Popular Mechanis & the fire in Madrid - Tilted Forum Project Discussion Community

Bookman · 02-14-2005, 12:20 PM

Popular Mechanics will have a piece in the March issuse which takes a stab at conspiracy theorist. I have yet to read it but the burning building issue is supposedly touched and fortified as truth.

Now the building in Madrid burned to up to 20 hours...and it remains erect.

What says the board?

Had one of the WTC towers fell over onto the street and buildings I would have eaten the cake...but the manner which they fell makes it hard to understand.

What say you? Different building...different circumstances?

Charlatan · 02-14-2005, 12:52 PM

The WTC was doused in jet fuel... the Madrid building was not.

Different building, different circumstances.

Bookman · 02-14-2005, 12:55 PM

Quote:

Originally Posted by Charlatan

The WTC was doused in jet fuel... the Madrid building was not.

Different building, different circumstances.

Cool but may I ask...what is the difference between jet fuel fires and non-jet fuel fires in regards to temperatures produced and duration.

Charlatan · 02-14-2005, 01:01 PM

Jet fuel, as far as I know, burns at a much higher temperature than say, the usual contents of an office building (carpets, furniture, drywall, paper, etc.)

I can't speak to the duration but the plane that went into the WTC were practically full of fuel. The stories I've read, suggest it was the heat from the fuel (and of course the weight of the building above) that caused the steel in the WTC's girders to eventually buckle.

I also understand that the WTC were designed to withstand plane collisions, but all things combined caused a collapse.

djtestudo · 02-14-2005, 01:33 PM

There is also the idea that the impact of the planes into the World Trade Center knocked off much of the fireproofing that otherwise would have protected the steel.

Definately different circumstances.

Redlemon · 02-14-2005, 01:37 PM

Quote:

Originally Posted by Bookman

Popular Mechanics will have a piece in the March issuse which takes a stab at conspiracy theorist. I have yet to read it but the burning building issue is supposedly touched and fortified as truth.

The article is now available online: PM: Debunking The 9/11 Myths - Mar. 2005 Cover Story.

Willravel · 02-14-2005, 01:44 PM

What is the melting point of steel (specifically the steel alloy used in common steel reinforcement for buildings)? What is the burining temperature of jet fuel?
Answer these questions, and you'll either get an conclusion, or you'll get more questions.

Seaver · 02-14-2005, 01:49 PM

Jet fuel burns MUCH hotter than a building fire would. The building fire would be wood, carpets, lamps.. many things that, while burn, do so very inefficiently. So, the intense heat warped and eventually made the steel support beams fail.

As far as falling sideways, the building was made to take a plane hit. It happened in the '40s to the Empire State Building, so knowledge of it could happen was known, and planned for, in advance.

What they didnt plan for was a plane loaded with enough fuel to fly over the ocean to crash into it. As stated the fireproofing, which is intended to insulate the steel from extreme heat, was blown away during the impact.

The building was built in a grid of squares of support beams. Newer buildings are built the same way but with X's to give added structural support with less weight (The Malasian towers for example). With the box pattern of the WTC, top-down collapse is what would happen if one or two layers of boxes were taken out. If it was supported with the X pattern it would twist, hopefully keeping just enough integrity to save it from complete collapse (though falling sideways is much more of a threat because of the twist).

Quote:

What is the melting point of steel (specifically the steel alloy used in common steel reinforcement for buildings)? What is the burining temperature of jet fuel?

I can tell you that jet fuel WILL cause damage. If you look at how jet engines work, the flame never even touches or comes close to the casing of the engine itself. They use very high pressures around the combustion chamber to keep the heat from touching the walls, and forcing the flames out the rear.

Redlemon · 02-14-2005, 01:55 PM

Quote:

Originally Posted by willravel

What is the melting point of steel (specifically the steel alloy used in common steel reinforcement for buildings)? What is the burining temperature of jet fuel?
Answer these questions, and you'll either get an conclusion, or you'll get more questions.

From the PM article:

Quote:

Jet fuel burns at 800° to 1500°F, not hot enough to melt steel (2750°F). However, 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--and that required exposure to much less heat. "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. 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."

Pacifier · 02-14-2005, 02:01 PM

Quote:

Originally Posted by willravel

What is the melting point of steel (specifically the steel alloy used in common steel reinforcement for buildings)? What is the burining temperature of jet fuel?

I get the conclusion that steel looses much of it stability at lower temperatures. It doesn't need to melt to collapse.

What are your conclusions?

Xell101 · 02-14-2005, 02:15 PM

Quote:

Originally Posted by Bookman

What says the board?

I say that the manner in which you're trying to compare them renders them dissimilar. Circumstances are too different to be comparable in the manner you suggest, and as such says nothing really.

Dyze · 02-14-2005, 03:00 PM

There is the thread in the Paranoia board where collapsing buildings are discussed. I saw an interview with a Spanish architect this morning and she said the building (in Madrid) might collapse due to structural insabilities that occured. The concrete frames started breaking.

Willravel · 02-14-2005, 03:53 PM

Quote:

Originally Posted by Pacifier

I get the conclusion that steel looses much of it stability at lower temperatures. It doesn't need to melt to collapse.

What are your conclusions?

Quote:

Jet fuel burns at 800° to 1500°F, not hot enough to melt steel (2750°F). However, 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--and that required exposure to much less heat. "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. 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."

Note: The following is conjecture and science about the North and South towers collapsing as it relates to questions abouyt the Madrid building.

The real question is: Why did the top story cave straight down, followed by the next to the top, followed by the third from the top, leading to the building collapsing at free fall speeds from metal beginning to bend just in the area with the jet fuel?

The jet fuel could have warped the structure in the area it was burning, and I'm sure that it did. But why did the top floor collapse down first without any collpase underneith it? It just seems odd to me. In order for it all to fall straight down into itself, the whole steel frame would have to be compromised almost at once.

What would have happened if the steel warped causeing the building to collapse: The planes hit, they burn very hot for hours and hours, possibly days. Eventually, the middle (middle meaning impact area) of the buildings becomes weak and a strong enough wind or the weight of the top of the buildings causes the middle to give. If it is wind, the top part of the building is blown away from the wind, crushing the back part of the building as it falls. If the weight of the top causes the middle to give, you'll see the top half of the building crunch down on the middle, then you see the building crumble as it all goes to the ground. Neither of those happened.

Also, the American Free Press reported pools of "molten steel" found at the base of the collapsed twin towers weeks after the collapse. That just doesn't fit with the jet fuel theory.

It is important to note that the theory about the melting frame collapse was just a theory put fourth by FEMA after the initial invesigation of the collapse. This theory has never been proven.

One theory is that there were thermite charges installed for some time before this happened in case the building was going to topple on it's side, crushing many buildings and possibly killing tens of thousands. The WTC was bombed before, so this was clearly something that could have beeen considered. The building was hit and it could have possibly collapsed, so they decided to "pull" the buildings (i.e. demolish them straight down, like a controled demolition). This would explain the manner of the falls, as well as the m,olten steel. Thermite burns at approximately 5,400 degrees (F), more than enough to liquify the structure. I've seen a video of thermite instantly liquifying a jeep engine.

Just one theory, I guess. It's up to you to figure out what you want to believe.

Bookman · 02-15-2005, 05:21 AM

Quote:

Originally Posted by willravel

Note: The following is conjecture and science about the North and South towers collapsing as it relates to questions abouyt the Madrid building.

The real question is: Why did the top story cave straight down, followed by the next to the top, followed by the third from the top, leading to the building collapsing at free fall speeds from metal beginning to bend just in the area with the jet fuel?

The jet fuel could have warped the structure in the area it was burning, and I'm sure that it did. But why did the top floor collapse down first without any collpase underneith it? It just seems odd to me. In order for it all to fall straight down into itself, the whole steel frame would have to be compromised almost at once.

What would have happened if the steel warped causeing the building to collapse: The planes hit, they burn very hot for hours and hours, possibly days. Eventually, the middle (middle meaning impact area) of the buildings becomes weak and a strong enough wind or the weight of the top of the buildings causes the middle to give. If it is wind, the top part of the building is blown away from the wind, crushing the back part of the building as it falls. If the weight of the top causes the middle to give, you'll see the top half of the building crunch down on the middle, then you see the building crumble as it all goes to the ground. Neither of those happened.

Also, the American Free Press reported pools of "molten steel" found at the base of the collapsed twin towers weeks after the collapse. That just doesn't fit with the jet fuel theory.

It is important to note that the theory about the melting frame collapse was just a theory put fourth by FEMA after the initial invesigation of the collapse. This theory has never been proven.

One theory is that there were thermite charges installed for some time before this happened in case the building was going to topple on it's side, crushing many buildings and possibly killing tens of thousands. The WTC was bombed before, so this was clearly something that could have beeen considered. The building was hit and it could have possibly collapsed, so they decided to "pull" the buildings (i.e. demolish them straight down, like a controled demolition). This would explain the manner of the falls, as well as the m,olten steel. Thermite burns at approximately 5,400 degrees (F), more than enough to liquify the structure. I've seen a video of thermite instantly liquifying a jeep engine.

Just one theory, I guess. It's up to you to figure out what you want to believe.

I have heard this before and it makes more sense than anything else I have heard. I posted this thread searching for a logical alternative but one has yet to emerge.

I too feel as though the south tower (2nd impact) the way it was struck on the South East side would have fallen over itself...not straight down. There was no fire on the SW, NW corners of the structure.

Ohhh well.

AngelicVampire · 02-15-2005, 07:00 AM

Remember that the Trade towers were built differently to most buildings, they were essentially two boxes connected by the floors.
-----------
| | | |
___ ___
| | | |
___ ____
| | | |

As the floors collapsed the actual forces on the steel supports increased (doubling the effective length of the support between crossbraces)... the more floors lost => greater chance of falling.

The Empire State building and the Madrid one are build more traditionally... Steel boxes stacked on each other rather than two boxes with a suspended floor...

Basically the towers were designed well... the actual plane impact was expected however the impact blew off a lot of the fire proofing and the fuel just burned down the place, it was a more susceptible building than traditional cosntruction though had benefits in other areas.

Bookman · 02-15-2005, 07:25 AM

Furthermore I must add that I have to doubt the fireeproofing claims because the evidence was carted off and sold immediately. There is no basis for the claims.

Yakk · 02-15-2005, 08:08 AM

Quote:

Also, the American Free Press reported pools of "molten steel" found at the base of the collapsed twin towers weeks after the collapse. That just doesn't fit with the jet fuel theory.

Laugh, weeks after the collapse? I'm pretty certain heat radiates faster than that. =p

Willravel · 02-15-2005, 10:16 AM

Relative to the 'temperature' argument, the imagery of the WTC does NOT reveal the aluminum siding of the WTC towers deforming. Thus, given the constant exposure - over time - to any escaping heat, it is difficult to imagine the fires being so hot as to cause either catastrophic or abrupt damage to the WTC vertical support structure. None of the images of the outer steel structure show the otherwise expected red-hot glow. All images show the outer shell mechanically destroyed, versus collapsing from thermal cause. Given the mechanics of the heat escape, the outer columns were the most vulnerable to heat damage. No matter what fire dynamics were going on within the building, the heat escape was almost exclusively - and constantly - around the outer columns. Hence, given both time and temperature, the outer columns should have been the structural 'weak-link.

Also, it should be mentioned that the FEMA report, the only real investigation with access to the collapsed remains, did not think the fuel was sufficient to initiate the structurel collapse.

From Chapter 2 of the FEMA report:

"The large quantity of jet fuel carried by each aircraft ignited upon impact into each building. A significant portion of this fuel was consumed immediately in the ensuing fireballs. The remaining fuel is believed either to have flowed down through the buildings or to have burned off within a few minutes of the aircraft impact.The heat produced by this burning jet fuel does not by itself appear to have been sufficient to initiate the structural collapses. However, as the burning jet fuel spread across several floors of the buildings, it ignited much of the buildings' contents, causing simultaneous fires across several floors of both buildings."

This suggests that the desks and paper and carpet and normal office furnature, ignited by the jet fuel fire, were able to melt the steel. That is basically impossible. I challenge you to melt a piece of aluminum (the melting point, and warping point, of which is substantially lower than steel) with a wood or plastic burning fire.

Take some normal paper, some wood, some plastic and some propane fuel. Douce the paper, wood, and plastic with the propane and light it in a safe burning area. Let it catch fire, and put a role of aluminum foil in it. Come back in a few hours. Do you think the aluminum would have melted? I can tell you the answer. The role in the center of the aluminum has melted, and there are singe marks on the outside, but the aluminum has not even begun to melt. It's physics.

These facts are not what surprise me. We've seen people do some pretty aweful stuff before. What really gets me is that no one asked these questions!

host · 02-15-2005, 12:45 PM

I guess no one here read my post on the "Rice....Memo"
thread. NIST is still conducting the most comprehensive
forensic investigation of the WTC towers. At their meeting in
Oct. 2004, the NIST investigators results so far do not support the jet fuel fire or heat from it, being the cause of the
collapse of either tower.

Quote:

<a href="http://fe.pennnet.com/Articles/Article_Display.cfm?Section=ARCHI&ARTICLE_ID=133237&VERSION_NUM=1">http://fe.pennnet.com/Articles/Article_Display.cfm?Section=ARCHI&ARTICLE_ID=133237&VERSION_NUM=1</a>
( Bill Manning Fire Engineering January, 2002)

Fire Engineering magazine, the 125-year old journal of record among America’s fire engineers and firefighters, recently blasted the investigation being conducted by the Federal Emergency Management Agency (FEMA) of the collapsed World Trade Center as a “a half-baked farce.”

Fire Engineering’s editor, William Manning, issued a “call to action” to America’s firefighters and fire engineers in the January issue asking them to contact their representatives in Congress and officials in Washington to demand a blue ribbon panel to thoroughly investigate the collapse of the World Trade Center structures.

<h2>The NIST Investigators so far, cannot find the reason why either WTC Tower collapsed !</h2>

Quote:

<a href="http://wtc.nist.gov/media/gallery.htm#recover">http://wtc.nist.gov/media/gallery.htm#recover Gallery of Recovered World Trade Center Steel at NIST</a>

<a href="http://www.nist.gov/public_affairs/ncstmin_oct19-20.htm">The National Construction Safety Team Advisory Committee
National Institute of Standards and Technology (WTC INVESTIGATION)
Minutes of October 19 - 20, 2004, Meeting - Gaithersburg, Maryland</a>

(Following is from the first Q&A...near the top of the web page)

Q: Referring to the column shortening in WTC 1, is the elastic strain reported at room temperature?
A: No. The values reported are for elevated temperature. The history is traced, including degradation of properties.

Q: For test 1 of the fire resistance tests of the floor systems at Underwriters Laboratories, you show unrestrained rating of one hour. Was that an analytical conclusion or a tested result?
A: We show in each case an unrestrained rating when we actually did a restrained test. What we are showing there is not the result of an actual unrestrained test, but the temperature criteria in the standard for a restrained test.
C: Right, one of the major significances of the series of these tests is that test 2 was an unrestrained test and showed superior performance.

Q: I want to ask about the floor performance. The way I understood your description of the collapse scenario, the behavior of the floor systems was not a central issue. Can you connect the floor results with that?
A: The results reinforce each other. The results of the fire test versus the load test support the finding that the floors were not a driving force in the collapse.

(Following Q&A is from the middle of the web page.....)
Q: In the absence of impact, fire only, burnout would have been achieved and the building would not have collapsed? Am I interpreting that correctly?
A: Yes. For the fires we have analyzed to date for floor systems with ¾ inch fireproofing in place, even with gaps observed in photographs, the floors would have deformed, but would not have initiated collapse.
A: We have looked at credible fires in an undamaged tower. Remember, for this scenario, there would not be broken windows to supply oxygen to fuel the fire. This is a working hypothesis and analyses remain to be completed.

Q: Regarding the findings for global analysis with impact damage, I want to make sure I’m interpreting the information correctly for floor 96 in WTC 1. At 600 seconds, there’s 23 inches of deflection on the trusses. When the fires move away, the trusses restore to 6 inches of deflection?
A: Yes. The 23 inches is next to the impact area.

C (NIST): Referring to the slide on global analysis without impact damage. You have a statement that burnout was likely prior to collapse. This infers that collapse would occur. You may want to change your wording to say burnout without collapse.
A: Agree.

Q: Do you have a complete run for the entire buildup of the tower?
A: We have completed the realistic case for WTC 1. The realistic case for WTC 2 is running and may be completed later today. We’ve also done the component analyses.

Q: Can you envision another set of conditions that gives the same observed failure mechanism?
A: We had to remove four to five floors to get global instability.
A: We looked at this very carefully. We could not find a way to make the building come down.

(The following Q&A is located near the bottom of the web page
Read the bold print paragraph. Recycling the steel was premature)

The last areas covered were a review of the findings from Project 3 and a description of the Investigation issue associated with Project 3. The issue deals with the use of "fire-resistant" steel in the United States, especially the appropriate measurement methods to characterize properties, and the codes in the United States, Japan, and Europe, which tend to encourage or discourage the use of such steels.

Q: I have a problem with the statement that the steel collected for the investigation is adequate. If I were doing an accident reconstruction, I would’ve been looking for core columns that were hit by the aircraft. It may be okay from a research perspective. It should not be stated that it is adequate from an investigation point of view.
A: It would have been nice to have, but may have been very hard to find. There is an issue of how the pieces hit would have survived and how they could be identified.
Q: If you go to the site, you look for pieces of the right size, etc. NIST never had the opportunity to do this type of search.
A: The Structural Engineers Association of New York (SEAoNY) started collecting steel in October of 2001. NIST was a member of that team. That team had a list of steel to look for. Some steel had disappeared and was recycled. NIST took over 8 months before the investigation began. We did not have reconstruction in mind. That would have been extremely expensive for us to do. We tried to get all grades of steel. We tried to get pieces from the impact zone, fire affected pieces, etc. If we had the authority, we would have been more aggressive.
Q: That’s what I’m saying. Looking down the road to future incidents, NIST should have the authority to preserve evidence useful for an investigation.
A: We’ll qualify that statement.

Q: The hypothesis is that core columns got above 600 ºC. It would be nice to have pieces of steel to support that hypothesis. You do have trusses from above the floors of impact?
A: None of the trusses could be identified as to location, only the truss seats that were considered part of the panels.

Q: Have you analyzed the truss seats?
A: Yes, but the steel for the truss seats was from various sources, so there was no baseline material for comparison purposes for metallography.

C: As John Barsom said, the statement is not accurate. The validity of the model question from yesterday speaks to this issue. I do not believe that we have enough forensic evidence. It may be okay to establish steel quality. There was no effort by the Building Performance Study team to systematically look at the steel.
C: The use of the term “adequate” needs to be revisited. There is no core column test to support the hypothesis. The floors came down, the slabs were pulverized. This was unprecedented. Exterior columns and core remained. The floors group will attack this finding.

C: With the low data points for the yield strength as shown on the slides, it does not appear to indicate that the steel meets the specifications. You need to flag the reasons for these outliers. Compression is a factor. Properties can change due to compression even if there is no deformation. This needs to be stated. Fire resistant steel claims by Japan are false. There is hardly any difference. The difference is in the modeling done in Japan. These steels would not perform better than U.S. materials. You need to concentrate on the performance of steel as it is tested—look at weldability, high-temperature chrome steels. Also, the cost of such steel may be a factor.

MSD · 02-15-2005, 09:43 PM

Quote:

Originally Posted by Bookman

Popular Mechanics will have a piece in the March issuse which takes a stab at conspiracy theorist. I have yet to read it but the burning building issue is supposedly touched and fortified as truth.

Now the building in Madrid burned to up to 20 hours...and it remains erect.

What says the board?

Had one of the WTC towers fell over onto the street and buildings I would have eaten the cake...but the manner which they fell makes it hard to understand.

What say you? Different building...different circumstances?

The WTC towers were essentially bulidings inside huge steel cages. The path of least resistance was straight down. Once one floor went, the impact hit the weakened floor below it, and the weight kept multiplying. Judging by the terribly inefficient security at our nation's airports and government buildings even after 9/11, it isn't entirely implausible to think that inadditino to plane crashes, car/truck bombs were in place and stockrooms near the impact sites had been filled with smuggled explosives. These could take advantage of weakened structural elements to sever the support to the top few floors and initiate a top-down collapse.

The same does not apply to building 7, which fell too perfectly to have been caused solely by damage casued by falling debris. This is less relevant to this discussion, however, as the building was unoccupied when it fell.

host · 02-15-2005, 10:48 PM

Quote:

Originally Posted by MrSelfDestruct

The WTC towers were essentially bulidings inside huge steel cages. The path of least resistance was straight down. Once one floor went, the impact hit the weakened floor below it, and the weight kept multiplying. Judging by the terribly inefficient security at our nation's airports and government buildings even after 9/11, it isn't entirely implausible to think that inadditino to plane crashes, car/truck bombs were in place and stockrooms near the impact sites had been filled with smuggled explosives. These could take advantage of weakened structural elements to sever the support to the top few floors and initiate a top-down collapse.

The same does not apply to building 7, which fell too perfectly to have been caused solely by damage casued by falling debris. This is less relevant to this discussion, however, as the building was unoccupied when it fell.

I'm quoting the NIST answers from the October 2004 update
posted on their website, and posted above by me...........

Quote:

Q: Referring to the column shortening in WTC 1, is the elastic strain reported at room temperature?
A: No. The values reported are for elevated temperature. The history is traced, including degradation of properties.

Q: For test 1 of the fire resistance tests of the floor systems at Underwriters Laboratories, you show unrestrained rating of one hour. Was that an analytical conclusion or a tested result?
A: We show in each case an unrestrained rating when we actually did a restrained test. What we are showing there is not the result of an actual unrestrained test, but the temperature criteria in the standard for a restrained test.
C: Right, one of the major significances of the series of these tests is that test 2 was an unrestrained test and showed superior performance.

Q: I want to ask about the floor performance. The way I understood your description of the collapse scenario, the behavior of the floor systems was not a central issue. Can you connect the floor results with that?
A: The results reinforce each other. The results of the fire test versus the load test support the finding that the floors were not a driving force in the collapse.

(Following Q&A is from the middle of the web page.....)
Q: In the absence of impact, fire only, burnout would have been achieved and the building would not have collapsed? Am I interpreting that correctly?
A: Yes. For the fires we have analyzed to date for floor systems with ¾ inch fireproofing in place, even with gaps observed in photographs, the floors would have deformed, but would not have initiated collapse.
A: We have looked at credible fires in an undamaged tower. Remember, for this scenario, there would not be broken windows to supply oxygen to fuel the fire. This is a working hypothesis and analyses remain to be completed.

Q: Regarding the findings for global analysis with impact damage, I want to make sure I’m interpreting the information correctly for floor 96 in WTC 1. At 600 seconds, there’s 23 inches of deflection on the trusses. When the fires move away, the trusses restore to 6 inches of deflection?
A: Yes. The 23 inches is next to the impact area.

C (NIST): Referring to the slide on global analysis without impact damage. You have a statement that burnout was likely prior to collapse. This infers that collapse would occur. You may want to change your wording to say burnout without collapse.
A: Agree.

Q: Do you have a complete run for the entire buildup of the tower?
A: We have completed the realistic case for WTC 1. The realistic case for WTC 2 is running and may be completed later today. We’ve also done the component analyses.

Q: Can you envision another set of conditions that gives the same observed failure mechanism?
A: We had to remove four to five floors to get global instability.
A: We looked at this very carefully. We could not find a way to make the building come down.

MrSelfDestruct....PM me if you feel like disclosing where you
are in CT.....I lived there for 37 years......last location was
a south central shore town....I miss LI Sound.

02-14-2005, 12:20 PM	#1 (permalink)
Bookman Insane	Popular Mechanis & the fire in Madrid Popular Mechanics will have a piece in the March issuse which takes a stab at conspiracy theorist. I have yet to read it but the burning building issue is supposedly touched and fortified as truth. Now the building in Madrid burned to up to 20 hours...and it remains erect. What says the board? Had one of the WTC towers fell over onto the street and buildings I would have eaten the cake...but the manner which they fell makes it hard to understand. What say you? Different building...different circumstances?

02-14-2005, 12:52 PM	#2 (permalink)
Charlatan Getting it. Super Moderator Location: Lion City	The WTC was doused in jet fuel... the Madrid building was not. Different building, different circumstances. __________________ "My hands are on fire. Hands are on fire. Ain't got no more time for all you charlatans and liars." - Old Man Luedecke

02-14-2005, 01:01 PM	#4 (permalink)
Charlatan Getting it. Super Moderator Location: Lion City	Jet fuel, as far as I know, burns at a much higher temperature than say, the usual contents of an office building (carpets, furniture, drywall, paper, etc.) I can't speak to the duration but the plane that went into the WTC were practically full of fuel. The stories I've read, suggest it was the heat from the fuel (and of course the weight of the building above) that caused the steel in the WTC's girders to eventually buckle. I also understand that the WTC were designed to withstand plane collisions, but all things combined caused a collapse. __________________ "My hands are on fire. Hands are on fire. Ain't got no more time for all you charlatans and liars." - Old Man Luedecke

02-14-2005, 01:33 PM	#5 (permalink)
djtestudo Baltimoron Location: Beeeeeautiful Bel Air, MD	There is also the idea that the impact of the planes into the World Trade Center knocked off much of the fireproofing that otherwise would have protected the steel. Definately different circumstances. __________________ "Final thought: I just rented Michael Moore's Bowling for Columbine. Frankly, it was the worst sports movie I've ever seen." --Peter Schmuck, The (Baltimore) Sun

02-14-2005, 03:00 PM	#12 (permalink)
Dyze Crazy	There is the thread in the Paranoia board where collapsing buildings are discussed. I saw an interview with a Spanish architect this morning and she said the building (in Madrid) might collapse due to structural insabilities that occured. The concrete frames started breaking. __________________ Knowing is not enough, we must apply. Willing is not enough, we must do.

02-14-2005, 01:44 PM	#7 (permalink)
Willravel ... a sort of licensed troubleshooter.	What is the melting point of steel (specifically the steel alloy used in common steel reinforcement for buildings)? What is the burining temperature of jet fuel? Answer these questions, and you'll either get an conclusion, or you'll get more questions.

02-15-2005, 07:00 AM	#15 (permalink)
AngelicVampire Insane	Remember that the Trade towers were built differently to most buildings, they were essentially two boxes connected by the floors. ----------- \| \| \| \| ___ ___ \| \| \| \| ___ ____ \| \| \| \| As the floors collapsed the actual forces on the steel supports increased (doubling the effective length of the support between crossbraces)... the more floors lost => greater chance of falling. The Empire State building and the Madrid one are build more traditionally... Steel boxes stacked on each other rather than two boxes with a suspended floor... Basically the towers were designed well... the actual plane impact was expected however the impact blew off a lot of the fire proofing and the fuel just burned down the place, it was a more susceptible building than traditional cosntruction though had benefits in other areas.

02-15-2005, 07:25 AM	#16 (permalink)
Bookman Insane	Furthermore I must add that I have to doubt the fireeproofing claims because the evidence was carted off and sold immediately. There is no basis for the claims.

02-15-2005, 10:16 AM	#18 (permalink)
Willravel ... a sort of licensed troubleshooter.	Relative to the 'temperature' argument, the imagery of the WTC does NOT reveal the aluminum siding of the WTC towers deforming. Thus, given the constant exposure - over time - to any escaping heat, it is difficult to imagine the fires being so hot as to cause either catastrophic or abrupt damage to the WTC vertical support structure. None of the images of the outer steel structure show the otherwise expected red-hot glow. All images show the outer shell mechanically destroyed, versus collapsing from thermal cause. Given the mechanics of the heat escape, the outer columns were the most vulnerable to heat damage. No matter what fire dynamics were going on within the building, the heat escape was almost exclusively - and constantly - around the outer columns. Hence, given both time and temperature, the outer columns should have been the structural 'weak-link. Also, it should be mentioned that the FEMA report, the only real investigation with access to the collapsed remains, did not think the fuel was sufficient to initiate the structurel collapse. From Chapter 2 of the FEMA report: "The large quantity of jet fuel carried by each aircraft ignited upon impact into each building. A significant portion of this fuel was consumed immediately in the ensuing fireballs. The remaining fuel is believed either to have flowed down through the buildings or to have burned off within a few minutes of the aircraft impact.The heat produced by this burning jet fuel does not by itself appear to have been sufficient to initiate the structural collapses. However, as the burning jet fuel spread across several floors of the buildings, it ignited much of the buildings' contents, causing simultaneous fires across several floors of both buildings." This suggests that the desks and paper and carpet and normal office furnature, ignited by the jet fuel fire, were able to melt the steel. That is basically impossible. I challenge you to melt a piece of aluminum (the melting point, and warping point, of which is substantially lower than steel) with a wood or plastic burning fire. Take some normal paper, some wood, some plastic and some propane fuel. Douce the paper, wood, and plastic with the propane and light it in a safe burning area. Let it catch fire, and put a role of aluminum foil in it. Come back in a few hours. Do you think the aluminum would have melted? I can tell you the answer. The role in the center of the aluminum has melted, and there are singe marks on the outside, but the aluminum has not even begun to melt. It's physics. These facts are not what surprise me. We've seen people do some pretty aweful stuff before. What really gets me is that no one asked these questions!