliminated from high-rise office building construction. If you look at the WTC rubble at ground zero you see very little concrete and lots of twisted steel."

The reason people see "very little concrete" at ground zero is because the vast majority of it violently erupted, blew out and fell in pulverized dust everywhere else, including the Hudson River. That is what that volcanic looking pyroclastic flow from the twin towers meant.

Many firemen, if not all, detest high rise buildings. They see them as highly potential death traps, and they are correct. Mr. Dunn is showing his bias. Therefore, he is not going to have an objective view when describing high rise construction. It shows in what he presents. Other than some of his bias getting in his way of objectivity, he is accurate from what I have researched. Being accurate in part but not whole, does not necessarily mean the entire truth has been told.

Originally posted by Pilgrum

We've probably gone a bit beyond the thread topic here but considering it's a virtual certainty (beyond any reasonable doubt) the planes did pass through the outer walls to deliver the load of fuel inside the buildings and cause those fires...

Your visibility was so extremely sharp you actually saw planes penetrating buildings? Is there something available that shows any planes actually penetrating either tower? I did not see that happen through massive balls of orange flames and dense black carbon smoke. That leaves me highly puzzled, by those explicitly claiming to have seen any planes penetrating either of the twin towers.

It will not do any good to ask me something like this, "Well, if they didn't penetrate the buildings where did they go?" That would be a tangent, and not providing proof of visibility few, if any, other people claim to have had, the vast majority have never claimed to have had.

reply to post by jfj123


When it comes to plastic, plastic is carbon based in petroleum by-product. The plastic is spending more time melting and giving off black carbon smoke than actully burning and efficiently heating (hot heat), or adding any heat to an already existing fire. Plastic adds a great deal of carbon smoke but not hot heat, and actually robs flames of thermal energy to heat due to melting not actually burning.

Yes, melting plastic automatically becomes oxygen starved. Hence, the black carbon smoke pouring from melting plastic.

Hot heat burns hot when pure oxygen is added. Hot heat is not necessarily produced automatically when combined with the atmospheric air we breathe. The air we breathe is full of impurities and other gases. Which causes carbon based fossil fuel to burn off those unnecessary impurities gases, in order to get to a purer form of atmospheric oxygen. That takes away from the efficiency of carbon fossil fuel based fires keeping them cooler fires.

Carbon based fossil fuel fires first have to burn off all their carbon, and then burn off the carbon and other atmospheric impurities and gases, to get to the the much smaller quantity of oxygen laced in the atmospheric air we breathe.

Originally posted by ANOK
Again you are not reading. Did you miss the part about there being NO new fuel added to the fire? The computers and other stuff were there all along, not added later.

But regardless it's a mute argument, even if the fire didn't start cooling it would not cause a global collapse of thousands of tons of steel in an hour...

Not enough temperature and more importantly an inefficient transfer of thermal energy.

Fire, by its very nature, is not a stationary thing and in the case of a large uncontrolled fire it's the fire finding new fuel sources and not the other way round. The relative proportions of fuel types were changing due to the finite quantity of jet fuel reducing as it progressed and that's what's evident in the smoke properties. I'd suggest the increasing blackness of the smoke is indicating fullerene type compounds from burning synthetic materials and rubber products becoming the dominant fuel source.

Originally posted by OrionStars
reply to post by jfj123

 

Yes, melting plastic automatically becomes oxygen starved. Hence, the black carbon smoke pouring from melting plastic.

My point is that just because some plastic is melting in a huge fire, it doesn't mean the entire fire is oxygen starved. As example, put a couple hundred tires in a pile in the middle of a forest fire and burn the tires. They will give off black smoke but that doesn't mean the entire forest fire is oxygen starved.

reply to post by jfj123


The discussion began as to if black smoke indicates a fire is oxygen starved. That was in general. Yes, it does.

Now you have changed it to plastic. Plastic can add to oxygen starvation, particularly when the accelerant (fuel source), is carbon based fossil fuel. That was my point in general and in specifics.

I cannot consider plastic or rubber a fuel source. Without an accelerant and ignition, or an already existing fire, plastic or rubber is highly unlikely to self-ignite from any friction. They may feed carbon smoke, rather than help a fire become hot heat, but are not actually fuel sources. Fuel sources are normally an accelerant, and ignition, with a flame or friction, is the catalyst which sets the accelerant to starting firing.

The thermal energy of a flame for temperature is not measured by the outside of the flame, but the inside at its hottest point instead. To rapidly cause something like steel to begin to compromise, the flame would have to be directly applied to the steel for some length of time depending on the type of fire. Do you realize what the actual temperature in a blast furnace is for even beginning to compromise steel, much less melt it down during the recycling process? It takes time for the steel to become internally hot enough to compromise any other part of the steel.

People have repeatedly made the valid point that kerosene could not compromise the WTC steel, causing complete building collapse, in 1 hour or 3 hours or 24 hours. Never in the history of steel and concrete buildings has there ever been a building collapse from any fire. What will be standing is almost all, if not all, of a skeletal hulk of the original building.

I also know the WTC steel had asbestos spray, including on the trusses, from the day the building was finished and open for business. More was applied after WTC 1 experience a 3 plus hour, 6 story blowtorch type fire in 1975.

One other mistake was made by NIST and the "official" report. The documentaries touting the official report said a truss gave way on the perimeter wall and similated version was shown.

The "official" report problem is there was no evidence of fire on the perimeter wall, to even begin to compromise any steel under any fire conditions. The perimeter wall is the exterior, not interior, wall. In order for that to happen, a clearly seen raging fire would have had to burn out the the drop ceiling and climb approximately 12' to get to the truss from the reinforced 4" deep concrete floor on which the fire was sitting. That would have easily been seen by any witness observing from the outside looking at the exterior wall the truss has been touted to have dropped.

If they has moved it to the interior wall, that means the truss would have dropped toward the exterior wall. Taking whatever fire was on that asbestos sprayed steel and moving it away from the asbestos sprayed core. Without continuing to apply accelerant to steel, the fire will burn itself out. Steel, which is not rusted, has never fed fires.

Originally posted by OrionStars
reply to post by jfj123

 

The discussion began as to if black smoke indicates a fire is oxygen starved. That was in general. Yes, it does.

Still no it doesn't. Once again, just because you see black smoke, it doesn't automatically mean every time without exception, the fire is starved of oxygen. I even gave you an example of a forest fire burning and a pile of tires in the middle.

Now you have changed it to plastic.

I have changed nothing. My point has stayed the same the entire time. I have however, given you an alternate reason as to why you may see black smoke in a fire.

Plastic can add to oxygen starvation, particularly when the accelerant (fuel source), is carbon based fossil fuel. That was my point in general and in specifics.

My point is that just because you see black smoke, it doesn't automatically mean the fire is oxygen starved. This has been my point the entire time.

I cannot consider plastic or rubber a fuel source. Without an accelerant and ignition, or an already existing fire, plastic or rubber is highly unlikely to self-ignite from any friction.

I never said friction started any fires. Once the fires were started, many office items burned and kept the flames burning. Some of them were items that would create black smoke.

Do you realize what the actual temperature in a blast furnace is for even beginning to compromise steel, much less melt it down during the recycling process? It takes time for the steel to become internally hot enough to compromise any other part of the steel.

Jet fuel burns at 800° to 1500°F. Steel melts at 2750°F. Experts agree that for the towers to collapse, their steel frames didn't need to melt, they just had to lose some of their structural strength. What happens is that the steel tries to expand at both ends, but when it can no longer expand, it sags and the surrounding concrete cracks.
Steel loses about 50 percent of its strength at 1100°F," notes senior engineer Farid Alfawak-hiri of the American Institute of Steel Construction. "And at 1800° it is probably at less than 10 percent."

People have repeatedly made the valid point that kerosene could not compromise the WTC steel, causing complete building collapse, in 1 hour or 3 hours or 24 hours. Never in the history of steel and concrete buildings has there ever been a building collapse from any fire.

Well we know this is simply not true. There have been building collapses from fires. I have seen several myself. FYI: One of my jobs is fire restoration.

What will be standing is almost all, if not all, of a skeletal hulk of the original building.

Here are a few quotes from a fire chief.
"I have never seen melted steel in a building fire," says retired New York deputy fire chief Vincent Dunn, author of The Collapse Of Burning Buildings: A Guide To Fireground Safety. "But I've seen a lot of twisted, warped, bent and sagging steel.

Also keep in mind that never in the history of steel and concrete buildings has there ever been a group of terrorists purposely flying a 767 into a skyscraper at high speed.

Originally posted by OrionStars
Actually, there was from the first day of finished construction. Asbestos was applied in conjunction with several plies of sheetrock/drywall as a fire retardant in lieu of heavier concrete and on the steel.

You missed this in my post.

Commissioner O'Hagan said that the absence of fire-stopper material in gaps around the telephone cables had allowed the blaze to spread to other floors within the cable shaft.

[edit on 26-12-2007 by ULTIMA1]

Originally posted by jfj123
Still no it doesn't. Once again, just because you see black smoke, it doesn't automatically mean every time without exception, the fire is starved of oxygen.

jnocook.net...

A jet fuel fire would produce great quantities of smoke, which would reduce the radiant heat energy entering structural components. According to G. Charles Clifton HERA structural engineer, speaking of the fires in the Towers; In my opinion, based on available evidence, there appears no indication that the fires were as severe as a fully developed multi-story fire in an initially undamaged building would typically be.

911research.wtc7.net...

Jet fuel (kerosene) only burns at a fraction of the temperature needed to melt steel. In any case, the fuel did not last long, as much was consumed in the impact fireballs, and the rest would have evaporated and burned in under 5 minutes. Thereafter the fires were far less severe than other skyscraper fires (such as the 19-hour One Meridian Plaza blaze in 1991). Few flames were visible, and the black smoke indicated the fires were oxygen-starved. Survivors passed through the WTC 2's crash zone, and firefighters who arrived there described "two pockets of fire".

Originally posted by ULTIMA1

Originally posted by jfj123
Still no it doesn't. Once again, just because you see black smoke, it doesn't automatically mean every time without exception, the fire is starved of oxygen.

jnocook.net...

A jet fuel fire would produce great quantities of smoke, which would reduce the radiant heat energy entering structural components. According to G. Charles Clifton HERA structural engineer, speaking of the fires in the Towers; In my opinion, based on available evidence, there appears no indication that the fires were as severe as a fully developed multi-story fire in an initially undamaged building would typically be.

Great info about jet fuel fires and the temps that they burn at. Thanks for the contribution.

However, last time I checked, carpeting, paper, office furniture, plastics, etc, weren't a component typically found in jet fuel.

Maybe you should do some research on typical structural fire temps and the impact that plastics can have on the temps before you make posts like these.

Just a suggestion.....

Originally posted by MikeVet
Maybe you should do some research on typical structural fire temps and the impact that plastics can have on the temps before you make posts like these.

Just a suggestion.....

Oh but i have, have you ?

reply to post by ULTIMA1


Jet fuel burns at 800° to 1500°F. Steel melts at 2750°F. Experts agree that for the towers to collapse, their steel frames didn't need to melt, they just had to lose some of their structural strength. What happens is that the steel tries to expand at both ends, but when it can no longer expand, it sags and the surrounding concrete cracks.
Steel loses about 50 percent of its strength at 1100°F," notes senior engineer Farid Alfawak-hiri of the American Institute of Steel Construction. "And at 1800° it is probably at less than 10 percent."

Originally posted by ULTIMA1

Originally posted by MikeVet
Maybe you should do some research on typical structural fire temps and the impact that plastics can have on the temps before you make posts like these.

Just a suggestion.....

Oh but i have, have you ?

Excellent then post the information. Thanks.

Originally posted by jfj123
Steel loses about 50 percent of its strength at 1100°F," notes senior engineer Farid Alfawak-hiri of the American Institute of Steel Construction. "And at 1800° it is probably at less than 10 percent."

But the firemen who made it to the 78th floor of the South tower only reported small isolated fires. No big jet fuel fires.



[edit on 26-12-2007 by ULTIMA1]

Originally posted by ULTIMA1

Originally posted by MikeVet
Maybe you should do some research on typical structural fire temps and the impact that plastics can have on the temps before you make posts like these.

Just a suggestion.....

Oh but i have, have you ?

As stated above, you said you have information about typical structural fire temps. Could you please post the info along with your source?

Thanks.

Originally posted by jfj123
As stated above, you said you have information about typical structural fire temps. Could you please post the info along with your source?

Thanks.

I notice you did not respond to my post about the jet fuel fires.

Originally posted by ULTIMA1

Originally posted by jfj123
As stated above, you said you have information about typical structural fire temps. Could you please post the info along with your source?

Thanks.

I notice you did not respond to my post about the jet fuel fires.

What post? Please be specific.