WTC Metal Fatigue. How Did Building 7 Fall?

[Noddy]

Building 7 was hit by no aircraft or debris. It had several small fires and amazingly collapsed in symmetrical fashion at free fall speeds.

We saw in Madrid a building burn at intense levels for MANY hours but not collapse.

Is there any scientific explanation for such a catastrophic structural failure in a largely steel building?

I am concerned. Friends and family work in similar structures. It seems strange that I see little debate on such an important subject...a modern steel structure completely collapsing after a few small fires ignite.

I have read the official reports. They summize they cannot explain the collapse.

Does anyone know of any other reports that could shed some light on such an important subject? Does anyone here have a view on how steel could collapse in such a sudden, catastrophic manner?

 

[FredGarvin]

Oh boy. Here we go AGAIN.

Building 7 was hit by no aircraft or debris.

That is your first error. WTC 7 got hit by quite a bit of debris by towers 1 and 2.

We saw in Madrid a building burn at intense levels for MANY hours but not collapse.

So what does that have to do with WTC7? Are the two buildings even remotely similar in construction? Did it have working fire supression? WTC7 did not have working sprinklers due to a water main break. WTC7 also had critical structural members on floors 5 and 6 which were on fire. They also had the possibility of 20,000 gallons of diesel fuel feeding the fire.

I have read the official reports. They summize they cannot explain the collapse.

Have you read them? Did you understand them? If you are expecting answers with 100% certainty, you're not going to find one. Even the report I cite below recommends getting more data. Personally, going into a pile of rubble and determining how it fell is pretty amazing stuff. Unless you are in the position to do the same, I would suggest dropping the conspiracy theories until real proof is presented.

I don't consider 7 hours on fire sudden.

WTC 7 summary:
http://www.house.gov/science/hot/wtc/wtc-report/WTC_ch5.pdf

 

[LocktnLoaded]

Sorry I don't have a clue to how it collapsed the way it did, I've seen the video and it seriously looks like a controlled demolition, and I find that it's also strange that the 9/11 commision report did not even mention its collapse, or how it was possible.

 

[russ_watters]

I don't see what this has to do with metal fatigue, but anyway, this isn't something to be concerned about. If you really posted this thread out of concern over the possibility of other buildings collapsing on your friends, just remember, 7 hours is plenty of time to evacuate a building. Also, as Fred noted, the situation on 9/11 was highly unique.

 

[LocktnLoaded]

I have to disagree with Freds contention, (They also had the possibility of 20,000 gallons of diesel fuel feeding the fire.), who evidently hasn't seen the video that shows only two small fires before the collapse.

 

[FredGarvin]

I have to disagree with Freds contention, (They also had the possibility of 20,000 gallons of diesel fuel feeding the fire.), who evidently hasn't seen the video that shows only two small fires before the collapse.

Two small fires? Are you kidding me? I suggest you look at the report I posted a link to. There were quite a lot of fires burning on multiple floors with photographs.

pg 5-20 and 5-21: According to fire service personnel, fires were initially seen to be present on non-contiguous floors on the south side of WTC7 at approximately floors 6,7,8,10,11 and 19. The presence of fire and smoke on lower floors is also confirmed by the early television news coverage of WTC7, which indicated light color smoke rising from the lower floors of WTC7.

pg 5-21: Another photograph (Figure 5-18) of the skyline at 3:25 p.m., taken from the southwest, shows a large volume of smoke coming from all but the lowest levels of WTC7, where white smoke is eminating.

I also recommend you look at page 5-14 which outlines where in the building the fuel tanks for the back up generator systems were located. Only two tanks were located below ground. The rest were inside the building.

 

[russ_watters]

Two small fires? Are you kidding me? I suggest you look at the report I posted a link to. There were quite a lot of fires burning on multiple floors with photographs.

One thing people tend to forget about this is that the damage/fires in this case would not be as visible from the outside as people tend to expect.

Typically a fire is confined to a single floor and spreads to engulf the entire floor. That ends up looking like a "ring of fire" encircling the building. It takes a long, long time for such a fire to spread beyond the floor it starts on, but they are very impressive looking from the outside.

With WTC7, a lot of the pictures we see are of the side of the building that appeared relatively undamaged, while most of the fire/damage stayed on the other side of the building.

To some extent we really have to take the word of the firefighters who went in there and reported back that the building was in danger of collapse. They were inside. That almost makes the issue/resolution trivially self-evident: the fire fighters were afraid the fires would make it collapse - it collapsed - so the firefighters were probably right that it collapsed due to the fires.

 

[FredGarvin]

To some extent we really have to take the word of the firefighters who went in there and reported back that the building was in danger of collapse. They were inside. That almost makes the issue/resolution trivially self-evident: the fire fighters were afraid the fires would make it collapse - it collapsed - so the firefighters were probably right that it collapsed due to the fires.

I agree. The sad thing is that without 100% undeniable proof of what happened, interviews, photos and the like will always be questioned and fuel the conspiracy theorists.

 

[LocktnLoaded]

Wheres the link to this, and does it have links to your resource material. pg 5-20 and 5-21: According to fire service personnel, fires were initially seen to be present on non-contiguous floors on the south side of WTC7 at approximately floors 6,7,8,10,11 and 19. The presence of fire and smoke on lower floors is also confirmed by the early television news coverage of WTC7, which indicated light color smoke rising from the lower floors of WTC7.

 

[russ_watters]

Wheres the link to this, and does it have links to your resource material.

The bottom of post 2. That's the official report on its collapse.

 

[Noddy]

Building 7

G'Day Russ.

I worked for many years in "Fire Assay"...that is melting stuff in 1300c firnaces to see what was in them.

I also transferred into Shotfiring where I got to blow things up on a regular basis including packing plastic type explosive - "Power Gel" - around objects to blast them apart and make the way clear for large vehicles.

You soon learn the power of explosives as you can make them cut like a knife through objects of any sought.

Anyway...i watched that building fall. What can't be explained to me is it's symmetrical collapse. How could metal POSSIBLY fail in such a symmetrical fashion? I note that the central core went first as is evident by the video and the "penthous" failing first.

I know what heat does Russ. I know that a few fires, which were only just visible, whether fueled by a bit of deisel or not, are EXTREMELY unlikely to "weaken" support core structures to that extent in THAT short a time.

Large metal beams can dissapait heat easily. If it was that easy to "melt" or "weaken" metal to such a point then I guess we can dispense with the well insulated metal furnaces i used to use and the high pressure natural gas feed and just chuck some deisel on top of the samples I used to melt.

Please keep your arrogant and paternalistic tone to yourself.

You find the fact that finding out how such a large metal structure collapsed...is somehow a waste of time and bothersome?

I guess you must work at NASA as they seem to have the same attitude when it comes to probing into the causes of things.

I am interested in hearing from people involved in the metal trade, particularly those involved in fatuige testing metal materials...if they come here.

I appreciate your input Russ but can you please bottle the paternalistic tone.

I want to know how that building collapsed. We saw other buildings TRASHED by WTC debris which were kind enough to remain standing and indeed retain there structural integrity enough to be rebuilt.

I know what the heat requirements are to weaken metal and join points.

And as for your claim that the reports mentioned 5-6 floors had CRITICAL structural members which were on fire, this in NO way explains the symetrical and catastrophic collapse of WTC 7. In NO WAY does this explain it.

In fact they can't explain it Russ. Thats the point. All your arguments are null and void as in the end the reports DO NOT claim to know the cause.

"They" cannot help. Can anyone else here?

 

[yourdadonapogostick]

http://www.propagandamatrix.com/articles/july2005/060705controlleddemolition.htm

 

[Noddy]

Building 7 & Firefighter reports.

Dear Russ,

This is off point but it is one you have made with some certainty.

You claim fire fighters in Building 7 reported that the fires were such that the building was in danger of collapsing.

Fine.

You seem to trust the opinion of firefighters.

In that case we seem to have a problem of sorts with your logic.

It is WELL reported and ON THE RECORD that firefighters in the towers reported small fires that would be easily contained and extinguished. It is also ON THE RECORD that not ONE firefighter believed there was ANY chance of those buildings collapsing. Minutes later the first of the Towers suffered a catastrophic collapse.

Which will it be?

Or will you simply be picking and choosing your line of thought to suit yourself?

And by the way...i do not appreciate being accused of being a "whacky conspiricy theorist" because I WANT TO KNOW how those buildings collapsed. ESPECIALLY BUILDING 7.

And why we're on the subject of fire fighters opinions, you are aware of the fact the the premiere firefighting magazine called the report..."a half baked farce".

I demand answers. Thats why I'm here.

And here I edit again...to question your logic...what exactly was burning in those buildings to make large steel girders buckle? To make bolts the size of my fist and weld joints split and crack? Carpet? Wooden furniture? Deisel?

Diesel is a relatively LOW volatility fuel but if it were feeding those fires we would have seen a fire ball in short order...agreed? Or is there some other laws of the Universe you wish to postulate?

As for Building 7 being PELTED by debris...please direct me to the photographs and video showing large scale structural damage to Building 7?

I don't know what you rqualifacations are Russ but mine are pretty good. Especially the qualifacation as a free thinking human with an expansive frontal lobe able to spot "over intellectualized bulldust" when I see it.

 

[Astronuc]

WTC 7 collapsed on September 11, 2001, at 5:20 p.m. There were no known casualties due to this collapse. The performance of WTC 7 is of significant interest because it appears the collapse was due primarily to fire, rather than any impact damage from the collapsing towers. Prior to September 11, 2001, there was little, if any, record of fire-induced collapse of large fire-protected steel buildings.

At 10:29 a.m., WTC 1 (the north tower) collapsed, sending its debris into the streets below. The extent and severity of the resulting damage to WTC 7 are currently unknown. However, from photographic evidence and eyewitness accounts discussed below, it was assumed that the south side of the building was damaged to some degree and that fires in WTC 7 started at approximately this time.

It would appear that fires burned for 7 hrs - not exactly a short time. The center of the building has numerous elevators and stairwells, so those could provide some central cavity for fire propagation and perhaps air to feed the fire.

I think it is also important to realize that prior to the event, there is apparently not record of a collapse of a steel building due to fire, so I doubt there is much research on the subject.

Pages 5-15 and 5-16 discuss some issues related to fuel oil for emergency generators. At the time of the report some tanks had not been retrieved.

It is important to note that floors 5 through 7 contained structural elements that were important to supporting the structure of the overall building. The 5th and 7th floors were diaphragm floors that contained transfer girders and trusses. These floors transferred loads from the upper floors to the structural members and foundation system that was built prior to the WTC 7 office tower. Fire damage in the 5th to 7th floors of the building could, therefore, have damaged essential structural elements.

page 5-23

and -

According to fire service personnel, fires were initially seen to be present on non-contiguous floors on the south side of WTC 7 at approximately floors 6, 7, 8, 10, 11, and 19.

page 5-20.

see then - section - 5.5.4 Sequence of WTC 7 Collapse page

Presumably with weakened core structure, the building started to collapse, falling mass from above caused a chain reaction (similar to WTC 1 and 2) which caused collapse of lower floors. The collapse of the penthouses indicates loss of core integrity.

Regarding -

As for Building 7 being PELTED by debris...please direct me to the photographs and video showing large scale structural damage to Building 7?

Figure 5-14 is an aerial photograph that shows the debris clouds spreading around WTC 7 just after the collapse of WTC 1. Figure 5-15 is a photograph of WTC 1 debris between the west elevation of WTC 7 and the Verizon building. Figure 5-12(B) shows a plan-view diagram approximating the extent of this debris just after the collapse of WTC 1.

It does not appear that the collapse of WTC 1 affected the roof, or the east, west, and north elevations of WTC 7 in any significant way. However, there was damage to the southwest corner of WTC 7 at approximately floors 8 to 20, 24, 25, and 39 to 46, as shown in Figure 5-16, a photograph taken from West Street.

This seems inconclusive at best.

Diesel fuel may have fed some of the fire, but it is not volatile, and it may have been released gradually. So it does not seem necessary to have a fireball.

 

[Pengwuino]

why do people trivialize these things so much?

Is there anyone who really thinks hte US government, with possibly 2 billion people watching on, would demolish a building in plane sight and lie?

 

[Astronuc]

why do people trivialize these things so much?

Is there anyone who really thinks hte US government, with possibly 2 billion people watching on, would demolish a building in plane sight and lie?

I don't think the OP was asking or inferring that anyone intentionally brought down WTC 7 after the fact.

The OP seems to ask how - given relatively small fires - the building could have collapsed so symmetrically. That is also what experienced structural engineers have asked, and probably many are still trying to understand what happened.

Clearly the buildings in question experienced situations beyond design. And in fact, one will find that the 'normal' design process is often deficient in addressing beyond design situations, which are considered quite rare.

I should have pointed out that the buckling of the building coincided with the longest members, and that is where one would expect it to fail - i.e. no surprise there.

The other point - structural analysis, and particularly predictive analysis is very complex. There are very few who do it very well.

 

[FredGarvin]

I worked for many years in "Fire Assay"...that is melting stuff in 1300c firnaces to see what was in them.

I also transferred into Shotfiring where I got to blow things up on a regular basis including packing plastic type explosive - "Power Gel" - around objects to blast them apart and make the way clear for large vehicles.

You soon learn the power of explosives as you can make them cut like a knife through objects of any sought.

BORING! Please tell us what your background is in the structural mechanics of buildings is. Please tell us that you have studied the layout of all of the support structure to that building. Please tell us that you have some professional credentials at all. I look at the moon and stars every night. I guess that means I have 30+ years experience as an astrophysicist or astronamer.

Anyway...i watched that building fall. What can't be explained to me is it's symmetrical collapse. How could metal POSSIBLY fail in such a symmetrical fashion? I note that the central core went first as is evident by the video and the "penthous" failing first.

Ok...you say you understand about how the central core of the building gave way first, but you don't understand how it happened symmetrically. Since you are using intuition and nothing else, I will too. Doesn't it seem intuitive that if the center of something gives that the remainder will give at the same time? To me it makes sense, but I am not a structural engineer.

I know what heat does Russ. I know that a few fires, which were only just visible, whether fueled by a bit of deisel or not, are EXTREMELY unlikely to "weaken" support core structures to that extent in THAT short a time.

I think we've beaten this horse to death. If you consider 20,000+ gallons a bit of diesel, then ok. However, the report shows multiple pictures and eyewitness accounts of more than a just a few in number and burned for more than 7 hours. Please debate this further based on your video clip you keep mentioning. If this video is all you have to go on, your one leg is shaky to say the least.

Large metal beams can dissapait heat easily. If it was that easy to "melt" or "weaken" metal to such a point then I guess we can dispense with the well insulated metal furnaces i used to use and the high pressure natural gas feed and just chuck some deisel on top of the samples I used to melt.

Do your furnaces help to dissipate the load of an entire building? Please show me a free body diagram showing the forces on a building support and then the ones a furnace has to encounter. This is a complete apples and oranges comparisson.

Please keep your arrogant and paternalistic tone to yourself.

The only arrogance I see is people that come up with conspiracy theories based on zero experience in a field, with no feel for the magnitude of what happened and their own intuition that is baseless, but yet feel the need to question and arm chair quarterback the experts doing the actual work.

You find the fact that finding out how such a large metal structure collapsed...is somehow a waste of time and bothersome?

That was not said anywhere. Please cite where anything remotely close to that was said. What was said was that the information is sketchy at best and that more work needs to be done.

I guess you must work at NASA as they seem to have the same attitude when it comes to probing into the causes of things.

Resorting to emotional responses instead of the facts presented is not a way to make yourself seem credible.

I am interested in hearing from people involved in the metal trade, particularly those involved in fatuige testing metal materials...if they come here.

I just posted a link to the official report which was created by just such a group of people.

I want to know how that building collapsed.

You are not alone in wanting a 100% positive answer.

We saw other buildings TRASHED by WTC debris which were kind enough to remain standing and indeed retain there structural integrity enough to be rebuilt.

So if one other building made it, then all of the others should have too?

I know what the heat requirements are to weaken metal and join points.

And as for your claim that the reports mentioned 5-6 floors had CRITICAL structural members which were on fire, this in NO way explains the symetrical and catastrophic collapse of WTC 7. In NO WAY does this explain it.

You've thrown down the gauntlet here. Please provide your data and reasoning behind this statement of "fact." Please come down from the mountain top and explain why all of the experts that were on site, that collected data and that know that building are wrong.

In fact they can't explain it Russ. Thats the point. All your arguments are null and void as in the end the reports DO NOT claim to know the cause.

They have provided the most probable causes. Theirs is an educated guess. That is understood. That does not make the argument void. The official release has data and eyewitnesses to back them up. What do you have?

There are two DRASTIC things flawed with yours and other's line of reasoning:

1) You have based all of your assumptions on seat of the pants guess work and a single video clip.

2) WHY? Why would they deliberately destroy the building? You have no solid theory as to why they would do such a thing.

 

[russ_watters]

Fred covered most of it, but a few points:

Anyway...i watched that building fall. What can't be explained to me is it's symmetrical collapse. How could metal POSSIBLY fail in such a symmetrical fashion? I note that the central core went first as is evident by the video and the "penthous" failing first.

It wasn't quite symmetrical: the report discusses/shows a "kink" in the building indicating a failed structural member initiated the collapse. After the collapse begins, however, and except for that little "kink", symmetrically is the only way such a building can collapse.

I know what heat does Russ. I know that a few fires, which were only just visible, whether fueled by a bit of deisel or not, are EXTREMELY unlikely to "weaken" support core structures to that extent in THAT short a time.

Ok... well, engineers and firefighters disagree with you. It is, of course, your prerogative to form your own conclusions, but despite the fact that I'm a mechanical engineer, I don't consider myself qualified to come up with my own: I'll cede to the real experts - the ones who wrote the report and the ones who decided to abbandon the firefighting efforts.

I am interested in hearing from people involved in the metal trade, particularly those involved in fatuige testing metal materials...if they come here.

I studied metal fatigue in materials engineering. I asked before: what does any of this have to do with fatigue? A building is a static structure.

In fact they can't explain it Russ. Thats the point. All your arguments are null and void as in the end the reports DO NOT claim to know the cause.

"They" cannot help. Can anyone else here?

That's a distortion. They cannot be 100% certain of the cause, but they can be pretty sure - perhaps 90% certain on most issues. When you say "do not claim to know the cause" that implies that they have no idea. That isn't the case at all.

 

[russ_watters]

You claim fire fighters in Building 7 reported that the fires were such that the building was in danger of collapsing.

Fine.

You seem to trust the opinion of firefighters.

In that case we seem to have a problem of sorts with your logic.

It is WELL reported and ON THE RECORD that firefighters in the towers reported small fires that would be easily contained and extinguished. It is also ON THE RECORD that not ONE firefighter believed there was ANY chance of those buildings collapsing. Minutes later the first of the Towers suffered a catastrophic collapse.

Which will it be?

Or will you simply be picking and choosing your line of thought to suit yourself?

AFAIK, no firefighers were able to get to the floors with fires on them, so its pretty obvious that they wouldn't have had any fires to report. So there isn't any contradiction there.

 

[russ_watters]

Regarding my tone, the only thing I posted with any tone to it was this:

If you really posted this thread out of concern over the possibility of other buildings collapsing on your friends...

That is intended to imply that your concern, would be a very unique one. I've never seen it before. Yes, it also implies that I question whether the concern is real, but given its unusual nature, that's a fair question.

You threw a comment about being called a "whacky conspiracy theorist" at me, but I never used the term. Fred made some offhand remarks about it, perhaps your replies were meant for him - since you didn't quote anyone or respond directly to any specific arguments made, its impossible to tell.

Regarding Fred's tone, there are, almost exclusively, two types of people who bring up the mode of collapse of the buildings on 9/11: Those who just don't know and are asking how it happened (those types are rare and they've never even heard of WTC7). And those who are pushing conspiracy theories. The tone of your first post looks like the typical 'I'm-really-only-looking-for-answers' first post bait of a conspiracy theorist looking for a fight. The fact that you so quickly jumped to over-the-top hostility,that you are utterly dismissive of the official reports (without citing specific parts), that you "demand answers" but refuse to accept the ones given, and that you didn't respond to specific arguments of others also fits that mold.

So here's the deal: either change your tone and the approach to your arguments or this thread won't be allowed to continue.

 

[brewnog]

I think that it's fair to say, from Noddy's mention of "fatigue", that he doesn't really know what he's talking about.

Noddy, if I've got this wrong, and you are in fact a chartered structural engineer who disagrees with the reports (both official and anecdotal) of every structural engineer I've spoken to regarding the matter, then please forgive me.

 

[Fran Lepton]

Interesting discussion. I was able to find some of the videos on the web (filmed from CBS, PBS and others) and I noticed an interesting element of the collapse. Upon close inspection it seems that the "penthouse" at the top of the building seems to collapse at almost the exact same time as the building starts to collapse downward at the base. This seems to imply that either there were two virtually simultaneous failures or that a very rapid internal failure caused this. As my engineering background did not specialize in building design I'm at a loss as to the most likely reason for this. Any thoughts on this aspect?

 

[Noddy]

I do not know how to operate the functions here...quotes etc...so i am at a disadvantage. Also...i must earn a living.

Forgive my tone as I am sick and tired of being labelled a "Conspiracy Theorist" because "experts" were quite specific in that they COULD NOT explain the collapse.

As for my use of "fatigue"...excuse me...but does not a metal structure, exposed to RAGING inferno's "fatigue"...

Where do you get the %90 sure from? From your head? Your OWN intuition?

You are a scientist when it suits and a "intuitive" when it suits, while you accuse me of attachment to the latter.

You know DAMN well "experts" were rubbing their heads with DISBELIEF when the Towers came down and ESPECIALLY when 7 came down.

Did the premiere fire fighting magazine label the investigation into the Towers and 7 collapses a "FARCE" or not? Actually, it was ..."a half baked farce". So sure of the data Russ? Coz that is what you're going on with such pious surety. Are you a man of science or just using the second hand "half baked farce" data and adding in your OWN intuition?

The constant mantra is that this event was "unique". What claptrap! You do not need an EXACT previous event to enable you to come to some viable conclusions! Is science forever reinventing the wheel from scratch? How much data is available from 100's of years of building structures? How much data is available from the study of metals under stress? How much data is available from the military on the penetrative qualities of various moving objects? The data available which could be put to use is endless. The practical knowledge of the many disciplines is endless.

Of course, if you are conducting a "half baked farce" your ability to combine data and come to conclusions is SEVERELY hampered.

The fire fighters never got to the fires? Well, well Russ. Go to a google search and find the transcripts and MP3 files where you will hear with your own ears firefighters stating CLEARLY that the fires were small and easily containable. The fire fighters are also clearly heard stating what "they" beleived to be explosions going off in the Towers.

You will find COUNTLESS, on the record comments by fire fighters and engineers (including the builder of the Towers) that they never thought for a second those towers would come down. And then their is the "free fall", CATASTROPHIC collapse.

The Towers were hit by a "hollow" aluminium tube designed to fly through the air...not a oversized DU penetrator rod from a Abrams main battle tank. They carried EXTREMELY low volatility jet fuel of which the majority burned outside the building. People are CLEARLY seen at the impact point of the aircraft indicating NO inferno "weakening" HUGE central and outer columns.

As for the 22,000 gallons of deisel in building 7...is it not reasonable to expect if this "container" was "feeding" the fires that we would have seen a massive fireball well BEFORE the 7 hours had passed? Would not the fires have made their way, as they do, to the source, and over a period of time heated the 22,000 gallon container to the point of a massive explosion? Whether low volatility deisel or not. After all, these fires weakened MASSIVE steel beams to the point of failure and did so, so the building collapsed in a PERFECTLY symmetrical pattern (of course someone stated there was in fact a kink, woopdy). I see what i can see.

I know many EXPERTS...

When in doubt..."FUDGE THE NUMBERS".

"Hey Bob! These results ar'nt very statistically significant, pass me the other software package...we'll keep that funding yet."

I take it you are familiar with the Oklahoma city bombing? Where a low velocity Ammonium Nitrate Fuel Oil truck bomb is supposed to have demolished the reinforced concrete columns of a large building from up to 100ft away? The just retired head of Airforce Weapons Testing considered the "official" report a "joke". Explosive charges were CLEARLY placed directly on the columns and it was reported far and wide that several more "unexploded" devices had been removed by authorities. This "official" report, another "fully baked farce" stands in open contrast to the OBVIOUS facts known by ANYONE who works with explosives. The official report is TOTAL hogwash...like so many...

They spent a HUGE amount more on why the shuttle disintergrated (dragged kicking and screaming mind you) but "starved" the investigators of the collapse of the WTC buildings of funds to the point where MANY quit in disgust. Again...do a internet search. ALL mainstream articles.

The key to your OWN hubris and OWN downfall is the fact that you rely on a report, described by MANY "EXPERTS" as a "half baked farce". You rely on data that is described as a "half baked farce". Your data is therefore a "farce" and your conclusions OBVIOUSLY so.

Your conclusion is cast in stone based on the fact that you cannot see what is before your eyes because you cannot make the next leap. It is simply out of your narrow paradigm and would involve a "reasonably" broad knowledge of geo-politics, economics and history plus a good dose in the psychology of tyrants and their tactics. My house wife Mother possesses this.

Again is there ANY "specialists" out their familiar with the qualities of metals under stress who can cast some light on the "symetrical free fall" of Building 7 which was hit with debris causing MINOR damage at best, alight on several floors burning carpet, wood, fittings etc...alledgedly/maybe being fed by a 22,000 gallon store of deisel which remained UNAFFECTED by said RAGING INFERNO's progress.

A steel structure has collapsed under dubious circumstances. Funding for an investigation was with held. Experts in the field consider the OFFICIAL REPORT a "half baked farce". Perhaps some simple testing of identical structures on a small scale can shed some light on the mystery.

 

[Astronuc]

Interesting discussion. I was able to find some of the videos on the web (filmed from CBS, PBS and others) and I noticed an interesting element of the collapse. Upon close inspection it seems that the "penthouse" at the top of the building seems to collapse at almost the exact same time as the building starts to collapse downward at the base. This seems to imply that either there were two virtually simultaneous failures or that a very rapid internal failure caused this. As my engineering background did not specialize in building design I'm at a loss as to the most likely reason for this. Any thoughts on this aspect?

All that would mean is that that core (center of the building) was collapsing first. The core, near the elevator shafts, may have been affected by the fires.

When buildings are demolished, the explosives are located and timed, so that the building falls in on itself. Note - I am not saying that someone deliberately demolished WTC 7. All I am saying is that if the core was undermined, the penthouse would fall in, and the building would collapse around the core, hence the 'apparent' symmetry - so there are no surprises.

When one part a building fails, loads are shifted and may exceed the design load eslewhere, then the failure propagates.

The kink in the structure happened where one would expect it to happen, given the situation.

 

[Pengwuino]

haha adn you guys thought he was asking legitimate questions. Obviously only metallurgists can be experts on how a structure collapses.

 

[Noddy]

Core Collapse

Thanx for your input Astronuc.

With respect, there is a BIG difference between carefully placed and timed explosive charges which "cut" like a knife through large metal beams instantly and a "fire", weakening metal support structures at VARIOUS points in the building at VARYING rates.

The beautiful take downs of large buildings is an EXACT science reproducing those beautiful SYMMETRICAL collapse patterns.

I see what i can see. Instant, catastrophic collapse in a symmetrical pattern. Unattainable by random fires.

A VERY simple scale model of 7 could be constructed and a REASONABLE reproduction of events made.

This would cost government agencies VERY little.

I would like to see some private citizens take on this task.

The former head of Airforce Weapons Testing did this in light of the ridiculous conclusions of the Olklahoma city bombings. The results were predictable. IMPOSSIBLE.

 

[Noddy]

To Pengwino

The key lies in the the fact that you and others state that a RAGING INFERNO of wood, carpet etc fed by a 22,000 gallon deisel fuel container, which failed to explode when surrounded by SAID "raging inferno" caused HUGE, LOAD BEARING, CENTRAL SUPPORT COLUMNS to collapse in a symmetrical, instant and catastrophic fashion.

The question is clear.

Your response to my post says more about you then it does about me.

Being a smart arse does not help solve the puzzle. But again, says much about your character.

 

[russ_watters]

As for my use of "fatigue"...excuse me...but does not a metal structure, exposed to RAGING inferno's "fatigue"...

No, it doesn't. Apparently, you are using the term as a layman's term to describe how metal weakens when heated (and it does weaken when heated). But that's not what the word means in an engineering sense: fatigue is the weakening caused by repetititve stress. When the wings of an airliner flap due to aerodynamic stresses, they can fatigue. That's why airplanes have a maximum lifespan. When you repetitively bend a paperclip and it eventually breaks, that's fatigue.

Buildings undergo constant/static stresses - they do not fatigue (if they did, they'd collapse on their own after a certain amount of time).

You know DAMN well "experts" were rubbing their heads with DISBELIEF when the Towers came down and ESPECIALLY when 7 came down.

No, actually, they weren't. Anyone watching TV or reading a newspaper in the days after 9/11 heard/read the opinions of countless engineers hired by independent news organizations to give analysis of the collapse of the towers. The conclusions were specific and uniform and agreed with the government report, which they preceded by many months. While there were some interesting and unique aspects to it, there was nothing particularly surprising about the collapse of the towers themselves.

 

[Pengwuino]

The key lies in the the fact that you and others state that a RAGING INFERNO of wood, carpet etc fed by a 22,000 gallon deisel fuel container, which failed to explode when surrounded by SAID "raging inferno" caused HUGE, LOAD BEARING, CENTRAL SUPPORT COLUMNS to collapse in a symmetrical, instant and catastrophic fashion.

The question is clear.

Yes, good thing i never said anything

Your response to my post says more about you then it does about me.

Being a smart arse does not help solve the puzzle. But again, says much about your character.

It shows that this is about the 300,000,000th thread saying the structural collapses on 9/11 were fake and me, like many others, are sick of wasting our time on people like you who think there has to be some sort of conspiracy going on.

 

[Noddy]

Pengwino You Have Answered Your Own Questio...

You are not interested.

You may leave.

Bye, bye...

Anyone else out there?

 

[russ_watters]

With respect, there is a BIG difference between carefully placed and timed explosive charges which "cut" like a knife through large metal beams instantly and a "fire", weakening metal support structures at VARIOUS points in the building at VARYING rates.

The beautiful take downs of large buildings is an EXACT science reproducing those beautiful SYMMETRICAL collapse patterns.

I see what i can see. Instant, catastrophic collapse in a symmetrical pattern. Unattainable by random fires.

Since you have now confirmed our suspicions that you believe that WTC7 (and, you implied, WTC1 & 2) were felled in a controlled demolition, the term "conspiracy theory" does apply and this thread is not one about engineering. Moving to skepticism and debunking.

 

[Noddy]

Ah Russ...Thankyou...

When in doubt, Da Nile becomes more than a river in Egypt.

You are obviously not "qualified" to answer my question Russ so you are free to move on to somewhere else.

Again, anyone with a background in the properties of metals under heat stress out their.

I have a very SPECIFIC question. Not %90 of a question.

 

[Pengwuino]

Noddy, your exhibiting another trademark quality of conspiracy theory nuts. "Only people who agree with me are experts"

 

[russ_watters]

You've heard the opinion of a number of engineers here, Noddy, you've read the opinions of countless others, but you dismiss all of them in search for one who can support the conclusion you have already reached on your own - even while demonstrating a basic lack of understanding of the engineering involved. That isn't a scientific way of thinking. You'll find little sympathy for that attitude here. You'll only find real scientists and real engineers expressing real engineering opinions.

 

[Noddy]

Just WHICH experts are you referring to?

It took months for the "experts" to come up with the ...quote..."truss theory".

The look on the building designers face says it all in the interview conducted after the collapse.

Answer my questions Russ...Super Mentor.

You cannot.

You and the rest of your ilk are the "specialized" idiot class who would believe Noddy and Big Ears flew into those towers because a government "expert" told you so.

I've finished playing with you.

Twas fun.

 

[russ_watters]

You and the rest of your ilk are the "specialized" idiot class who would believe Noddy and Big Ears flew into those towers because a government "expert" told you so.

I've finished playing with you.

Twas fun.

Fair 'nuff... good riddence.