Keith Seffen WTC Paper Out

[JamesB]

For all of you who do math better than I. It is via a troofer site, but I have no reason to doubt it is not valid.

http://winterpatriot.pbwiki.com/f/seffen_simple_analysis.pdf

[Gravy]

Thanks, James!

[JamesB]

I tried to read it, but except for part of the intro and conclusion it was way over my head. At least I was able to get through all of the Poteshman paper on the stock options. :D

Although I was disappointed to read the footnotes, and Judy Wood, David Ray Griffin and Jim Hoffman didn't get a single citation...

[Gravy]

Why, a child of four could understand Seffen's calculations! Unfortunately, it's too late here for me to corral such a child. I've verified as much as I can by counting on my fingers and by analyzing the patterns made by tossing cat whiskers onto beer coasters.

[Mangoose]

The paper is due to appear in the Journal of Engineering Mechanics, Vol. 134, No. 2, February 2008. The current issue out is Vol. 133, No. 11 (November 2007). This looks like a draft version.

[bofors]

For all of you who do math better than I. It is via a troofer site, but I have no reason to doubt it is not valid.

http://winterpatriot.pbwiki.com/f/seffen_simple_analysis.pdf

Thanks.

[bofors]

Those factors responsible for the onset of collapse are now well established. Despite
localised and substantial horizontal impacts by fuel-laden aircraft, both towers survived until the intense
fire compromised the ability of the remaining, in-tact columns close to the aircraft impact zones to
sustain the weight of the buildings above them. The subsequent near free-falling of these upper parts
over the height of just one storey resulted in dynamical “over-loading” of the relatively undamaged
lower columns by a factor of 30 compared to their static load capacity, according to Ba?zant and Zhou
(2002).

"Free-falling... over the height of just one storey..."

What a bunch of crap, that obviously did not happen and is not even possible with demolitions.

[JamesB]

Those factors responsible for the onset of collapse are now well established. Despite
localised and substantial horizontal impacts by fuel-laden aircraft, both towers survived until the intense
fire compromised the ability of the remaining, in-tact columns close to the aircraft impact zones to
sustain the weight of the buildings above them. The subsequent near free-falling of these upper parts
over the height of just one storey resulted in dynamical “over-loading” of the relatively undamaged
lower columns by a factor of 30 compared to their static load capacity, according to Ba?zant and Zhou
(2002).

"Free-falling... over the height of just one storey..."

What a bunch of crap, that obviously did not happen and is not even possible with demolitions.

Nice quote mining, he says near free-falling. It changes the meaning. For example, you nearly know what you are talking about.

[bofors]

Nice quote mining, he says near free-falling. It changes the meaning. For example, you nearly know what you are talking about.

Cute... but this guy does not appear examine how far away from the truth "near" is.

This paper largerly appears to take the junk science served up by Bazant & Zhou, with their ludicrous multi-story "free fall" nonsense, and applies concepts associated with propagating instability phenomena to it.

While it may be interesting to probe equation (21) for condition of "collapse" stop, the only other thing this paper may good for is to see if it predicts asymmetric "collapse" propagation.

[Arus808]

Cute... but this guy does not appear examine how far away from the truth "near" is.

its a rough draft of a paper that is to be published in februrary.

NIST used NEAR free fall as well, care to actually read that report?

This paper larger appears to take the junk science served up by Bazant & Zhou, with their ludicrous multi-story "free fall" nonsense, and applies concepts associated with propagating instability phenomena to it.


coming from someone who has demonstrated time after time that doesn't understand basic high school physics.

[SDC]

Cute... but this guy does not appear examine how far away from the truth "near" is.

This paper largerly appears to take the junk science served up by Bazant & Zhou, with their ludicrous multi-story "free fall" nonsense, and applies concepts associated with propagating instability phenomena to it.

While it may be interesting to probe equation (21) for condition of "collapse" stop, the only other thing this paper may good for is to see if it predicts asymmetric "collapse" propagation.

Well, for heaven's sake, it is your responsibility to send a detailed criticism to the journal in which the article appears. Please get on it!

Seriously.

[DGM]

Well, for heaven's sake, it is your responsibility to send a detailed criticism to the journal in which the article appears. Please get on it!

Seriously.
We should try to help him out. What's a "sciencey" word for "gut feeling"?

[peteweaver]

Cute... but this guy does not appear examine how far away from the truth "near" is.

This paper largerly appears to take the junk science served up by Bazant & Zhou, with their ludicrous multi-story "free fall" nonsense, and applies concepts associated with propagating instability phenomena to it.

While it may be interesting to probe equation (21) for condition of "collapse" stop, the only other thing this paper may good for is to see if it predicts asymmetric "collapse" propagation.

Bofor's what don't you understand about Youngs Modulus that makes you think its "Junk Science" ?

IF you think its nonsense, the onus of proof is upon you to back your claim up with more than empty words.

Instead of providing any scientific facts, your post just seems to be an attack Doctor Seffen for saying something that you do not like.

Can you not understand that there are thousands of Keith Seffens out there, who though not having written a paper on the collapse, understand all too well the fatal effect fire had on the already damaged structure, and these guy's would be up in arms, had a demolition by explosive charges taken place. Instead they just get on with their lives with the knowledge that its blimmin obvious what occured.

[Alferd_Packer]

We should try to help him out. What's a "sciencey" word for "gut feeling"?

“woman’s intuition?”

[slyjoe]

From Wiki:

Gut feelings are generally regarded as unmodulated by conscious thought.

Pretty applicable.

From the paper, it appears "near" is approximately 0.5. Am I reading this correctly?

[T.A.M.]

So how long before we see a "Critical Analysis" of the paper by a Theologian or Song Writer at Scholars?

TAM;)

[TShaitanaku]

We should try to help him out. What's a "sciencey" word for "gut feeling"?

Generally unqualified specious speculation?

[R.Mackey]

My compliments to Dr. Seffen, for a straightforward paper and a closed-form solution. The guy even gives us a Lagrangian.

That's one more peer-reviewed paper for the good guys. The opposition still stands at, let's see... carry the two... zero.

Is there anyone out there who still thinks the Truth Movement hasn't forfeit the contest?

[e^n]

Is there anyone out there who still thinks the Truth Movement hasn't forfeit the contest?

The Truth Movement.

[T.A.M.]

Maybe NWO Kitty could put them in touch with some "Purr" Reviewed Journals.

Thanks, I'll be here all week.

TAM;)

[16.5]

"Free-falling... over the height of just one storey..."

What a bunch of crap, that obviously did not happen and is not even possible with demolitions."

Typical analysis by bofors, misreads the sentence, misquotes it, and argues from disbelief. Brother, bofors, i don't know why you bother.

[JamesB]

Actually, let me get this straight, all we have been hearing now is how 110 stories of the towers fell at "free fall speed", "virtual free fall speed" or even my favorite "faster than the speed of gravity", and how that is impossible without the use of demolitions. So now is Bofors actually arguing that it is impossible for even one floor to collapse at "near free falls speed" even with the use of explosives?

Will you guys make up your mind already!!!

[CHF]

Can't wait to see the twoofers' reaction to this paper.

I suspect most of it will be along the lines of Bofor's in-depth analysis.

[Alferd_Packer]

I can't get it to download. Is it available anywhere else?

[T.A.M.]

I am waiting for the first "Seffen is second cousins with the gardener who tends the White House lawn...clearly govt disinfo."

TAM;)

[pomeroo]

My compliments to Dr. Seffen, for a straightforward paper and a closed-form solution. The guy even gives us a Lagrangian.

That's one more peer-reviewed paper for the good guys. The opposition still stands at, let's see... carry the two... zero.

Is there anyone out there who still thinks the Truth Movement hasn't forfeit the contest?


I've been trying to make the point that Griffin's retreat from the field of battle has nothing to do with me. It is a gesture of surrender that has everything to do with you (mostly) and, to a lesser degree, people like George Papcun and John Hotard. I don't say this to flatter you, but you have collapsed the house of cards. The near-total absence of criticism of your paper says it all. The fantasy movement is not fighting. They are screaming their mindless slogans to people who--they hope--don't know anything. They can't confront their opponents. You declared victory months ago, but now, thanks to Griffin, it's official.

[cmcaulif]

Ive only just skimmed the paper very briefly, but in his model with no mass shedding, there is an average acceleration of 1/2g for crush down, if I remember correctly, the BLGB model had average accelerations for WTC 1 and 2 that straddled this figure, although with 20% mass shedding.

I'll obviously have to give the paper a more thorough look but this seems like an interesting result.

[Apollo20]

Interesting if true.....

And interesting anyway!

But we do have the rather weak:

"It is likely that the uppermost parts of the WTC towers were falling freely due to an absence of column resistance in the first weakest storey..."

Where is the evidence for the truth of this statement?

[cmcaulif]

"Free-falling... over the height of just one storey..."

What a bunch of crap, that obviously did not happen and is not even possible with demolitions.

please look at figure 5....

[cmcaulif]

Greening (http://www.911myths.com/WTCREPORT.pdf) gives a value of tc for stage 1(crush down) as 11.6s and 9.7s for WTC 1 and 2 respectively. This is a pure momentum transfer model and ignores E1, the energy needed to destroy a floor.

Seffen's model gives crush down times of 8.3s and 7.3s when p*= 0, and values of around 12s for values of p* around 1. Considering the observed collapse times, that might be the final nail in the 'towers offered no resistance' coffin.

[cmcaulif]

Interesting if true.....

And interesting anyway!

But we do have the rather weak:

"It is likely that the uppermost parts of the WTC towers were falling freely due to an absence of column resistance in the first weakest storey..."

Where is the evidence for the truth of this statement?

It is a rather dubious statement, resistance certainly was not absent, even his own results show that!

[Apollo20]

Dr. Seffen is another engineer who is apparently so enamoured of his own model that he fails to make the distinction between a theoretical/calculated result and a real-world observation/measurement.

Thus on page 18 of his paper we read:

"The actual time for collapse of WTC 1 ranges from 8.3 seconds to 12.0 seconds, and for WTC2, from 7.3 seconds to 12.1 seconds..."

It turns out that these collapse times are not the observed times but the calculated times!

But then Dr. Seffen goes on to claim that his "actual" collapse times "embrace the observed period for both towers."

Where has anyone claimed to have observed a crush down time of 8.3 seconds for WTC 1 or 7.3 seconds for WTC 2?

This is complete BS and is being dishonest to say the least!

Engineers!!!!!!!!!!!!!!!!!!!!!!!

[Gravy]

I can't get it to download. Is it available anywhere else?I have a copy here (http://wtc7lies.googlepages.com/seffen_simple_analysis.pdf).

[ConspiRaider]

I am totally and completely unimpressed. Do we really need mathematicians to prove to us that the WTCs collapsed? No we do not. Hey! I think somebody should write a sonnet on how the WTCs collapsed!!! Because THAT really would convince me! Poemize the doubters into submission!!! Yeah, baby!

I suppose this Seffen dude has nothing better to do with his time?

1. The WTC was standing.
2. A big fuel-laden projectile crashed into it at high speed.
3. Extensive damage was caused to the structure on impact.
4. Further damage was caused by explosion and fire that raged unchecked.
5. The WTC collapsed.

How the hell difficult is that?!?

Mathematicians. Sheez. Keep them away from me. Get them to work designing an anti-gravity system or something practical. Such as determining the temperature and time factor involved in creating the perfect baked potato.

[Max Photon]

Dr. Seffen is another engineer who is apparently so enamoured of his own model that he fails to make the distinction between a theoretical/calculated result and a real-world observation/measurement.

[snip]




Apollo20,

There is a contemporary watercolorist named Frank Webb - a true hero of mine - who has taught art classes for eons.

Webb uses the beautiful phrase "the tyranny of the model" to describe the vice-like grip that the model has on some.

He says that in his experience there are those who can clearly differentiate between the model and the real world, and maintain the separation.

He says that there are others who simply cannot keep the two separate, and that they are impervious to being taught the difference.

The tyranny of the model grips the more uncreative scientists and engineers just the same.

Given that a model is just a metaphor, this is really saying that the afflicted cannot differentiate between metaphor and reality.

Having been a JREF for about 500 posts now, I see all the time those who confuse the NIST metaphor with reality.

(It always reminds me of Joseph Campbell's terrific title to one of his books: Metaphor as Myth and Religion.)

Got religion?

Max

ETA: For those who think the insights of a watercolorist are irrelevant to such hardcore sciencey stuff, remember, NIST - in using numerical methods to model the far-from-equilibrium dynamics of collapse initiation - is doing nothing more than painting portraits with noise.

* * *

[pomeroo]

Apollo20,

There is a contemporary watercolorist named Frank Webb - a true hero of mine - who has taught art classes for eons.

Webb uses the beautiful phrase "the tyranny of the model" to describe the vice-like grip that the model has on some.

He says that in his experience there are those who can clearly differentiate between the model and the real world, and maintain the separation.

He says that there are others who simply cannot keep the two separate, and that they are impervious to being taught the difference.

The tyranny of the model grips the more uncreative scientists and engineers just the same.

Given that a model is just a metaphor, this is really saying that the afflicted cannot differentiate between metaphor and reality.

Having been a JREF for about 500 posts now, I see all the time those who confuse the NIST metaphor with reality.

(It always reminds me of Joseph Campbell's terrific title to one of his books: Metaphor as Myth and Religion.)

Got religion?

Max

* * *



Some of us are dull-witted enough to wonder why a model that doesn't reflect reality is a model and not something else.

[R.Mackey]

Where has anyone claimed to have observed a crush down time of 8.3 seconds for WTC 1 or 7.3 seconds for WTC 2?

If I'm not mistaken, those times are the "free-fall" times from the impact zones of the two structures -- in other words, a theoretical lower limit.

I'm fairly certain nobody has claimed to have observed those times.

While the model is imperfect to be sure, it's still a useful exercise in my opinion. None of the models are perfect. It is nice to see that they reasonably agree even when built with different assumptions.

[Max Photon]

If I'm not mistaken, those times are the "free-fall" times from the impact zones of the two structures -- in other words, a theoretical lower limit.

I'm fairly certain nobody has claimed to have observed those times.

While the model is imperfect to be sure, it's still a useful exercise in my opinion. None of the models are perfect. It is nice to see that they reasonably agree even when built with different assumptions.



Well, they all have the same assumption - NOT CONTROLLED-DEMOLITION.


* * *

[pomeroo]

Well, they all have the same assumption - NOT CONTROLLED-DEMOLITION.


* * *


Ah, but if you assume controlled demolition, you will find exactly what you and all other fantasists have found: Absolutely nothing.

[Mangoose]

Where has anyone claimed to have observed a crush down time of 8.3 seconds for WTC 1 or 7.3 seconds for WTC 2?


The paper by Cherepanov also takes "free fall" for granted without making observations. A few months ago I posted on my observations of the collapse, doing what I've never seen anyone else doing, synchronizing the various videos with each other in order to develop a chronology of the collapse. It's not hard to do...anyone can do with a program like Premiere. I estimated that it took about 12 seconds for the first debris from the East Face of WTC2 to make land fall (counting from collapse initiation). But the second before the debris hit the ground, there were still columns standing at the northeast corner as high as the 78th floor (seemingly because the crushing upper block angled inward and missed the corner, as the ABC video recorded at 9:59:03 suggests). I find that remarkable, and it goes to show how complex the actual collapse was -- and only part of the collapse behavior was observable (much being hidden by the dust clouds). Then 14-16 seconds into the collapse, large chunks of debris were still falling as high as the 44th floor. And after most of the building had fallen to the ground, the lower part of the core still stood up to 25 seconds after the collapse started.

[Apollo20]

Thanks Mangoose, that is very interesting.

The other point to consider is that Seffen appears to be limiting his study to the initial crush down phase of the collapse, while ignoring crush up. Nevertheless, he compares his calculated collapse times to the TOTAL collapse times. Thus he compares apples with oranges.


Max:

Here is a wonderful quote from Albert Camus taken from his essay "The Myth of Sisyphus:

"And here are trees and I know their gnarled surface, water and I feel its taste. The scents of grass and stars at night, certain evenings when the heart relaxes - how shall I negate this world whose power and strength I feel? Yet all the knowledge on earth will give me nothing to assure me that this world is mine. You describe it to me and you teach me to classify it. You enumerate its laws and in my thirst for knowledge I admit that they are true. You take apart its mechanism and my hope increases. At the final stage you teach me that this wonderous and multicolored universe can be reduced to the electron. All this is good and I wait for you to continue. But you tell me of an invisible planetary system in which electrons gravitate around a nucleus. You explain this world to me with an image. I realize then that you have been reduced to poetry; I shall never know. Have I the time to become indignant? You have already changed theories...."

[T.A.M.]

Interesting if true.....

And interesting anyway!

But we do have the rather weak:

"It is likely that the uppermost parts of the WTC towers were falling freely due to an absence of column resistance in the first weakest storey..."

Where is the evidence for the truth of this statement?

Did Bazant & Zhou not state/assume the same thing in their original paper on the WTC collapse? (IIRC)


The energy dissipation, particularly that due to the inelastic deformation of columns during the initial drop of the upper part, may be neglected, i.e., the upper part may be assumed to move through distance h almost in a free fall (indeed, the energy dissipated in the columns during the fall is at most equal to 2πX the yield moment of columns, X the number of columns, which is found to be only about 12% of the gravitational potential energy release if the columns were cold, and much less than that at 800°C).

http://www.911-strike.com/BazantZhou.htm

TAM:)

TAM:)

[Apollo20]

TAM:

You are correct!

I assumed it too in my paper on the WTC collapse times.

However, it remains an unproven hypothesis.... and the tipping of the upper section is ignored in such a model.

[Max Photon]

Max:

Here is a wonderful quote from Albert Camus taken from his essay "The Myth of Sisyphus:

"And here are trees and I know their gnarled surface, water and I feel its taste. The scents of grass and stars at night, certain evenings when the heart relaxes - how shall I negate this world whose power and strength I feel? Yet all the knowledge on earth will give me nothing to assure me that this world is mine. You describe it to me and you teach me to classify it. You enumerate its laws and in my thirst for knowledge I admit that they are true. You take apart its mechanism and my hope increases. At the final stage you teach me that this wonderous and multicolored universe can be reduced to the electron. All this is good and I wait for you to continue. But you tell me of an invisible planetary system in which electrons gravitate around a nucleus. You explain this world to me with an image. I realize then that you have been reduced to poetry; I shall never know. Have I the time to become indignant? You have already changed theories...."





Sorry Apollo, I was busy pushing peanuts up Everest with my nose.

What was that again?


Maxyphus

* * *

[T.A.M.]

TAM:

You are correct!

I assumed it too in my paper on the WTC collapse times.

However, it remains an unproven hypothesis.... and the tipping of the upper section is ignored in such a model.

I believe the tipping, in part, was ignored do the complexity that would be involved in modeling it, and the fact that assuming a symmetrical, "non-tipping" scenario would be the most optimistic in terms of the structure being able to keep from collapsing.

In other words, given that in theory a "tipping" model would be worse in terms of global collapse, than a "non-tipping" one, they used the "non-tipping" scenario, and this still resulted in a global collapse.


For our purpose, we may assume that all the impact forces go into the columns and are distributed among them equally. Unlikely though such a distribution may be, it is nevertheless the most optimistic hypothesis to make because the resistance of the building to the impact is, for such a distribution, the highest. If the building is found to fail under a uniform distribution of the impact forces, it would fail under any other distribution. According to this hypothesis, one may estimate that C 71 GN/m (due to unavailability of precise data, an approximate design of column cross sections had to be carried out for this purpose).


The basic question to answer is: Can the fall of the upper part be arrested by energy dissipation during plastic buckling which follows the initial elastic deformation? Many plastic failure mechanisms could be considered, for example: (a) the columns of the underlying floor buckle locally (Fig. 1, stage 2); (b) the floor-supporting trusses are sheared off at the connections to the framed tube and the core columns and fall down within the tube, depriving the core columns and the framed tube of lateral support, and thus promoting buckling of the core columns and the framed tube under vertical compression (Fig. 1, stage 4, Fig. 2c); or (c) the upper part is partly wedged within the emptied framed tube of the lower part, pushing the walls of the framed tube apart (Fig. 1, stage 5). Although each of these mechanism can be shown to lead to total collapse, a combination of the last two seems more realistic (the reason: multi-story pieces of the framed tube, with nearly straight boundaries apparently corresponding to plastic hinge lines causing buckles on the framed tube wall, were photographed falling down; see, e.g., Engineering 2001, American 2001).

As well, in their appendix II, they go into why they neglected "tilting".

http://www.911-strike.com/BazantZhou.htm

I will admit that with my 1st-2nd year college physics of 15 years ago, some of the paper was a little over my head, so I could be wrong on the above.

TAM:)

[cmcaulif]

TAM:

You are correct!

I assumed it too in my paper on the WTC collapse times.

However, it remains an unproven hypothesis.... and the tipping of the upper section is ignored in such a model.

The effects of tipping on resistance seems to be easier to visualize with regards to this model, compared to others. When he describes his 'three idealized deformation stages' on page 5, (a) and (b) deal with buckling and post buckling, and (c) deals with floors striking one another. It seems that, as he notes, (a) and (b) are from the Bazant and Zhou model, in which case I would assume that he is relying on columns to strike axially, as in B&Z, which tipping would certainly prevent from happening. Although when he mentions (c), and 'propagating instability' this clearly does not rely on columns striking axially, and tipping would seem to cause higher instability in some parts of the structure than others, which I imagine would lead to higher instability overall.

I suppose there is no way to quantify any of it without calculation though.