Chemistry/Physics Behind the Attacks

Originally posted by Griff
Would the temperatures be enough to vaporize the steel? NIST found that some of the steel had been vaporized. Would these magical underground stoves been able to vaporize steel?

First, lets clarify something. The steel in question was not “vaporized,” it eroded in a process known as hot corrosion.

And the answer to your question is: yes. In fact that process happens at a lower temperature then needed to melt the steel in a steel mill.

This is generally around 1000 ° C

more

Hope this helps.

Basically from what I just read from your NIST link is "we don't know" what happened. They are trying to pull anything that has sulfur in it out they arses. Salt water air, acid rain (yeah, it was raining that day), etc. Don't tell me it was gypsum either because gypsum is used for fire protection. But, for arguments sake, I will say that maybe the eutitic (sp?) reaction was from one of these sources. What then? Could any steel structure collapse globally from fires (many steel structures have gypsum board)? If so, isn't it time we re-think our designs of steel skyscrapers to not include gypsum?

Don't forget the biggest source of sulfur at Ground zero. Gypsum.

They were ankle deep in the stuff all over Manhatan.

Originally posted by HowardRoark
Don't forget the biggest source of sulfur at Ground zero. Gypsum.

They were ankle deep in the stuff all over Manhatan.

Wasn't just gypsum.

Originally posted by HowardRoark
It sounds to me like you don’t really understand how thermodynamics works. How the energy of a chemical reaction is converted to temperature.

The claim that it is impossible for temperatures of a jet fuel fire, or for any other hydrocarbon fire to exceed 800 °C is just plain wrong.

Any fire in an enclosed area will quickly surpass that temperature.

Even the ASTM fire tests exceed that temperature.

You still aren't going anywhere with this.

Please explain to us, in detail, with credible sources, what circumstances could have allowed the WTC fires to have exceeded 800°C.

You don't seem to understand thermodynamics, because most of that heat would be carried off by air, especially when the smoke turned black. And conductivity of steel. Both of those things, you totally and conveniently ignore, among others, to pretend NIST is on to something.

Steel was vaporized/disintegrated.

Here is a gif of that happening to the spire at the end of the collapse.....




Here is more evidence of thermite at the towers..............

Pic of thermite reaction:




Here is an example on video:

Thermite reaction video example


Now here is rare footage of the south tower clearly showing a thermite reaction pouring out of a hole in the corner. Notice the obvious difference between the conventional fires also burning.

Thermite reaction in corner of south tower video

Originally posted by bsbray11

Originally posted by HowardRoark
It sounds to me like you don’t really understand how thermodynamics works. How the energy of a chemical reaction is converted to temperature.

The claim that it is impossible for temperatures of a jet fuel fire, or for any other hydrocarbon fire to exceed 800 °C is just plain wrong.

Any fire in an enclosed area will quickly surpass that temperature.

Even the ASTM fire tests exceed that temperature.

You still aren't going anywhere with this.

Please explain to us, in detail, with credible sources, what circumstances could have allowed the WTC fires to have exceeded 800°C.

You don't seem to understand thermodynamics, because most of that heat would be carried off by air, especially when the smoke turned black. And conductivity of steel. Both of those things, you totally and conveniently ignore, among others, to pretend NIST is on to something.

exactly.

plus NIST determined that...........

"Using metallographic analysis, NIST determined that there was no evidence that any of the samples had reached temperatures above 600 degrees C" (p. 88/142)

You see howard..............it's not that the fires had to reach 800 C. It's that the STEEL had to reach those temperatures which it clearly did not even according to NIST.

The failure of those columns due to fire is utterly ludicrous and there is ZERO data to support this claim.

The third stage of fire growth is called flashover. It is the most significant moment of any structure fire. As combustible gases are produced by the two previous stages they are not wholly consumed. They rise and form a superheated gas layer at the ceiling. As the volume of this gas layer increases, it begins to bank down to the floor, heating all combustible objects regardless of their proximity to the burning object. In a typical structure fire, the gas layer at the ceiling can quickly reach temperatures of 1500 degrees Fahrenheit (800 C – HR) . If there is enough existing oxygen, usually near floor level, flashover occurs and everything in the room breaks out into open flame at once. The instantaneous eruption into flame generates a tremendous amount of heat, smoke, and pressure with enough force to push beyond the room of origin through doors and windows. The combustion process then speeds up because it has an even greater amount of heat to move to unburned objects.
Flashover is a critical stage of fire growth for two reasons. First, no unprotected living thing in a room where flashover occurs will survive and the chance of saving lives drops dramatically. Second, flashover creates a huge jump in the rate of combustion, and a significantly greater amount of water is needed to reduce the burning material below its ignition temperature. A post-flashover fire burns hotter and moves faster, requires more resources for fire attack, and compounds the problems of search and rescue, exposure protection, and containment.

fire.ucdavis.edu...

There is fairly broad agreement in the fire science community that flashover is reached when the average upper gas temperature in the room exceeds about 600°C. Prior to that point, no generalizations should be made: There will be zones of 900°C flame temperatures, but wide spatial variations will be seen. Of interest, however, is the peak fire temperature normally associated with room fires. The peak value is governed by ventilation and fuel supply characteristics [14] and so such values will form a wide frequency distribution. Of interest is the maximum value which is fairly regularly found. This value turns out to be around 1200°C, although a typical post-flashover room fire will more commonly be 900~1000°C. The time-temperature curve for the standard fire endurance test, ASTM E 119 [15] goes up to 1260°C, but this is reached only in 8 hr. In actual fact, no jurisdiction demands fire endurance periods for over 4 hr, at which point the curve only reaches 1093°C.

www.doctorfire.com...

The fire was ignited in the living area of the flat and progressed to flashover after approximately 24 minutes. Initial burning was concentrated in the front of the living area closest to the ventilation opening. To accelerate the time to flashover the Fire Brigade was asked to intervene by breaking a single windowpane in the kitchen area. This took place 21 minutes and 30 seconds from ignition. Following flashover the Fireline boards over the windows to the floor above were subject to a heat flux of approximately 30kW/m² (peak plume temperature in excess of 500°C). The timber frame of the window would, if exposed, have ignited. Peak temperatures in the living area of the fire flat reached approximately 1000°C and remained at this level until the test was stopped at 64 minutes having reached one of the planned termination criteria.
Based on measurements taken of fuel mass loss, the peak rate of heat release has been calculated as approximately 6 MW.
The decision to stop the test was taken on the basis of predetermined termination criteria, one of which was related to duration of fire attack on exposed joists. The fire was extinguished by fire brigade intervention through the front door of the fire flat.

www.mace.manchester.ac.uk...



Of additional interest is this independent study of a long span truss in a fire under WTC conditions.

Numerical analyses were conducted using Vulcan, of the composite trusses with and without accounting for the restraint provided by a supporting column, simply representing the extreme and the middle floors among the fire exposed levels, up to 60 minutes of the standard fire. The numerical analyses demonstrated that the protected composite trusses would resist 60 minutes of the standard fire within a deflection of L/100, under loadings of 4.8kN/m2 and 3.9kN/m2. Unprotected simply supported trusses initially lost stability at 12.5 and 13.4 minutes due to buckling of the second compressive web diagonal. Both of the protected trusses with a supporting column deflected approximately L/90 at 60 minutes of the standard fire without any local instability occurring. The unprotected composite truss with a supporting column was shown to resist for 16.1 and 18.0 minutes of the standard fire before the progressive buckling of web compression diagonals caused a loss of stability. This would undoubtedly have re-stabilized when catenary action of the top chord and slab reinforcement took effect, but their tensile strength, together with the tying strength of the beam-column connections, would then become critical. For both types of support condition the behavior of the unprotected truss was relatively insensitive to the level of loading.

fire-research.group.shef.ac.uk...

Originally posted by Jack Tripper
exactly.

plus NIST determined that...........

"Using metallographic analysis, NIST determined that there was no evidence that any of the samples had reached temperatures above 600 degrees C" (p. 88/142)

[....]

You see howard..............it's not that the fires had to reach 800 C. It's that the STEEL had to reach those temperatures which it clearly did not even according to NIST.

The failure of those columns due to fire is utterly ludicrous and there is ZERO data to support this claim.

Yes but as the report says there was only a tiny proportion of the steel recovered, only 12 core columns for instance and only some of those 12 from the affected floors.

E.2 INVENTORY OF RECOVERED STEEL

A total of 236 recovered pieces of WTC steel were cataloged; the great majority belonging to the towers, WTC 1 and WTC 2. These samples represented a quarter to half a percent of the 200,000 tons of structural steel used in the construction of the two towers. The NIST inventory included pieces from the impact and fire regions, perimeter columns, core columns, floor trusses, and other pieces such as truss seats and wind dampers.

The original, as-built locations of 42 recovered perimeter panels and 12 recovered core columns were determined, based on markings and geometry of the columns. Samples were available of all 12 strength levels of perimeter panel steel, the two strength levels of the core column steel that represented 99 percent of the total number of columns, and both strength levels used in the floor trusses.

A number of structural pieces were recovered from locations in or near the impact- and fire-damaged regions of the towers, including four perimeter panels directly hit by the airplane and three core columns located within these areas. These pieces provided opportunity for failure and other forensic analyses.

The collection of steel from the WTC towers was sufficient for determining the quality of the steel and, in combination with published literature, for determining mechanical properties as input to models of
wtc.nist.gov...

As you say, the samples analysed did not reach the required temperatures. But they hardly had any, the main purpose was to analyse it's properties for simulations and calculative purposes.

As for the molten metal, word on the street was that it was more than likely aluminium from the aircraft melting (showing that temperatures would be in the region of at least 600 degress C). If it was thremite how come that was the only area it was coming from anyway? Surely it would need to affect a huge number of exterior columns, due to the redundancies and all of course. If they didn't need to use thermite on the exterior and only on the core, then why that bit? To leave a tantalising clue?

Yeah, Howard, I especially liked parts like this,

The time-temperature curve for the standard fire endurance test, ASTM E 119 [15] goes up to 1260°C, but this is reached only in 8 hr. In actual fact, no jurisdiction demands fire endurance periods for over 4 hr, at which point the curve only reaches 1093°C.

www.doctorfire.com...

But when you only have about an hour, and no evidence of a flashover, hmm. And even then, the fire isn't staying in one place, and heating one place, but roaming around the whole time. That's probably why you didn't even get a flashover in the first place, Howard.

Or do you have evidence that there was such an event?

Seriously, I still am waiting to see how any of this is relevant to the WTC fires. And then once you finally come up with that, I'll be waiting for the evidence of sufficiently heated steel. And then when you finally come up with that, I'll be waiting for explanations for all the physics problems of the collapses, from once they were underway. And there's more beyond that, but you'll never get that far, so...

Originally posted by AgentSmith


As for the molten metal, word on the street was that it was more than likely aluminium from the aircraft melting (showing that temperatures would be in the region of at least 600 degress C). If it was thremite how come that was the only area it was coming from anyway? Surely it would need to affect a huge number of exterior columns, due to the redundancies and all of course. If they didn't need to use thermite on the exterior and only on the core, then why that bit? To leave a tantalising clue?

Word on the street!

Hahaha!

Well sorry but physics dictate that you can tell the nature of the molten metal by it's color and consistency.

How about word from a physics professor?

It was a salmon color and therefore indicative as being structural steel.

"We see from the photograph above that solid metal slag existed at salmon-to-yellow-hot temperature (approx. 1550 - 1900 oF, 845 - 1040 oC.) The temperature is well above the melting temperatures of lead and aluminum, and these metals can evidently be ruled out since they would be runny liquids at much lower (cherry-red or below) temperatures. However, the observed hot specimen could be structural steel (from the building) or iron (from a thermite reaction) or a combination of the two. Additional photographs of the hot metal could provide further information and advance the research."

THIS.....my naive friend.......is molten aluminum....




Big difference.


There is evidence of thermite mostly within the core but perhaps the plane impact and this gaping hole alowed for it to react and pour out in that one place.

I don't believe that thermite was used throughout the external grid.

Originally posted by bsbray11
Yeah, Howard, I especially liked parts like this,

The time-temperature curve for the standard fire endurance test, ASTM E 119 [15] goes up to 1260°C, but this is reached only in 8 hr. In actual fact, no jurisdiction demands fire endurance periods for over 4 hr, at which point the curve only reaches 1093°C.

www.doctorfire.com...

But when you only have about an hour, and no evidence of a flashover, hmm. And even then, the fire isn't staying in one place, and heating one place, but roaming around the whole time. That's probably why you didn't even get a flashover in the first place, Howard.

Or do you have evidence that there was such an event?

Seriously, I still am waiting to see how any of this is relevant to the WTC fires. And then once you finally come up with that, I'll be waiting for the evidence of sufficiently heated steel. And then when you finally come up with that, I'll be waiting for explanations for all the physics problems of the collapses, from once they were underway. And there's more beyond that, but you'll never get that far, so...

Owned!

Good job bsbray.

That is exactly what I was thinking when reading that bloated out irrelevant distraction of a post by howard.

The fires at the WTC were not getting worse. They were consistenly dying down in the mere 60 minutes/ hour 45 minutes respectively that they burned.

There is no evidence of "flashover" whatsoever nor was there NEAR enough time for the steel to heat to anywhere near 1000 C!

Maybe they have a copy of the blueprints

Yamasaki, Minoru [minō'rOO yämäsä'kē]
Pronunciation Key

Yamasaki, Minoru , 1912–86, American architect, b. Seattle. Yamasaki worked for prominent architectural firms in New York City from 1937 until 1949, when he formed his own company. In 1951 he designed the Lambert–St. Louis Municipal Air Terminal, an impressive concrete groin-vault construction. In his design (1954) for the U.S. consulate general in Kobe, Japan, Yamasaki adapted elements of the Japanese aesthetic. His interest in ornament and sculptural form is revealed in buildings for the American Concrete Institute, the Reynolds Metal Company, and the McGregor Memorial Community Conference Center, Wayne Univ., all in Detroit. Yamasaki's design for the U.S. science pavilion at the Seattle Exposition, 1962, is famed for its soaring arches and Gothic tracery. His other major works include the Plaza Hotel, Los Angeles (1966), and the Eastern Airlines Unit Terminal, Boston (1968). He was a chief designer of the vast World Trade Center complex, New York City, which was destroyed by a terrorist attack in Sept., 2001.

Originally posted by HowardRoark

The third stage of fire growth is called flashover. It is the most significant moment of any structure fire. As combustible gases are produced by the two previous stages they are not wholly consumed. They rise and form a superheated gas layer at the ceiling. As the volume of this gas layer increases, it begins to bank down to the floor, heating all combustible objects regardless of their proximity to the burning object. In a typical structure fire, the gas layer at the ceiling can quickly reach temperatures of 1500 degrees Fahrenheit (800 C – HR) . If there is enough existing oxygen, usually near floor level, flashover occurs and everything in the room breaks out into open flame at once. The instantaneous eruption into flame generates a tremendous amount of heat, smoke, and pressure with enough force to push beyond the room of origin through doors and windows. The combustion process then speeds up because it has an even greater amount of heat to move to unburned objects.
Flashover is a critical stage of fire growth for two reasons. First, no unprotected living thing in a room where flashover occurs will survive and the chance of saving lives drops dramatically. Second, flashover creates a huge jump in the rate of combustion, and a significantly greater amount of water is needed to reduce the burning material below its ignition temperature. A post-flashover fire burns hotter and moves faster, requires more resources for fire attack, and compounds the problems of search and rescue, exposure protection, and containment.

fire.ucdavis.edu...

There is fairly broad agreement in the fire science community that flashover is reached when the average upper gas temperature in the room exceeds about 600°C. Prior to that point, no generalizations should be made: There will be zones of 900°C flame temperatures, but wide spatial variations will be seen. Of interest, however, is the peak fire temperature normally associated with room fires. The peak value is governed by ventilation and fuel supply characteristics [14] and so such values will form a wide frequency distribution. Of interest is the maximum value which is fairly regularly found. This value turns out to be around 1200°C, although a typical post-flashover room fire will more commonly be 900~1000°C. The time-temperature curve for the standard fire endurance test, ASTM E 119 [15] goes up to 1260°C, but this is reached only in 8 hr. In actual fact, no jurisdiction demands fire endurance periods for over 4 hr, at which point the curve only reaches 1093°C.

www.doctorfire.com...

The fire was ignited in the living area of the flat and progressed to flashover after approximately 24 minutes. Initial burning was concentrated in the front of the living area closest to the ventilation opening. To accelerate the time to flashover the Fire Brigade was asked to intervene by breaking a single windowpane in the kitchen area. This took place 21 minutes and 30 seconds from ignition. Following flashover the Fireline boards over the windows to the floor above were subject to a heat flux of approximately 30kW/m² (peak plume temperature in excess of 500°C). The timber frame of the window would, if exposed, have ignited. Peak temperatures in the living area of the fire flat reached approximately 1000°C and remained at this level until the test was stopped at 64 minutes having reached one of the planned termination criteria.
Based on measurements taken of fuel mass loss, the peak rate of heat release has been calculated as approximately 6 MW.
The decision to stop the test was taken on the basis of predetermined termination criteria, one of which was related to duration of fire attack on exposed joists. The fire was extinguished by fire brigade intervention through the front door of the fire flat.

www.mace.manchester.ac.uk...



Of additional interest is this independent study of a long span truss in a fire under WTC conditions.

Numerical analyses were conducted using Vulcan, of the composite trusses with and without accounting for the restraint provided by a supporting column, simply representing the extreme and the middle floors among the fire exposed levels, up to 60 minutes of the standard fire. The numerical analyses demonstrated that the protected composite trusses would resist 60 minutes of the standard fire within a deflection of L/100, under loadings of 4.8kN/m2 and 3.9kN/m2. Unprotected simply supported trusses initially lost stability at 12.5 and 13.4 minutes due to buckling of the second compressive web diagonal. Both of the protected trusses with a supporting column deflected approximately L/90 at 60 minutes of the standard fire without any local instability occurring. The unprotected composite truss with a supporting column was shown to resist for 16.1 and 18.0 minutes of the standard fire before the progressive buckling of web compression diagonals caused a loss of stability. This would undoubtedly have re-stabilized when catenary action of the top chord and slab reinforcement took effect, but their tensile strength, together with the tying strength of the beam-column connections, would then become critical. For both types of support condition the behavior of the unprotected truss was relatively insensitive to the level of loading.

fire-research.group.shef.ac.uk...

-----------------------------------------------------------------------------------------------

How did she survive "all that heat?!"



Woman Standing in North Tower hole:911review.com...

[edit on 15-2-2006 by XenonCodex]

Very nice link there Xenon.

Let's look at it further.

911review.com...

ERROR: 'Both Towers' Fires Diminished Before Their Collapses'

The often-repeated assertion that the fires in the Twin Towers were becoming less severe prior to the collapses is only partially true: The evidence shows that the South Tower's fires remained confined to a limited area and were dwindling before its collapse; but it shows that the North Tower's fires became more severe after the collapse of the South Tower.

It looks like theres more to the story than the oft-repeated black smoke=dying fires argument.

The caption for the picture of the woman standing at the edge of the hole says the following.

This photo of a person standing in the North Tower's impact hole was apparently taken rather early in the interval of time between jet impact and collapse.

So she withstood the heat by not being there when the fires were raging later on.

Jones take on the picture of glowing metal is entirely his opinion. Considering the quality of research he's shown, perhaps we shouldn't treat his opinions as gospel. He is saying that the temperature of the metal is between 1500-1900 F? Where does he get that figure from? I don't see any thermometers in the picture so he must have pulled that one from the same place he pulled his 4000lbs of explosives calculation.

While he is correct that aluminum would be runny at 1500-1900 F, It could be much lower than that and still be semi molten aluminum. It really doesn't make much sense that they would be dipping buckets made of steel into molten steel. Notice the lack of damage to the bucket in this 1900 degree envirnonment.


Someone esle once asked the following question, I saw no response to it so I thought I would repeat it.


Why is NIST unreliable when presented as evidence against demolition, but swallowed up when it can be twisted to support demolition?


Why do you guys accept NIST figures on anything? After all their conclusion was a gravity driven progressive collapse.

Originally posted by AgentSmith
[Yes but as the report says there was only a tiny proportion of the steel recovered, only 12 core columns for instance and only some of those 12 from the affected floors.

Um.. maybe this is because all the evidence was removed almost
immediately from the scene? Maybe if all the steel was not shipped
overseas we would have more columns from the effected floors.

Have any of you watched Professor Jones' Lecture?

Did you see the girl standing "unscathed" in the North Tower photo?

How about those Cardington Steel tests?

Maybe someone should try and find a construction worker that is still around and find out from them if the steel uprights were encased in concrete. From what I saw on my WTC video it appeared as if they were being prepared for encasement, but I could be wrong.

Originally posted by LeftBehind
Very nice link there Xenon.

Let's look at it further.

911review.com...

ERROR: 'Both Towers' Fires Diminished Before Their Collapses'

The often-repeated assertion that the fires in the Twin Towers were becoming less severe prior to the collapses is only partially true: The evidence shows that the South Tower's fires remained confined to a limited area and were dwindling before its collapse; but it shows that the North Tower's fires became more severe after the collapse of the South Tower.

It looks like theres more to the story than the oft-repeated black smoke=dying fires argument.

The caption for the picture of the woman standing at the edge of the hole says the following.

This photo of a person standing in the North Tower's impact hole was apparently taken rather early in the interval of time between jet impact and collapse.

So she withstood the heat by not being there when the fires were raging later on.

Jones take on the picture of glowing metal is entirely his opinion. Considering the quality of research he's shown, perhaps we shouldn't treat his opinions as gospel. He is saying that the temperature of the metal is between 1500-1900 F? Where does he get that figure from? I don't see any thermometers in the picture so he must have pulled that one from the same place he pulled his 4000lbs of explosives calculation.

While he is correct that aluminum would be runny at 1500-1900 F, It could be much lower than that and still be semi molten aluminum. It really doesn't make much sense that they would be dipping buckets made of steel into molten steel. Notice the lack of damage to the bucket in this 1900 degree envirnonment.


Someone esle once asked the following question, I saw no response to it so I thought I would repeat it.


Why is NIST unreliable when presented as evidence against demolition, but swallowed up when it can be twisted to support demolition?


Why do you guys accept NIST figures on anything? After all their conclusion was a gravity driven progressive collapse.

That this woman survived the impact is more than just incredible. There were others reported. Her clothes and hair are untainted.

About the molten hot steel. This is six weeks later. Its mere existence should send shivers down your spine. No matter how you look at it, it should not exist, yet satellite photos prove its existence.

The core columns were 54 inches by 22 inches by 5 inches thick. It would take some force to bring down 47 of them simultaneously. That force would provide the heat intensity to melt them, but not a fire 75 floors or more up.


The "official" story is absurd!

Originally posted by LeftBehind
It looks like theres more to the story than the oft-repeated black smoke=dying fires argument.

Not really. No one's ever denied the smoke starting to pick back up after WTC2's collapse, but I guess WTC1 and WTC2 fell for different reasons? WTC1 never got back to where it was, anyway, so it doesn't even matter.

Btw, have you backpeddled to not understanding how that works with hydrocarbon fires again? Because the way you worded that suggests you still don't get the argument there. It's seriously not complicated, dude, and there really aren't in any holes in it for you to pick out and cling to. All the fuel that was available there, was available the whole time.

Why is NIST unreliable when presented as evidence against demolition, but swallowed up when it can be twisted to support demolition?

This is a debate tactic, LB. Using the opposition's own sources to support your conclusion. It's nothing at all new.

[edit on 15-2-2006 by bsbray11]

About the molten hot steel. This is six weeks later. Its mere existence should send shivers down your spine. No matter how you look at it, it should not exist, yet satellite photos prove its existence.

The core columns were 54 inches by 22 inches by 5 inches thick. It would take some force to bring down 47 of them simultaneously. That force would provide the heat intensity to melt them, but not a fire 75 floors or more up.


The "official" story is absurd!

This is not to be ignored. Do not cite coal fires to me, there is no
way office contents maintained such a hot fire for so long without
the benefit of oxygen. Comparing oxygenated coal mines to the
basements of WTC 1 & 2 is ignorant.