An Analysis of the WTC on 9/11 . . .

reply to post by FDNY343


After your claim that you're smarter than Newton, why would I answer any of your questions? Why do so many OSers feel they are entitled to ask all the the questions? Once you demonstrate how your silly wing can cut my wood stove in half, we can talk.

reply to post by FDNY343


Did you escalate this issue? I think I may have met your supervisor.

Originally posted by pteridine
reply to post by Yankee451

 

Here is the MIT paper. It is a far more complex calculation than some would have you believe.

web.mit.edu...

www.abovetopsecret.com...

Check out the MITs take on the wing cutting steel question.

Originally posted by bsbray11

Learn to read:

Thus, the floors did not fail progressively to cause a pancaking phenomenon.

wtc.nist.gov...


It doesn't say "during initial only." If floors were pancaking then that would automatically mean you were already past initiation.

Need more hints?

Not from you. You still do not understand that this is talking about collapse initiation.

Originally posted by bsbray11
And that's the term NIST used, but saying it was therefore a pancake collapse is saying a fruit is an apple. An apple is a fruit but not always the other way around. NIST has explicitly contradicted pancake theory in particular in itself mechanisms and that's why you're wrong for posting like pancake theory is still legitimate.

Again, the pancake theory was dismissed as the collapse INITIATION!

Originally posted by bsbray11
And before you ask, what theory did NIST offer instead of pancake theory? None, because they didn't analyze the global collapse. There's what your tax money got you. But you didn't read the report apparently so what difference does it make to you anyway.

I haven't read the report?!?! Laughable! Took me about 4 weeks to read the entire thing.

And again, NIST was not tasked to explain the ENTIRE collapse, as that would have been nearly impossible, and the accuracy would have been questionable. But hey, why don't you get Gage et al. that have this knowledge to do it?

Oh, that's right, they won't.

Originally posted by bsbray11
More educated people than myself already have, so what's the point in beating a dead horse? Bazant assumes 50-95% of the total mass of either tower remains in the footprint the whole time, and his model is dependent upon that. That and a photo of Ground Zero is all you need to know his model is crap.

Two things.

1-Please cite this paper that is submitted as a discussion to Bazant's paper. Heiwa (Anders Bjorkman [SP?] tried, and Bazant responded and explained where he went wrong.) Maybe a "Truther" from the 9/11 T.M. could publish a paper showing Bazant wrong in any of the dozens of respectable journals? When will this be published? I mean, if Bazant's conclusions are so incorrect, it should be easy, right?

Right?


Oh, that's right. It hasn't happened, and most likely never will.

2- Bazant's assumtions are correct, as far as I can see. The 50-95% would seem accurate, since alot of the debris that ended up in the basement was from the floors above. Imagine that.....

Originally posted by Yankee451
After your claim that you're smarter than Newton, why would I answer any of your questions?

I never claimed that at all. Don't put words into my mouth.

Originally posted by Yankee451

Why do so many OSers feel they are entitled to ask all the the questions? Once you demonstrate how your silly wing can cut my wood stove in half, we can talk.

Why do CTs feel that they are entitled to ask all the questions, but never answer any?

Originally posted by bsbray11
Hardly any debris at all was left in the footprints.

Originally posted by bsbray11

The debris pile didn't extent beyond where the lobbies used to be, and that's including still-intact core and perimeter structure at the lobby level.

You DO realize that these two statements are mutually exclusive, right?

You also realize they they are both incorrect, right?

Originally posted by Yankee451
reply to post by FDNY343

 

Did you escalate this issue? I think I may have met your supervisor.

Wonderful guy he is eh? Tell him I need another raise!!

Originally posted by Yankee451

www.abovetopsecret.com...

Check out the MITs take on the wing cutting steel question.

Yep, what do you think the conclusion is?

Hint-Only about 3-4% of the total energy is lost to the exterior columns.

This paper doesn't say what you think it does.

reply to post by FDNY343


Read the report, you haven't read it or you're being disingenuous. Their modeling was heavily tilted to meet their desired results. You can read my response to your boss:

Originally posted by Yankee451
reply to post by pteridine

 

Taking the estimated airplane mass at the point of impact to be M = 127 tons and the impact velocity of 240m/s o V = , the energy of the striking aircraft was 3658MJ KE.

3.3 Engines and wing damage The engines are the only components of the aircraft that can be considered approximately as rigid bodies. Their devastating power is unmatched until they encounter an object of similar weight and strength.

In the experimental study in which an engine of a transport aircraft hit a thick concrete wall, the engine itself was crashed and fractured, so it was not rigid, [28]. However, in contact with less substantial members the engine could cut and plow through the various structural members of the WTC Towers until all their kinetic energy is absorbed.

I don't see them calculate the mass of the whole building anywhere, where is that figured? They calculate the mass of the 767, which like a building's mass, is just the sum of it's parts. Are they conducting an honest study? The part about the engine hitting a thick concrete wall will help over on the Pentagon thread though...thanks. Otherwise it looks like they're setting up a whitewash study, judging by the parameters they're limited to.

Wings of modern transport aircrafts are quite complicated structures consist of open section beams, ribs and a skin reinforced by stringers. Together they form a very stiff and strong box-type section. Determination of the strength of the wing relative to the strength of the floor structure will require a detailed finite element analysis, which we believe has not been performed to date. In order to retain the needed degree of simplicity, two models were developed.

In one model the wing material is lumped into single box-type beam. In the second model, the solidity ratio are determined for both the wing and the floor and then are compared. The main structural part of the wing is the spar – a continuous beam that extends from one tip of the wing to the other. For modeling purposes, we assumed that the mass of the wings (excluding engine) was approximately 21300kg wing M = . This mass does not include the mass of the fuel in the wing tanks.

Assuming that this mass is now uniformly distributed over the whole wing span

It isn't. Most of the mass is between the fuselage and the engine.

and the wing is modeled as a thin-walled square section crosssection (c ´4c ) with the thickness ( eqw t ), the equivalent thickness of the wing beam can be found from the equation (10 ) eqw w Al wing ct l r = M (8) Taking an average height of the spar to be c = 480mm and the span of the aircraft 47.57m w l = , the equivalent thickness becomes 34.5mm eqw t = . The wings are swept at approximately 35o so that upon impact, external columns are contacted sequentially, one by one. However, the problem of a hollow beam striking another hollow column at a right angle and a speed of 240 m/s has not been analyzed in the literature. Therefore it is not possible, at this point in time, to give any detailed account on this interaction, between the wings and outer column, with a higher degree of accuracy than our approximate engineering analysis.

What? Therefore it is not possible? Therefore it is not possible this report proves squat. Why would 35 degree swept wings strike the individual columns at right angles anyway? Wouldn't the swept wing strike the corner of the first column at 240 m/s, and slow down as it hit the next column, as the fuselage is slowing down against the lateral resistance of at least two floors? Their modeling appears to be done to explain how a plane could do it, not how it was done. Note their language throughout the report...the plane "could" have struck here...why are they guessing? Don't they have the Naudet footage? Aren't they the experts?

The equivalent thickness of the hollow wing beam is approximately four times larger than the
thickness of the exterior columns, 9.5mm ext t = . It is therefore reasonable to treat wings as
rigid bodies upon impact with exterior columns. By the same token, the equivalent thickness of
wings is smaller (about half) than the equivalent thickness of the floor structure (to be
calculated in the next section). Consequently it would appear that the floors will cut through
the wings without being severely damaged themselves. In actuality the wings are constructed
as a 3-dimensional lattice of open section beams, ribs and sheet metal skin that maybe of
comparable strength to the floor trusses. However, interaction between two 3-dimensional
space frames impacting each other is too difficult to carry out analytically at the present level
of approximation.

Can you explain this one to the class please? Do I see them rolling all the material that would comprise a wing into a big ball of aluminum play doh, and reforming it all in wing shape so that the wing is now equally massive from tip to root, and all the material is equally distributed to a thickness of 9.5 mm? Why is this model wing approximately four times the thickness of the model column? On the next page they're saying they really don't know that either but they're guessing it's about 9.5 mm, so that one threw me for a loop, but I'm no expert so can you help me out? Isn't a real wing's skin thickness about 2 or 3 mm at most?

So now the wing has half the mass at the tip, and is 9.5 m thick, what do they do to the building? Do they include the mass, or make a big ball of steel play doh and reconstruct it so it will be easier to model? From what I see they take out the core and treat the model to only 40% of the building. When they're done tweaking these things, then they start the test using a flurry of hieroglyphic gibberish sure to dissuade curious eyes.

They even try to convince their readers the wings were comparable in strength to the WTC tower floors, but my eyes glazed over at that point.

Is there any need to continue with this vaunted study from MIT?

Originally posted by psikeyhackr
An implosion is the result of pressure from all around an object resulting in it being crushed inward.

An implosion is what happened to the plutonium in the Fat Man bomb that was dropped on Nagasaki. An implosion is what happens to a submarine that goes to deep. I doubt that any building has ever actually been imploded on the Earths surface.

What are you waffling on about.

Why do you keep proving how clueless you are.

NOVA: A common misconception is that you blow buildings up. That's not really the case, is it?

Stacy Loizeaux: No. The term "implosion" was coined by my grandmother back in, I guess, the '60s. It's a more descriptive way to explain what we do than "explosion."

www.pbs.org...

Originally posted by wmd_2008
BINGO YOUR A***

They were 1450 ft tall because of this and the FLOOR CONSTRUCTION thats why the debris looked like it did, CONTROLLED DEMOLITIONS ARE CONFINED TO A SMALL AREA DOH!!! Thats the point of a controlled demolition!!!!

Also you do remember how the South Tower collapse started DONT YOU!

No a controlled demolition does not mean its confined to small space, yelling it doesn't change that fact mate.

A controlled demotion that is designed to bring the building down into its footprint is known as an 'implosion demolition'.

How did the south tower collapse start, by it tilting 15d? What has that to do with implosion demolition?

Originally posted by Varemia
reply to post by ANOK

 

I don't think I've ever seen anyone besides Truthers saying that it fell inside its footprint. Now it feels like you are creating an opposition just to say that you are right.

Well the problem is for the OS to be correct there would HAVE to be floors still in the footprint. There is no way floors can all destroy each other completely with nothing left.

With everything outside the footprint contradicts the OS claim.

Don't get confused with WTC 7 which WAS an implosion demolition, it landed mostly in its footprint.

In the collapse, doesn't it make sense that it is uncontrolled?

Controlled in this context means it was not natural, someone had to have set it up to collapse that way. If the debris lands outside the footprint then that is the way whoever controlled it wanted it.

In fact, the widespread damage contradicts a controlled demolition. Sure, you could argue that it was a controlled initiation, but there was nothing controlled about the collapse, and since we have an alternative initiation that requires no imagination to find (the plane, damage, and fire), this controlled demo stuff seems more and more like fantasy.

Again you keep thinking controlled means the buildings collapse would be 100% perfect, no it is still a controlled demolition if someone initiated the collapse no matter what happened afterwords. Again if the plan was for the building to eject all its debris outwards, and that's what they caused to happen, then it was controlled.

The towers were too tall for implosion demolition, there is no way you can get 110 floors in that small of a footprint. This is why no building that tall have ever been imploded. WTC 7 would be the tallest if it was official excepted, 47 floors. No other building that tall has been attempted.

Originally posted by ANOK

Originally posted by wmd_2008
BINGO YOUR A***

They were 1450 ft tall because of this and the FLOOR CONSTRUCTION thats why the debris looked like it did, CONTROLLED DEMOLITIONS ARE CONFINED TO A SMALL AREA DOH!!! Thats the point of a controlled demolition!!!!

Also you do remember how the South Tower collapse started DONT YOU!

No a controlled demotion does not mean its confined to small space, yelling it doesn't change that fact mate.

A controlled demotion that is designed to bring the building down into its footprint is known as an 'implosion demolition'.

How did the south tower collapse start, by it tilting 15d? What has that to do with implosion demolition?

They use the term "imlposion" so that the neighbors don't go screaming that so and so wants to blow up the building down the street. Its still an explosion. They try to minimize the amount the material travels for economic purposes and for safety. This "fall in own foot print" is utter and complete nonsense. Just as many demolitions are designed to drop the building outside of its foot print. Its safety and money that drives the demolition design, there's no standard method - each project is approached as an individual event.

Originally posted by hooper

Originally posted by ANOK

Originally posted by wmd_2008
BINGO YOUR A***

They were 1450 ft tall because of this and the FLOOR CONSTRUCTION thats why the debris looked like it did, CONTROLLED DEMOLITIONS ARE CONFINED TO A SMALL AREA DOH!!! Thats the point of a controlled demolition!!!!

Also you do remember how the South Tower collapse started DONT YOU!

No a controlled demotion does not mean its confined to small space, yelling it doesn't change that fact mate.

A controlled demotion that is designed to bring the building down into its footprint is known as an 'implosion demolition'.

How did the south tower collapse start, by it tilting 15d? What has that to do with implosion demolition?

They use the term "imlposion" so that the neighbors don't go screaming that so and so wants to blow up the building down the street. Its still an explosion. They try to minimize the amount the material travels for economic purposes and for safety. This "fall in own foot print" is utter and complete nonsense. Just as many demolitions are designed to drop the building outside of its foot print. Its safety and money that drives the demolition design, there's no standard method - each project is approached as an individual event.

Yep, "CONTROLLED" means it does what the designers want it to. If they get it right of course.

None of them are actual implosions.

psik

reply to post by FDNY343


Bazant has a lot of reports out there...he's an expert's expert it seems.

What Did...

What Did and Did not Cause Collapse of WTC Twin Towers in New York

Although NIST did not analyze the overall process of dynamic progressive collapse below the fire zone, it verified a sequence of effects that triggered the collapse:

(1) scraping of much of steel insulation by flying objects during aircraft impact (without which the towers would not have collapsed, as concluded by NIST);

They analyzed 1% of the steel. Where do they get the information to make such a claim? Were they inside the building? The photographic evidence of the North Tower shows no fire in the gash, and people visibly waving for help for some time. Where do they source this claim?

(2) cutting of many columns, and damage with large deflections of others during aircraft impact;

Cut by what? The aluminum knife wings from the MIT report? Notice the direction of the damage of the columns in the image below and also notice that even with 35 degree swept-back knife-wings a 767 would slice from the inside out. Why are the dents in the columns going outside in? Why didn't Bazant notice that?

[atsimg]http://files.abovetopsecret.com/images/member/24e4da0adf94.jpg[/atsimg]

(3) subsequent load redistributions among columns;

They could tell by looking at them? If they can calculate their load redistribution, why can’t they accurately calculate the exact damage?

(4) sagging of heated floor trusses and their catenary action, evidenced by multistory inward bowing of perimeter columns; and

Heated by what? The kerosene burnt up on impact, igniting polyester rugs and office cubicles? There was no hot fire as evidenced by the people looking out the North Tower gash.

(5) viscoplastic buckling of heated, damaged and overloaded columns.

Overloaded by what, the load distribution they assumed in #3? Why are they making so many assumptions for a scientific paper?

Although a detailed computer analysis of columns stresses after aircraft impact is certainly possible, it would be quite tedious and demanding, and has not been carried out by NIST.

Undeclared wars are tedious and demanding too, why the hell hasn’t this detailed analysis been done?

Nevertheless, it can easily be explained that the stress in some surviving columns most likely exceeded 88% of their cold strength _0.

If it can be easily explained, why don’t they do it? Notice their language, “most likely”…why do they say that? Is this report being built to reach a desired result, or are they simply trying to explain how it “could” have happened?

In that case, any steel temperature _ 150_C sufficed to trigger the viscoplastic buckling of columns (Baˇzant and Le 2008). This conclusion is further supported by simple calculations showing that if, for instance, the column load is raised at temperature 250_C from 0.3Pt to 0.9Pt (where Pt = failure load = tangent modulus load), the critical time of creep buckling (Baˇzant and Cedolin 2003, chapters 8 and 9)

Can I start using myself as a reference for my arguments?

Creep usually accurs over time, from what Frost and Ashby say. Why do they make so many assumptions, why don’t they try to investigate how much heat was absorbed by the steel in thermal transfer? They say the heat isn’t needed to prove collapse, meaning that the collapse would have happened even without the fires? So they're changing his tune from 2001 now, that’s cool, but why don’t they consider the photographic evidence and eye witness accounts which lean towards something other than either fire or collapse? Something was melting steel; why don’t they address that? Why do they refer to heat so often in their initial five points if heat wasn’t a factor? Is this report meant to explain the OS of collapse based on a blizzard of formulas, or show what really happened?

Because the energy dissipation by buckling of the hot columns must have been negligible by comparison, most of this energy must have been converted into kinetic energy

Notice their language. Are they guessing? “Must have been”…why must it have been? Are they searching for a way to fit that into their model?

This is the basic characteristic of progressive collapse, well known from many previous disasters with causes other than fire (internal or external explosions, earthquake, lapses in quality control; see, e.g., Levy and Salvadori 1992; Baˇzant and Verdure 2007

The author uses examples of bridge and stadium collapses to make his case, and then back to himself as another reference. Are spanning structures like bridges and stadiums fair comparisons for the twin towers, and the rest of the WTC complex? Is it fair to reference one’s own work here?

Just a few thoughts about their methods...

Originally posted by hooper

They use the term "imlposion" so that the neighbors don't go screaming that so and so wants to blow up the building down the street. Its still an explosion.

LOL

No they use the term implosion because it explains better what the building does. It falls inwards towards itself, rather than outwards as an 'explosion' would. The building is not exploded in an implosion demolition, part of the building are weakened with explosives in sequence allowing the building to fall in on itself, like WTC 7 did.

They try to minimize the amount the material travels for economic purposes and for safety. This "fall in own foot print" is utter and complete nonsense.

What?

Sometimes, though, a building is surrounded by structures that must be preserved. In this case, the blasters proceed with a true implosion, demolishing the building so that it collapses straight down into its own footprint (the total area at the base of the building). This feat requires such skill that only a handful of demolition companies in the world will attempt it.

science.howstuffworks.com...

Just as many demolitions are designed to drop the building outside of its foot print. Its safety and money that drives the demolition design, there's no standard method - each project is approached as an individual event.

Each project is approached differently because buildings are not all the same. There are standard methods, it's just the placement and timing of the explosives that change depending on how they want the building to fall.

Explosive demolition is the preferred method for safely and efficiently demolishing larger structures. When a building is surrounded by other buildings, it may be necessary to "implode" the building, that is, make it collapse down into its footprint.

science.howstuffworks.com...

Please stop with this silly argument you are just distracting from the point of the thread.

For an antidote to some of the nonsense from FDNY343 above, here is a recommended article by Kevin Ryan, www.911review.com... A couple of key paragraphs make these observations:

The Twin Towers and Why They Fell

It would help to begin with an accurate description of the WTC towers in terms of quality of design and construction. In July of 1971, the American Society of Civil Engineers (ASCE) presented a national award judging the buildings to be "the engineering project that demonstrates the greatest engineering skills and represents the greatest contribution to engineering progress and mankind."3 Others noted that "the World Trade Center towers would have an inherent capacity to resist unforeseen calamities." This capacity stemmed from the use of special high-strength steels. In particular, the perimeter columns were designed with tremendous reserve strength whereby "live loads on these columns can be increased more than 2,000% before failure occurs."4

and

NIST and Underwriters Laboratories

In August 2004, Underwriters Laboratories evaluated the Pancake Theory by testing models of the floor assemblies used in the WTC buildings. Despite all the previous expert testimony, the floor models did not collapse. NIST reported this in its October 2004 update, in a table of results that clearly showed that the floors did not fail and that, therefore, pancaking was not possible.14 NIST more succinctly stated this again in its June 2005 draft report, saying: "The results established that this type of assembly was capable of sustaining a large gravity load, without collapsing, for a substantial period of time relative to the duration of the fires in any given location on September 11th."15

The remainder of the article has much of value in rebutting false information on this thread and elsewhere.

reply to post by JimFetzer


Hi Jim...

I'm an ex S911T member...I pretty much just swept the parking lot for you guys. (I'm in disguise now).

Anyway, I believe the evidence is pretty clear that conventional methods were used to bring down the towers.

I'm interested to know what you think the motivations were for 911. I've read that there was much more at stake than just starting wars, so in light of Operation Brownstone and Operation Code Angel, can you comment on why tried and true conventional means wouldn't be used when so much was at stake?

Originally posted by JimFetzer
For an antidote to some of the nonsense from FDNY343 above, here is a recommended article by Kevin Ryan, www.911review.com... A couple of key paragraphs make these observations:

The Twin Towers and Why They Fell

It would help to begin with an accurate description of the WTC towers in terms of quality of design and construction. In July of 1971, the American Society of Civil Engineers (ASCE) presented a national award judging the buildings to be "the engineering project that demonstrates the greatest engineering skills and represents the greatest contribution to engineering progress and mankind."3 Others noted that "the World Trade Center towers would have an inherent capacity to resist unforeseen calamities." This capacity stemmed from the use of special high-strength steels. In particular, the perimeter columns were designed with tremendous reserve strength whereby "live loads on these columns can be increased more than 2,000% before failure occurs."4

and

NIST and Underwriters Laboratories

In August 2004, Underwriters Laboratories evaluated the Pancake Theory by testing models of the floor assemblies used in the WTC buildings. Despite all the previous expert testimony, the floor models did not collapse. NIST reported this in its October 2004 update, in a table of results that clearly showed that the floors did not fail and that, therefore, pancaking was not possible.14 NIST more succinctly stated this again in its June 2005 draft report, saying: "The results established that this type of assembly was capable of sustaining a large gravity load, without collapsing, for a substantial period of time relative to the duration of the fires in any given location on September 11th."15

The remainder of the article has much of value in rebutting false information on this thread and elsewhere.

edit on 21-3-2011 by JimFetzer because: (no reason given)

1) Suggest you find out what is ment by a live load!!!!!!

2) Did they test the floors with damaged connections or other floors falling on top !!!!!

Oh and congratulation on your other thread being closed no planes

reply to post by wmd_2008


The no planes threads are relegated to the HOAX section by policy of ATS.

Even clear evidence of no planes, like the directional damage images I've provided, will be considered a hoax by this site. No evidence will be considered if it contradicts the OS. Period.

Why would anyone try to limit the areas of investigation regarding the crime of the century? Why do people like you resort to barrages of ridicule instead of rational discussion about all possibilities?

"The smart way to keep people passive and obedient is to strictly limit the spectrum of acceptable opinion, but allow very lively debate within that spectrum." — Noam Chomsky

www.goodreads.com...

reply to post by ANOK

No they use the term implosion because it explains better what the building does. It falls inwards towards itself, rather than outwards as an 'explosion' would. The building is not exploded in an implosion demolition, part of the building are weakened with explosives in sequence allowing the building to fall in on itself, like WTC 7 did.

Sorry, but of course your experience with construction and demolition is obviously limited to what you can Google and what you see on Youtube. In the real world all explosives explode outward, they are contained by mats and other containment materials. Not all demo's are designed to fall in on themselves.

Sometimes, though, a building is surrounded by structures that must be preserved. In this case, the blasters proceed with a true implosion, demolishing the building so that it collapses straight down into its own footprint (the total area at the base of the building). This feat requires such skill that only a handful of demolition companies in the world will attempt it.

You do realize what the word "sometimes" means, right? Sometimes means not all the time. Wow.

Explosive demolition is the preferred method for safely and efficiently demolishing larger structures. When a building is surrounded by other buildings, it may be necessary to "implode" the building, that is, make it collapse down into its footprint.

No, its not. Its a risky, dangerous and expensive proposition. Its the choice of last resort.

Please stop with this silly argument.....

Agree with you there. Get out in the world and get a clue.

Originally posted by ANOK

Originally posted by psikeyhackr
An implosion is the result of pressure from all around an object resulting in it being crushed inward.

An implosion is what happened to the plutonium in the Fat Man bomb that was dropped on Nagasaki. An implosion is what happens to a submarine that goes to deep. I doubt that any building has ever actually been imploded on the Earths surface.

What are you waffling on about.

Why do you keep proving how clueless you are.

NOVA: A common misconception is that you blow buildings up. That's not really the case, is it?

Stacy Loizeaux: No. The term "implosion" was coined by my grandmother back in, I guess, the '60s. It's a more descriptive way to explain what we do than "explosion."

www.pbs.org...

My point is that the "implosion" term as applied in destroying buildings is not accurate in terms of what implosion means in physics. So if we are trying to get people to understand why it is PHYSICALLY IMPOSSIBLE for airliners to destroy the towers then it is contradictory to not get the physics terminology correct.

What happened to WTC 1 and 2 were not "implosions" even by the word's inaccurate usage by the demolition industry.

It's like people talking about "FREE FALL SPEED" all of the damn time when there is no such thing.

It is FREE FALL ACCELERATION.

psik