WTC7 Fire Temperatures and effects on the East Floor System

[Thread split from https://www.metabunk.org/threads/cr...ssions-in-wtc7-report-uncovered.2332/page-12]

  • see above

yes? So you agree that fires caused the collapse right? yes or no?

It makes sense because the fires caused multiple failures within WTC7: "An initial local failure occurred at the lower floors (below Floor 14) of the building due to fire-induced floor failures, leading to buckling of a critical column ... Elevated temperatures in the floor elements led to thermal expansion, with or without thermal weakening and sagging, which resulted in failure of floor connections and/or buckling of floor beams. Sufficient floor component failures (connections and/or beams) resulted in at least one unsupported column over multiple floors at the lower floors. This column buckled and led to the initiation of global collapse." NIST NCSTAR 1-9, WTC Investigation 323

And WTC 7 isn't the only building with multi-floor failures due to fire, look at WTC 5: "
The uncontrolled fires resulted in complete burnout of most floors and partial collapse of four floors. The building was steel frame construction with field-bolted connections between floor beams and column tree assemblies. Failure of large sections of floor, in areas not damaged by falling debris from WTC 1, resulted from bolt tear-out at these connections as a result of the uncontrolled fires (Figure 8–14). Photographs of two recovered samples of floor beams (Figure 8–15) show how the field bolts tore out from the beam web weakened by the fires (McAllister 2002).
338 NIST NCSTAR 1-9, WTC Investigation"

So, you agree that fires caused the collapse right?
 
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Well, I believe I can understand a one word answer if you spell it out for me.
You agree that fires caused the collapse right? Yes or No?
I believe that NISTs collapse hypothesis, which involves thermal expansion of floor beams to the east of column 79 causing the failure of a girder that spanned columns 79 and 44 has critical errors and omissions. THAT is the topic of this thread. Mick has already started a new thread for you earlier when you were unable to address the content of this one. If I had any inclination to debate you on the question you ask, I would do it there. I suggest you pose the question there and see who responds to you, rather than derailing this thread further.
 
We are happy to discuss the information openly and honestly with anyone who is genuinely interested. I would also be interested in ways we could improve the information on the videos or make it easier to understand.

That's from your first post to this thread which you are worried about being "derailed." If you don't want to mislead people then you should start your videos by saying that the evidence is that fires caused the collapse. That would certainly improve your video because otherwise it could mislead people into not understanding that fires caused the collapse. But since you were unwilling to give a simple one word answer to my question if you agree that fires caused the collapse, it doesn't appear that you are "happy to discuss the information openly and honestly."

I also referred to a specific point in your video where I explained: "Tangled Webs NIST and WTC7 @ 4:31 the video deceptively asks people to compare WTC5 to WTC7 and it gives the false impression that no steel failed and collapsed within WTC5."

But you responded to that with this: "You are free to draw your own conclusions." So it doesn't look like you really are "interested in ways" you "could improve the information on the videos or make it easier to understand." Because if you were you could provide this info: "The collapse of WTC 1 caused damage to WTC 5 and started fires in it (McAllister 2002). The uncontrolled fires resulted in complete burnout of most floors and partial collapse of four floors. The building was steel frame construction with field-bolted connections between floor beams and column tree assemblies. Failure of large sections of floor, in areas not damaged by falling debris from WTC 1, resulted from bolt tear-out at these connections as a result of the uncontrolled fires (Figure 8–14). Photographs of two recovered samples of floor beams (Figure 8–15) show how the field bolts tore out from the beam web weakened by the fires (McAllister 2002).

338 NIST NCSTAR 1-9, WTC Investigation
And show these pictures:



see: https://www.metabunk.org/threads/critical-errors-and-omissions-in-wtc7-report-uncovered.2332/page-12#post-69630


 
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That's from your first post to this thread which you are worried about being "derailed." If you don't want to mislead people then you should start your videos by saying that the evidence is that fires caused the collapse. That would certainly improve your video because otherwise it could mislead people into not understanding that fires caused the collapse. But since you were unwilling to give a simple one word answer to my question if you agree that fires caused the collapse, it doesn't appear that you are "happy to discuss the information openly and honestly."
Wow.

It would never, ever, have occurred to me to ask the question: "You agree that fires caused the collapse right? Yes or No?", because the answer's so obviously Yes.

But there's an agenda for you. It will make you do strange things.

"Did NIST blame thermal expansion of floor beams to the east of column 79 for pushing the girder spanning columns 44 and 79 off its seat?"

Yes, they did. But they then did not claim that the girder being off its seat initiated collapse, nor was deception involved in their moments of confusion.

But these boys...

That the girder may have "walked" in its last moments due to floor expansion to the left of column 79, I have a "truther site" picture apparently confirming this:


Column 79 is the top internal column to the left of the rightmost corner.

As is plainly visible, the fire is progressing leftward and compounding column 79's problems by expanding the flooring to the left of it.

The colour coding (black) of the area denotes temperatures hot enough for steel to creep and sag.

Fancy making arguments about the effects of a long-running, intense, fire, yet never, ever, being able to say "yes" to that question...
 
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Jazzy. Never had you pegged as a kate bush fan, but there ya go. Unbelievable.
But there's an agenda for you. It will make you do strange things
Apparently so, for example, asking off topic questions in inappropriate threads. I wonder why.
Did NIST blame thermal expansion of floor beams to the east of column 79 for pushing the girder spanning columns 44 and 79 off its seat? Yes, they did
And there we have it. The initiating event.................
uh oh ....
they then did not claim that the girder being off its seat initiated collapse
ok, so it was the event which both preceded and facilitated the initiating event, which kind of makes it like....... oh, never mind.
nor was deception involved in their moments of confusion
I am comfortable if you would like to blame NISTs error on confusion, but they get paid not to be. It does in some way excuse yours though.
That the girder may have "walked" in its last moments due to floor expansion to the left of column 79, I have a "truther site" picture apparently confirming this:
Insert NISTs thermal image graphic whilst calling them truthers. And the award for most wrongness in one post 2013 goes to......Jazzy.
Column 79 is the top internal column to the left of the rightmost corner.As is plainly visible, the fire is progressing leftward and compounding column 79's problems by expanding the flooring to the left of it.
On the cartoon maybe, in the building, no.
The colour coding (black) of the area denotes temperatures hot enough for steel to creep and sag
Except that the scale only goes up to 575 and NIST say that beyond 600 is when steel sags.
Fancy making arguments about the effects of a long-running, intense, fire, yet never, ever, being able to say "yes" to that question...
Yes. Fancy that.
At least we agree on 2 things now Jazz. NIST say that fire induced thermal expansion caused beams to push the girder to the west at column 79 and eventually to fail, and that although this is not what you consider to be the initiating event, you agree that it happened before the girder failed and was therefor a prerequisite to failure in the manner NIST described.
Not being able to admit an event previous to and required for failure to initiate is in fact the initiating event. Fancy that.
 
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Wow.


As is plainly visible, the fire is progressing leftward and compounding column 79's problems by expanding the flooring to the left of it.

The colour coding (black) of the area denotes temperatures hot enough for steel to creep and sag.

Fancy making arguments about the effects of a long-running, intense, fire, yet never, ever, being able to say "yes" to that question...

1. What is the maximum temperature claimed for the steel in WTC 7?

2. Why don't the walls of self cleaning ovens "creep and sag"?

Overall, oven cleaning technology consists of three types: (1) self-cleaning pyrolytic ground coat,..The first reduces foodstuffs to ash with exposure to temperature between 900–1000 °F (482–538 °C)
http://en.wikipedia.org/wiki/Self_cleaning_oven
3. If there is another example of fires causing a 47+ story building to collapse in the same way as WTC7 could you point me to it? TIA
 
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Good question xenon, just thought I would check that with NIST.......
“Due to the effectiveness of the SFRM, the highest column temperatures in WTC 7 only reached an estimated 300°C (570°F), and only on the east side of the building did the floor beams reach or exceed about 600°C.” NCSTAR 1A, p 19

“The temperatures of some sections of the beams supporting Floors 8, 12, 13, and 14 exceeded 600°C.” NCSTAR 1A, p 48

whoops!

In their analysis, the took the beams we are talking about to 600 and the girder to 500. As Mick posted earlier, they also stated that the shear studs failed at a little over 100. Welcome to NIST land.
 
Unbelievable. Apparently so, for example, asking off topic questions in inappropriate threads. I wonder why.
Quote them and we will discuss it.

it was the event which both preceded and facilitated the initiating event
But not the only event.
"The displaced girder and other local fire-induced damage caused Floor 13 to collapse"
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I am comfortable if you would like to blame NISTs error on confusion, but they get paid not to be. It does in some way excuse yours though.
The confusion here is all yours. It isn't unusual for confused people to believe others to be confused. http://en.wikipedia.org/wiki/Dunning-Kruger

Insert NISTs thermal image graphic whilst calling them truthers. And the award for most wrongness in one post 2013 goes to......Jazzy.
http://dickatlee.com/issues/911/response_pm_0808.html

On the cartoon maybe, in the building, no.
A truther picked it. He also picked the image of a quiescent floor 12 because he didn't understand that insulated hot steel doesn't cool very quickly in a closed hot air environment. Air doesn't transfer heat easily.

And you, of course, (I'm getting used to you), would prefer to give the epithet "cartoon" to what Mr. Atlee was pleased to allow remain a "computed temperature distribution".

Except that the scale only goes up to 575 and NIST say that beyond 600 is when steel sags.
I believe they would have said the steel would be at half its room-temperature strength. (Actually 0.6 of its room-temperature strength.)
http://www.roymech.co.uk/Useful_Tables/Matter/Temperature_effects.html

Yes. Fancy that.
Yes. Fancy that.

At least we agree on 2 things now Jazz.
Are you sure? I can only count the last statement...

NIST say that fire induced thermal expansion caused beams to push the girder to the west at column 79 and eventually to fail, and that although this is not what you consider to be the initiating event, you agree that it happened before the girder failed and was therefor a prerequisite to failure in the manner NIST described. Not being able to admit an event previous to and required for failure to initiate is in fact the initiating event. Fancy that.
The initiating event was WTC1 striking WTC7. The essential precursor to girder failure was fire-induced damage, most likely the recent movement of the fire inboard and the other side of Column 79. Additional local fire-induced damage.

Okay, I have had a brainwave that may be a satisfactory compromise for the 'initiating event' controversy that has dogged this thread. In reverse order of occurrence. We could call the column buckling 'the initiating event'. We could call the girder failing the 'pre-initiating event' And we could then refer to the thermally expanding beams to the east the 'event required to facilitate the pre-intiating and initiating event'. Sound good?
"The displaced girder and other local fire-induced damage caused Floor 13 to collapse"
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1. What is the maximum temperature claimed for the steel in WTC 7?'
Whatever it was, you can check the above graph to discover how weak it made the steelwork.

2. Why don't the walls of self cleaning ovens "creep and sag"?
Because they never reach the air temperature inside the oven. The walls are ventilated on their other faces by cooling air. If they ever reached beyond 475 deg C, they certainly would do so. But that's hotter than any cooking oven.

with exposure to temperature between 900–1000 °F (482–538 °C)
Ah, interesting. OK, it's a brief run at creep temperatures. To avoid any risk of creep one would have to select a nickel/molybdenum alloy steel sheet to fabricate the oven interior. But creep is a function of time and temperature, so it may not be detectable over reasonably long periods of time even if you don't, and stick to plain carbon steel, and make the burn-off period as brief as possible.
Below 475 deg C the steel crystal grains are large enough to interlock and their molecules lacking the kinetic energy to break that locking. Above that point molecular energy allows the breaking of that 'lock' and the crystals to form new associations, and the alloy develops visco-elasticity.

3. If there is another example of fires causing a 47+ story building to collapse in the same way as WTC7 could you point me to it? TIA
No. That's life. You can wait all day for 47-story buildings collapsing due to fire, then you get three in a row...

“Due to the effectiveness of the SFRM, the highest column temperatures in WTC 7 only reached an estimated 300°C (570°F), and only on the east side of the building did the floor beams reach or exceed about 600°C.” NCSTAR 1A, p 19
“The temperatures of some sections of the beams supporting Floors 8, 12, 13, and 14 exceeded 600°C.” NCSTAR 1A, p 48
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whoops! In their analysis, the fire took the beams we are talking about to 600 and the girder to 500. As Mick posted earlier, they also stated that the shear studs failed at a little over 100. Welcome to NIST land.
But the east side was where the collapse occurred. (?) As in the cartoon.

I see you were unable to type the word fire. I put it in for you. Whoops indeed...
 
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The confusion here is all yours. It isn't unusual for confused people to believe others to be confused. http://en.wikipedia.org/wiki/Dunning-Kruger
You would say that, especially if you were confused.


Great, another pic of the 'fully involved in fire' wtc 7... more confused.com

Xenon said:
2. Why don't the walls of self cleaning ovens "creep and sag"?
Jazzy replied:
Because they never reach the air temperature inside the oven. The walls are ventilated on their other faces by cooling air. If they ever reached beyond 475 deg C, they certainly would do so. But that's hotter than any cooking oven.

I think you are talking about pizza ovens. :confused:

Anyway, no one else talks about air cooled ovens.

Alternatively, Jazzy muses/hypothesises:
Ah, interesting. OK, it's a brief run at creep temperatures. To avoid any risk of creep one would have to select a nickel/molybdenum alloy steel sheet to fabricate the oven interior. But creep is a function of time and temperature, so it may not be detectable over reasonably long periods of time even if you don't, and stick to plain carbon steel, and make the burn-off period as brief as possible.

But think again as for self cleaning ovens, the reason they do not 'creep' is because they have their own form of SFRM, in the form of an enamel/porcelain which protects the steel much as the steel in high rises are usually protected. The ovens are recommended to run on full power (500oC) for 3 to 4 hours with the door locked.

See: http://www.ovenu.co.uk/self-cleaning-ovens

http://www.wisegeek.com/what-is-a-self-cleaning-oven.htm
Because of the high temperatures which the self-cleaning oven reaches during the cleaning cycle, the oven is heavily insulated. This makes daily operation of the oven more efficient, because it does not lose as much heat as a conventional oven. However, the energy required to heat the self-cleaning oven to 900 degrees Fahrenheit (482 degrees Celsius) is immense. The balance between greater operating efficiency and periodic high energy demand probably puts a self-cleaning oven on par with a regular oven, in terms of overall energy consumption.
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Heavily insulated? Air cooled? Water cooled? Fully involved in fire? High temps? Low temps?



7hrs? 20mins? Who knows? Jazzy? Jackanory? :confused: Don't think so.
 
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The columns are still standing and without any lateral support around them...

Are you really suggesting that because a bit of floor gives way in a building that is hit by massive amounts of ejecta and is a raging inferno, that justifies a whole building collapsing in seconds virtually into its own footprint from hardly any fire?

And what makes you so sure that this little section collapsed as a result of the inferno, rather than impact?

http://911debunkers.blogspot.co.uk/2011/06/other-collapses-in-perspective_04.html

This issue in fact raises an interesting point. When one examines the list of other steel structures that have collapsed from fire that are often cited by debunkers, one thing immediately catches the eye: almost none of them are high-rise skyscrapers. The only building cited by debunkers that is a high-rise is the Windsor Tower in Madrid, and this building did not suffer a complete collapse. Jim Hoffman has examined the partial collapse of the Windsor Tower [4], and notes that all this incident proves is that a huge building-consuming fire, after burning for many hours, can produce the collapse of parts of a building with weak steel supports lacking fire protection, and that the collapse events that do occur are gradual and partial. Hoffman has also examined the McCormick Place roof collapse that is often cited by debunkers, and has shown why this structure is also not comparable to the WTC buildings [5]. Aside from the Windsor Tower, none of the other structures cited by debunkers are high-rises, and some of them are not even buildings.
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The columns are still standing and without any lateral support around them...

Are you really suggesting that because a bit of floor gives way in a building that is hit by massive amounts of ejecta and is a raging inferno, that justifies a whole building collapsing in seconds virtually into its own footprint from hardly any fire?

And what makes you so sure that this little section collapsed as a result of the inferno, rather than impact?

http://911debunkers.blogspot.co.uk/2011/06/other-collapses-in-perspective_04.html

This issue in fact raises an interesting point. When one examines the list of other steel structures that have collapsed from fire that are often cited by debunkers, one thing immediately catches the eye: almost none of them are high-rise skyscrapers. The only building cited by debunkers that is a high-rise is the Windsor Tower in Madrid, and this building did not suffer a complete collapse. Jim Hoffman has examined the partial collapse of the Windsor Tower [4], and notes that all this incident proves is that a huge building-consuming fire, after burning for many hours, can produce the collapse of parts of a building with weak steel supports lacking fire protection, and that the collapse events that do occur are gradual and partial. Hoffman has also examined the McCormick Place roof collapse that is often cited by debunkers, and has shown why this structure is also not comparable to the WTC buildings [5]. Aside from the Windsor Tower, none of the other structures cited by debunkers are high-rises, and some of them are not even buildings.
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Unfortunately the buildings that did not collapse are not really comparable either. Adam Taylor says:
http://911debunkers.blogspot.co.uk/2011/06/other-collapses-in-perspective_04.html
There are other skyscrapers that have been true infernos that can be considered comparable to the Towers and WTC7. For example, the One Meridian Plaza [7] and the First Interstate Bank [8], two skyscrapers that had huge fires, were core and perimeter structures like the Towers and Building 7, although not quite the same.
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But comparing the actual framing of Meridian with WTC7 shows they are not the same at all, as we discussed before:
https://www.metabunk.org/threads/sl...n-beam-structures-are-inherently-unsafe.1412/
 
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The ovens are recommended to run on full power (500oC) for 3 to 4 hours with the door locked.
Then they aren't made of carbon steel. You can be as rude as you like, but no mild, carbon, or cast steel fires or ovens can withstand sustained temperatures in the steel of over 475 deg C without slumping. They are all protected by brick, water or air, or even all three.

The columns are still standing and without any lateral support around them.
Why, so they are! Good thing they weren't in a fire-filled enclosure...

Are you really suggesting that because a bit of floor gives way in a building that is hit by massive amounts of ejecta and is a raging inferno, that justifies a whole building collapsing in seconds virtually into its own footprint from hardly any fire?
Depends what happens when it hits the floor beneath. You're another candidate for studying up on slender vertical column instability. Wiki it.

And what makes you so sure that this little section collapsed as a result of the inferno, rather than impact?
It isn't collapsed at all. We're looking at the same pictures?

almost none of them are high-rise skyscrapers. The only building cited by debunkers that is a high-rise is the Windsor Tower in Madrid, and this building did not suffer a complete collapse.
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The Windsor was r/c, with a steel exterior which collapsed.

Steel skyscrapers, Oxy. You wait for ages, and three turn up at once. The Plaza's not a skyscraper, although it is steel. It's just not carrying thirty-eight more floors, and those beams are relatively short. It's effectively much more redundant.
 
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There has never been 2 steel framed skyscrapers hit by planes and others hit by falling skyscrapers that also had totally uncontrolled fires.

The first time that someone is killed by falling space debris, will not mean that the debris was targeted at them, because 'it hadn't happened before'.
 
Then they aren't made of carbon steel. You can be as rude as you like, but no mild, carbon, or cast steel fires or ovens can withstand sustained temperatures in the steel of over 475 deg C without slumping. They are all protected by brick, water or air, or even all three.
Do you have any evidence of that or is it just your normal speculation?

Why, so they are! Good thing they weren't in a fire-filled enclosure...

Yep, that was really lucky they weren't in a massive inferno like below...



But then they were weren't they... and yet they still remain standing and the building remains standing and again you cannot show whether the small collapse area was caused by 'fire induced' or much more likely impact induced.

I mean think about it, are you and RP suggesting that the local collapse damage was caused by the same fire that did not cause the rest to collapse at some point? i.e. maybe some defective beams in a small cluster?

The Windsor was r/c, with a steel exterior which collapsed.

More bunk. Not only that but bunk that has been debunked ad nauseum on this very site and yet you still regurgitate it. You know full well the building did not 'collapse'. There was a partial collapse of the building in an area that had no fire protection on the extremely lightweight steel trusses that buckled; fires were intense and of 18 hours or so duration and there were structural faults due to it being refurbished at the time.

Same old same old.

Steel skyscrapers, Oxy. You wait for ages, and three turn up at once. The Plaza's not a skyscraper, although it is steel. It's just not carrying thirty-eight more floors, and those beams are relatively short. It's effectively much more redundant.

Yes, deny and reverse accepted fact that the taller the building, the less likely it is to collapse. Debunker 'engineers' with no experience of high rise buildings but a love of Newton's cradle? Gotta luv em :rolleyes:

 
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Unfortunately the buildings that did not collapse are not really comparable either.

Then why do 'debunkers' keep on citing any little steel shed or roof that partially collapses due to fire as proof that NIST is correct?

'Well the fact that this sheet steel shed filled with fluffy toys and chemicals partially collapsed proves that it is possible and if it had been a 50 storey high rise it would have had all that weight on it and would have been squished flat at freefall acceleration just like 7'.

This is not being impolite Mick, this is paraphrasing the debunker 'arguments' that some put up.
 
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... The ovens are recommended to run on full power (500oC) for 3 to 4 hours with the door locked.
...
I think you need to clarify or correct this as it may be causing some confusion.
Pretty sure that's a typo.
Can you quote that part, because the quote under that says 400-500c.
Also this from your link...

For an enamel to withstand up to 500 degrees centigrade, to be ‘self cleaning’, something has to be added.

This additive is glass. This then makes vitreous enamel…very heat resistant as it is applied to an oven interior at over 1200 degrees Celsius. (In some cases this coating can also be known as porcelain). This material is actually the same as a domestic toilet coating. (The only difference being that a toilet enamel is applied to clay rather than metal).
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So I think the self-cleaning oven avenue, while trivially informative, has nothing to do with this topic.
 
I think you need to clarify or correct this as it may be causing some confusion.
Pretty sure that's a typo.
Can you quote that part, because the quote under that says 400-500c.
Also this from your link...

For an enamel to withstand up to 500 degrees centigrade, to be ‘self cleaning’, something has to be added.

This additive is glass. This then makes vitreous enamel…very heat resistant as it is applied to an oven interior at over 1200 degrees Celsius. (In some cases this coating can also be known as porcelain). This material is actually the same as a domestic toilet coating. (The only difference being that a toilet enamel is applied to clay rather than metal).
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So I think the self-cleaning oven avenue, while trivially informative, has nothing to do with this topic.

Not sure what you are asking clarification on? The 500 degrees C I represented as 500oC is that it?

Right click disabled on that site so I kept it short but provided link. The 1200oC is in the manufacturing process. It is vitreous enamel which gives the high heat capacity.

I simply corrected Jazzy as he seemed to imagine that ovens had water or air cooling in them. I don't think that many people would appreciate that when they turned their ovens on they were then cooled by blowing air through them. Bit like the brake being automatically applied when you hit the gas on a car.

Perhaps some engineer may want to pinch this concept and design such a beast, a sports car that cannot exceed the speed limit but makes a lot of noise and burns a lot of gas? The non burning oven that bakes whilst it cools whilst it makes ice cubes? ideal for Arctic Rolls. Sounds good if you can sell it. Hope that clarifies ok.
 
The Windsor was r/c, with a steel exterior which collapsed.

Steel skyscrapers, Oxy. You wait for ages, and three turn up at once. The Plaza's not a skyscraper, although it is steel. It's just not carrying thirty-eight more floors, and those beams are relatively short. It's effectively much more redundant.

The Windsor "collapse" does not look like the WTC7 collapse.



Click here to see full resolution 1,169 x 2,048
http://upload.wikimedia.org/wikipedia/commons/a/a2/TorreWindsor1.JPG

And what about these:


The Beijing Mandarin Oriental Hotel Fire
After


On Nov. 15, 2010, a major fire broke out at a 28 story apartment building for teachers in the Jingan District of Shanghai. (Epoch Times photo archive)




After the Shanghai fire:



WTC7 fire:

 
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Not sure what you are asking clarification on? The 500 degrees C I represented as 500oC is that it?
.....
Yeah it looks like 5000.
...

I simply corrected Jazzy as he seemed to imagine that ovens had water or air cooling in them. ..
Okay I see it was xenon who suggested a link.

Nothing besides the temperatures are a few hundred degrees hotter than NIST says WTC7 steel was.
But the steel of the ovens is protected by ...
For an enamel to withstand up to 500 degrees centigrade, to be ‘self cleaning’, something has to be added.

This additive is glass. This then makes vitreous enamel…very heat resistant as it is applied to an oven interior at over 1200 degrees Celsius. (In some cases this coating can also be known as porcelain). This material is actually the same as a domestic toilet coating. (The only difference being that a toilet enamel is applied to clay rather than metal).
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so no it's not comparable.
 
Stick a 55' steel beam (supported only at the ends) in there for half an hour, see what happens.
What an SFRM coated thick steel beam that is an integral part of a concrete and steel floor?




In fact I would doubt that such an experiment hasn't been carried out at such places as Cardigan Fire Research etc.

Yes I would like to see the result of that. Not beyond the realms of scientific endeavor either, is it?

Bearing in mind that, as you well know, the SFRM would protect the beam in exactly the same way as the thin vitreous enamel coating protects the steel oven itself, I would fully expect the beam to survive easily... unless maybe it was made of aluminium.

http://www.fixya.com/support/t7912413-new_oven_melted_tin_foil_onto
With the older models of self-cleaning ovens one could put aluminum foil on the bottom tray of the oven, but with the newer models there is a warning (hidden in the last line) of your booklet for models of stoves where aluminum foil should 'not' be used! Even though print in small and many consumers are complaining regarding their stoves and melted aluminum stuck to the bottom tray of their oven (nothing will get it off) all manufacturer do 'not' cover this problem under warranty and thus, it will cost you $44 to buy a new tray. You unscrew the two screws to the bottom of the damaged tray of your oven and then install the new one and put back the screws. Letters of complaint should be written to the manufacturers to have them put this warning in clear bold print right on the front cover of the instruction brochure.
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This is a steel tray, covered in vitreous enamel. Not sure about the screws though.
 
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Bearing in mind that, as you well know, the SFRM would protect the beam in exactly the same way as the thin vitreous enamel coating protects the steel oven itself, I would fully expect the beam to survive easily... unless maybe it was made of aluminium.

Actually no, it's all about temperature gradients and thermal conductivity. The enamel of the stove slows down the heat leaving the (fixed temperature) hot oven so that it can dissipate from the steel, which maintains a much lower temperature than the inside surface of the enamel.

The SFRM performs the same role, but once the heat has got in, it has nowhere to go,


Anyway, there's really no need to guess about these things. There's lots of studies, tables of values, known coefficients, etc.
 
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Actually no, it's all about temperature gradients and thermal conductivity. The enamel of the stove slows down the heat leaving the (fixed temperature) hot oven so that it can dissipate from the steel, which maintains a much lower temperature than the inside surface of the enamel.

The SFRM performs the same role, but once the heat has got in, it has nowhere to go,


Anyway, there's really no need to guess about these things. There's lots of studies, tables of values, known coefficients, etc.
That makes no sense. Ovens are highly insulated to keep the heat in. If your square above was an oven it would be a fire and health hazard because it would be radiating heat out at such a rate that it would burn the surroundings and burn anyone who touched it. Think thermos flask.

An oven is a thermally insulated chamber used for the heating, baking or drying of a substance,[1] and most commonly used for cooking. Kilns and furnaces are special-purpose ovens, used in pottery and metalworking, respectively.
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Equally nonsensical is the idea that SFRM allows heat in and then holds the heat in. It would effectively be an oven and would be operating inversely to intention!

This would be a serious design flaw and much debated. The essence is that it protects the steel from being heated too quickly, i.e. if it is 500 C in the room, the steel will be around 200 to maybe 300 C and additional heat absorption will be slowed allowing heat to be sinking out to the connected steel surrounding material which is lower in temperature.

BTW, I researched Jazzy's theory of water cooled domestic ovens by searching "my oven has sprung a water leak" and got 0 hits. Guess they either do not exist or they are so reliable that they never spring a leak.:)
 
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That makes no sense. Ovens are highly insulated to keep the heat in. If your square above was an oven it would be a fire and health hazard because it would be radiating heat out at such a rate that it would burn the surroundings and burn anyone who touched it. Think thermos flask.

It's a case of diagram fail. The little arrows are meant to indicate a very low level of heat leakage. I just got carried away.



Equally nonsensical is the idea that SFRM allows heat in and then holds the heat in. It would effectively be an oven and would be operating inversely to intention!

SFRM (or any insulation) only SLOWS the heat flow. In the case of the oven, it comes out slowly. In the case of the girder it goes in slowly. The difference is that with the oven the exterior transfers heat to the outside world (the little arrows), so it stops getting hotter when that constant heat flow matches the intermittent heat input of the oven burner. With the girder you have a constant heat source, but once it has gone through the insulation, it's got less escape routes for that heat than an unshielded girder would.

The idea of SFRM is that it prevents enough heat getting to the steel for long enough that the fire goes out, and the heat goes elsewhere. But if the fire burns long enough, then the heat will get though.

Heat flow = K*A*T/L

K = the thermal conductivity (J/s m oC or BTU inch/hour foot2 oF)
A = the cross sectional area (meters2 or feet2)
T = temperature difference (oC or oF)
L = thickness (meters or inches)



upload_2013-10-10_15-9-46.png

Insulation has a low value for K, Steel has a high value. But heat is still constantly flowing through the insulation as long as one side is hotter than the other. In the case of the oven this is transferred to the outside world. In the case of the girder it's can only come out the ends of the girder.

As you can imagine, the calculation of these heat flowing in in complex steel frame building would be very involved, and need a computer for anything beyond the simplest case.
 
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BTW, I researched Jazzy's theory of water cooled domestic ovens by searching "my oven has sprung a water leak" and got 0 hits. Guess they either do not exist or they are so reliable that they never spring a leak.:)
I actually said: "no mild, carbon, or cast steel fires or ovens can withstand sustained temperatures in the steel of over 475 deg C without slumping. They are all protected by brick, water or air, or even all three".

I don't think the statements are the same. Do you?
 
Seems one salient point wrt ovens has been overlooked. The interior walls of an oven are under pretty much zero structural load.

Creep is a function of both temperature and load.

More to the point of course, the oven, be it gas, electric, wood or coal, is specifically designed to withstand temperatures expected to be encountered, over and over again.
This is accomplished by designing air flow, heat shielding, heat resistant materials and coatings etc. You are not, for instance , to burn coal in a stove designed for a wood fire.

If much heavier structural steel is not affected by typical office fire temperatures then 100 years of fire engineering is incorrect.

Oven temperatures is simply not a relevant point.
 
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A summary of temperatures from the NIST NCSTAR 1A paper:
http://www.nist.gov/customcf/get_pdf.cfm?pub_id=861610 (PDF)



"...Thus, WTC7 did not collapse due to fire-induced weakening of critical columns"

"...Temperatures did not exceed 300 °C (570 °F) in the core or perimeter columns in WTC7"

"...The thermal expansion of the WTC7 floor beams...occurred primarily at temperatures below ~750 °F"
 
WTC7 did not collapse due to fire-induced weakening of critical columns, temperatures did not exceed 300 °C (570 °F) in the core or perimeter columns in WTC7, the thermal expansion of the WTC7 floor beams occurred primarily at temperatures below ~750 °F"
That's very interesting.

jaydeehess said:
Oven temperatures is simply not a relevant point.
That's very interesting.
 
As I said, an oven interior, indeed the entire oven is never expected or designed to be under any load other than its own weight.

Stove/oven interiors are specifically designed with airflow, heat shielding and coatings, to withstand the temperatures reached.

Wood and coal stoves usually have firebrick lined fireboxes for the specific reason of insulating the steel from direct combustion heat. In addition instructions with a wood stove usually state unequivocally to use only wood in them, no coal, no liquid fuel accelerant, just wood.
Furthermore, wood stove chimney is rated to 1000 degrees C for one hour because chimney fires can reach this, from a mere hydrocarbon burn. That chimney must be replaced after a chimney fire has occured due to the distinct possibility of burn through. These are stainless steel construction.
 
Q. What safety certification has Model CF Chimney been tested to?
A. The Sentinel chimney has passed and completed all tests in accordance with the Standard CAN/ULC-S629 for 650°C factory-Built Chimneys. The temperatures used in this standard are: 1200°F (650°C) continuous (normal firing), 1700°F (925°C) one hour (overfiring) and 2100°F (1150°C) half-hour (creosote burn out) three times.
http://www.selkirkcorp.com/helpdesk/knowledgebase.aspx

I stand corrected on the standards.
Note a normal firing of a wood stove the chimney sees 650 C, but stoke it up a bit much and that rises to 925 C
A creosote chimney fire sees 1150 C

What's that about hydrocarbon burns being too cool to affect steel?
 
Its a subtle but relevent point. There a lot of examples of partial collapses of steel structural components. <<snipped for brevity. click link back to the other thread for the entire quote please>>
So implying that only a large all encompassing fire could stand a chance of bringing down a very uniquely constructed, asymmetric, long span open office space structure, is rather specious, IMO.
 
More bunk. Not only that but bunk that has been debunked ad nauseum on this very site and yet you still regurgitate it. You know full well the building did not 'collapse'. There was a partial collapse of the building in an area that had no fire protection on the extremely lightweight steel trusses that buckled; fires were intense and of 18 hours or so duration and there were structural faults due to it being refurbished at the time.

WTC 7 had NO active fire suppression system on 9/11.
The Windsor building DID have a concrete core which survived. It also did have the steel structure of several floors collapse. It is an example that steel structure can and does fail due to heat

NIST does not say that col 79 failed due to heat. They say it failed due to other failures. It was a step in the progression of collapse.

WTC 7 collapsed over a period of 16-20 seconds. First sign of a problem is the line of window breakage on the north face which not so incidentally is in line with the location of col 79. The east penthouse then falls inwards due to the roof opening up at the location of column 79.
At this point one would have a very difficult time claiming that a failure of column 79 was not integral to the collapse. Obviously then the time the collapse took must begin sometime prior to the window breakage on the north face.

NIST states that their sims showed that heat alone would not have caused a failure of columns the size of 79 and its neighbours. However, the sole, the only, known, and quite obvious, proximate cause of collapse are the fires taking place in WTC 7. Therefore NIST looked at other systems which if they failed could cause column 79 to later fail progressing from this earlier system failure.

So detectives,,,,,,, fires in the building,,,,,,,,,, column 79 failure must follow from another failure and not directly from heating of column,,,,,,, where do you look?

Well, I'd start with fires occurring close to column 79,,,,,,,, there it is on the 11,12,13th floors.

It seems some others wish to begin looking for a new proximate cause of initial failure and disregard any notion of progressive failure. .
 
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