RFC: Bazant and Zhou Simple Analysis refuted

[GregoryUrich]

I have recalculated Bazant and Zhou's overload ratio with the result that progressive collapse is not predicted by the model. Please see the article:

http://www.cool-places.0catch.com/docs/Overload.pdf

Any constructive comments would be appreciated.

[T.A.M.]

here is a constructive comment...

Send it to Bazant and Zhou, and ask them for critique, and a reply to your paper.

TAM:)

[Gravy]

Did you solicit comments from Bazant?

[GregoryUrich]

Did you solicit comments from Bazant?

Gravy and TAM,

The engineers here can help me find any glaring mistakes before I bother the big boys.

[T.A.M.]

Fair enough, I will leave it to the Engineers here, and then look forward to reading the reply you get from B & Z when all is said in done...good luck.

TAM:)

[Apollo20]

Gregory:

I wonder if a mere chemist could pass comment?

On the other hand.......

Na,

let's leave it to the engineers!

[JamesB]

Gregory:

I wonder if a mere chemist could pass comment?



It has never stopped Kevin Ryan...

[Apollo20]

O.K, I should note that GU's value for L is incorrect, as is his value of A. Hence his value for k is wrong.

You need to consider where the spring begins, and it is not at floor 103 when the spring was broken at floor 95...............

[rwguinn]

I have recalculated Bazant and Zhou's overload ratio with the result that progressive collapse is not predicted by the model. Please see the article:

http://www.cool-places.0catch.com/docs/Overload.pdf

Any constructive comments would be appreciated.

Oh, well done. You have a building with a 46Hz longitudinal mode. Home nobody did any joggine in there...or fast walking.

and a static deflection of almost .2 inches at the floor 97/98 interface.
That translates (simplifying as you did) to nearly 20 inches at ground level.
You think so? That, me lad, is a very high strain that the foundation has to take up...

Calculating the stiffness by reducing to area of the verticals is ignoring all the work the designers went to in order to make the actual structure stiffer than its component parts.

ETA: And your assumption 4 is incorrect.

[Newtons Bit]

I have recalculated Bazant and Zhou's overload ratio with the result that progressive collapse is not predicted by the model. Please see the article:

http://www.cool-places.0catch.com/docs/Overload.pdf

Any constructive comments would be appreciated.

Greg, what are you doing? Your paper was almost right before you changed it. You just added crap to give it a conclusion that you wanted.

The equation that you used is to determine the overload ratio of a mass impacting a spring. And then you go ahead and subtract out an event that happens after the peak impact load, why? The plastic energy E-plastic, dissipated by the columns happens AFTER the peak load is applied to them. You can't subtract the energy required to fail the columns before the mass even impacts the columns. This is the ******** that I'd expect Gordon Ross to perform, not you.

After your paper on mass and pe for the WTC I thought that you weren't a religious truther - dedicated to proving conclusion regardless of whether or not you have to fake the math to do it. Now I'm not so sure and it makes me sick. :(

[rwguinn]

Greg, what are you doing? Your paper was almost right before you changed it. You just added crap to give it a conclusion that you wanted.

The equation that you used is to determine the overload ratio of a mass impacting a spring. And then you go ahead and subtract out an event that happens after the peak impact load, why? The plastic energy E-plastic, dissipated by the columns happens AFTER the peak load is applied to them. You can't subtract the energy required to fail the columns before the mass even impacts the columns. This is the ******** that I'd expect Gordon Ross to perform, not you.

After your paper on mass and pe for the WTC I thought that you weren't a religious truther - dedicated to proving conclusion regardless of whether or not you have to fake the math to do it. Now I'm not so sure and it makes me sick. :(

You got further into it than I did--I looked at the assumptions and croaked...
Failure occurs at YIELD. That's the start. Once it's bent, it is, to all intents and purposes, busted, broken, kaput.

[cmcaulif]

I have recalculated Bazant and Zhou's overload ratio with the result that progressive collapse is not predicted by the model. Please see the article:

http://www.cool-places.0catch.com/docs/Overload.pdf

Any constructive comments would be appreciated.

At no point did Bazant and Zhou claim that the overload ratio would predict collapse or arrest. It is merely a basic estimate of the overload ratio based on a spring with mass collision equation derived by the authors and also found in mechanics of solids texts.

I really cant think of any way to use this equation to predict collapse or arrest either, since in order to use it, the assumption of evenly distributed load has been made, and the safety factors for the perimeter and core columns were different if I recall correctly.

Equation 3 is what you want for their prediction on collapse/arrest.

[metamars]

I have recalculated Bazant and Zhou's overload ratio with the result that progressive collapse is not predicted by the model. Please see the article:

http://www.cool-places.0catch.com/docs/Overload.pdf

Any constructive comments would be appreciated.

Eventually, all simple models will have to be compared to fully dynamic ones, which employ calculus throughout, to know where and by how much they are not accurate.

I'm going to be busy for the next 3 weeks studying for an exam. If I don't start a new job by then, I'll try and get into calculating something exact. One paper I'll check out I just ran into today:

Buckling of columns under variably distributed axial loads.
Vaziri, H H; Xie, J
Computers and Structures. Vol. 45, no. 3, pp. 505-509. 1992

A new numerical model for analyzing the buckling of columns with variably distributed axial loads is proposed in this paper. The presented method transforms the traditional eigenvalue problem into an initial boundary value problem which can be solved by numerical integrations. The buckling load is determined by a proposed two-step iterative procedure. Because of its concise and easy-to-implement form, the proposed method can be coded and used for analysis with a minimum requirement for the in-core memory storage of a computer. The proposed model is verified for a column with uniformly distributed axial loads, and the application of the method is demonstrated by analyzing columns with variably distributed axial loads and columns with varying cross-sections. Some interesting conclusions are made.

Descriptors: Buckling; Mathematical models; Eigenvalues and eigenfunctions; Structural analysis; Boundary value problems; Integration; Computer applications

[metamars]

Eventually, all simple models will have to be compared to fully dynamic ones, which employ calculus throughout, to know where and by how much they are not accurate.


Eventually, all fully dynamic models will have to be compared with experiments, to know where and by how much they are not accurate!

[AZCat]

Eventually, all fully dynamic models will have to be compared with experiments, to know where and by how much they are not accurate!

Some of that has been done already. The 1982 C.I.D. (http://en.wikipedia.org/wiki/Controlled_impact_demonstration), for example, was run partly to validate some of the FEA methods used in later software tools (and the NIST investigation, I think). You'd have to ask the structural guys here for building examples, but the NIST BFRL (http://www.bfrl.nist.gov/) has been running (and funding grants for) experiments for some time now - it might not be a bad idea to check their site for articles.

[R.Mackey]

For those of you beating up on Gregory, please be civil... I find problems with his paper too, but so what? It's properly posed, so we have to think about the replies, and we'll learn something. This alone sets it apart from the vast majority of Truther idiocy, about which one can only say, "huh??"

Anyway, as others have noted, the spring constant computed here is not supportable. I don't see any way for the whole 110 stories (or even the whole 90-odd stories of the "lower block") to participate elastically, let alone in compression.

So what is the correct value of the spring constant? I'd be tempted to hand-wave and say that we should only treat a column down to the next splice, i.e. three stories worth, but this is probably wrong too.

B&Z's estimate of C is also hand-wavey, of course. However, they choose what they call an optimistic value, i.e. all of the columns participate equally in opposing the collapse. I'm extremely reluctant to accept an order-of-magnitude adjustment to this value without more careful thought.

Also, regarding Ultimate Strength, what's computed in Gregory's writeup is the ultimate compressive strength, not the ultimate buckling strength, so it's overestimated. (Yes, B&Z's estimate is coarse and not quite correct either. Remember their paper came out in three days and with few actual WTC design details.)

Lastly, even if we accepted all of the calculations here, it should be noted that B&Z computed a generous estimate by discounting the effects of fracture, etc. So a result showing the "corrected" energy fraction was 0.81 instead of > 1 would also not guarantee collapse arrest, though it would prove the B&Z model was oversimplified, and a more thorough analysis required to answer the question once and for all.

Thoughts?

[Apollo20]

Gregory Urich:

And continuing the discussion of your calculation of k: You cannot expect to get a meaningful value of k by using "a single element with a combined cross sectional area of all the columns", and plugging the A value into k=AE/L. This ignores the role of the trusses, the visco-elastic dampers and the "tube within a tube" structure of the building...... That is why the formula for the free vibration of the tower:

Vibrational frequency (in rads/s) = Sqrt {k/M}

where M is the mass of the tower,

simply does not work for Bazant's, (or your), value of k.

[rwguinn]

I am not really sure what point 1 (Paragraph 4) regarding internal strain energy within the upper striuucture itself has to do with external effects.

As I said--I couldn't get past the assumptions. Assuming the entire height of the building for AE/L totally ignores all the work the designers did--and if we use that value, then the buckling calcs will likely show that the building collapses at 1 g, static. (I claim no buckling expertise, here)

Additionally, E is the slope of the stress-strain curve from 0 strain to yield--not to ultimate. That value is 29.9e6 lbf/in^2.
For steel, the stress-strain curve sharply drops at yield, and then is very nearly flat (orders of magnitude lower than 29.9e6) in comparison to the 0-yield value)
If you wish to average, be consistent. The E for steel will make rubber look stout at that slope.
It is always best to keep things linear. Once the material reaches yield, everything becomes non-linear--material, geometry--all of it. Load paths are also no longer valid--they have to be revised.

In short, using a linear value for ultimate leads you to false conclusions.

[Major_Tom]

rwguinn comments:

Calculating the stiffness by reducing to area of the verticals is ignoring all the work the designers went to in order to make the actual structure stiffer than its component parts.

Agreed. How did Bazant calculate the same quantity? The same way, no?



cmcaulif notes:

At no point did Bazant and Zhou claim that the overload ratio would predict collapse or arrest. It is merely a basic estimate of the overload ratio based on a spring with mass collision equation derived by the authors and also found in mechanics of solids texts.

I really cant think of any way to use this equation to predict collapse or arrest either, since in order to use it, the assumption of evenly distributed load has been made, and the safety factors for the perimeter and core columns were different if I recall correctly.


Exactly. I'm surprised more people can't see that.

There are rather absurd assumptions which go into equating the gained kinetic energy of the upper "block" with the blow the lower columns receive, as if a 100% transmittance of energy isn't just a "cartoon".

Many assumtions IMPLICIT in the equations that can only exist in a place called "Theoryland".

[cmcaulif]

Exactly. I'm surprised more people can't see that.

There are rather absurd assumptions which go into equating the gained kinetic energy of the upper "block" with the blow the lower columns receive, as if a 100% transmittance of energy isn't just a "cartoon".

Many assumtions IMPLICIT in the equations that can only exist in a place called "Theoryland".

I'm not sure what you mean by this MT. Bazant's equation is valid because it satisfies conservation of energy (kinetic energy of the mass turned completely into strain energy of the spring at the max deflection). It is however a massive simplification of a chaotic event.

I really don't think a whole lot can be gleaned from the equation in terms of predicting arrest though.

[cmcaulif]

Lastly, even if we accepted all of the calculations here, it should be noted that B&Z computed a generous estimate by discounting the effects of fracture, etc. So a result showing the "corrected" energy fraction was 0.81 instead of > 1 would also not guarantee collapse arrest, though it would prove the B&Z model was oversimplified, and a more thorough analysis required to answer the question once and for all.

Thoughts?

I don't think using the overload factor would be appropriate for predicting arrest or collaspe because factors of safety would need to be taken into account. It would be much better to use an equation like Bazant and Zhou equation three, in which no safety factor is needed, and modify the equation to include the effects of other limit states such as fracture, or even possibly local stability modes of failure like web buckling, as well as elastic energy dissipation.

However, from what I have been able to gather from poking through a textbook by Bazant and another on stability of structures is that the approach taken in Bazant and Verdure may be the most complete that has been produced so far, in which the load-deflection diagrams for a story of the WTC are calculated, which allows for the snapthrough load to be determined, as well as the work done by the structure. This is similar to Seffen's approach and Maxwell construction as well.

[Major_Tom]

I'm not sure what you mean by this MT. Bazant's equation is valid because it satisfies conservation of energy (kinetic energy of the mass turned completely into strain energy of the spring at the max deflection).

True, but the implicit assumtion is that all of that energy is then transferred to the ends of the javelin-like columns of the lower section. Over and over.

Equation means "to equate". Equating the gained kinetic energy with the blow the lower columns receive is an assumption to the extreme.

It assumed direct column end-to-column end contact over and over again.

Assuming direct column end-to-column end contact after the first "buckling" or "hinging" is quite an assumtion. To assume that this happens over and over again seems ridiculous.


And besides, the entire spring argument loses all meaning when we consider that the large, large majority of core box columns seen in the rubble were very straight and clearly broke into smaller sections by cleanly breaking along their original column-to-column welds, manifesting no plastic, permanent destortion at all?

What meaning does the spring argument have if your "spring" breaks up cleanly into 38 foot sections before your spring equations even apply?

What meaning does the entire approach have if your "spring" has welds that give?

[Heiwa]

Excellent paper in many respects.

In my view the spring constant should be variable - or better - the tower below the initiation zone - should be represented by several springs with different spring constants - as a function of the total cross sectional area of the tower at the relevant level. You only need to make the tower below 10 springs.

Then we find that the 'softest' spring is located just below the initiation zone and that anything dropping on it - e.g. the tower above - will just bounce off!! All kinetic energy from above (it is easy to calculate) is evidently absorbed by the top spring as compression that then pushes some of the energy down to the spring below and the rest is used to push back the tower above.

Furthermore - the tower above is also a spring! So when it drops down and hits the top spring below, it also compresses itself and loses a lot of energy in that compression.

It will be a very soft collision when these two parts meet - and no global collapse of any kind, e.g. what you see on all videos of the collapse where 100X the kinetic energy available from the tower above makes the whole tower explode like a bomb was dropped on it.

Remember that when a spring breaks - it only breaks in one location. Not in 1000's of pieces.

[Dave Rogers]

Not an engineer, but a physicist, so I'm not claiming any particular expertise, but one thing strikes me as surprising here. The static loading of the top 13 storeys is 5.7MN, whereas you give the ultimate strength of the columns as 1.67GN. Is a safety factor of 290 really needed? This seems to suggest that the support columns were over-engineered by a factor of about 100, which doesn't look economically sound to me. If I got such an unlikely result I'd be tempted to re-examine my starting assumptions.

Dave

[GregoryUrich]

O.K, I should note that GU's value for L is incorrect, as is his value of A. Hence his value for k is wrong.

You need to consider where the spring begins, and it is not at floor 103 when the spring was broken at floor 95...............

From the basement Apollo. The initial collapse was between 97-98. So 97+6=103. I would agree the spring was damaged in the impact area but not broken.

[GregoryUrich]

Greg, what are you doing? Your paper was almost right before you changed it. You just added crap to give it a conclusion that you wanted.

The equation that you used is to determine the overload ratio of a mass impacting a spring. And then you go ahead and subtract out an event that happens after the peak impact load, why? The plastic energy E-plastic, dissipated by the columns happens AFTER the peak load is applied to them. You can't subtract the energy required to fail the columns before the mass even impacts the columns. This is the ******** that I'd expect Gordon Ross to perform, not you.

After your paper on mass and pe for the WTC I thought that you weren't a religious truther - dedicated to proving conclusion regardless of whether or not you have to fake the math to do it. Now I'm not so sure and it makes me sick. :(

Horsey dung!

The E plastic is during the initial collapse. That portion of the potential energy must be removed before the first impact. Bazant hand-waved this away as inconsequential. Oops!

I not sure what to make of the other bogus accusations.

[Dave Rogers]

True, but the implicit assumtion is that all of that energy is then transferred to the ends of the javelin-like columns of the lower section. Over and over.

Equation means "to equate". Equating the gained kinetic energy with the blow the lower columns receive is an assumption to the extreme.

It assumed direct column end-to-column end contact over and over again.

Assuming direct column end-to-column end contact after the first "buckling" or "hinging" is quite an assumtion. To assume that this happens over and over again seems ridiculous.

I suspect most people who've examined the situation really closely would agree with you. However, all that actually means is that Bazant's model goes to great lengths to assume that the impulse delivered to the lower structure is done so in such a way as to maximise the lower structure's ability to resist that impulse, i.e. axially on the columns. In a more realistic scenario, the columns impact on the floors, which are quite incapable of bearing even the static loadings, and will therefore collapse progressively. Without the cross-bracing of the floors, the columns are too slender to stand independently. Therefore, column-on-floor impact is energetically greatly in favour of collapse propagation compared to column-on-column impact.


And besides, the entire spring argument loses all meaning when we consider that the large, large majority of core box columns seen in the rubble were very straight and clearly broke into smaller sections by cleanly breaking along their original column-to-column welds, manifesting no plastic, permanent destortion at all?

What meaning does the spring argument have if your "spring" breaks up cleanly into 38 foot sections before your spring equations even apply?

What meaning does the entire approach have if your "spring" has welds that give?

It means that the "spring" collapses far more easily than Bazant predicts, because instead of the fracture energy for four plastic hinges per storey we only have to consider the fracture energy for a single weld every three storeys. Again, this is energetically greatly in favour of collapse propagation.

As Gregory very honestly admits, even if all his calculations are correct here (and I'm not entirely sure that's the case, as I've said), collapse progression is not disproved; it is simply shown that in Bazant's highly unrealistic simplification, which is strongly biased against collapse, then collapse has not been shown to be inevitable; and even in that scenario the force only falls short of that required by about 10%.

Dave

[GregoryUrich]

Oh, well done. You have a building with a 46Hz longitudinal mode. Home nobody did any joggine in there...or fast walking.

and a static deflection of almost .2 inches at the floor 97/98 interface.
That translates (simplifying as you did) to nearly 20 inches at ground level.
You think so? That, me lad, is a very high strain that the foundation has to take up...

Calculating the stiffness by reducing to area of the verticals is ignoring all the work the designers went to in order to make the actual structure stiffer than its component parts.

ETA: And your assumption 4 is incorrect.

I agree that the actual structure is stiffer in terms of resisting buckling and overturning moments but is the elastic energy really affected by the horizontal members and Vierendeel trusses?

I don't see how longitudinal mode has anything to do with axial compression. My simplification only needs to be correct in terms of absorbing energy.

Newtons Bit did a more correct calculation of the spring constant and got 10 GN m which is very close to mine. I don't think it will affect the result significantly but of course I will check. Could you post that Newton?

[GregoryUrich]

At no point did Bazant and Zhou claim that the overload ratio would predict collapse or arrest. It is merely a basic estimate of the overload ratio based on a spring with mass collision equation derived by the authors and also found in mechanics of solids texts.

I really cant think of any way to use this equation to predict collapse or arrest either, since in order to use it, the assumption of evenly distributed load has been made, and the safety factors for the perimeter and core columns were different if I recall correctly.

Equation 3 is what you want for their prediction on collapse/arrest.

If you follow their argument, you can't get to equation 3 without failure at the first impact. The additional mgh never comes into play!

[The Doc]

I read some of this thread and now I feel stupid :(

Kudos to all of you. You're doing work that persons such as myself would never be able to do.

[GregoryUrich]

I am not really sure what point 1 (Paragraph 4) regarding internal strain energy within the upper striuucture itself has to do with external effects.

As I said--I couldn't get past the assumptions. Assuming the entire height of the building for AE/L totally ignores all the work the designers did--and if we use that value, then the buckling calcs will likely show that the building collapses at 1 g, static. (I claim no buckling expertise, here)

Additionally, E is the slope of the stress-strain curve from 0 strain to yield--not to ultimate. That value is 29.9e6 lbf/in^2.
For steel, the stress-strain curve sharply drops at yield, and then is very nearly flat (orders of magnitude lower than 29.9e6) in comparison to the 0-yield value)
If you wish to average, be consistent. The E for steel will make rubber look stout at that slope.
It is always best to keep things linear. Once the material reaches yield, everything becomes non-linear--material, geometry--all of it. Load paths are also no longer valid--they have to be revised.

In short, using a linear value for ultimate leads you to false conclusions.

Regarding point 1, the upper part is a spring also and absorbs energy during the collision. B & Z don't take this into account as I am trying to do. I am aware I am oversimplifying in that the upper spring will absorb less energy. Then again I am aware that all of the energy will not be available at the impact boundary.

This brings up another issue. Does anyone know how to establish the portion of the kinetic energy available at the impact boundary?

I understand your point regarding yield stress vs ultimate stress.

[GregoryUrich]

Not an engineer, but a physicist, so I'm not claiming any particular expertise, but one thing strikes me as surprising here. The static loading of the top 13 storeys is 5.7MN, whereas you give the ultimate strength of the columns as 1.67GN. Is a safety factor of 290 really needed? This seems to suggest that the support columns were over-engineered by a factor of about 100, which doesn't look economically sound to me. If I got such an unlikely result I'd be tempted to re-examine my starting assumptions.

Dave

F = mg; 32.8 x 10^6 x 9.81 = 0.321 GN

I think the safety factor is based on design load and ultimate strength. NIST refers to the "ultimate strength method". This is not necessarily based on the ultimate strength of the material. Can someone enlighten us here?

As Rwguinn points out, I should be using the yield strength. In that case the safety factor falls in the range 2-3.

[Heiwa]

Not an engineer, but a physicist, so I'm not claiming any particular expertise, but one thing strikes me as surprising here. The static loading of the top 13 storeys is 5.7MN, whereas you give the ultimate strength of the columns as 1.67GN. Is a safety factor of 290 really needed? This seems to suggest that the support columns were over-engineered by a factor of about 100, which doesn't look economically sound to me. If I got such an unlikely result I'd be tempted to re-examine my starting assumptions.

Dave

No - if the top part weighs 32 800 tonnes = 0.328 GN (with g = 10) and the cross sectional area of all columns at the initiation zone is 5.6 m² you get the static stress to be 58.6 MPa that is about 24% of the yield stress (248 MPa) or a FoS (up to yield) of 4. Standard design.
The ultimate strength of the 5.6 m² of columns is probably decided by buckling at yield stress, thus 1.39 GN (or 1.67 GN if yield is at 298 MPa).
If yield is at 298 MPa the static stresses are only 20% of yield and FoS is 5.
Quite strong structure, actually. No way that such strong (low stressed) structure will suddenly collapse and shatter in 1000 000's of parts when some sub-parts fail for any reason. It is as simple as that.

[Dave Rogers]

F = mg; 32.8 x 10^6 x 9.81 = 0.321 GN

Must have picked up the wrong mass from somewhere, sorry. Stundie nomination, anyone?

As Rwguinn points out, I should be using the yield strength. In that case the safety factor falls in the range 2-3.

In which case, doesn't that mean that you get a ratio of 1.35-2, hence the collapse propagates?

Dave

[GregoryUrich]

For those of you beating up on Gregory, please be civil... I find problems with his paper too, but so what? It's properly posed, so we have to think about the replies, and we'll learn something. This alone sets it apart from the vast majority of Truther idiocy, about which one can only say, "huh??"

Anyway, as others have noted, the spring constant computed here is not supportable. I don't see any way for the whole 110 stories (or even the whole 90-odd stories of the "lower block") to participate elastically, let alone in compression.

So what is the correct value of the spring constant? I'd be tempted to hand-wave and say that we should only treat a column down to the next splice, i.e. three stories worth, but this is probably wrong too.

B&Z's estimate of C is also hand-wavey, of course. However, they choose what they call an optimistic value, i.e. all of the columns participate equally in opposing the collapse. I'm extremely reluctant to accept an order-of-magnitude adjustment to this value without more careful thought.

Also, regarding Ultimate Strength, what's computed in Gregory's writeup is the ultimate compressive strength, not the ultimate buckling strength, so it's overestimated. (Yes, B&Z's estimate is coarse and not quite correct either. Remember their paper came out in three days and with few actual WTC design details.)

Lastly, even if we accepted all of the calculations here, it should be noted that B&Z computed a generous estimate by discounting the effects of fracture, etc. So a result showing the "corrected" energy fraction was 0.81 instead of > 1 would also not guarantee collapse arrest, though it would prove the B&Z model was oversimplified, and a more thorough analysis required to answer the question once and for all.

Thoughts?

I would guess B & Z used around 10 floors in calculating "C" as I checked it against the actual cross-sectional area.

Your last point is essentially what I say in the conclusion.

[GregoryUrich]

Must have picked up the wrong mass from somewhere, sorry. Stundie nomination, anyone?



In which case, doesn't that mean that you get a ratio of 1.35-2, hence the collapse propagates?

Dave

There are still other issues, but ignoring them, yes.

ETA: Ratio = 1.29 actually

[einsteen]

This strain stuff etc is indeed specialists work, I even didn't know (until Apollo20 told) that the crushing force of a plane's fuselage goes with the square root of the radius. But from pure energy equations etc also something can be said about the "overdesign". It is interesting for example that if you take David B. Benson's estimation of the average resistive force in the beginning (or the energy value E1 divided by h in the discrete model) that this is roughly 1/3 of the static force, i.e. the force to keep the top section in the air. In reality the force is not constant but will grow linearly in the beginning and finally give the complex stress-strain curve. The integration of that force over the distance should equal that same value E1. If you assume (for simplicity) that is a simple linear function that drops to zero after a maximum value (a saw-tooth function) on a small interval [0,a], 0<a<h then you could theoretically determine the maximum value.

[metamars]

Horsey dung!

The E plastic is during the initial collapse.

That portion of the potential energy must be removed before the first impact. Bazant hand-waved this away as inconsequential. Oops!



I don't know what you mean. In BZ, plastic hinge rotations occur as a result of impact. During the assumed free fall through h, impact has not occurred, yet.

A fully dynamic analysis will utilize calculus to make dynamical evolution mathematically precise. If you study, e.g., the Ari-Gur/Singer paper, the question of subtracting a net plastic energy before or after a net elastic energy doesn't arise. Not in a simple way such as being discussed, anyway.

From their experimental results, seen in Fig. 2a, http://metamars.i8.com/ , at the particular spot in the rod that measurements were made, we can see that an elastic deformation and plastic deformation only overlap for about 1.5 msec. The elastic pulse preceeds the plastic pulse by about .5 msec. So, at least for the Ari-Gur/Singer scenario, it looks like you can say that, in some sense, you can subtract a portion of elastic energy before plastic energy.

After the elastic compressive pulse has passed, the plastic flow continues, along with it's associated energy sink.

I interpret this all as meaning that during collision, locally speaking, you can have plastic deformation simultaneously with an elastic overload condition, or without it, but immediately following.

Even if you can integrate respective energy sinks over all time and over all length of the struck rod/column, I don't think that will tell us what we want to know.


The real questions for axial strike WTC models, such as BZ, are
1) should plastic deformation have arisen, at all?
2) if so, was the plastic deformation sufficient to fail the columns?


Your calculations, both the new and previous one, are intriguing because the overload ratios you calculate are close to 1. However, in either case, we have to take this as suggestive, and look to a deeper theory.

It'd be nice to have Ari-Gur and Singer participate in these discussions....

[einsteen]

Although I didn't read his paper I already think I know what he means

A free fall of one story leads to

E_kin=(1/2)Mv^2=Mgh [v=sqrt(2*g*h)]

But I think he means that E1 should be subtracted in the beginning, or maybe not E1 but E1' because that story was much weaker than the 'intact' stories below, that leads to a velocity not sqrt(2*g*h), but

sqrt(2*[g*h-E1'/M])

Or simply not a drop in vacuum but a drop in a demolished story. That is correct of course. But it doesn't matter, 8.5 m/s or 7.3 m/s

[GregoryUrich]

I don't know what you mean. In BZ, plastic hinge rotations occur as a result of impact. During the assumed free fall through h, impact has not occurred, yet.

A fully dynamic analysis will utilize calculus to make dynamical evolution mathematically precise. If you study, e.g., the Ari-Gur/Singer paper, the question of subtracting a net plastic energy before or after a net elastic energy doesn't arise. Not in a simple way such as being discussed, anyway.

From their experimental results, seen in Fig. 2a, http://metamars.i8.com/ , at the particular spot in the rod that measurements were made, we can see that an elastic deformation and plastic deformation only overlap for about 1.5 msec. The elastic pulse preceeds the plastic pulse by about .5 msec. So, at least for the Ari-Gur/Singer scenario, it looks like you can say that, in some sense, you can subtract a portion of elastic energy before plastic energy.

After the elastic compressive pulse has passed, the plastic flow continues, along with it's associated energy sink.

I interpret this all as meaning that during collision, locally speaking, you can have plastic deformation simultaneously with an elastic overload condition, or without it, but immediately following.

Even if you can integrate respective energy sinks over all time and over all length of the struck rod/column, I don't think that will tell us what we want to know.


The real questions for axial strike WTC models, such as BZ, are
1) should plastic deformation have arisen, at all?
2) if so, was the plastic deformation sufficient to fail the columns?


Your calculations, both the new and previous one, are intriguing because the overload ratios you calculate are close to 1. However, in either case, we have to take this as suggestive, and look to a deeper theory.

It'd be nice to have Ari-Gur and Singer participate in these discussions....

The freefall assumption is false. I.e. the plastic hinges will arise in the first columns to fail. That is what I am trying to take account of. B and Z state that this energy is insignificant due to damage and heating, and therefore a freefall is assumed. I show that there is very little damage at the initial collapse floors (97-98) and that heating cannot be considered a factor based on the evidence.

I agree that a full dynamic analysis is required. This is what NIST has done but we have no way of examining their method.

[Max Photon]

I read some of this thread and now I feel stupid :(

Kudos to all of you. You're doing work that persons such as myself would never be able to do.


Doc, understanding is a strange thing - when you understand something, it seems infinitely easy, and when you don't, it seems infinitely difficult.

I am sure if someone oriented you, you'd probably be shrieking like 2nd grader at recess as you let in how simple - how simplified - how over-simplified - all this really is.


Doc, I'll tell you where I'm lost. I for the life of me can fathom why everyone is so interested in collapse progression.

The interesting question - and the important question from a 'whodunit" perspective - is what initiated collapse.

If collapse progression is an unquenchable fetish, then at a minimum recognize that output from WHAT INITIATED COLLAPSE? is input for HOW DID COLLAPSE PROGRESS?

If you think collapse initiation was not catalyzed, and it was, then the input for your collapse progression modeling will likely be incorrect.

Studying collapse progression before resolving collapse initiation is putting the cart before the horse.

Photon Max

[beachnut]

I have recalculated Bazant and Zhou's overload ratio with the result that progressive collapse is not predicted by the model. Please see the article:

http://www.cool-places.0catch.com/docs/Overload.pdf

Any constructive comments would be appreciated.
You can't prove the WTC can not fail due to fire after the impact. You could live up to your membership in 9/11 truth and help with the petition of truth you signed.

Oops, you have made over 6, errors. Good luck next time. You do understand this is a model. Which paper? Oh, the one they did right after the WTC fell. Oh, then you can do it again and show how the concept is correct since the building did fall. If not you are wasting your time.

As seen you have not proved anything about 9/11, you are just attacking a model. It would be better to submit your own model. But I know you are trying to prove the WTC can not fail due to impact and fire alone. When will you prove the silent explosives and or the nut case thermite idea is real? Good work, you are attacking a model; If I was doing this I would just produce the work you really want, your so called paper to prove the WTC can not fail; like Ross. Ross was dead wrong.

So when will your final paper be done?

Which WTC does not fail? What about the other one? 3 days, 6 years, so?

You need to get Heiwa and Max Photo to be your helpers on this; Jones and his thermite can help, and Tony, he is an expert at research. With all that help you will be on your way. When you fix a few errors your paper will be a very good paper on a model about the WTC. Good luck again. (have you published this in the thermite inspired Journal of Truthyness yet?

I am sorry, but...

[metamars]

The freefall assumption is false.

Well, yes it is. I usually think in terms of refuting the BZ paper via showing that, even accepting this assumption (as well as the assumption of an axial strike), that collapse would be arrested.

In order to do so definitively, at the very least one will have to rely on quantitative research which existed well before 911, and solve numerically.

I think everybody knows that both the assumption of freefall through h and axiality are false. It just makes the problem tractable.

Even so, nobody has convincingly solved even the simplified problem!

[metamars]

[COLOR=black]You need to get Heiwa and Max Photo to be your helpers on this; Jones and his thermite can help, and Tony, he is an expert at research.

Don't you agree that the best help of all would be somebody like Ari-Gur or Singer?

[Heiwa]

Let's start again.

The structure below the initiation zone is much stronger at ground level than at at initiation level. We are interested what happens at the initiation level so the spring constant k or C at the initiation level must be considered. What can it be? 2 GN/m ?

The mass above m can not be considered as rigid or constant (as Bazant does) and must be divided into parts connected by springs. Thus m = m1 + m2 ... etc.

So what happens when mass m1 contacts (impacts?) the structure below with a modified spring constant at initiation level (a little before m2, m3, etc comes into action)?

m1 evidently compresses the structure below ... and bounces back, where it meets m2.

I can visualize that some parts of m1 and m2 then at this meeting in the air are squeezed out outside the foot print of the structure below ... and will not assist in the future action on the structure below. Energy is thus lost.

Then m3 comes into action and the same things happens.

I would expect that most of the kinetic energy from above (which is not very much by the way) is lost that way so there is no risk of overloading the structure below.

I have to repeat that the forensic evidence doesn't support my theory above. Forensic evidence shows that a bomb is dropped on the building.

Where could it have come from?

[Wildy]

I have to repeat that the forensic evidence doesn't support my theory above. Forensic evidence shows that a bomb is dropped on the building.

Where could it have come from?

Really, Forensic evidence shows that? I never knew. The last time I checked Forensic Science made sense...

Besides if it was a bomb, could it have been a napalm bomb?

[beachnut]

Don't you agree that the best help of all would be somebody like Ari-Gur or Singer?I wonder if he is so inclined to use real work, or their work. Unknown if he can handle real help. He has already signed up to support the dyed in the wool expert 9/11 truth movement.

[SDC]

I have to repeat that the forensic evidence doesn't support my theory above. Forensic evidence shows that a bomb is dropped on the building.

Where could it have come from?

I'm sorry, but could you provide that "forensic evidence"? I thought the usual complaint was that everything had been hauled away from the site too soon for it to be used as "forensic evidence," and that in itself was what certain people suspicious.

So the lack of evidence is the evidence?

[Heiwa]

Really, Forensic evidence shows that? I never knew. The last time I checked Forensic Science made sense...

Besides if it was a bomb, could it have been a napalm bomb?

Well, forensic evidence doesn't show what caused the collapse in the first place! To me it looks like a sudden explosion because the wall columns in the initiation zone seem to be the last structure to fail. I cannot see a bomb. I cannot see m1 falling down making contact (m1 = first floor above?) with the floor in the initiation zone, or m2 (second floor coming after?), etc. either.

This m = m1 + m2 + m3 ... is actually a Nist suggestion! 6 or 11 floors above suddenly dropped down one after another ... and global collapse ensued.

I wonder why so may floors suddenly dropped down. I live in a high rise building so I like to find out. I don't want the floor above to drop down on me.

[Heiwa]

I'm sorry, but could you provide that "forensic evidence"? I thought the usual complaint was that everything had been hauled away from the site too soon for it to be used as "forensic evidence," and that in itself was what certain people suspicious.

So the lack of evidence is the evidence?

Not at all. The forensic evidence is live videos. Just look.

[SDC]

Well, the definition I found (Businessdirectory.com with a quick search) says videos are not forensic evidence: "Evidence (http://www.businessdictionary.com/definition/evidence.html) usable in a court, specially the one obtained by scientific methods (http://www.businessdictionary.com/definition/scientific-method.html) such as ballistics, blood test (http://www.businessdictionary.com/definition/test.html), and DNA (http://www.businessdictionary.com/definition/distributed-network-architecture-DNA.html) test." Videos may be evidence, but they can't (?) be called forensic evidence. (Warning: I attended only the Dick Wolf School of Criminal Law.)

Freedictionary is more liberal, but I think when people nowadays think of "forensic evidence" they think of the scientific kind, not "it looked like it on that there video."
1. Relating to, used in, or appropriate for courts of law or for public discussion or argumentation.
2. Of, relating to, or used in debate or argument; rhetorical.
3. Relating to the use of science or technology in the investigation and establishment of facts or evidence in a court of law: a forensic laboratory.

[R.Mackey]

Well, forensic evidence doesn't show what caused the collapse in the first place! To me it looks like a sudden explosion because the wall columns in the initiation zone seem to be the last structure to fail. I cannot see a bomb. I cannot see m1 falling down making contact (m1 = first floor above?) with the floor in the initiation zone, or m2 (second floor coming after?), etc. either.

You cannot possibly be suggesting that the upper block did not contact the lower floors. The floors were over 60 meters across! How could it miss??

Answer it elsewhere, start a new thread if you must. You're off-topic, and derailing a potentially useful thread. Fair warning has been issued.

[DGM]

Not at all. The forensic evidence is live videos. Just look.
This is a very interesting thread debated by a few real engineers about real concerns. Would you please take your argument elsewhere.

[Apollo20]

Heiwa:

Two points:

Where do you get your spring constant value of 2 GN/m? You appear to pull this number out of a (truss) hat!

Secondly, you say there was no bowing/buckling of the exterior wall columns prior to the collapse of the towers. Well please take a look at Fig 6-21 on page 178 of NIST NCSTAR 1-6. That sure looks like bowing of the east face wall near floor 80 of WTC 2 to me.

[GregoryUrich]

You can't prove the WTC can not fail due to fire after the impact. You could live up to your membership in 9/11 truth and help with the petition of truth you signed.

Oops, you have made over 6, errors. Good luck next time. You do understand this is a model. Which paper? Oh, the one they did right after the WTC fell. Oh, then you can do it again and show how the concept is correct since the building did fall. If not you are wasting your time.

As seen you have not proved anything about 9/11, you are just attacking a model. It would be better to submit your own model. But I know you are trying to prove the WTC can not fail due to impact and fire alone. When will you prove the silent explosives and or the nut case thermite idea is real? Good work, you are attacking a model; If I was doing this I would just produce the work you really want, your so called paper to prove the WTC can not fail; like Ross. Ross was dead wrong.

So when will your final paper be done?

Which WTC does not fail? What about the other one? 3 days, 6 years, so?

You need to get Heiwa and Max Photo to be your helpers on this; Jones and his thermite can help, and Tony, he is an expert at research. With all that help you will be on your way. When you fix a few errors your paper will be a very good paper on a model about the WTC. Good luck again. (have you published this in the thermite inspired Journal of Truthyness yet?

I am sorry, but...

6 errors. Let's hear 'em. Put up or shut up!

[JamesB]

I wonder why so may floors suddenly dropped down. I live in a high rise building so I like to find out. I don't want the floor above to drop down on me.

Well if an airliner crashes into a floor above you and starts a massive fire, I suggest you leave immediately.

[GregoryUrich]

Doc, understanding is a strange thing - when you understand something, it seems infinitely easy, and when you don't, it seems infinitely difficult.

I am sure if someone oriented you, you'd probably be shrieking like 2nd grader at recess as you let in how simple - how simplified - how over-simplified - all this really is.


Doc, I'll tell you where I'm lost. I for the life of me can fathom why everyone is so interested in collapse progression.

The interesting question - and the important question from a 'whodunit" perspective - is what initiated collapse.

If collapse progression is an unquenchable fetish, then at a minimum recognize that output from WHAT INITIATED COLLAPSE? is input for HOW DID COLLAPSE PROGRESS?

If you think collapse initiation was not catalyzed, and it was, then the input for your collapse progression modeling will likely be incorrect.

Studying collapse progression before resolving collapse initiation is putting the cart before the horse.

Photon Max

,xaM

.tnatropmi erom yletinifed si noitaitini espalloC.

Nonetheless, the evidence of temperatures reached prior to collapse is neither representative nor conclusive. To make any progress on initiation, fire modeling is necessary. Unfortunately, I perceive fire modelling as beyond me, so I am focusing on the issues I might understand without months of reducating myself: fall times and collapse progression.

Collapse progression seems to be a close call, but it would disprove the gravity driven collapse hypothesis if collapse arrest could be convincingly demonstrated. I do see value in ruling out any one of the existing hypotheses, which would help us to focus on the others or to come up with new ones.

[metamars]

I wonder if he is so inclined to use real work, or their work. Unknown if he can handle real help. He has already signed up to support the dyed in the wool expert 9/11 truth movement.

As have I. I just sent an email to Professor Ari-Gur with an invitation to participate in this thread. I also asked him to extend the invitation to Professor Singer.

Have a nice day.

[cmcaulif]

If you follow their argument, you can't get to equation 3 without failure at the first impact. The additional mgh never comes into play!

I realize this, but I think it would be much simpler to modify equation three to include the energy displaced elastically, as well as accounting for the upper block. Equation one, due to its very approximate nature, is much less appropriate and in my opinion not a whole lot of info can really be taken away from it, other than that the building was made to perform in circumstances well outside what the designers could have anticipated.

[T.A.M.]

Not at all. The forensic evidence is live videos. Just look.

Did someone "Stundie" this, because they should...

TAM:)

[bje]

Not at all. The forensic evidence is live videos. Just look.

Except when videos are inconvenient for you, Heiwa. To wit, you wrote:

Conclusions (based on negative evidence):

A. The alleged hijacked planes did not crash at the various sites.
B. Whatever caused damage at the various crash sites was not a hijacked airplane.

http://www.911blogger.com/node/2406?page=1


Ooops! How are you going to get out of that fix, Heiwa?

[Major_Tom]

Dave writes:

all that actually means is that Bazant's model goes to great lengths to assume that the impulse delivered to the lower structure is done so in such a way as to maximise the lower structure's ability to resist that impulse, i.e. axially on the columns. In a more realistic scenario, the columns impact on the floors, which are quite incapable of bearing even the static loadings, and will therefore collapse progressively. Without the cross-bracing of the floors, the columns are too slender to stand independently. Therefore, column-on-floor impact is energetically greatly in favour of collapse propagation compared to column-on-column impact.




Dave, Let's take a typical core column: Column 1003. The elements of which are seen below.

http://www.sharpprintinginc.com/911_math/column1003.jpg



This was the actual column, consisting of 42 component column sections connected by welds.

The "top section" consists of the first 5 columns shown welded end to end.


Do you honestly think that if the top 5 sections were rammed into the lower 37 sections, also welded end to end, that this ridiculous "crush up-crush down" phenomenon will take place?


Now let's remember that these sections were seen for the most part perfectly straight and with clean breaks along their welds within the debris.


Which welds do you think will break first in a head-on collision?

The smaller I-beam connections in the top part or the box column welds in the bottom part?


Honestly?



And what meaning will using a spring equation ultimately have if your spring breaks into 30 pieces before plastic distortion occurs on the component parts?

[beachnut]

6 errors. Let's hear 'em. Put up or shut up!
Take a deep breath and figure it out. There are several good papers on the topics you need to review to complete your work. With some help from your peers at Scholars for 9/11 Truth & Justice (http://stj911.com/index.html (http://stj911.com/index.html) ) you could fix all your errors. Six are just reading your paper real quick. I am sorry, but I do not have access to the experts you have. http://stj911.com/members/index.html (http://stj911.com/members/index.html)

So I am sure Dr. Frank Legge and Tony Szamboti can help you with your errors! Wait, oops their papers suck.

What about Dr. Kevin Barrett and Dr. Steven Jones, now those guys must be able to fix a few errors and help you even better than I.

If that fails, you always have the smith brothers, they are all proud members of your esteem group. You can use John Smith, or Jimmy Smith, or the John Paul Smith. If they fail you, you can get the trauma nurse John Cox to help you. I have never worked with these guys, but if they see the light of truth and joined the prestigious Scholars for 9/11 Truth & Justice like you have; you are in like Flynn. By golly you even have Barrie Zwicker to put some icing on your pile of peer review perfection.

Your motto is http://stj911.com/index.html (http://stj911.com/index.html)

Care is being taken to present the strongest, most credible research available,

I am positive your peer review paper will be perfect for, http://www.journalof911studies.com/ (http://www.journalof911studies.com/) , Journal of 9/11 Studies; where it will receive the peer review it deserves. I know Journal of 9/11 Studies will do the best it can to help you make your paper as error free as all the papers at Journal of 9/11 Studies can be.

Rest assured, after reviwing your paper, and the papers at Journal of 9/11 Studies, it is clear it is up to the standard required at Journal of 9/11 Studies. Perfection for 9/11 truth. Where Care is being taken to present the strongest, most credible research available,

[Hyperviolet]

Did someone "Stundie" this, because they should...

TAM:)
I certainly hope so.
As far as i'm concerned, it's an utter triumph.

[Newtons Bit]

Horsey dung!

The E plastic is during the initial collapse. That portion of the potential energy must be removed before the first impact. Bazant hand-waved this away as inconsequential. Oops!

I not sure what to make of the other bogus accusations.

That appears to be the case, and as such I apologize for the implication to Gordon Ross.

I'm still greatly concerned by your 500MJ figure. You thought to challenge Bazant on the mass of the block above, and on the stiffness of the structure below, but not on the energy required to deform the columns, which Bazant based on the same assumptions as the mass and the stiffness. It seems... dishonest to say the least.

You can use the work I've done to easily calculate the plastic bending capacity of the columns with a total cross-sectional area that's greater than what your mass and pe papers state. If its' 114MJ for 30 degree (http://newtonsbit.blogspot.com/2007/07/gordon-ross-shows-collapse-progression.html) plastic hinges, it's 3 times as much for 90 degree, or 342MJ total (compared to your 500MJ figure). It seems very odd to me that you chose to challenge every one of Bazant's numbers in the basic equation EXCEPT the one that would hurt your conclusion. You could sharpen your pencil and try to determine exactly what it is if you're feeling spry. I state 342MJ, but that is with a cross-section of steel somewhat larger than what you're using.

I've also shown you a more accurate way to calculate the stiffness, C, which comes to be 8.72GN/m for the entire structure starting at the 97th floor and down.

You also seem to have a rather large error in what the cross-sectional area of steel is for the 97th floor. I easily compute it as 6.701m^2. The units of your Ultimate Strength column is Pa/(m^2). It should just be Pascals (N/(m^2)). This would relate to an "Ultimate Strength" of 2680MN.

But let's step back. You show a total weight of 314MN. And your "Ultimate Strength" is 2680MN. That means just prior to plane impact, the steel in the towers had a service Demand-to-Capacity ratio of 0.117. All I can say about that is, no, it is not correct. You have either greatly underestimated the strength and area of steel, or vastly underestimated the total load above (or both). This does not pass the common sense test.

The maximum compressive capacity of the columns is of course not based on the tensile capacity of steel, but the yield stress. These columns will buckle. Lower in the tower they may not, but on the 97th floor, they definitely will.

[GregoryUrich]

Take a deep breath and figure it out. There are several good papers on the topics you need to review to complete your work. With some help from your peers at Scholars for 9/11 Truth & Justice (http://stj911.com/index.html (http://stj911.com/index.html) ) you could fix all your errors. Six are just reading your paper real quick. I am sorry, but I do not have access to the experts you have. http://stj911.com/members/index.html (http://stj911.com/members/index.html)

So I am sure Dr. Frank Legge and Tony Szamboti can help you with your errors! Wait, oops their papers suck.

What about Dr. Kevin Barrett and Dr. Steven Jones, now those guys must be able to fix a few errors and help you even better than I.

If that fails, you always have the smith brothers, they are all proud members of your esteem group. You can use John Smith, or Jimmy Smith, or the John Paul Smith. If they fail you, you can get the trauma nurse John Cox to help you. I have never worked with these guys, but if they see the light of truth and joined the prestigious Scholars for 9/11 Truth & Justice like you have; you are in like Flynn. By golly you even have Barrie Zwicker to put some icing on your pile of peer review perfection.

Your motto is http://stj911.com/index.html (http://stj911.com/index.html)

I am positive your peer review paper will be perfect for, http://www.journalof911studies.com/ (http://www.journalof911studies.com/) , Journal of 9/11 Studies; where it will receive the peer review it deserves. I know Journal of 9/11 Studies will do the best it can to help you make your paper as error free as all the papers at Journal of 9/11 Studies can be.

Rest assured, after reviwing your paper, and the papers at Journal of 9/11 Studies, it is clear it is up to the standard required at Journal of 9/11 Studies. Perfection for 9/11 truth. Where

Just as I thought. An empty long winded harangue about other people. Stay on topic. Deal with the issues. Or don't you understand them?

[GregoryUrich]

That appears to be the case, and as such I apologize for the implication to Gordon Ross.

I'm still greatly concerned by your 500MJ figure. You thought to challenge Bazant on the mass of the block above, and on the stiffness of the structure below, but not on the energy required to deform the columns, which Bazant based on the same assumptions as the mass and the stiffness. It seems... dishonest to say the least.
The reason I'm discussing this here, as opposed to a truther forum, is to get honest, critical feedback that can help me avoid mistakes that favor either side of the argument. Notice I am not posting this as fact. It is a request for comment. It's really a shame that I get accused of "truther bias" for any mistakes in that direction.

You can use the work I've done to easily calculate the plastic bending capacity of the columns with a total cross-sectional area that's greater than what your mass and pe papers state. If its' 114MJ for 30 degree (http://newtonsbit.blogspot.com/2007/07/gordon-ross-shows-collapse-progression.html) plastic hinges, it's 3 times as much for 90 degree, or 342MJ total (compared to your 500MJ figure). It seems very odd to me that you chose to challenge every one of Bazant's numbers in the basic equation EXCEPT the one that would hurt your conclusion. You could sharpen your pencil and try to determine exactly what it is if you're feeling spry. I state 342MJ, but that is with a cross-section of steel somewhat larger than what you're using.
This is a vaild point. I'll calculate that myself.

I've also shown you a more accurate way to calculate the stiffness, C, which comes to be 8.72GN/m for the entire structure starting at the 97th floor and down.
This point, while valid, is fairly insignificant, but I will include it.

You also seem to have a rather large error in what the cross-sectional area of steel is for the 97th floor. I easily compute it as 6.701m^2. The units of your Ultimate Strength column is Pa/(m^2). It should just be Pascals (N/(m^2)). This would relate to an "Ultimate Strength" of 2680MN.
Correct regaring the units. I use 4.18m^2. Why am I not accused of being a NWO agent? Are you including spandrel steel? Only a dishonest "truther" would do that.

Anyway lets calculate the column cross-sectional area for floor 97:

core columns + perimeter columns = 48.67 x 10^6 kg + 71.40 x 10^6 kg

column steel mass = 120.07 x 10^6 kg

column volume = 120.07 x 10^6 kg / 7850 kg/m^3 = 15.30 m^3

area = 15.30 m^3 / 3.66 m = 4.18 m^2

But let's step back. You show a total weight of 314MN. And your "Ultimate Strength" is 2680MN. That means just prior to plane impact, the steel in the towers had a service Demand-to-Capacity ratio of 0.117. All I can say about that is, no, it is not correct. You have either greatly underestimated (over-?) the strength and area of steel, or vastly underestimated the total load above (or both). This does not pass the common sense test.
Using the area above and yield strength, the ("ultimate?") strength is 1050 GN m. So the D/C ratio is 0.308 which is not unreasonable and amounts to a safety factor (design load/actual capacity) between 1.5-3. Seems to add up.

The maximum compressive capacity of the columns is of course not based on the tensile capacity of steel, but the yield stress. These columns will buckle. Lower in the tower they may not, but on the 97th floor, they definitely will.
So buckling strength should be used. OK.

[uk_dave]

GU,

How finely balanced do you think this issue is, with regards to the possibility that the collapse could have progressed or could not have progressed?

Is it an order of magnitude whereby you could say categorically that there is no way on earth those towers could have collapsed without some additional assistance, or is it more of a 50/50 chance that the collapse could have progressed?

The reason I ask is that unless you or someone else can categorically state that the collapse could not have occurred, and that the margin of error for such a claim is too small for there to be any doubt, then you really are not going to be able to provide convincing evidence that something else was responsible for what was seen on that day. If there is the slightest possibility that structural damage and fires caused the towers to collapse then that is what happened because that is what we witnessed.

While this debate is fascinating in terms of the technical expertise of the participants I am inclined to (facetiously) request that when this thread dies, someone here might be prepared to calculate for me the amount of force I need to apply to the lightswitch which controls my kitchen lights, because, while I am perfectly capable of successfully switching them on and off without any problems, I am troubled each time by not knowing just how much effort I need to put into this act. Do you get what I'm saying here? :)

[beachnut]

Just as I thought. An empty long winded harangue about other people. Stay on topic. Deal with the issues. Or don't you understand them?
Give me a break, I looked up some of your peers who could help you find the errors. As seen already people at this forum have helped you the petition signing 9/11 truth group member! They have found errors, I found errors; they shared some ideas with you. I gave you the old fight story and told you to get your peers to help you.

I gave you a list and warned you about a few! What else do you want? I give advice as an engineer would to a card carrying truth member. You are saving me by finding the truth.

Go join your 0.00087 percent of all engineers in 9/11 truth. Your new paper is moving your closer to your peers, all 0.00087 percent of all world engineers. Some people will help you find your errors, like the Smith bothers. There sure are a lot of smiths in your group; I wonder if they are… anyway.

I am amazed at how your engineering is slowly becoming more like your peers. Soon you will be in full 9/11 truth panic mode. At least UBL understands impact and fire. You guy in 9/11 truth do not. And at least Robertson does too. Gee, he built the towers and already knows your future paper of no collapse is wrong. I wonder what you missed.

No please, go get help from your peers at the Journal and your 9/11 group of truth. Good luck; it has been 6 years and now your group of truth is entering it's 7th year of false information. Do not tell me I wasted my time recommending your peers to help you.

BTW, when will you know the actual strength of one floor. Not the building section, but a floor? Your stuff is funny as you calculate what? You must come up with how many pounds/force/mass one floor can take at impact. Even just sitting, now many floors/weight can sit on one floor? Your junk is cool, you wasted a lot of time, but you have not stated the mass one floor can hold. What would that be in pounds? One floor; at the impact area. 71,000,000 pounds? 39,000,000 pounds? I think you are trying to model the building cross section and have ignored the problem is just one floor. ?

[Dave Rogers]

Dave, Let's take a typical core column: Column 1003. The elements of which are seen below.

This was the actual column, consisting of 42 component column sections connected by welds. The "top section" consists of the first 5 columns shown welded end to end. Do you honestly think that if the top 5 sections were rammed into the lower 37 sections, also welded end to end, that this ridiculous "crush up-crush down" phenomenon will take place?

Now let's remember that these sections were seen for the most part perfectly straight and with clean breaks along their welds within the debris. Which welds do you think will break first in a head-on collision? The smaller I-beam connections in the top part or the box column welds in the bottom part? Honestly?

And what meaning will using a spring equation ultimately have if your spring breaks into 30 pieces before plastic distortion occurs on the component parts?

I'm not sure who you think you're replying to here, but it doesn't seem to be me. I said that the Bazant model was an oversimplification that's strongly biased against collapse propagation compared to reality, and you seem to agree with me while claiming you're disagreeing. Your last paragraph is more or less a paraphrase of my second, which you didn't post. Everything you say seems to imply that collapse was more energetically favourable in reality than in the Bazant model. So what exactly is your point?

Dave

[Heiwa]

Except when videos are inconvenient for you, Heiwa. To wit, you wrote:




Ooops! How are you going to get out of that fix, Heiwa?

No problems at all. This thread is about GregoryUrich c/ Bazant and you are OT, but I reply anyway. I note with pleasure the absence of many garbish comments in this thread.

The videos of WTC1, real time forensic evidence, evidently do not show a Bazant gravity collapse that, if it would have taken place for the second time in world history (WTC2 was the first), should have taken much longer and looked completely different . Here we all, normal people with average IQ, see that no heated columns buckle, crumble or hinge in the 4000 m² large initiation zone so that potential energy in the tower above can be released.

Potential energy release is the official (only) proximate (nearest before) cause of collapse in combination with lack of strain energy in the remainder structure.

But anybody with good eyes can see that the perimeter columns in the initiation zone are intact so that no potential energy is released above, so, logically, strain energy below is of no importance, etc.

It seems on the other hand that the whole tower above the initation zone with intact perimeter columns explodes prior to released potential energy contacts the initiation zone followed by alleged collapse below as if it was hit by a bomb. This everybody can see.

Nist seems to have backed down about the 'release of potential energy' and now (FAQ Decemebr 2007) suggests that 6 -11 floors above dropped down into the initiation zone (no heated, crumbling, hinging or buckling columns) and overloaded a floor there, so that this floors then dropped down and caused ... global collapse!! I cannot see any evidence for that on any video.

I have therefore (http://heiwaco.tripod.com/nist.htm ) kindly recommended Nist to review the conclusion about 'release of potential energy' as cause of global collapse (still awaiting a reply) and clarify the dropping floors theory.

Kind regards

Heiwa

PS - thanks for reminding me that I have in another thread doubted that WTC1 would have been hit by a plane 80+ minutes before alleged release of potential energy with remaining, intact perimeter columns. We can discuss that in that thread.

[Dave Rogers]

Here we all, normal people with average IQ, see that no heated columns buckle, crumble or hinge in the 4000 m² large initiation zone so that potential energy in the tower above can be released.

No, Heiwa. We normal people see the photographs in which the perimeter columns are bending inwards, and in the Trinity Church video we can very clearly see them buckle, crumple and hinge as the collapse initiates. It's only those who refuse to see this that have a problem.

Dave

[Newtons Bit]

Correct regaring the units. I use 4.18m^2. Why am I not accused of being a NWO agent? Are you including spandrel steel? Only a dishonest "truther" would do that.

I just pulled the number straight from your spreadsheet without seeing that it included spandrel steel. This changes the stiffness to 8.27. Regarding the stiffness, are you sure you want to use the entire tower? You could compute the speed of the elastic wave in the steel based on the time it would take to strain the steel to 0.2%. This will drastically increase the stiffness of the spring.

Regardless, using your mass, the correct cross-sectional area, Eplastic of 342MJ and a stiffness of 8.27GN/m, I get an overload ratio of about 2. Then again, I'm not so hot at arithmetic :D

Your Eplastic figure is very important in this calculation and reasonably should be dropped. To assume the columns undergo 90 degree plastic hinges is a little absurd. Especially considering 1/3 of the columns on that floor will have a splice point at a plastic hinge. That splice will not rotate, it will fracture immediately absorbing almost no energy.

[funk de fino]

No problems at all. This thread is about GregoryUrich c/ Bazant and you are OT, but I reply anyway. I note with pleasure the absence of many garbish comments in this thread.

The videos of WTC1, real time forensic evidence, evidently do not show a Bazant gravity collapse that, if it would have taken place for the second time in world history (WTC2 was the first), should have taken much longer and looked completely different . Here we all, normal people with average IQ, see that no heated columns buckle, crumble or hinge in the 4000 m² large initiation zone so that potential energy in the tower above can be released.

Potential energy release is the official (only) proximate (nearest before) cause of collapse in combination with lack of strain energy in the remainder structure.

But anybody with good eyes can see that the perimeter columns in the initiation zone are intact so that no potential energy is released above, so, logically, strain energy below is of no importance, etc.

It seems on the other hand that the whole tower above the initation zone with intact perimeter columns explodes prior to released potential energy contacts the initiation zone followed by alleged collapse below as if it was hit by a bomb. This everybody can see.

Nist seems to have backed down about the 'release of potential energy' and now (FAQ Decemebr 2007) suggests that 6 -11 floors above dropped down into the initiation zone (no heated, crumbling, hinging or buckling columns) and overloaded a floor there, so that this floors then dropped down and caused ... global collapse!! I cannot see any evidence for that on any video.

I have therefore (http://heiwaco.tripod.com/nist.htm ) kindly recommended Nist to review the conclusion about 'release of potential energy' as cause of global collapse (still awaiting a reply) and clarify the dropping floors theory.

Kind regards

Heiwa

PS - thanks for reminding me that I have in another thread doubted that WTC1 would have been hit by a plane 80+ minutes before alleged release of potential energy with remaining, intact perimeter columns. We can discuss that in that thread.

1. definition of garbish again heiwa?
2. if you are normal with average IQ it says little for average IQ and how obviously above average most of the peple i know are
3. Your eyes need tested
4. i cannot see it

if you watch the videos and look at all available photographs and are seriously claiming you cannot see the columns buckling inwards then i say you are a liar

you are spoiling this thread, which has good potential, with your buffoonery

[Major_Tom]

Dave asks:

I'm not sure who you think you're replying to here, but it doesn't seem to be me. I said that the Bazant model was an oversimplification that's strongly biased against collapse propagation compared to reality, and you seem to agree with me while claiming you're disagreeing. Your last paragraph is more or less a paraphrase of my second, which you didn't post. Everything you say seems to imply that collapse was more energetically favourable in reality than in the Bazant model. So what exactly is your point?




Dave, I have many arguments against the original assumtions in the Bazant model.

I'll present each argument as explicitly as I can.



Argument #1:


Let's consider the head-on collision after a 12 foot fall of a typical core column, Column 1003, shown below.

http://www.sharpprintinginc.com/911_math/column1003.jpg


In the case of the North Tower, Bazant's "upper block" portion of the column will only be the first 5 I-beam sections shown in the diagram above connected end to end.

The largest and strongest 37 column sections shown, connected end to end, constitute the ""lower block".



Now we ram the two parts together.



We know that the large, large majority of core box columns failed at weld connections before suffering any permanent distortion.



Just based on the principle that bigger tends to be stronger, where would you think the first weld breakage would occur just after impact?


Wouldn't the welds in the "upper block" tend to fail first?


Bazant requires that the upper block be comically rigid.

If you remove the assumption of rigid, Bazant has no model.






Argument #2: During the "collapse" of the North Tower, a "spire" was seen to stand well after the rest of the building had collapsed.

http://www.sharpprintinginc.com/911_old/Photo%20archives/spire/view%204.jpg


This spire was photographed from at least 5 different angles, and so it is not too difficult to identify which core columns these are.

I and a few friends have identified these columns as 701 through 706 and 801 through 806, proof shown below.

http://www.sharpprintinginc.com/911/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=11&MMN_position=23:23



Let's take a look at the diagram below to see where column rows 700 and 800 were situated.

http://www.sharpprintinginc.com/911_old/Photo%20archives/pictures%20with%20graphics-zoom/wtc%20core%20labels.jpg



Notice that they are the 2 innermost column rows.

Most of the columns in these 2 rows were seen standing, unsupported, more than 50 stories high for a good 15 seconds after the rest of the building had completely collapsed.


Also note that in the diagram above the relative sizes of column cross-sections are fairly accurate. It is a sub-level 2 cross-sectional view. Note how the 700 and 800 columns are among the WEAKEST in the core. Note how columns in rows 500 and 1000 are the STRONGEST in the core.


The question is: How can anyone model the collapse of the core on progressive weld failures occuring naturally (without "help") which leave the columns in the center 2 rows of the core standing unsupported for more than 50 stories?

[Dave Rogers]

Major Tom,

Firstly, your entire approach here is bizarre. You're trying to dispute my assertion that the Bazant model is oversimplified by claiming that the Bazant model is oversimplified. This is what's known as "being in violent agreement".

Secondly, your AutoCAD analysis of the spires isn't as conclusive as you claim, in that the lineup of columns for rows 500-600 is clearly as good a fit to the photographs as the lineup for rows 700-800; in fact, going by the most clearly visible columns it's actually a better fit. That would then mean that the tallest surviving column is one of the four corner columns from the core, hardly a counter-intuitive result.

Dave

[GregoryUrich]

Give me a break, I looked up some of your peers who could help you find the errors. As seen already people at this forum have helped you the petition signing 9/11 truth group member! They have found errors, I found errors; they shared some ideas with you. I gave you the old fight story and told you to get your peers to help you.

I gave you a list and warned you about a few! What else do you want? I give advice as an engineer would to a card carrying truth member. You are saving me by finding the truth.

Go join your 0.00087 percent of all engineers in 9/11 truth. Your new paper is moving your closer to your peers, all 0.00087 percent of all world engineers. Some people will help you find your errors, like the Smith bothers. There sure are a lot of smiths in your group; I wonder if they are… anyway.

I am amazed at how your engineering is slowly becoming more like your peers. Soon you will be in full 9/11 truth panic mode. At least UBL understands impact and fire. You guy in 9/11 truth do not. And at least Robertson does too. Gee, he built the towers and already knows your future paper of no collapse is wrong. I wonder what you missed.

No please, go get help from your peers at the Journal and your 9/11 group of truth. Good luck; it has been 6 years and now your group of truth is entering it's 7th year of false information. Do not tell me I wasted my time recommending your peers to help you.

BTW, when will you know the actual strength of one floor. Not the building section, but a floor? Your stuff is funny as you calculate what? You must come up with how many pounds/force/mass one floor can take at impact. Even just sitting, now many floors/weight can sit on one floor? Your junk is cool, you wasted a lot of time, but you have not stated the mass one floor can hold. What would that be in pounds? One floor; at the impact area. 71,000,000 pounds? 39,000,000 pounds? I think you are trying to model the building cross section and have ignored the problem is just one floor. ?

Where's the list?

[GregoryUrich]

No, Heiwa. We normal people see the photographs in which the perimeter columns are bending inwards, and in the Trinity Church video we can very clearly see them buckle, crumple and hinge as the collapse initiates. It's only those who refuse to see this that have a problem.

Dave

Dave, do you have a link to the Trinity Church video?

[Dave Rogers]

Dave, do you have a link to the Trinity Church video?

http://video.google.com/videoplay?docid=-5405555553528290546

Dave

[GregoryUrich]

I just pulled the number straight from your spreadsheet without seeing that it included spandrel steel. This changes the stiffness to 8.27. Regarding the stiffness, are you sure you want to use the entire tower? You could compute the speed of the elastic wave in the steel based on the time it would take to strain the steel to 0.2%. This will drastically increase the stiffness of the spring.

Regardless, using your mass, the correct cross-sectional area, Eplastic of 342MJ and a stiffness of 8.27GN/m, I get an overload ratio of about 2. Then again, I'm not so hot at arithmetic :D

Your Eplastic figure is very important in this calculation and reasonably should be dropped. To assume the columns undergo 90 degree plastic hinges is a little absurd. Especially considering 1/3 of the columns on that floor will have a splice point at a plastic hinge. That splice will not rotate, it will fracture immediately absorbing almost no energy.

The splice is between floor 98 and 99, where the columns become approximately 15-20% thinner. So are we assuming the upper floor will fail first?

[Heiwa]

No, Heiwa. We normal people see the photographs in which the perimeter columns are bending inwards, and in the Trinity Church video we can very clearly see them buckle, crumple and hinge as the collapse initiates. It's only those who refuse to see this that have a problem.

Dave

Before collapse of the building can start, there must be release of potential energy from above that allegedly starts when all columns in the initiation zone fail simultaneously.

The roof cannot move before all the columns in the initiation zone fail, etc. If the roof moves before, something is wrong. I see the roof moving before all the columns at the initiation zone has failed completely.

Run various videos from different view angles synchronously side by side and watch - frame by frame.

After all the columns in the initiation zone has failed (i.e. are not carrying any load) release of potential energy should start. No collapse of the tower below has started.

This potential energy is, in theory, flying in the air, and should take a certain time to reach the top floor of the initiation zone.

Various 'experts' suggest that the potential energy corresponds to the mass above moving down 3.7 meters = the height of the columns between two floors (the top floor of the tower below and the bottom floor of the tower above) that is mostly full of air. OK - this should take only 0.5 seconds.

Fair enough. The amount of potential energy released is then 340 kWh that corresponds to 40 kgs of diesel oil.

Then a vertical 'impact' is supposed to take place. The lowest floor of the mass above lands on the top floor of the tower below. The speed cannot be more than 10 kms/h. Probably less. If anything is seen moving vertically faster, something is wrong.

All the columns and other stuff in between the two floors are supposed to be just crushed.

And it is now, for unexplained reasons, that global collapse of tower below just ensues, according Nist. No parts can be thrown out sideways before this event takes place = the two floors bumping together. If anything is seen thrown outwards before, something is wrong.

However, the amazing release of potential energy seems to take at least 5 seconds as seen on all videos. But it should take only 0.5 seconds. And during these 5 seconds the complete top part seems to crumple, or actually, disintegrate.

This I see on all the videos and I find that it does not tally with what Nist and Bazant are saying. I have no problem with that.

[einsteen]

Dave, did you notice those rows of squibs, the distance between them is not exactly the distance of a story, but much more, I've noticed that also for a couple of other movies that I synchronized in time. This is a big contradiction for the theory that these are caused by falling floors. The same appears at the other side of the building in spite of the fact that the block topples, the floors cannot enclose the amount of air. The first row is above the mechanical floors, the 2nd is in the mechanical floors and the third below. There are a couple of other things also that doesn't fit the official story.

[Dave Rogers]

Dave, did you notice those rows of squibs, the distance between them is not exactly the distance of a story, but much more, I've noticed that also for a couple of other movies that I synchronized in time. This is a big contradiction for the theory that these are caused by falling floors. The same appears at the other side of the building in spite of the fact that the block topples, the floors cannot enclose the amount of air. The first row is above the mechanical floors, the 2nd is in the mechanical floors and the third below. There are a couple of other things also that doesn't fit the official story.

I didn't see any squibs, no. I saw an enormous amount of what looked like fine particulate ejecta, but no flashes from explosive devices. It may well be that the floors didn't collapse quite as neatly and sequentially as the drastically over-simplified collapse theories suggest; for one thing, multiple floor collapses could have resulted from column fracture at the weld planes and bolt connections, for which there's a good deal of evidence. Frankly, though, it'll take rather more than some alleged inconsistencies in the levels at which dust was ejected to make me seriously consider the possibility that the towers were brought down by explosives that were installed without anyone noticing, didn't emit any flash, miraculously pulled the perimeter columns inwards at the point of detonation and only threw out dust relatively slowly. Really, this looks nothing like an explosive demolition, and it's only the truly delusional who can claim sincerely that it does.

Dave

[Newtons Bit]

The splice is between floor 98 and 99, where the columns become approximately 15-20% thinner. So are we assuming the upper floor will fail first?

I'm not talking about the differences between the upper or lower floor, just the general layout of columns and the total energy required to completly fail one floor of columns.

The columns are spliced every 3 floors, but they're staggered. This means that 1/3rd of the columns are spliced at every floor. These splices can't develop the full bending capacity of the steel column and will thus fail at the splices first.

[einsteen]

I didn't see any squibs, no. I saw an enormous amount of what looked like fine particulate ejecta, but no flashes from explosive devices. It may well be that the floors didn't collapse quite as neatly and sequentially as the drastically over-simplified collapse theories suggest; for one thing, multiple floor collapses could have resulted from column fracture at the weld planes and bolt connections, for which there's a good deal of evidence. Frankly, though, it'll take rather more than some alleged inconsistencies in the levels at which dust was ejected to make me seriously consider the possibility that the towers were brought down by explosives that were installed without anyone noticing, didn't emit any flash, miraculously pulled the perimeter columns inwards at the point of detonation and only threw out dust relatively slowly. Really, this looks nothing like an explosive demolition, and it's only the truly delusional who can claim sincerely that it does.

Dave

Maybe I shouldn't call it squibs, but if it is pulveriation of concrete (there is barely movement, in the beginning) then it should also be something that occurs on the level of a story. Ok I understand this is a non-lineair extremely chaotic process, everything will crush randomly, but on the other hand the rows are very lineair and as far as I can see at all sides of the building. I will soon try to synchronize 4 videos in a mosaic to see if this is the case.

[GregoryUrich]

I'm not talking about the differences between the upper or lower floor, just the general layout of columns and the total energy required to completly fail one floor of columns.

The columns are spliced every 3 floors, but they're staggered. This means that 1/3rd of the columns are spliced at every floor. These splices can't develop the full bending capacity of the steel column and will thus fail at the splices first.

I know the external columns are staggered, but I've never heard anything about the core being staggered. In fact, I've been through the SAP model core data and none are staggered.

[bje]

PS - thanks for reminding me that I have in another thread doubted that WTC1 would have been hit by a plane 80+ minutes before alleged release of potential energy.

Except when videos are inconvenient for you, Heiwa. To wit, you wrote:

Conclusions (based on negative evidence):

A. The alleged hijacked planes did not crash at the various sites.
B. Whatever caused damage at the various crash sites was not a hijacked airplane.

http://www.911blogger.com/node/2406?page=1
Ooops! How are you going to get out of that fix, Heiwa? Videos and photos of UA 175 hitting WTC 2 are irrefutable, to wit:

TP1nkucAlHg

[DGM]

Maybe I shouldn't call it squibs, but if it is pulveriation of concrete (there is barely movement, in the beginning) then it should also be something that occurs on the level of a story. Ok I understand this is a non-lineair extremely chaotic process, everything will crush randomly, but on the other hand the rows are very lineair and as far as I can see at all sides of the building. I will soon try to synchronize 4 videos in a mosaic to see if this is the case.
Why do you say concrete? Wouldn't ceiling tiles and drywalled partitions be the first to go?

[einsteen]

Yes DGM, whatever you want

[Newtons Bit]

I know the external columns are staggered, but I've never heard anything about the core being staggered. In fact, I've been through the SAP model core data and none are staggered.

Yes, I'm referring to the external columns here. There'd be no reason to stagger the core columns. There's another mechanic that will "assist" the core columns in failing without developing the full plastic bending capacity, but it's a bit more complicated. I need to do some maths with them before I can really put my finger on it though.

[rwguinn]

Yes, I'm referring to the external columns here. There'd be no reason to stagger the core columns. There's another mechanic that will "assist" the core columns in failing without developing the full plastic bending capacity, but it's a bit more complicated. I need to do some maths with them before I can really put my finger on it though.

s'ok, NB
Just remember that no failure ever occurs before ultimate, and Young's Modulus is constant at 29.9e6 psi for all values up to ultimate.

[Heiwa]

Maybe I shouldn't call it squibs, but if it is pulveriation of concrete (there is barely movement, in the beginning) then it should also be something that occurs on the level of a story. Ok I understand this is a non-lineair extremely chaotic process, everything will crush randomly, but on the other hand the rows are very lineair and as far as I can see at all sides of the building. I will soon try to synchronize 4 videos in a mosaic to see if this is the case.

It is not non-linear or extremely chaotic or flashes or floors or squibs or whatever you see or can dream of to disturb the thread in a terrorist like manner. It is very simple. OK, subtraction.

1. Use as starting time, Tstart, when all the columns have failed in the initiation zone, i.e. when the upper part is hanging in the air without any support. Easy to see on any video! Anyone can see that. This is when the release of potential energy starts = the cause of the whole mess. If you cannot see that, ask Nist and Bazant and they will tell you the time and how to establish it because they state it occurred and should know when. But you are smarter than that, so just look on your mosaic and establish Tstart. You need a watch or clock for that, BTW.

2. If anything happens before that = Tstart, e.g. the roof moves, the top part tilts och behaves strangely, top part starts falling apart, squibs, flashes, etc you have probably got it wrong and must start again, because nothing can happen before all columns in the initiation zone has failed ... simultaneously = Tstart. Sorry for saying that when you are so smart, but other readers of this message may need to be reminded.

3. Establish then the time, Timpact, when the impact, or bump, between the upper, lose part and the fixed bottom part occurs. Again, if you have any difficulties, ask Nist, Bazant, FEMA, FBI, CIA, etc. for assistance. Freedom of information you know. But look out. HR 1955 is law (to be?) so don't use any force to find out because then you are by definition a terrorist. But if the event happened, there must be a time for it = Timpact.

4. Now it gets difficult - subtraction. What is (Tstart - Timpact) ?

If you cannot answer this simple question, I suggest you get ashamed of yourself and retire from JREF Forum for ... ever (would be best). We will then sadly miss your intelligent contributions, but that's life.

Look forward to a clear and concise response.

[WildCat]

:words:
Is it still your contention that no planes hit the WTC Heiwa?

[einsteen]

Heiwa,

I was responding to Dave and don't really understand your reply, but I hope that you, with your superior IQ, understand that I absolutely am no supporter of the gravity driven theory.

[beachnut]

Greg, your answer was where is the list?
(idiot CD ideas are coming up; that proves all your work is crap! have your CD chorus of woo stop doing the squib crap, it shows their complete ignorance on 9/11)

The question is how much weight can one floor take? 70,000,000 pounds? 31,000,000 pounds? What will the floor fail to hold?

[A W Smith]

Before collapse of the building can start, there must be release of potential energy from above that allegedly starts when all columns in the initiation zone fail simultaneously.

The roof cannot move before all the columns in the initiation zone fail, etc. If the roof moves before, something is wrong. I see the roof moving before all the columns at the initiation zone has failed completely.

Run various videos from different view angles synchronously side by side and watch - frame by frame.

After all the columns in the initiation zone has failed (i.e. are not carrying any load) release of potential energy should start. No collapse of the tower below has started.


Cz6VxxVdXuA

[einsteen]

avf2gDWQlck

[GregoryUrich]

avf2gDWQlck

Is the black line floor 97? Interesting that only part of the facade starts to collapse!

[GregoryUrich]

Greg, your answer was where is the list?
(idiot CD ideas are coming up; that proves all your work is crap! have your CD chorus of woo stop doing the squib crap, it shows their complete ignorance on 9/11)

The question is how much weight can one floor take? 70,000,000 pounds? 31,000,000 pounds? What will the floor fail to hold?

Clearly you don't have list. Only long "woo" infected harangues. You are back on ingore.

[Heiwa]

Heiwa,

I was responding to Dave and don't really understand your reply, but I hope that you, with your superior IQ, understand that I absolutely am no supporter of the gravity driven theory.

Pls discuss with Dave your OT stuff on a thread made for that. In my opinion you behave like terrorists on this forum.

[Heiwa]

Is it still your contention that no planes hit the WTC Heiwa?

??? Topic is GUrich c/ Bazant if release of potential energy caused the WTC1 collapse. Pls do not terrorize this thread with OT questions.

[cmcaulif]

Is the black line floor 97? Interesting that only part of the facade starts to collapse!

doesn't this just confirm what we already know, that the load was not evenly spread over one story?

[uk_dave]

Pls discuss with Dave your OT stuff on a thread made for that. In my opinion you behave like terrorists on this forum.

ooooo hissy fit.
From the man who doesn't know the difference between the wtc towers and conventional multistorey steel framed structures, has no idea regarding the known vulnerability of structural steel to fire and isn't even very coherent on the difference between thermal insulation and fireproofing.

[WildCat]

??? Topic is GUrich c/ Bazant if release of potential energy caused the WTC1 collapse. Pls do not terrorize this thread with OT questions.
It is on-topic! If you're not willing to concede that planes hit the WTC then there are likely many other things you are ignoring in your "calculations".

[Major_Tom]

Gregory notes:

I know the external columns are staggered, but I've never heard anything about the core being staggered.

None of the 47 core columns are staggered.

They all have column-to-column connections at same elevations.

This is why I introduced the idea of "weld planes".

There are about 40 separate horizontal planes separated by about 38 feet all the way up the building that contained every core column-to-column connection.

This is a unique and very important design within the towers.

[Newtons Bit]

This is a unique and very important design within the towers.

It's not unique, almost all buildings with columns over 50 feet splice the columns.

[beachnut]

Clearly you don't have list. Only long "woo" infected harangues. You are back on ingore.
The question is how much weight can one floor take? 70,000,000 pounds? 31,000,000 pounds? What will the floor fail to hold?

Oh, you do not know? Ignore? Easy question, how much weight can a WTC floor handle before it fails?

[Major_Tom]

Greg asks:

Is the black line floor 97? Interesting that only part of the facade starts to collapse!


Yes, the black line is floor 97 and is right along the tops of the windows.


The straight blackened horizontal lines across the entire north and west faces of floors 97 and 94, WTC 1 are truly fascinating.

Using the NIST NCSTAR 1.5A, Chapters 8 and 9 study of the fire progression of WTC 1 and 2, I extracted all the time-stamped photos and grouped them according which face is shown in the photo.

This way, only by looking at the pictures in order, anyone can see the progression of the fire activity from airplane impact to collapse on any of the 4 facades of WTC 1 or WTC 2.

At the following link I show the fire progression on the north and west faces, WTC 1.

http://www.sharpprintinginc.com/911/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=52&MMN_position=97:97


These photos show how these 2 horizontal blackened straight lines on floors 94 and 97 across the entire north and west faces slowly formed.


Gregory, this blackened line is rather interesting.

[GregoryUrich]

Greg asks:

Yes, the black line is floor 97 and is right along the tops of the windows.

The straight blackened horizontal lines across the entire north and west faces of floors 97 and 94, WTC 1 are truly fascinating.

Using the NIST NCSTAR 1.5A, Chapters 8 and 9 study of the fire progression of WTC 1 and 2, I extracted all the time-stamped photos and grouped them according which face is shown in the photo.

This way, only by looking at the pictures in order, anyone can see the progression of the fire activity from airplane impact to collapse on any of the 4 facades of WTC 1 or WTC 2.

At the following link I show the fire progression on the north and west faces, WTC 1.

http://www.sharpprintinginc.com/911/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=52&MMN_position=97:97

These photos show how these 2 horizontal blackened straight lines on floors 94 and 97 across the entire north and west faces slowly formed.

Gregory, this blackened line is rather interesting.

Great job with the photos. Very helpful to understand what took place. I was surprised there was so much fire apparent on floor 97 on the West Side when the majority of fuel went into 95-96.

[Major_Tom]

It's not unique, almost all buildings with columns over 50 feet splice the columns.

NB, I'm talking about the lack of staggered collections in the core. All 47 core columns have their column-to-column connections at the exact same elevations.

Correction: I don't know how unique the design is, but it is very important to understand to notice unique features of the "collapses" (demolitions).

This existence of unique "weld planes" separated by 3 floors is very important to know when modelling the towers, no?

Especially considering how column "failure" happened at these very welds.


For example, Einstein asks:

Dave, did you notice those rows of squibs, the distance between them is not exactly the distance of a story, but much more, I've noticed that also for a couple of other movies that I synchronized in time. This is a big contradiction for the theory that these are caused by falling floors. The same appears at the other side of the building in spite of the fact that the block topples, the floors cannot enclose the amount of air. The first row is above the mechanical floors, the 2nd is in the mechanical floors and the third below. There are a couple of other things also that doesn't fit the official story.

Maybe there is a relation?

[Major_Tom]

Greg, I'd like you to be familiar with this research tool. I remember you have mentioned "raging fires" before.

Having this ability to view each facade separately using NIST's own time stamped photos in the proper time sequence allows you to really see if these fires were "raging" or not, and for how long they "raged".


You can know the fire activity along any face at any time.

[Newtons Bit]

NB, I'm talking about the lack of staggered collections in the core. All 47 core columns have their column-to-column connections at the exact same elevations.

Correction: I don't know how unique the design is, but it is very important to understand to notice unique features of the "collapses" (demolitions).

Columns spliced at the same floor is a common characteric of buildings. Staggering the splices is uncommon. Though the net effect of staggering the moment frame splices would result in smaller splices. Oops.

[beachnut]

Pls discuss with Dave your OT stuff on a thread made for that. In my opinion you behave like terrorists on this forum.
You are not qualified to comment then on this thread, you paper is pure junk and really bad. Even 9/11 truth people have shown you errors and you persist to make bad decisions on 9/11 based on bad assumptions and bad engineering.

Do not forget you paper is really bad as you go around thinking you have something more that false information on 9/11!

You do not even know some simple stuff like:How much weight can one floor take? 70,000,000 pounds? 31,000,000 pounds? What will the floor fail to hold?

[bje]

??? Topic is GUrich c/ Bazant if release of potential energy caused the WTC1 collapse. Pls do not terrorize this thread with OT questions.

Oh, but it has everything to do with your claims, Heiwa:

Heiwa wrote:

"The Towers also survived the initial impacts of planes on 911 due to their redundancy."
...
From NIST report - NISTNCSTAR1-6D chapter 5.2 - we learn:
"The aircraft impacted the north wall of WTC 1 at 8:46 a.m. … between Floor 93 and Floor 98.
...
From chapter 5.3 we learn:
"The aircraft … impacted the south wall of WTC 2 at 9.03 a.m. … between Floor 78 and Floor 84.
...
"There was therefore plenty redundancy. A plane may crash into the bird cage and nothing happens."
...
Anders Björkman, M.Sc. Heiwa Co, Beausoleil, France - January 5, 2008. http://heiwaco.tripod.com/nist.htmThus we have you - Heiwa - admitting that aircraft hit each tower. And you claim that the impacts would have no effect on the tower whatsoever, even from the damage and fires they caused.

In 2006, Heiwa went to great lengths to claim NO aircraft hit WTC 1 and WTC 2.

There is clear (negative) evidence that no hijacked airplanes were involved in 911:
...
Conclusions (based on negative evidence):

A. The alleged hijacked planes did not crash at the various sites.
B. Whatever caused damage at the various crash sites was not a hijacked airplane.
...

"9/11/01 I was at Freiberg, Saxony, Germany. My daughter called and
asked me to watch TV news. But we had no TV in our old house built 1590
ca. Only later I had the opportunity to watch the 911 crash sites on video.

"And it was quite evident to me that due to lack of any airplane wreckage
anywhere that no airplanes ever caused the incidents. Furthermore - the
structural damages at WTC and Pentagon and the hole in the ground at
Pennsylvania cannot have been caused by airplanes for more reasons than
that there are no airplane wreckage parts anywhere."

http://www.911blogger.com/node/2406?page=1So we have Heiwa first claiming NO planes hit the towers. Then he reverses himself and says planes hit the towers but would have no effect. Interestingly, when asked to clarify his position, Heiwa has gone to great lengths to avoid answering.

Heiwa, if you claim aircraft would have NO effect on the Towers, why are you afraid to tell us whether planes hit or not? Something about your consistent evasions must be scaring you, am I correct, Heiwa?

Why are you afraid to clear up your contradiction, Heiwa?

[Norseman]

Is the black line floor 97? Interesting that only part of the facade starts to collapse!

No it does not. It moves simultaneously with the roof and the exterior wall above. The clip einsteen posted is just a bad quality crop. You will find a fairly good quality version here:
http://911research.wtc7.net/wtc/evidence/videos/index.html#northtower

It is titled North Tower collapse from northeast. The collapse initiates on the opposite side of the building, the upper block rotates away from the camera's view. This clip shows clearly that the part you talk about GregoryUrich, moves simultaneously with the upper part. That part of the exterior wall is hanging in the air, its columns was cut by Flight 11's left wing on floor 94. So when the reminder of the exterior columns on the north side buckle up and fails in the area of floor 97/98, this part of the wall is already free to move with the upper block. Just compare it to any photo of Flight 11's entry hole.

(By the way the claim in the text that the antenna moves one second before the facade is wrong, it moves simultaneously, but the top of antenna will show more movement because it is at the upper end of the rotating part, therefore movement in the antenna will be easier to spot initially. But what can we expect since this is a truther site.)

[Gravy]

Is the black line floor 97? Interesting that only part of the facade starts to collapse!Well, not quite. See the right side? Remember that the collapse began on the opposite side. It's helpful to see the whole top:

Cz6VxxVdXuA

[beachnut]

Well, not quite. See the right side? Remember that the collapse began on the opposite side. It's helpful to see the whole top:

Cz6VxxVdXuA
As Greg keeps posting, evidence of his lack of knowledge on 9/11 grows. I want him to post his independent paper, not a hack attack on a paper done to show something he does not even understand. He even falls for the cherry picked video cut.

[GregoryUrich]

Well, not quite. See the right side? Remember that the collapse began on the opposite side. It's helpful to see the whole top:

Cz6VxxVdXuA

I am aware it is the north side. A part, left middle, moves downward before the surrounding area of facade.

[beachnut]

I am aware it is the north side. A part, left middle, moves downward before the surrounding area of facade.
Is that your last hope for your silent explosives at work.

The entire top is moving down. Darn, you can image a floor failing inside but the whole top is coming down. So you are not correct. You are still a member of some 9/11 truth group, and you have peer group Journal cheering you on. The entire building is falling at the top, not some part in the middle; you mean to say the entire top is moving down!

If not you are going to remain wrong. What do you think; and how much can a floor hold? Cat got your tongue?

[Heiwa]

Heiwa wrote:

Thus we have you - Heiwa - admitting that aircraft hit each tower. And you claim that the impacts would have no effect on the tower whatsoever, even from the damage and fires they caused.

Why are you afraid to clear up your contradiction, Heiwa?

Sorry to see that you and your colleaugues still terrorize this thread.

Actually I was quoting the Nist report about air planes hitting the towers. No evidence for that, of course. And observed that the towers were still standing, etc. Plenty of evidence for that, though.

But the subject now is what happens at time Tcause more than an hour later in WTC1. Then it is suggested that the complete 'initiation zone' (IZ)(the area where the plane crashed and a fire burnt) suddenly disappears enabling the rigid mass above (RMA) to suddenly fall down the height of IZ and release its potential energy on the rigid structure below (RMB), that happens at time Teffect, i.e. RMA bumps into RMB.

When RMA bumps into RMB at time Teffect, you would expect that first there is a jolt or a little jerk or shake up, RMA slows down, before RMB disintegrates due to lack of strain energy, but none is seen.

Actually, apart from IZ that disappeared out of sight at time Tcause, also RMA seems to have disappeared before Teffect. Very strange cause and effect, to say the least.

Why can't Nist establish times Tcause and Teffect and provide us a time table for these events. And an explanation how IZ disappears (how?, where?), RMA falls down, its energy (easy to calculate), RMA disappears (how?, where?), the strain energy of RMB (easy to calculate), etc, etc.

It is very disturbing that Nist just produces nonsense - fairy tales - in its scientific report.

Don't blame the piano player if the music is bad. Nist produced the music and, I agree, it is awful.

[beachnut]

Sorry to see that you and your colleaugues still terrorize this thread.

Actually I was quoting the Nist report about air planes hitting the towers. No evidence for that, of course. And observed that the towers were still standing, etc. Plenty of evidence for that, though.

But the subject now is what happens at time Tcause more than an hour later in WTC1. Then it is suggested that the complete 'initiation zone' (IZ)(the area where the plane crashed and a fire burnt) suddenly disappears enabling the rigid mass above (RMA) to suddenly fall down the height of IZ and release its potential energy on the rigid structure below (RMB), that happens at time Teffect, i.e. RMA bumps into RMB.

When RMA bumps into RMB at time Teffect, you would expect that first there is a jolt or a little jerk or shake up, RMA slows down, before RMB disintegrates due to lack of strain energy, but none is seen.

Actually, apart from IZ that disappeared out of sight at time Tcause, also RMA seems to have disappeared before Teffect. Very strange cause and effect, to say the least.

Why can't Nist establish times Tcause and Teffect and provide us a time table for these events. And an explanation how IZ disappears (how?, where?), RMA falls down, its energy (easy to calculate), RMA disappears (how?, where?), the strain energy of RMB (easy to calculate), etc, etc.

It is very disturbing that Nist just produces nonsense - fairy tales - in its scientific report.

Don't blame the piano player if the music is bad. Nist produced the music and, I agree, it is awful.
This post has no basis in reality like your paper!

So how did they fool everyone to think they saw a plane hit?

[Dave Rogers]

This existence of unique "weld planes" separated by 3 floors is very important to know when modelling the towers, no?

Especially considering how column "failure" happened at these very welds.


For example, Einstein asks:

Dave, did you notice those rows of squibs, the distance between them is not exactly the distance of a story, but much more, I've noticed that also for a couple of other movies that I synchronized in time. This is a big contradiction for the theory that these are caused by falling floors. The same appears at the other side of the building in spite of the fact that the block topples, the floors cannot enclose the amount of air. The first row is above the mechanical floors, the 2nd is in the mechanical floors and the third below. There are a couple of other things also that doesn't fit the official story.

Maybe there is a relation?

Did you happen to notice my reply to Einsteen where I suggested exactly the same thing?

I really don't understand what you're trying to say here, MT. You've pointed out repeatedly that the core columns failed at the weld planes, which as far as I can see is a very important observation in understanding why the towers fell. However, all you can seem to infer is that the failures suggest something nefarious, rather than the obvious conclusion that the system failed at its weak points. As I've already said, this suggests that the collapse was more energitically favourable than Bazant's simplification suggests, so there is less, not more, need to invoke additional weakening mechanisms.

Dave

[Heiwa]

This post has no basis in reality like your paper!

So how did they fool everyone to think they saw a plane hit?

That was easy. Subject is how they fooled everyone to think that the initiation zone, IZ, suddenly disappeared an hour later and allowed the tower above to drop on the tower below.

Or, who convinced everyone that the potential energy of the mass above IZ exceeded the strain energy of the structure below and that this combination would cause the whole tower to disintegrate into 1000 000's of pieces.

It was Mr Bazant that within 48 hrs produced a scientific paper to this effect! No peer review, of course, in that short time ... and I wonder if the paper wasn't written 48 days before?

Anyway, the Bazant paper is just rubbish; assuming the mass above to be rigid to start with. It is not. Clearly seen on all videos. And then assuming that IZ disappears suddenly allowing free fall of mass above. The contrary is evidently seen on all videos.

And then these strange formulas about overload due to a rigid, instantaneous impact during one millisecond, when it is obvious that the mass above would just hang on to the top after having deformed IZ a little taking much longer, if it ever would happen.

I like the millisecond assumtion. Only an explosion could have produced the relevant energy in that time, which is 1000 times bigger than the release of potential energy from above = 40 kgs of diesel oil.

So you see beechnut - reality is sometimes painful. You see something on a video and you believe it is something else because it suits you.

That's why the efforts of G Urich should be applauded. It is only 64 months too late.

[peteweaver]

Bazant has a long history of researching creep, structural design and structural failiure.

He has enough knowledge and experience to write a speculative thesis on the collapses in 24 hours.

It just so happens that whilst he wasn't 100% right in every detail, his method was flawless, his logic and reasoning were correct, and the main point of his paper, that structural damage and fire brought about the collapses of the twin towers, is factually correct.

IF his paper was rubbish, it would have been rubbished by his peers (who possess the same level of SUBJECT RELAVENT qualifications, and similar hands on experience in the subject).

[e^n]

And then these strange formulas about overload due to a rigid, instantaneous impact during one millisecond, when it is obvious that the mass above would just hang on to the top after having deformed IZ a little taking much longer, if it ever would happen.

Could you restate? I don't think 'hang on to the top' makes much sense.

[uk_dave]

Bazant has a long history of researching, creep

Corrected that for you.

[bje]

Actually I was quoting the Nist report about air planes hitting the towers.

No, Heiwa, I bolded your words specifically:

"The Towers also survived the initial impacts of planes on 911 due to their redundancy."Now, you claim:
No evidence for that, of course. Thus you admit your paper is wrong, Heiwa. Tell us how you can claim in your paper that planes hit the towers and now tell us there is NO evidence that planes hit WTC 1 and WTC 2. How are you going to get out of this mess you created for yourself?

[Heiwa]

Could you restate? I don't think 'hang on to the top' makes much sense.

Is 'remain in location' clear enough? Anyway, the top cannot fall down, because there is no possibility that the structure below collapses. To little potential energy involved.

[Heiwa]

No, Heiwa, I bolded your words specifically:

Now, you claim:
Thus you admit your paper is wrong, Heiwa. Tell us how you can claim in your paper that planes hit the towers and now tell us there is NO evidence that planes hit WTC 1 and WTC 2. How are you going to get out of this mess you created for yourself?

??? I do not claim in my paper that the planes hit the towers - I just quote Nist stating that various plans apparentely impacted the towers ar various times. Why should I claim the opposite? If Nist claims it ... fair enough. It is not the topic we discuss = Gurich paper.

The important matter is, in this respect, that long time after impacts both towers suddenly collpsed for exactly the same - copy/paste - cause.

Two different towers, planes, impacts, different locations/angles, different fires, times but the cause is the same. Logical?

Of course not. Each incident must be analysed on its merits.

And as far WTC1 is concerned Nist conclusions do not tally with observations and science as Urich observes. Probably the same with WTC2 where the impact damage was much smaller.

As I have written a paper for children about WTC1 I participate in this discussion, because I find Urich findings useful ... and maybe I can improve them? Anyway, Urich has improved my paper.

[e^n]

Is 'remain in location' clear enough? Anyway, the top cannot fall down, because there is no possibility that the structure below collapses. To little potential energy involved.

Lets be fair, in your modelled scenario with your modelled failure modes it would appear there's not enough KE (I don't know why you say PE) to fail the next floor's columns. However in reality the top section did not directly descend and many columns were not involved in the collision. It sounds like you are making real life predictions off a rather dubious model?

[SDC]

So Heiwa, I believe you've been asked, and I hope I'm not missing something, but what about the people in the area who saw the planes hit the towers? We are not talking videos which are now available (which perhaps you think were doctored) but actual human individuals?

What about the people who have not been seen since that day? Where did they go? I knew two of them, personally, quite well; one in "Windows on the World," the other in a plane. I've spoken with the wife of the first, and the mother of the second, since. They have mourned.

Sorry to interject human concerns. But you keep talking about the children whom you've written for, so I figure I can bring up the victims.

[Heiwa]

Bazant has a long history of researching creep, structural design and structural failiure.

He has enough knowledge and experience to write a speculative thesis on the collapses in 24 hours.

It just so happens that whilst he wasn't 100% right in every detail, his method was flawless, his logic and reasoning were correct, and the main point of his paper, that structural damage and fire brought about the collapses of the twin towers, is factually correct.

IF his paper was rubbish, it would have been rubbished by his peers (who possess the same level of SUBJECT RELAVENT qualifications, and similar hands on experience in the subject).

Haste makes waste = rubbish, which Urich demonstrates well.

And you have still not understood what we discuss. Structural damage and fire didn't brought any collapse of the WTCs!!

So what brought collapse according Nist/Bazant? Apparently released potential energy at unknown time that exceeded strain energy in the structure at some other unknown time = some mysterious 'overload' a little later.

Bazant seems to have overstimated the potential energy several times and underestimated the strain energy in the structures and ignored all the times required for various events, etc. And assumes that the bodies involved are rigid when they volum wise are 95% air.

Bazant has not got anything right ... except that his result suited his Masters perfectly. Within 48 hrs. It stinks.

[Heiwa]

So Heiwa, I believe you've been asked, and I hope I'm not missing something, but what about the people in the area who saw the planes hit the towers? We are not talking videos which are now available (which perhaps you think were doctored) but actual human individuals?

What about the people who have not been seen since that day? Where did they go? I knew two of them, personally, quite well; one in "Windows on the World," the other in a plane. I've spoken with the wife of the first, and the mother of the second, since. They have mourned.

Sorry to interject human concerns. But you keep talking about the children whom you've written for, so I figure I can bring up the victims.

OT - we discuss what can have happened and be seen when the potential energy is released that caused the collapses according Nist. We discuss WTC1. Any witness of that is very welcome. It is a very short time frame. I base my analysis on videos. What happened before release of potential energy at time (cause) or after initiation of collapse of the structure below at time (effect) is OT in this thread.

Urich is only interested in this short time frame.

My interest is that children are being informed correctly.

[SDC]

As others have said, the matter of the planes is absolutely not OT. If you remove the planes, your whole engineering paper is bogus. Heck, it isn't engineering, it's fantasy. And as long as you keep justifying your fantasies with the kids... Your work is every bit as much fantasy as "Alice in Wonderland" only a lot less educational.

Except, perhaps, as an inoculation against the Stupids.

[Heiwa]

Lets be fair, in your modelled scenario with your modelled failure modes it would appear there's not enough KE (I don't know why you say PE) to fail the next floor's columns. However in reality the top section did not directly descend and many columns were not involved in the collision. It sounds like you are making real life predictions off a rather dubious model?

You refer to my paper? Max PE is 340 kWh if the WTC1 top drops 3.7 m in vacuum and contacts the structure below. For that all structure in the initiation zone, IZ, have disappeared, how I do not know. I just assume it isn't there.
Then I assume it is there, and that 0.5 PE is used up to crumble it and sweep it out of the way.
So 170 kWh is available when the WTC1 top above impacts the tower below. It is KE. Actually it is not an impact - it is a bump. You would now expect that there is a jolt indicating impact, but the videos doesn't show any jolt.
Anyway KE = 170 kWh can only compress the structure below a little - 0.2%. Should be elastic. And then the top above should bounce up again and remain in position. Some lose parts may fall down below beside the tower below.

Most people still in the top above would probably have survived that. And then NYFD could have extinguised the fire.

BUT - if you look at all videos, the top above actually disintegrates before any potential energy is released. No top part above ever impacts or bounces on the structure below the initiation zone. I am sorry to say. Clever planted disinformation actually.

So the people in the top above was apparently murdered a fraction of a second before the tower below also disintegrated. OT of course. We just discuss the alleged release of potential energy (that never took place) and its effects on the structure below (that would not collapse even if the release of potential energy took place).

[16.5]

"My interest is that children are being informed correctly."

Wait a second. And you are telling them No Planes hit the towers?

[Heiwa]

As others have said, the matter of the planes is absolutely not OT. If you remove the planes, your whole engineering paper is bogus. Heck, it isn't engineering, it's fantasy. And as long as you keep justifying your fantasies with the kids... Your work is every bit as much fantasy as "Alice in Wonderland" only a lot less educational.

Except, perhaps, as an inoculation against the Stupids.

It doesn't matter if planes or birds or butterflies impacted the towers.Those impacts (fantasy?) didn't cause the release of potential energy (engineering) much later. It is quite obvious and not Alice in Wonderland.

If you can prove that the potential energy released, as alleged by Nist, caused the collapse of the building below, you are welcome. In my paper for children I just show the opposite. And it is not fantasy.

Grow up!

[SDC]

OK, Heiwa, you have stated that the people near the top of the building were, somehow, murdered.

How about the people on the planes who have never been seen again? Murdered, given a new identity, what? Again, you are speaking to someone (me) who knew one of the people on the plane -- flt 75, if I recall correctly.

And I wasn't a witness of the events, except in the same way W. was -- TV. (I was at work, in Detroit.)

And again, this is not OT, because it's obvious to the meanest intelligence (and you meanest intelligences all know who you are) that planes hit the buildings and did some serious damage.

Assuming you are in Sweden, well, I weep for the Swedish children.

[Heiwa]

"My interest is that children are being informed correctly."

Wait a second. And you are telling them No Planes hit the towers?

Pls read the thread + my paper where it is quoted that planes impacted the towers. No big deal. But it could have been a butterfly!

Alice drops through a hole in the ground and arrives in Wonderland.

And in Wonderland many strange things happens.

One of them is that a child is jumping in a bed ... and, instead of bouncing up and down, the bed is destroyed and the child falls down, down, down and the bed goes into thousand of pieces and the child dies.

Many children get terrible dreams of such things. I tell them they do not happen in the real world. I tell them evil persons make up such bad things.

[Heiwa]

OK, Heiwa, you have stated that the people near the top of the building were, somehow, murdered.

How about the people on the planes who have never been seen again? Murdered, given a new identity, what? Again, you are speaking to someone (me) who knew one of the people on the plane -- flt 75, if I recall correctly.

And I wasn't a witness of the events, except in the same way W. was -- TV. (I was at work, in Detroit.)

And again, this is not OT, because it's obvious to the meanest intelligence (and you meanest intelligences all know who you are) that planes hit the buildings and did some serious damage.

Assuming you are in Sweden, well, I weep for the Swedish children.

To avoid discussing the people in the planes, we can assume they became butterflies. Wonderland, you know.

Don't cry for the children of Sweden, where I am not. Cry for the children of the USA who are actually living in Wonderland.

[16.5]

"One of them is that a child is jumping in a bed ... and, instead of bouncing up and down, the bed is destroyed and the child falls down, down, down and the bed goes into thousand of pieces and the child dies. Many children get terrible dreams of such things. I tell them they do not happen in the real world. I tell them evil persons make up such bad things."

Really, you are telling children that jumping up and down on beds can't cause them to collapse? I'll be damned. I guess that scar on my head from when I was 11 isn't there.

So you are both a No Planer and a No Bed Side Tabler too?

[stateofgrace]

I'm sorry maybe I misread it, but did Hiewa just say the top part of the buidling did not impact on the bottom part ? It missed it completly ?

Did he just say that? Honestly?

[Dave Rogers]

Many children get terrible dreams of such things. I tell them they do not happen in the real world. I tell them evil persons make up such bad things.

Tell them they don't need to look before they cross the road, either, because only evil persons make up stories of children being run over. And tell them it's OK to put their hands on the top of the cooker, and to accept sweets from strangers. Because the only evil people in your world are the ones who pretend that bad things sometimes happen, and we should all shield the little children from such things. In fact, the whole collapse of the WTC towers was just a story made up by evil people who want to scare the children...

But wait - you believe that happened though, don't you?

So you'll reassure the children that jumping up and down on their beds is perfectly safe, and you'll reassure them even more by telling them that their government is a group of infinitely powerful and infinitely evil people who will happily kill them and never get caught, because they'll convince the whole world that someone else did it? So that when they wake up in the night crying, you'll tell them that their nightmares are real, and that the bogeyman is out there, but that he's human, he wears a suit, and they'll never see him coming?

What a wonderful world your children must live in.

Dave

[Newtons Bit]

It doesn't matter if planes or birds or butterflies impacted the towers.Those impacts (fantasy?) didn't cause the release of potential energy (engineering) much later. It is quite obvious and not Alice in Wonderland.

If you can prove that the potential energy released, as alleged by Nist, caused the collapse of the building below, you are welcome. In my paper for children I just show the opposite. And it is not fantasy.

Grow up!

Unfortunately, your paper has had serious questions asked of it, which you have chosen to ignore.

To those in this thread who didn't follow that discussion, consider Heiwa's "paper" completely debunked.

[SDC]

This is simply incredible. Heiwa seems a courteous and articulate correspondent. Yet what he is proposing is appalling, disgusting, sick. Nauseating. The other no-planers generally seem much angrier and ruder. What a strange combination; courteous, articulate, presenting fantasies which are vile. I have a little difficulty with this combination of features. I think I had better leave.

[bje]

??? I do not claim in my paper that the planes hit the towers.

You did - until you removed the quote this morning.

Tell us, Heiwa, why did you remove the quote?

[Apollo20]

Heiwa:

Consider each WTC tower as being divided (mathematically) into upper and lower sections such that an upper mass Mu acts on a lower mass Ml and the mass of the tower Mt is thus [Mu + Ml]. In a normal, undamaged, tower the load acting on Ml is Mu .g. Then, for example, if we consider the upper mass to be say 50,000 tonnes, the downward-acting force on the top of the lower section is 50,000,000 kg x 9.8 m/s^2 ~ 500 MN. In the Twin Towers this load was shared more or less equally between the core and the perimeter columns.

Let us suppose that, under the compressive load of the upper section, the lower section of a tower acts like a giant spring and obeys Hooke’s Law. This means that the downward displacement, d, of the lower section due to the static weight of the upper section is proportional to the applied compressive force, Fu. This leads to the familiar result:

Fu = Mu. g = k.d,

where k is the stiffness, also called the spring constant, of the lower section of the tower.

Now since Young’s modulus, E, equals stress, s, divided by strain, the downward displacement of the top of the lower section of a tower due to static loading by mass Mu, is given by,

d = L. Mu .g /AE

where L is the length of the lower section and A is the effective cross sectional area of the structural steel.

Representative values of L and A would be 300 meters and 5 m^2, respectively, while E for structural steel is typically ~ 200 GPa. It follows that d is ~ 15 cm and since k is equal to Mu. g / d we have k = 3 GN/m. The elastic energy stored by this compression is (500 x 0.15) MJ or 75 MJ. Now since structural steel has an elastic strain energy capacity of 50 J/kg, the building can handle the weight of the upper section because the resulting strain energy is taken up by a large mass of steel below it. There was, in fact, at least 15,000,000 kg of structural steel available to support a 50,000,000 kg upper section, so we have 75 MJ of elastic strain energy per 15 x 10^6 kg or 5 J/kg which is well below the 50 J/kg elastic capacity of the structural steel.

Now consider what happens if there is a failure of a significant number of columns supporting a 50,000,000 kg upper section of a tower. Prior to such a failure we had a stable building in which the downward-acting force on the lower section was countered by an equal and opposite reaction force on the upper section. If the perimeter wall columns should suddenly fail at the interface between our upper and lower sections, the wall will unload some or all of the reaction force so that the downward-acting force now exceeds the reaction force acting on the upper section. This creates a net accelerating force on the upper section of the tower.

Data reported in NCSTAR 1-6D show that the total perimeter column load at the 83rd floor of WTC 2 was about 250 MN. It follows that after unloading by the perimeter columns at or near this floor, the upper section will move downwards under the action of this force with an acceleration, a, given by:

a = Force /Mass ~ 250 MN/50,000,000 = 5 m/s^2 ~ ½ g

Assuming that the upper section drops one story height or 3.7 meters, the stiffness, k, of the “spring” that held up the lower section of the tower has been reduced from 3 GN/m to 68 MN/m, (250 MN/3.7 m). We also note that the work done by the upper section in collapsing one floor, Wc, is given by:

Wc = Force x Distance = 250 MN x 3.7 m = 925 MJ

Now, since the loss in potential energy is Mu. g. h, we see that the amount of kinetic energy gained by the upper section after falling 3.7 meters is:

K.E. = (Mu. g. h) - Wc = (1813 – 925) MJ = 888 MJ

It follows from the equation K.E. = ½ Mu. v^2, that the upper section would be moving with a velocity v ~ 6 m/s after this 3.7 meter drop. It is interesting to note that Wc is identical to the quantity I have previously called E1 and the calculated value of 925 MJ given above is in good agreement with the range of values proposed for E1.

The real-world situation in the twin towers was, however, a little more complex than the simplified model described above because collapse initiation was actually caused by tipping of the upper section. Thus, considering the case of WTC 2, floor truss sagging and/or failures on the east side of this tower between the 80th and the 84th floors affected the lateral bracing between the core and the exterior of the building and led to an inward bowing of the east perimeter wall as seen in Figure 6-21 of NCSTAR 1-6. This bowing caused a measurable tipping of the upper section of WTC 2 that, according to NIST, had already lowered the east side of the upper section of the building by 30 cm about 15 minutes before total collapse started. The associated loss of potential energy by the upper section at this point in time is easily calculated to be about 75 MJ; this energy was converted into strain energy in the east perimeter wall columns because it created shear stresses in the upper and lower splices of these columns.

Just prior to collapse, the inward bowing of the east wall of WTC 2 was well over 50 cm so that the affected perimeter columns eventually failed in shear at the splice bolts. This created a net downward force on the east side of the upper section of WTC 2 that allowed it to tip 3.3 degrees before striking the floor below. However, at this point in time, ¾ of the perimeter wall at or near the 83rd floor - a wall that supported 50 % of the mass of the upper section of the building - would have been destroyed.

The kinetic energy imparted to the upper section of WTC 2 by this tipping motion was actually rotational kinetic energy, (RKE), and is given (approximately) by the formula:

RKE = 1/6 Mu. h^2. {d(theta)/dt}^2

where h is the height of the upper section and d(theta)/dt is the angular velocity in rads/s. Substituting appropriate values into this equation we find that the rotational kinetic energy imparted to the upper block of WTC 2 during the first second of collapse was at least 350 MJ. This would be more than sufficient to shear off many perimeter columns surrounding the floors immediately below the impact zone and so on all the way down the tower.

[beachnut]

That was easy. Subject is how they fooled everyone to think that the initiation zone, IZ, suddenly disappeared an hour later and allowed the tower above to drop on the tower below.

Or, who convinced everyone that the potential energy of the mass above IZ exceeded the strain energy of the structure below and that this combination would cause the whole tower to disintegrate into 1000 000's of pieces.

It was Mr Bazant that within 48 hrs produced a scientific paper to this effect! No peer review, of course, in that short time ... and I wonder if the paper wasn't written 48 days before?

Anyway, the Bazant paper is just rubbish; assuming the mass above to be rigid to start with. It is not. Clearly seen on all videos. And then assuming that IZ disappears suddenly allowing free fall of mass above. The contrary is evidently seen on all videos.

And then these strange formulas about overload due to a rigid, instantaneous impact during one millisecond, when it is obvious that the mass above would just hang on to the top after having deformed IZ a little taking much longer, if it ever would happen.

I like the millisecond assumtion. Only an explosion could have produced the relevant energy in that time, which is 1000 times bigger than the release of potential energy from above = 40 kgs of diesel oil.

So you see beechnut - reality is sometimes painful. You see something on a video and you believe it is something else because it suits you.

That's why the efforts of G Urich should be applauded. It is only 64 months too late.
All I have to say to you and Gregory, have great joy, you and Greg both believe in 9/11 truth. Greg needs more reality based guys like your and your no planes. Congratulations Greg, with peers like this you are on the winning team. Go forward and spread your information! (does anyone in 9/11 truth understand a model? Guess not)

You guys between you, have no idea how much the floor can hold and why that is the key. How much weight can the floor hold?

[Max Photon]

Given the assumptions, nice narrative.

[bje]

Heiwa,

We have this paper by you:

Non-animated Visualization Aids to Assist in Understanding the Demolitions of the World Trade Center Twin Towers (http://heiwaco.tripod.com/nist.htm) by Anders Bjorkman (Heiwa)

"This article describes the structure of the World Trade Center Twin Towers and what happens when the release of potential energy, due to downward movement of the mass above one of its supporting columns when buckling, exceeds the strain energy that can be absorbed by the same column below."Then we have this paper by "Anon" with the same title:

Non-animated Visualization Aids to Assist in Understanding the Demolitions of the World Trade Center Twin Towers. (http://www.journalof911studies.com/letters/e/VisualizationAidsWTCTowers.pdf) by Anon, November 27, 2007

"Abstract: The volume of jet fuel that remained in each of the World Trade Center Twin Towers after the initial fireballs on September 11, 2001, would fit into a mid-size U-Haul® rental truck."Are you "Anon", Heiwa?

[uk_dave]

Maybe 'Anon' is a pet name his mother gave him? JAQ

[rwguinn]

I would like to complement Heiwa on the smooth derail of this thread to something entirely more foolish...

[Heiwa]

Heiwa:

Consider each WTC tower as being divided (mathematically) into upper and lower sections such that an upper mass Mu acts on a lower mass Ml and the mass of the tower Mt is thus [Mu + Ml]. In a normal, undamaged, tower the load acting on Ml is Mu .g. Then, for example, if we consider the upper mass to be say 50,000 tonnes, the downward-acting force on the top of the lower section is 50,000,000 kg x 9.8 m/s^2 ~ 500 MN. In the Twin Towers this load was shared more or less equally between the core and the perimeter columns.

Let us suppose that, under the compressive load of the upper section, the lower section of a tower acts like a giant spring and obeys Hooke’s Law. This means that the downward displacement, d, of the lower section due to the static weight of the upper section is proportional to the applied compressive force, Fu. This leads to the familiar result:

Fu = Mu. g = k.d,

where k is the stiffness, also called the spring constant, of the lower section of the tower.

Now since Young’s modulus, E, equals stress, s, divided by strain, the downward displacement of the top of the lower section of a tower due to static loading by mass Mu, is given by,

d = L. Mu .g /AE

where L is the length of the lower section and A is the effective cross sectional area of the structural steel.

Representative values of L and A would be 300 meters and 5 m^2, respectively, while E for structural steel is typically ~ 200 GPa. It follows that d is ~ 15 cm and since k is equal to Mu. g / d we have k = 3 GN/m. The elastic energy stored by this compression is (500 x 0.15) MJ or 75 MJ. Now since structural steel has an elastic strain energy capacity of 50 J/kg, the building can handle the weight of the upper section because the resulting strain energy is taken up by a large mass of steel below it. There was, in fact, at least 15,000,000 kg of structural steel available to support a 50,000,000 kg upper section, so we have 75 MJ of elastic strain energy per 15 x 10^6 kg or 5 J/kg which is well below the 50 J/kg elastic capacity of the structural steel.

Now consider what happens if there is a failure of a significant number of columns supporting a 50,000,000 kg upper section of a tower. Prior to such a failure we had a stable building in which the downward-acting force on the lower section was countered by an equal and opposite reaction force on the upper section. If the perimeter wall columns should suddenly fail at the interface between our upper and lower sections, the wall will unload some or all of the reaction force so that the downward-acting force now exceeds the reaction force acting on the upper section. This creates a net accelerating force on the upper section of the tower.

Data reported in NCSTAR 1-6D show that the total perimeter column load at the 83rd floor of WTC 2 was about 250 MN. It follows that after unloading by the perimeter columns at or near this floor, the upper section will move downwards under the action of this force with an acceleration, a, given by:

a = Force /Mass ~ 250 MN/50,000,000 = 5 m/s^2 ~ ½ g

Assuming that the upper section drops one story height or 3.7 meters, the stiffness, k, of the “spring” that held up the lower section of the tower has been reduced from 3 GN/m to 68 MN/m, (250 MN/3.7 m). We also note that the work done by the upper section in collapsing one floor, Wc, is given by:

Wc = Force x Distance = 250 MN x 3.7 m = 925 MJ

Now, since the loss in potential energy is Mu. g. h, we see that the amount of kinetic energy gained by the upper section after falling 3.7 meters is:

K.E. = (Mu. g. h) - Wc = (1813 – 925) MJ = 888 MJ

It follows from the equation K.E. = ½ Mu. v^2, that the upper section would be moving with a velocity v ~ 6 m/s after this 3.7 meter drop. It is interesting to note that Wc is identical to the quantity I have previously called E1 and the calculated value of 925 MJ given above is in good agreement with the range of values proposed for E1.

The real-world situation in the twin towers was, however, a little more complex than the simplified model described above because collapse initiation was actually caused by tipping of the upper section. Thus, considering the case of WTC 2, floor truss sagging and/or failures on the east side of this tower between the 80th and the 84th floors affected the lateral bracing between the core and the exterior of the building and led to an inward bowing of the east perimeter wall as seen in Figure 6-21 of NCSTAR 1-6. This bowing caused a measurable tipping of the upper section of WTC 2 that, according to NIST, had already lowered the east side of the upper section of the building by 30 cm about 15 minutes before total collapse started. The associated loss of potential energy by the upper section at this point in time is easily calculated to be about 75 MJ; this energy was converted into strain energy in the east perimeter wall columns because it created shear stresses in the upper and lower splices of these columns.

Just prior to collapse, the inward bowing of the east wall of WTC 2 was well over 50 cm so that the affected perimeter columns eventually failed in shear at the splice bolts. This created a net downward force on the east side of the upper section of WTC 2 that allowed it to tip 3.3 degrees before striking the floor below. However, at this point in time, ¾ of the perimeter wall at or near the 83rd floor - a wall that supported 50 % of the mass of the upper section of the building - would have been destroyed.

The kinetic energy imparted to the upper section of WTC 2 by this tipping motion was actually rotational kinetic energy, (RKE), and is given (approximately) by the formula:

RKE = 1/6 Mu. h^2. {d(theta)/dt}^2

where h is the height of the upper section and d(theta)/dt is the angular velocity in rads/s. Substituting appropriate values into this equation we find that the rotational kinetic energy imparted to the upper block of WTC 2 during the first second of collapse was at least 350 MJ. This would be more than sufficient to shear off many perimeter columns surrounding the floors immediately below the impact zone and so on all the way down the tower.

Very good. You understand what we are talking about. In my paper I focus only on WTC1, which is of course completely different from WTC2.

And there I show that the top of WTC1 cannot destroy the part below the so called initiation zone, IZ, for many reasons.

You say - and I adapt for WTC1

"Now consider what happens if there is a failure of a significant number of columns supporting a 33 000 000 kg upper section of a tower. Prior to such a failure we had a stable building in which the downward-acting force on the lower section was countered by an equal and opposite reaction force on the upper section. "

This I do. Evidently a significant number of columns are not seen failing at all before the roof starts to drop, but I allow it to happen.

The official cause is that all columns fail simultaneously to release potential energy.

And there will be no collapse. Too little energy to do any big damage just below the initiation zone ... and little energy still available to destroy the complete building below.

If you read my article carefully you should know the importance of time of cause (release of potential energy when all columns fail) and the time of effect (impact and start of global collapse). These times should be established from videos. Nist doesn't bother to make a proper time table. Bad.

Too much unexplained things happen before the time of cause! Nothing should happen above IZ but it happens. Actually the top part is seen disintegrating before the columns at IZ fails = time of cause. This disturbs me a lot.

The time difference between cause and effect should be very short and then there should be a little pause, so to say. The top part should 'bounce' against the structure below. Doesn't happen. Thus no impact!! This is serious.

But again, I see debris flying out of windows before time of cause! Because the wall columns all around are intact.

Too much energy is then released too quickly, so to say. There was no impact. From where then comes the energy? No release of potential energy has started. An explosion? Probably. It looks lite that.

You describe a lot of events, things being unloaded (sic), loads moving around, no explanations given ... and no times.

Come back - we discuss only WTC1 - with a complete time table for what you can see on the videos and how it tallies with the official only cause and only effect. You will see that 100% of what Nist suggests is ... Alice in Wonderland. There anything happens and time ... it goes forward and backwards to suit.

But thanks for your posting. Maybe you should apply for a job with Nist?

[Heiwa]

Heiwa,

We have this paper by you:

Non-animated Visualization Aids to Assist in Understanding the Demolitions of the World Trade Center Twin Towers (http://heiwaco.tripod.com/nist.htm) by Anders Bjorkman (Heiwa)

Then we have this paper by "Anon" with the same title:

Non-animated Visualization Aids to Assist in Understanding the Demolitions of the World Trade Center Twin Towers. (http://www.journalof911studies.com/letters/e/VisualizationAidsWTCTowers.pdf) by Anon, November 27, 2007

Are you "Anon", Heiwa?

No - same title of papers only, different authors. Different web sites. No connection. Quite clear actually for the normal reader.

[funk de fino]

heiwa

i am not a structural engineer and even i see your paper is the biggest load of junk i have ever seen posted on this site as a supposed credible paper

no planers are despicable human beings and they are normally low intelligence. you are quite clearly not un-intelligent but you seem to have a medical condition that has warped your reality and overidden your intelligence

please take your sick junk to truther sites and stop spamming threads which had great promise with your fantasy childish rubbish

you are what the truthers would call disinfo

you should apologize to Gregory Urich

[bje]

No - same title of papers only, different authors. Different web sites. No connection. Quite clear actually for the normal reader.

Interesting that you chose the same title.

Why did you remove this quote from your paper this morning and pretend it wasn't there, Heiwa?

"The Towers also survived the initial impacts of planes on 911 due to their redundancy."
Why are you afraid that you had admitted the planes hit the towers in your paper, Heiwa?

[DGM]

Did Heiwa just call Apollo20 a NISTian in that post. Now that's funny.

[Apollo20]

Heiwa:

The tipping of the upper section of WTC 1 to the south is key to the collapse of this tower too. Unfortunately many of the better known videos of the collapse of WTC 1 are taken from the north and do not reveal the true extent of the tipping. However, there are a few videos out there that show the tipping of the antenna quite nicely. I would say that these videos allow one to estimate that the upper section of WTC 1 had tilted by about 3 degrees just 2 seconds after collapse initiation at which point the upper section had dropped about 12 meters. (Free fall would give 20 meters of drop). So you need to include a dropping motion AND a rotational motion to properly analyse the first few seconds of the collapse of WTC 1. A video that shows the collapse from the north is almost useless in this regard because it obscures the tilting motion which is usually interpreted as a dropping motion.

[Major_Tom]

Dave, if you recall, I asked some pretty straightforward questions in the following argument:

Argument #1:


Let's consider the head-on collision after a 12 foot fall of a typical core column, Column 1003, shown below.

http://www.sharpprintinginc.com/911_math/column1003.jpg




In the case of the North Tower, Bazant's "upper block" portion of the column will only be the first 5 I-beam sections shown in the diagram above connected end to end.

The largest and strongest 37 column sections shown, connected end to end, constitute the ""lower block".



Now we ram the two parts together.



We know that the large, large majority of core box columns failed at weld connections before suffering any permanent distortion.



Just based on the principle that bigger tends to be stronger, where would you think the first weld breakage would occur just after impact?


Wouldn't the welds in the "upper block" tend to fail first?



And I believe you answered:

your entire approach here is bizarre. You're trying to dispute my assertion that the Bazant model is oversimplified by claiming that the Bazant model is oversimplified. This is what's known as "being in violent agreement".


I am saying that his application of a spring-mass model is a cartoon.

You say "oversimplification" and then you proceed to extract data you claim is useful.



I don't mean to single you out, it's just that you seemed to be able to give fair answers to previous questions.


So I'll assume your answer to my question is that all things being equal, we should expect the uppermost, weakest welds to fail first in the collision.

This, of course, would mean that you would guess that the upper block which is "crushing down" would very quickly lose it's rigidity. The strongest columns in the core of the upper block would split into their component parts and lose their structural rigidity.

Is that correct?

[Heiwa]

Heiwa:

The tipping of the upper section of WTC 1 to the south is key to the collapse of this tower too. Unfortunately many of the better known videos of the collapse of WTC 1 are taken from the north and do not reveal the true extent of the tipping. However, there are a few videos out there that show the tipping of the antenna quite nicely. I would say that these videos allow one to estimate that the upper section of WTC 1 had tilted by about 3 degrees just 2 seconds after collapse initiation at which point the upper section had dropped about 12 meters. (Free fall would give 20 meters of drop). So you need to include a dropping motion AND a rotational motion to properly analyse the first few seconds of the collapse of WTC 1. A video that shows the collapse from the north is almost useless in this regard because it obscures the tilting motion which is usually interpreted as a dropping motion.

I have just calculated the total potential energy released involved assuming all columns fail simultaneously as per Nist and a vertical drop. If some columns do not fail there is evidently no potential energy released there and there may be some rotation - but I cannot see any big rotation.

The vertical drop should start when all columns in the initiation zone fails, but it does not seem to be the case. The roof drops first - vertically.

However - let's assume that only half the columns on one side fails and the tower tilts. Why would global collapse then occur? The mass above is restrained to drop by the other half of columns.

So the tilting tower impacts on the structure below ... and should still bounce. Only half the energy is released, absorbed as compression and then stopped. Then the other half drops down on the other side, the rest of the energy is released after two seconds and the same thing happens. No collapse. Very good actually to spread out the release of energy over longer time because then the possibility to overload the structure is reduced considerably.

Thanks for pointing out that there is not ONE sudden impact on the structure below but TWO or more, smaller ones separated by 2 or more seconds. Another reason for no global collapse to ensue.

[funk de fino]

I have just calculated the total potential energy released involved assuming all columns fail simultaneously as per Nist and a vertical drop. If some columns do not fail there is evidently no potential energy released there and there may be some rotation - but I cannot see any big rotation.

The vertical drop should start when all columns in the initiation zone fails, but it does not seem to be the case. The roof drops first - vertically.

However - let's assume that only half the columns on one side fails and the tower tilts. Why would global collapse then occur? The mass above is restrained to drop by the other half of columns.
So the tilting tower impacts on the structure below ... and should still bounce. Only half the energy is released, absorbed as compression and then stopped. Then the other half drops down on the other side, the rest of the energy is released after two seconds and the same thing happens. No collapse. Very good actually to spread out the release of energy over longer time because then the possibility to overload the structure is reduced considerably.

Thanks for pointing out that there is not ONE sudden impact on the structure below but TWO or more, smaller ones separated by 2 or more seconds. Another reason for no global collapse to ensue.

This guy is not for real surely?

[Dave Rogers]

So I'll assume your answer to my question is that all things being equal, we should expect the uppermost, weakest welds to fail first in the collision.

This, of course, would mean that you would guess that the upper block which is "crushing down" would very quickly lose it's rigidity. The strongest columns in the core of the upper block would split into their component parts and lose their structural rigidity.

Please feel free to attribute to me any opinions you would care to list about the finely detailed predictions of a model which I have already said is too simplified to make any such predictions, if it makes you happy. They may not have any relation to my actual opinions about the collapse mechanism, but don't let that get in the way of you fantasising that I'm the interlocutor in your Socratic argument.

Dave

[Apollo20]

Heiwa,

The upper sections of both towers tip, AND CONTINUE TO TIP for the first few seconds of the collapse. There is no bounce! Why not? Because the perimeter columns in the impact zone fail. Why do they fail? Mainly because the impact forces are not vertical, but off-axis by about 3 degrees. This imposes lateral forces on columns that fail in shear, NOT COMPRESSION. (The columns were not designed to take lateral impact forces!) Eventually the columns that form the rotational hinge also fail, and the collapse takes on a strictly vertical motion. At this point Bazant's crush-down model becomes a good approximation to the dynamics of the remaining collapse.

[Newtons Bit]

Heiwa,

The upper sections of both towers tip, AND CONTINUE TO TIP for the first few seconds of the collapse. There is no bounce! Why not? Because the perimeter columns in the impact zone fail. Why do they fail? Mainly because the impact forces are not vertical, but off-axis by about 3 degrees. This imposes lateral forces on columns that fail in shear, NOT COMPRESSION. (The columns were not designed to take lateral impact forces!) Eventually the columns that form the rotational hinge also fail, and the collapse takes on a strictly vertical motion. At this point Bazant's crush-down model becomes a good approximation to the dynamics of the remaining collapse.

Dr. Greening, Heiwa isn't exactly grounded in reality. He does things like convert the potential energy of the block above into equivalent liters of gasoline, then conclude that this amount of gasoline isn't significant and thus couldn't damage anything like steel. He didn't actually do real calculations.

I've directed him to the calculations I've done on this strength, after which he put me on ignore for me an "imposter" because my numbers, though calculated correctly, conflict with his opinion of reality.

Remember the columns will fail from axial impacts only, even with (3) - 90 degree plastic hinges.

[Heiwa]

Heiwa,

The upper sections of both towers tip, AND CONTINUE TO TIP for the first few seconds of the collapse. There is no bounce! Why not? Because the perimeter columns in the impact zone fail. Why do they fail? Mainly because the impact forces are not vertical, but off-axis by about 3 degrees. This imposes lateral forces on columns that fail in shear, NOT COMPRESSION. (The columns were not designed to take lateral impact forces!) Eventually the columns that form the rotational hinge also fail, and the collapse takes on a strictly vertical motion. At this point Bazant's crush-down model becomes a good approximation to the dynamics of the remaining collapse.

It doesn't matter how the columns in the initiation zone failed because ... it is not the topic. Whatever happens before the time of cause - release of potential energy - is not the subject of my article or Urich's paper.

It is what happen after the time of cause = the release of potential energy. And you agree - vertical motion of the mass above.

I have calculated how much that potential energy is. Bazant and Nist didn't do that correctly.

When there is a collision between two bodies, in this case at the time of effect (the collision), which takes place at very low speed you would expect the speed of the impacting body to slow down! Either to zero and bounce back (negative velocity!) or at a much reduced speed. No such deceleration is observed = there was no impact.

Then Bazant and Nist suggest that this energy exceeds the strain energy of the structure without really calculate the strain energy or doing it incorrectly.

I show in my article that the energy applied to the structure below will temporily compress it a little (using a spring as example, like Bazant) and concludes that no global collapse ensues. Too little potential energy. Urich does the same using another way but in principle Urich and I use the same basic methods.

Nist has retracted from the release of potential energy cause and suggests now that some floors fell down and caused global collapse.

To be frank - that explanation (and Nist) is unscientific garbish straight from Alice in Wonderland.

Ask Nist if anybody peer reviewed their FAQs December 2007. They will not answer. They hide behind a dark veil.

I wonder why all these strange signatures above wonder about me personally. They should wonder about the findings in the papers ... and evidently about themselves. Why do they believe in Alice and Santa Claus?

[beachnut]

It doesn't matter how the columns in the initiation zone failed because ... it is not the topic. Whatever happens before the time of cause - release of potential energy - is not the subject of my article or Urich's paper.

It is what happen after the time of cause = the release of potential energy. And you agree - vertical motion of the mass above.

I have calculated how much that potential energy is. Bazant and Nist didn't do that correctly.

When there is a collision between two bodies, in this case at the time of effect (the collision), which takes place at very low speed you would expect the speed of the impacting body to slow down! Either to zero and bounce back (negative velocity!) or at a much reduced speed. No such deceleration is observed = there was no impact.

Then Bazant and Nist suggest that this energy exceeds the strain energy of the structure without really calculate the strain energy or doing it incorrectly.

I show in my article that the energy applied to the structure below will temporily compress it a little (using a spring as example, like Bazant) and concludes that no global collapse ensues. Too little potential energy. Urich does the same using another way but in principle Urich and I use the same basic methods.

Nist has retracted from the release of potential energy cause and suggests now that some floors fell down and caused global collapse.

To be frank - that explanation (and Nist) is unscientific garbish straight from Alice in Wonderland.

Ask Nist if anybody peer reviewed their FAQs December 2007. They will not answer. They hide behind a dark veil.

I wonder why all these strange signatures above wonder about me personally. They should wonder about the findings in the papers ... and evidently about themselves. Why do they believe in Alice and Santa Claus?
Yep, you got us with the Alice stuff and how could Santa be more cogent than your fantasy BS junk. This one post is so stupid even some 5th grade students can see your FRAUD. Frank was being nice to you and your fantasy junk science failure.

[funk de fino]

heiwa

Please define what you mean by "garbish"?

Is it garbage you mean to say?

If so, your paper is full of it

[twinstead]

I wonder why all these strange signatures above wonder about me personally. They should wonder about the findings in the papers ... and evidently about themselves. Why do they believe in Alice and Santa Claus?

And these highly-regarded, internationally known experts who contributed to the NIST would rightly look you square in the eye and tell you that you're nuts and you don't have a clue what you're talking about.

The only thing they would wonder about is how somebody who isn't fit to clean their chalkboards would be so arrogant.

[Belz...]

When there is a collision between two bodies, in this case at the time of effect (the collision), which takes place at very low speed you would expect the speed of the impacting body to slow down! Either to zero and bounce back (negative velocity!) or at a much reduced speed. No such deceleration is observed = there was no impact.

Yeah... slow speeds. I guess those mechanical presses don't really exist, because if they did they'd bounce back because of the speed...

[beachnut]

When there is a collision between two bodies, in this case at the time of effect (the collision), which takes place at very low speed you would expect the speed of the impacting body to slow down! Either to zero and bounce back (negative velocity!) or at a much reduced speed. No such deceleration is observed = there was no impact.

I show in my article that the energy applied to the structure below will temporily compress it a little (using a spring as example, like Bazant) and concludes that no global collapse ensues. Too little potential energy. Urich does the same using another way but in principle Urich and I use the same basic methods.
You are posting stupid statements. The slow moving mass is not going to slow down because you the floating boat man forgot we are not floating but falling. The slow mass is really an accelerating mass. You ignore GRAVITY. This statement of slow really applies to your ideas on 9/11!

Urich is a 9/11 truth member, he is bias, he has not completed his model, he attacks a model which shows it is possible! He is a fool he has over looked the key; how much can a floor hold (he can't tell you). The floors hold the WTC together, if you destroy a floor, you destroy the WTC strength. Greg is a 9/11 truth member he is looking at a cross sectional strength for the destruction of the WTC. He will fail, because his model has to have EXPLOSIVES/THERMITE, there were no explosives (Jones made up thermite, and Greg joined his group of misleading 9/11 truthers), just Greg seeing things. Greg has no idea what to do next, and it is funny as you think he has something you can point to as fact, as he knows your paper is junk as he showed you.

[Heiwa]

The floors hold the WTC together, if you destroy a floor, you destroy the WTC strength.

Exactly - this is what the Nist experts and highly-regarded, internationally known experts who contributed to the NIST suggest in the amazing Nist FAQ December 2007.

One (or more) floor drops down and the whole tower collapses.

The walls were just there to put windows in. And the columns had no real purpose.

Forget butterflies colliding with the towers, fires, release of potential energy, strain energy of the structure.

Beachnut, I am impressed. Your contribution here is really helpful. Like Belznut's, twinsnut's, funknut's, Davenut's, bjenut's, statenut's, 16.5nut's. Very high intellectual standard. Nutty! Now I understand why you believe planes actually hit the towers in the first place. You have watched too much television.

[Newtons Bit]

The walls were just there to put windows in. And the columns had no real purpose.

Remember folks, Heiwa's analogy of the WTC is a birdcage. He has no concept of how the floors give 100% of the stability to the columns.

[uk_dave]

Remember folks, Heiwa's analogy of the WTC is a birdcage. He has no concept of how the floors give 100% of the stability to the columns.

Don't worry. I think most people here are fully aware of what Heiwa doesn't know.

[beachnut]

Exactly - this is what the Nist experts and highly-regarded, internationally known experts who contributed to the NIST suggest in the amazing Nist FAQ December 2007. Sources? Just hearsay?

One (or more) floor drops down and the whole tower collapses. Oops, it was 12 and 28, or so. You need to study the WTC more so you do not make order of magnitude errors.

The walls were just there to put windows in. And the columns had no real purpose. The WTC was a system, you need to study more and stop making silly statements.

Forget butterflies colliding with the towers, fires, release of potential energy, strain energy of the structure. That is what you did in your paper?

Beachnut, I am impressed. Your contribution here is really helpful. Like Belznut's, twinsnut's, funknut's, Davenut's, bjenut's, statenut's, 16.5nut's. Very high intellectual standard. Nutty! Now I understand why you believe planes actually hit the towers in the first place. You have watched too much television. Actually I have read your paper and shown you few major, gross errors. Other have show you more. Why do you ignore them? Your paper is not correct. Even your 9/11 truth movement member support, Gregory, knows you paper is incorrect.

[Major_Tom]

Sorry, Dave. I didn't mean to focus on you. I assumed you would be able to give an answer.

The simple question was:

We know that the large, large majority of core box columns failed at weld connections before suffering any permanent distortion.



Just based on the principle that bigger tends to be stronger, where would you think the first weld breakage would occur just after impact?


Wouldn't the welds in the "upper block" tend to fail first?


I can understand why a person trying to defend a model which uses an "upper block" to "crush a lower block" would want to avoid the fact that the weakest welds in the colliding columns are in the upper block, not the lower block.

Since no one seems able to address Argument #1, I'll temporarily summerize the first argument as follows:


The Bazant model is wrong to apply a spring-mass, upper block-lower block model to the WTC "collapses".

They failed to recognize that the impacting columns themselves contain 41 weld points, the weakest of which will most probably be in the UPPER block.

They failed to recognize that overwhelming forensic evidence shows that core box column clearly separated from one another along weld surfaces and only a small minority of them were seen to have suffered any permanent plastic deformation at all.

Therefore the impact between the relatively massive lower column with the much smaller upper column, with it's relatively weaker weld nodes, would likely lead to the shattering of the upper column into smaller components along weld nodes before any permanent plastic deformation takes place.


End of argument #1.


A mental knee-jerk reaction to the reality of weld "failure" is that this means the towers would fall even easier that Bazant anticipated, hence "inevitable and total" failure is to be expected all the more.

But when we examine the physical characteristics of the "collapses" of WTC 1 and 2 and see that core box column weld "failure" must have occurred in a systematic, top-down fashion to explain the observed phenomena, we will notice some serious problems with a systematic top-down rapid collapse based on progressive "weld failure".

[stateofgrace]

Exactly - this is what the Nist experts and highly-regarded, internationally known experts who contributed to the NIST suggest in the amazing Nist FAQ December 2007.

One (or more) floor drops down and the whole tower collapses.

The walls were just there to put windows in. And the columns had no real purpose.

Forget butterflies colliding with the towers, fires, release of potential energy, strain energy of the structure.

Beachnut, I am impressed. Your contribution here is really helpful. Like Belznut's, twinsnut's, funknut's, Davenut's, bjenut's, statenut's, 16.5nut's. Very high intellectual standard. Nutty! Now I understand why you believe planes actually hit the towers in the first place. You have watched too much television.

Please stop posting.

Just stop.

[funk de fino]

Sorry, Dave. I didn't mean to focus on you. I assumed you would be able to give an answer.

The simple question was:




I can understand why a person trying to defend a model which uses an "upper block" to "crush a lower block" would want to avoid the fact that the weakest welds in the colliding columns are in the upper block, not the lower block.

Since no one seems able to address Argument #1, I'll temporarily summerize the first argument as follows:

The Bazant model is wrong to apply a spring-mass, upper block-lower block model to the WTC "collapses".

They failed to recognize that the impacting columns themselves contain 41 weld points, the weakest of which will most probably be in the UPPER block.

They failed to recognize that overwhelming forensic evidence shows that core box column clearly separated from one another along weld surfaces and only a small minority of them were seen to have suffered any permanent plastic deformation at all.
Therefore the impact between the relatively massive lower column with the much smaller upper column, with it's relatively weaker weld nodes, would likely lead to the shattering of the upper column into smaller components along weld nodes before any permanent plastic deformation takes place.


End of argument #1.


A mental knee-jerk reaction to the reality of weld "failure" is that this means the towers would fall even easier that Bazant anticipated, hence "inevitable and total" failure is to be expected all the more.

But when we examine the physical characteristics of the "collapses" of WTC 1 and 2 and see that core box column weld "failure" must have occurred in a systematic, top-down fashion to explain the observed phenomena, we will notice some serious problems with a systematic top-down rapid collapse based on progressive "weld failure".


How many and who inspected them to assess they had NO deformation at all?

How much deformation would have been needed before a weld broke?

I am not being arsey here I would just like to know where you got this information from.

[Gravy]

How many and who inspected them to assess they had NO deformation at all?

How much deformation would have been needed before a weld broke?

I am not being arsey here I would just like to know where you got this information from.Being a dishonest person, Major Tom knows he's wrong but chooses to repeat this claim anyway.

Most of the core columns recovered were significantly deformed, which made it difficult to select undeformed regions to harvest test specimens from. Even the relatively straight sections were often slightly bent.

NIST NCSTAR 1-3D "Mechanical properties of structural steel," page 48 (82 in the PDF).

[DGM]

Sorry, Dave. I didn't mean to focus on you. I assumed you would be able to give an answer.

The simple question was:




I can understand why a person trying to defend a model which uses an "upper block" to "crush a lower block" would want to avoid the fact that the weakest welds in the colliding columns are in the upper block, not the lower block.

Since no one seems able to address Argument #1, I'll temporarily summerize the first argument as follows:


The Bazant model is wrong to apply a spring-mass, upper block-lower block model to the WTC "collapses".

They failed to recognize that the impacting columns themselves contain 41 weld points, the weakest of which will most probably be in the UPPER block.

They failed to recognize that overwhelming forensic evidence shows that core box column clearly separated from one another along weld surfaces and only a small minority of them were seen to have suffered any permanent plastic deformation at all.

Therefore the impact between the relatively massive lower column with the much smaller upper column, with it's relatively weaker weld nodes, would likely lead to the shattering of the upper column into smaller components along weld nodes before any permanent plastic deformation takes place.


End of argument #1.


A mental knee-jerk reaction to the reality of weld "failure" is that this means the towers would fall even easier that Bazant anticipated, hence "inevitable and total" failure is to be expected all the more.

But when we examine the physical characteristics of the "collapses" of WTC 1 and 2 and see that core box column weld "failure" must have occurred in a systematic, top-down fashion to explain the observed phenomena, we will notice some serious problems with a systematic top-down rapid collapse based on progressive "weld failure".
Tell you what, Why don't you put together a start to finish analysis in the form of a written paper and we will get back to you.

In other words, Get to the point!!!!!!! you've been beating around the bush for months now, Present your hypothesis so we can move on.

[CHF]

Remember folks, Heiwa's analogy of the WTC is a birdcage. He has no concept of how the floors give 100% of the stability to the columns.

Judy Wood, Richard Gage, now Heiwa....

If these people don't understand buildings, no one does.

:dl:

[bje]

Nutty! Now I understand why you believe planes actually hit the towers in the first place. You have watched too much television.


...just refer to quotations from Chairman Heiwa's Little Red Book on 9/11:

There is clear (negative) evidence that no hijacked airplanes were involved in 911:
...
Conclusions (based on negative evidence):

A. The alleged hijacked planes did not crash at the various sites.
B. Whatever caused damage at the various crash sites was not a hijacked airplane.
http://www.911blogger.com/node/2406?page=1


"But it is OT. Topic is WTC1 design, construction and strength to resist collapse. WTC 1 resisted a plane crash. It resisted a big fire. Then the fire got smaller."
http://forums.randi.org/showpost.php?p=3287741&postcount=139


"The evidence for my 'theory' is there for anybody to watch on the videos. I doubt there is any testimony of people to the contrary."
http://forums.randi.org/showpost.php?p=3301945&postcount=168


"This is clear from the initial hole caused by the plane. In that case the mass above is carried by the intact bars around the hole in the wall and at the core and no potential energy was released."
http://www.flashback.info/showpost.php?p=9354844&postcount=7362


9/11/01 I was at Freiberg, Saxony, Germany. My daughter called and asked me to watch TV news. But we had no TV in our old house built 1590 ca. Only later I had the opportunity to watch the 911 crash sites on video.


"And it was quite evident to me that due to lack of any airplane wreckage anywhere that no airplanes ever caused the incidents. Furthermore - the structural damages at WTC and Pentagon and the hole in the ground at Pennsylvania cannot have been caused by airplanes for more reasons than that there are no airplane wreckage parts anywhere."
http://www.911blogger.com/node/2406#comment-64389


"You ask: What moments are developed in the exterior columns due to adjacent columns failing? Answer - look at the hole in the wall after the plane impact."
http://forums.randi.org/showpost.php?p=3287270&postcount=110
Any questions, class?

[Heiwa]

...just refer to quotations from Chairman Heiwa's Little Red Book on 9/11:


Any questions, class?

You better study my article again. I have added some links and ... BTW. No plane hit WTC1 and started the fire. Quite obvious, actually, even if not the topic of it. But it makes sense.

No plane hit WTC1, so fire was started by other means. One purpose was to knock out the cables to the television mast on the roof, so that local NY TV companies could not transmit the 'show' that followed. Only the five big ones, sharing the same control room, transmitted the 'show'. Hollywood live.

So if no plane hit WTC1 and only damage was externally due to - you know, I am sure that the core columns were not damaged at all.

And that explains the strange release of potential energy that followed, etc. according Nist.

There was no release of potential energy. Quite clear from the article, and we now know why.

Thanks for your assistance.

You can now apply for jobs as prison guards at the concentration camps being opened this summer all over USA.

[beachnut]

You better study my article again. I have added some links and ... BTW. No plane hit WTC1 and started the fire. Quite obvious, actually, even if not the topic of it. But it makes sense.

No plane hit WTC1, so fire was started by other means. One purpose was to knock out the cables to the television mast on the roof, so that local NY TV companies could not transmit the 'show' that followed. Only the five big ones, sharing the same control room, transmitted the 'show'. Hollywood live.

So if no plane hit WTC1 and only damage was externally due to - you know, I am sure that the core columns were not damaged at all.

And that explains the strange release of potential energy that followed, etc. according Nist.

There was no release of potential energy. Quite clear from the article, and we now know why.

Thanks for your assistance.

You can now apply for jobs as prison guards at the concentration camps being opened this summer all over USA.
Sorry, that only happens in Europe, our concentration camps, like our torture are a joke. Camp Grenada is our only concentration camp and it was exposed years ago, when I was a kid.

No plane, guess the people who saw the plane, and the radar track are Wrong? You ideas are pure nuts! NUTS, the 101 used that with the Germans in 1944, and it fits with your ideas. NUTS, bye bye

[Gravy]

Heiwa, I've spent time in Beausoleil. I stayed at the home of the harbor master for a few days.* The sun is indeed very nice there. But it can be very strong. Perhaps you should stay out of it.



*edit: I have spent time in Beausoleil, but the harbor master was in Villefranche, just down the road. Same sun, though.

edit 2: Oh, you're back to no planes? Buh-bye, and good luck with your troubles.

[Heiwa]

Heiwa, I've spent time in Beausoleil. I stayed at the home of the harbor master for a few days.* The sun is indeed very nice there. But it can be very strong. Perhaps you should stay out of it.



*edit: I have spent time in Beausoleil, but the harbor master was in Villefranche, just down the road. Same sun, though.

edit 2: Oh, you're back to no planes? Buh-bye, and good luck with your troubles.

Well Mark, I visited your web site and looked at your video and noted that most people rated it and your ideas zero. So maybe you spent too much time in the sun? So look for that job as a camp guard.

[jhunter1163]

[QUOTE=beachnut;3328093]Sorry, that only happens in Europe, our concentration camps, like our torture are a joke. Camp Grenada is our only concentration camp and it was exposed years ago, when I was a kid.

Ah, Camp Granada. Those were the days...

For those who might not have been exposed to this...

http://en.wikipedia.org/wiki/Allan_Sherman

[twinstead]

Well Mark, I visited your web site and looked at your video and noted that most people rated it and your ideas zero. So maybe you spent too much time in the sun? So look for that job as a camp guard.

Fortunately, the number of idiots who post comments on sites like the one that host's gravy's video is meaningless. Frankly if you can't even convince US that you have a clue, how do you expect to convince somebody who can actually DO something about a new investigation or an indictment of the government you are SO sure is responsible for 911?

In other words, how many people who really know what they are talking about need to call your theory idiotic before you actually start questioning it yourself?

[bje]

No plane hit WTC1, so fire was started by other means.



Thanks for the additional quotation for your Little Red Book, Heiwa.

I rest my case.

[ElMondoHummus]

You better study my article again. I have added some links and ... BTW. No plane hit WTC1 and started the fire. Quite obvious, actually, even if not the topic of it. But it makes sense.

No plane hit WTC1, so fire was started by other means. One purpose was to knock out the cables to the television mast on the roof, so that local NY TV companies could not transmit the 'show' that followed. Only the five big ones, sharing the same control room, transmitted the 'show'. Hollywood live.

So if no plane hit WTC1 and only damage was externally due to - you know, I am sure that the core columns were not damaged at all.

And that explains the strange release of potential energy that followed, etc. according Nist.

There was no release of potential energy. Quite clear from the article, and we now know why.

Thanks for your assistance.

You can now apply for jobs as prison guards at the concentration camps being opened this summer all over USA.


Saying no plane hit WTC1 is contradicting reality. You must provide proof of this assertion that is more compelling than previous attempts on this forum (attempts which have failed miserably).

Mere joking about concentration camps is insufficient. Proof that the multitude of witnesses plus the video evidence is incorrect is necessary.

[bje]

You better study my article again...No plane hit WTC1 and started the fire. Quite obvious, actually,...

No plane hit WTC1, so fire was started by other means.


And your new revision states for all to see:

"The Towers also survived the initial impacts of planes on 911 due to their redundancy."

Another day, another story....

[A W Smith]

. BTW. No plane hit WTC1 and started the fire.
No plane hit WTC1, so fire was started by other means.
Thanks for stepping out of the closet and exposing your insanity for all to see. I think the world at large is done with you now. have fun. Hope this tidbit you shared doesn't sink your little boat business.
One purpose was to knock out the cables to the television mast on the roof, so that local NY TV companies could not transmit the 'show' that followed. Only the five big ones, sharing the same control room, transmitted the 'show'. Hollywood live.



I guess you are not aware that there are back up transmitters uptown on top of the Empire State Building, Perhaps you have heard of it? It was the tallest building in the world before the WTC towers were built.

[Heiwa]

Thanks for stepping out of the closet and exposing your insanity for all to see. I think the world at large is done with you now. have fun. Hope this tidbit you shared doesn't sink your little boat business.


I guess you are not aware that there are back up transmitters uptown on top of the Empire State Building, Perhaps you have heard of it? It was the tallest building in the world before the WTC towers were built.

All my facts are in my paper at http://heiwaco.tripod.com/nist.htm and particularly in the second part http://heiwaco.tripod.com/nist1.htm . No closet there!

Even if my paper is about the preposterous cause and effect proposed by Nist of the WTC1 collapse, it is of course of interest to look at the evidence of the events that lead up to that cause and the effect, e.g. the origin of the fire in WTC1. And it seems that there is only one video that captured that moment and according to the link in my paper that video is not genuine.

Or, it is quite good, but tampered with. But it shows that the fire didn't start only at the initiation zone but also much higher up ... just below the antenna.

So the WTC1 antenna didn't function and only five major networks followed what happened later. Apparently the ESB antenna didn't switch on for other networks to document the crime?

And if you study another link in my paper you find that those five major networks produced 'live' a lot of stuff that doesn't make any sense. So just study my paper and comment on that. Please.

My business is of course safety at sea (including their steel structures), but I can apparently learn a lot from safety in office towers and how poorly US authorities investigate those, particularly 911. Or vice versa, people interested in safety in office towers can learn from what happens at sea, where everything happens. Lots of pirates around that sink ships intentionally for various reasons ... and most of these pirates are actually sitting ashore in office towers. It's a small world.

So my business is doing well, thank you. It will never sink because it is based on good ground and on common sense.

Sometimes I wonder what many clowns on this thread are working to achieve. To become camp guards in gUSlag? That is quite insane!

[DGM]

All my facts are in my paper at http://heiwaco.tripod.com/nist.htm and particularly in the second part http://heiwaco.tripod.com/nist1.htm . No closet there!

Even if my paper is about the preposterous cause and effect proposed by Nist of the WTC1 collapse, it is of course of interest to look at the evidence of the events that lead up to that cause and the effect, e.g. the origin of the fire in WTC1. And it seems that there is only one video that captured that moment and according to the link in my paper that video is not genuine.

Or, it is quite good, but tampered with. But it shows that the fire didn't start only at the initiation zone but also much higher up ... just below the antenna.

So the WTC1 antenna didn't function and only five major networks followed what happened later. Apparently the ESB antenna didn't switch on for other networks to document the crime?

And if you study another link in my paper you find that those five major networks produced 'live' a lot of stuff that doesn't make any sense. So just study my paper and comment on that. Please.

My business is of course safety at sea (including their steel structures), but I can apparently learn a lot from safety in office towers and how poorly US authorities investigate those, particularly 911. Or vice versa, people interested in safety in office towers can learn from what happens at sea, where everything happens. Lots of pirates around that sink ships intentionally for various reasons ... and most of these pirates are actually sitting ashore in office towers. It's a small world.

So my business is doing well, thank you. It will never sink because it is based on good ground and on common sense.

Sometimes I wonder what many clowns on this thread are working to achieve. To become camp guards in gUSlag? That is quite insane!
Seek Help

[bje]

All my facts are in my paper at http://heiwaco.tripod.com/nist.htm

Yup, there it is, right on page 1, in your own words, Heiwa:

"The Towers also survived the initial impacts of planes on 911 due to their redundancy."


Amazing, isn't it?

[Heiwa]

Yup, there it is, right on page 1, in your own words, Heiwa:




Amazing, isn't it?

Model planes! Or similar. Use your imagination.

[Heiwa]

Seek Help

Don't need any. My facts are quite good. Maybe you need some help yourself? Too much television? Lack of sun? Drugs. Or just normal confusion?
A good medicin! Read my paper! Like thousand have. All cured.

[bje]

Model planes! Or similar. Use your imagination.

Don't need to use my imagination, Heiwa. Like you wrote, REAL planes hit WTC 1 and 2. (AA 11 and UA 175, to be precise)

[StoneRook]

Heiwa, you have stated several times you calculated various things.

Do you mind showing your work here?

Also, for some reason you now stating that "no planes" hit the building, yet you state that very thing in your paper.

Can you explain how numerous videos, photos, and people on the ground saw exactly what was transmitted by your "big five" networks?

I looked at your paper, and didn't see anything that has not been explained/debunked by others.

One thing that pops out is your "birdcage" analogy. You over simplified the towers construction, and I can't see where a birdcage, on fire, would respond like the towers did on that day.


BTW - the towers construction was not at all common. Buildings were not built like that.

so you can't compare what would happen to other buildings to what happened to the wtc. unless you take in account these differences - which you haven't shown.

[twinstead]

Don't need any. My facts are quite good. Maybe you need some help yourself? Too much television? Lack of sun? Drugs. Or just normal confusion?
A good medicin! Read my paper! Like thousand have. All cured.

Here's a hint: If you are crazy, you may not actually REALIZE it. The only clue you may get is pretty much everybody who knows what they are talking about tells you exactly that and even calmly shows you WHY.

All your responses to the people who are trying to bring a little reality into your world are exactly what somebody who needs help would say if they actually DID need help but didn't realize it.

It's okay. We understand.

[beachnut]

All my facts are in my paper at http://heiwaco.tripod.com/nist.htm and particularly in the second part http://heiwaco.tripod.com/nist1.htm . No closet there!

Sometimes I wonder what many clowns on this thread are working to achieve. To become camp guards in gUSlag? That is quite insane!
If you business was like your paper, you would be out of business. Sad to see, your ability to do well in business does not make you a rational person on 9/11 and other CT ideas.

Bad paper, good business. Who would guess?

[stateofgrace]

My business is of course safety at sea (including their steel structures), but I can apparently learn a lot from safety in office towers and how poorly US authorities investigate those, particularly 911. Or vice versa, people interested in safety in office towers can learn from what happens at sea, where everything happens. Lots of pirates around that sink ships intentionally for various reasons ... and most of these pirates are actually sitting ashore in office towers. It's a small world.

So my business is doing well, thank you. It will never sink because it is based on good ground and on common sense.


Really?

What steel structures are you responsible for offshore?

Winches? "A" Frames? Cranes? Tuggers? Maybe Vertical Lay systems? How about steel ropes or steel armoured cables?

Which steel structures do you actually work on offshore? I only ask because you never know one day you may actually come across somebody who really does work offshore,really does work on steel structures and has done so for the better part of thirteen years. You may actually come across somebody who has just spent the last four weeks sailing across the atlantic all the way from Nigeria in West Africa to Tampa Bay in the US, working on and maintaining steel structures on a real offshore vessel. You may come somebody who can ask you all sorts of questions about offshore safety and steel structures.

So just to establish a base to work with, which steel frame structures on offshore vessels do you work with? What exactly are your responsibilities for the said structures?

Oh yes and the question I asked you last time you were here and you failed to answer. You know the one that every single offshore worker would know the answer to.

" What is the exclusion zone? " Any idea yet my co offshore worker?

Sorry for the further derail ,but this thread is going nowhere anyway.

[Arus808]

"One of them is that a child is jumping in a bed ... and, instead of bouncing up and down, the bed is destroyed and the child falls down, down, down and the bed goes into thousand of pieces and the child dies. Many children get terrible dreams of such things. I tell them they do not happen in the real world. I tell them evil persons make up such bad things."

Really, you are telling children that jumping up and down on beds can't cause them to collapse? I'll be damned. I guess that scar on my head from when I was 11 isn't there.

So you are both a No Planer and a No Bed Side Tabler too?

What? he can't be serious/

I had to go to the hospital, and get 14 stitches, to sew up the large gash that split my temple to the middle of my head open, because I jumped up and down on a bed (despite my parents yelling to not do so), and the bed broke.

[Heiwa]

Heiwa, you have stated several times you calculated various things.

Do you mind showing your work here?

Also, for some reason you now stating that "no planes" hit the building, yet you state that very thing in your paper.

Can you explain how numerous videos, photos, and people on the ground saw exactly what was transmitted by your "big five" networks?

I looked at your paper, and didn't see anything that has not been explained/debunked by others.

One thing that pops out is your "birdcage" analogy. You over simplified the towers construction, and I can't see where a birdcage, on fire, would respond like the towers did on that day.


BTW - the towers construction was not at all common. Buildings were not built like that.

so you can't compare what would happen to other buildings to what happened to the wtc. unless you take in account these differences - which you haven't shown.

All the info is in the links in message #200. Shortly - the potential energy released due to buckling of columns in WTC1 at an unknown time does not exceed the strain energy of the structure below and the time for the latter event relative to the first is also not clear, which means that no global collapse can ensue. It is as simple as that. So I ask Nist to check their calculations and times.

[Heiwa]

Really?

What steel structures are you responsible for offshore?

Winches? "A" Frames? Cranes? Tuggers? Maybe Vertical Lay systems? How about steel ropes or steel armoured cables?

Which steel structures do you actually work on offshore? I only ask because you never know one day you may actually come across somebody who really does work offshore,really does work on steel structures and has done so for the better part of thirteen years. You may actually come across somebody who has just spent the last four weeks sailing across the atlantic all the way from Nigeria in West Africa to Tampa Bay in the US, working on and maintaining steel structures on a real offshore vessel. You may come somebody who can ask you all sorts of questions about offshore safety and steel structures.

So just to establish a base to work with, which steel frame structures on offshore vessels do you work with? What exactly are your responsibilities for the said structures?

Oh yes and the question I asked you last time you were here and you failed to answer. You know the one that every single offshore worker would know the answer to.

" What is the exclusion zone? " Any idea yet my co offshore worker?

Sorry for the further derail ,but this thread is going nowhere anyway.

Yes! OT of course. I just check that the relevant staff offshore properly inspects the steel structure as per the plan. This + training how to do it are often done on the spot offshore. We also do training ashore. Lot's of climbing around for close visual inspection, etc. Not so easy to find cracks, deformation and local corrosion, etc. And sometimes other vessels bump into the structure when they are in the exclusion zone. The structure of course stays in location all the time and does not sail around.

Vessels that sail around, e.g. to Tampa, are best inspected and maintained in port. No need to go offshore for that.

[gumboot]

My business is of course safety at sea (including their steel structures), but I can apparently learn a lot from safety in office towers and how poorly US authorities investigate those, particularly 911. Or vice versa, people interested in safety in office towers can learn from what happens at sea, where everything happens. Lots of pirates around that sink ships intentionally for various reasons ... and most of these pirates are actually sitting ashore in office towers. It's a small world.

You think office building workers are at risk from pirates?

KX61PUZ3xkI

iakR7sB0skw

You're right! :jaw-dropp

[stateofgrace]

Yes! OT of course. I just check that the relevant staff offshore properly inspects the steel structure as per the plan. This + training how to do it are often done on the spot offshore. We also do training ashore. Lot's of climbing around for close visual inspection, etc. Not so easy to find cracks, deformation and local corrosion, etc. And sometimes other vessels bump into the structure when they are in the exclusion zone. The structure of course stays in location all the time and does not sail around.

Vessels that sail around, e.g. to Tampa, are best inspected and maintained in port. No need to go offshore for that.

WTF???

What close visual inspections?

What plan do you work to ?

What on earth are you babbling on about ? Vessels bumb into one another inside the exclusion zone? You really have no idea do you ? You have absolutly no idea what the exclusion zone is do you ?

Again what steel structures are you responsible for offshore? It's a simple questions. I will give you a clue, it either oil rigs or offshore vessels, please pick one and tell me exactly what parts you are responsible for.

What do you do offshore that qualifies you so much to write a paper about the collpase of the WTC 's? I have worked with literally hundreds of offshore engineers, some good, some bad, but not one is qualified to write about the collpase of the WTC's like you claim you are.

So again what steel structures on offshore vessels do you work on?

Tell you what Heiwa maybe you could help us out here. We have a steel winch which has over 2000 metres of steel armoured cable on it, in fact it is sat less than twenty feet from me.It weights in at some 25 ton. What plan would you have in place for your staff to test it? How ofter is it tested? What certs would you issue after it had been tested and how long are they valid for? Exactly what inspections would you or you staff carry out on this armoured cable steel winch, static, dynamic or both ?

If you knew what you were talking about you would be able to shut me up and shoot me down in flames.

[Heiwa]

You think office building workers are at risk from pirates?


Yes, of course! Pirates, terrorists, perpetrators of crime = all same. But I work with safety ... not the newly developed business of security where Blackwater excels.

(High) safety = (high) probability of no accident based on scientific methods

Security = slobs in uniforms harrassing the public, koncentration camp guards, etc.

[Heiwa]

WTF???

What close visual inspections?

What plan do you work to ?

What on earth are you babbling on about ? Vessels bumb into one another inside the exclusion zone? You really have no idea do you ? You have absolutly no idea what the exclusion zone is do you ?

Again what steel structures are you responsible for offshore? It's a simple questions. I will give you a clue, it either oil rigs or offshore vessels, please pick one and tell me exactly what parts you are responsible for.

What do you do offshore that qualifies you so much to write a paper about the collpase of the WTC 's? I have worked with literally hundreds of offshore engineers, some good, some bad, but not one is qualified to write about the collpase of the WTC's like you claim you are.

So again what steel structures on offshore vessels do you work on?

Tell you what Heiwa maybe you could help us out here. We have a steel winch which has over 2000 metres of steel armoured cable on it, in fact it is sat less than twenty feet from me.It weights in at some 25 ton. What plan would you have in place for your staff to test it? How ofter is it tested? What certs would you issue after it had been tested and how long are they valid for? Exactly what inspections would you or you staff carry out on this armoured cable steel winch, static, dynamic or both ?

If you knew what you were talking about you would be able to shut me up and shoot me down in flames.

You really do not know what an offshore steel structure is! It is offshore (at sea away from land) and remains there during time of contract. It doesn't move. It may float or stand on the bottom. It is surrounded by en exclusion zone. It is not a seagoing vessel. And it is not a winch! A winch may be fixed on an offshore structure. Etc.

[stateofgrace]

You really do not know what an offshore steel structure is! It is offshore (at sea away from land) and remains there during time of contract. It doesn't move. It may float or stand on the bottom. It is surrounded by en exclusion zone. It is not a seagoing vessel. And it is not a winch! A winch may be fixed on an offshore structure. Etc.

So you are responsible for oil rigs, right?

What parts of the steel structure are you responsible for, specifically?

What do you do on oil rigs? What exactly is your responsibility for impending safety on these structure? What certs do you issue? What tests do you carry out?

Do you work on fixed, semi submersibles or jackups?

What do you do , exactly ?

Ps well done on the exclusion zone, finally found it on google did you?how big is it by the way ?What is excluded inside it? Why is it there?

[Norseman]

You really do not know what an offshore steel structure is! It is offshore (at sea away from land) and remains there during time of contract. It doesn't move. It may float or stand on the bottom. It is surrounded by en exclusion zone. It is not a seagoing vessel. And it is not a winch! A winch may be fixed on an offshore structure. Etc.

Heiwa, what happened to for instance:

Piper Alpha
Mumbai High North

[Heiwa]

So you are responsible for oil rigs, right?

What parts of the steel structure are you responsible for, specifically?

What do you do on oil rigs? What exactly is your responsibility for impending safety on these structure? What certs do you issue? What tests do you carry out?

Do you work on fixed, semi submersibles or jackups?

What do you do , exactly ?

Ps well done on the exclusion zone, finally found it on google did you?how big is it by the way ?What is excluded inside it? Why is it there?

You are a bit OT. Read my CV on my home page if you are interested.

[Heiwa]

Heiwa, what happened to for instance:

Piper Alpha
Mumbai High North


OT of course. Subject is WTC1 collapse. Comment on Urich's paper and my simpler one for children.

[CHF]

Oil rigs?

Looks like Heiwa is a Swedish version of Charles Pegelow.

[Heiwa]

Remember the columns will fail from axial impacts only, even with (3) - 90 degree plastic hinges.

Impacts? Please show me any evidence of an impact in WTC1 initiation zone (effect) ... and what caused it (release of potential energy above?, floors falling down?). And the times, please. Details, you know!

Three plastic hinges in an axially compressed column? You are joking! Why not one, two, four or five, etc?

I have seen some examples of only one plastic hinge in a column!! Due to an impact! The rest of the column evidently behaved elastically but deformed plastically, but only one real hinge (buckling), etc. But the impact was not axial - it was from the side (evidently).

Did they find any columns with three plastic hinges due to axial compression in the WTC1 rubble? It would be magic! I could use that info in my paper.

[stateofgrace]

You are a bit OT. Read my CV on my home page if you are interested.

I could not care less about your CV, it means zero. Anybody can add anything they like to CV's and this is now OT. It is the topic you brought up.

You said

My busness is safety at sea ( including there steel structures)I have asked you to clarify his statement. I have asked you simple questions about safety at sea. You have failed to answer. You have failed to address the very simple questions I have asked of you.

The exclusion zone is the 500 meter exclusion zone which is around all offshore platforms. It is the SAFETY zone.It is an industry standard and used around the globe. There are no naked uncontrolled flames allowed inside this zone, zero. There is no smoking outside allowed inside the 500 meter zone. It is there to prevent fires like Piper Alpha happening again.The only fire allowed is from the flare stack which is controlled at all time. It is a basic offshore safety rule, every single person who has ever set foot on an offshore installation or offshore vessel will know this. You are NOT allowed to work offshore if you do not know this and you will be sacked if you fail to stick to this very basic rule. Yet you who's busness is safety at sea failed to answer this most basic of questions , why is that ?

You then claimed you are responsible for steel super structures of offshore platforms. So why do you not know the very basic rules for the structures you claim to be responsible for?

What other basic offshore safety rules are you totally unaware of?

How about you explain the permit to work system or the TRA system, maybe the insolation system, please include in the toolbox talks you have with your staff.How about you tell me what safety certs you issue and how on earth you issue them after visual inspection of welds.

These are BASIC offshore safety systems and procedures that you must know about if you go anywhere near an offshore installation.

Well? What is wrong here? Will you shut me up and put me in my place ?

I personelly could not care less what you do for a living but when you claim to make a living by being involved with safety at sea, I get curious, because it affects me and the guys I work with.

So back up your claims and tell me what you do offshore and why you do not know the basic safety rules.

[bje]

Heiwa,

Have you ever once considered the implications of a ship when it sinks?

Even once in your entire career?

[Norseman]

OT of course. Subject is WTC1 collapse. Comment on Urich's paper and my simpler one for children.

The two oil rigs are just examples of the story fire weakening steel to the point of failure and collapse. Just like what happened in WTC 1 and 2:

Piper Alpha (http://home.versatel.nl/the_sims/rig/pipera.htm)
Mumbai High North
(http://home.versatel.nl/the_sims/rig/mhn.htm) and here (http://www.mace.manchester.ac.uk/project/research/structures/strucfire/CaseStudy/HistoricFires/Other/default.htm).

Links for the interested reader.

[A W Smith]

Anders your business web site is hosted on a tripod page. There is no list of clients I can find there, And I can find no listing of your business on various maritime association web sites or directories, Anders,, What maritime associations do you belong to?????

[Heiwa]

I could not care less about your CV, it means zero. Anybody can add anything they like to CV's and this is now OT. It is the topic you brought up.



?? Nothing wrong with my CV - it is on my web site. There are also papers I have read at various shipping and offshore conferences and some books about safety at sea, etc. And also details of the only oil tanker design approved by United Nations International Maritime Organisation as better than double hull. It is my design of course. I attended many IMO conferences about that. You can read about its steel structure also.

I have actually a very good reputation in the shipping industry, so I do not have to publish lists of clients, etc. Let the facts tell the truth.

I use the same principles when I analyse the WTC1 collapse.

[funk de fino]

You really do not know what an offshore steel structure is! It is offshore (at sea away from land) and remains there during time of contract. It doesn't move. It may float or stand on the bottom. It is surrounded by en exclusion zone. It is not a seagoing vessel. And it is not a winch! A winch may be fixed on an offshore structure. Etc.

A jack up is a sea going vessel, it has bulkheads and is built to maritime standards. It moves around the field during contracts. Semi subs also move on contract. There are also drill ships in the North Sea.

Exactly what are you claiming to be responsible for? Do you actually go offshore?

[Heiwa]

A jack up is a sea going vessel, it has bulkheads and is built to maritime standards. It moves around the field during contracts. Semi subs also move on contract. There are also drill ships in the North Sea.

Exactly what are you claiming to be responsible for? Do you actually go offshore?

Exactly - jack ups, drilling vessels and semi-subs are seagoing vessels that are always surveyed and repaired ashore at a shipyard in a drydock when they are clean and gas free. Easy! Nothing to do with offshore structures that remain in position in the middle of the ocean for years, not clean, not gas free at any time without the possibility to be inspected in peace and quiet ashore.

So you have to do it offshore. Quite a challenge. If you don't do it properly you have accidents like the ones mentioned above.

Study my web site and you will find out what offshore structures I specialise in and what systems I have proposed to make the job safer!

BTW - did you find any errors in my article about the WTC1 collapse?

[WildCat]

BTW - did you find any errors in my article about the WTC1 collapse?
Besides the claims that no planes hit the towers and that steel gets stronger as it is heated? :rolleyes:

[funk de fino]

Exactly - jack ups, drilling vessels and semi-subs are seagoing vessels that are always surveyed and repaired ashore at a shipyard in a drydock when they are clean and gas free. Easy! Nothing to do with offshore structures that remain in position in the middle of the ocean for years, not clean, not gas free at any time without the possibility to be inspected in peace and quiet ashore.

So you have to do it offshore. Quite a challenge. If you don't do it properly you have accidents like the ones mentioned above.

Study my web site and you will find out what offshore structures I specialise in and what systems I have proposed to make the job safer!

BTW - did you find any errors in my article about the WTC1 collapse?

You never answered. Do you actually go offshore to fixed oil platforms in the North Sea? If so which platforms have you been to?

I found errors in your paper. Not wanting to be disrespectful, but as your paper is disrespectful, I found it to be junk.

[bje]

Let the facts tell the truth.


Indeed, they do.

[GregoryUrich]

You never answered. Do you actually go offshore to fixed oil platforms in the North Sea? If so which platforms have you been to?

I found errors in your paper. Not wanting to be disrespectful, but as your paper is disrespectful, I found it to be junk.

This thread is not about Heiwa's competence or his paper. Please stay on topic and/or start a new thread.

Some have suggested that yield strength should be used instead of ultimate strength. I provide the following citation regarding yield strength and the portion of the stress-strain curve between yield and ultimate strength from Wikipedia:

In structural engineering, this is a soft failure mode which does not normally cause catastrophic failure unless it accelerates buckling.

Correct me if I'm wrong, but I think most engineering books will be in agreement. I have seen elsewhere that the length of one floor is too short for buckling to be the failure mode so "unless it accelerates buckling" shouldn't be an issue.

Thus, I still think it is correct to use the ultimate strength in the calculation.

[funk de fino]

This thread is not about Heiwa's competence or his paper. Please stay on topic and/or start a new thread..

I think you will find I have told heiwa to stop derailing this thread, that I thought was a promising one. I also told him he should apologise to you for spoiling this thread with his junk claims.

[Dave Rogers]

This thread is not about Heiwa's competence or his paper. Please stay on topic and/or start a new thread.

Ironically enough, Heiwa said much the same thing about us discussing your analysis in this thread, back around post #100.

Some have suggested that yield strength should be used instead of ultimate strength.

Personally, I think your choice of ultimate strength is appropriate if you're trying to test whether it's inevitable that collapse would have propagated, and hence is consistent with the highly conservative assumptions in the Bazant model. If you're trying to disprove collapse propagation you'd need a much more complex model, and for a convincing disproof I'd want to see that the yield strength wasn't exceeded, because there's such clear evidence that the initial failure was buckling of the perimeter columns due to pull-in.

Dave

[Heiwa]

This thread is not about Heiwa's competence or his paper. Please stay on topic and/or start a new thread.

Some have suggested that yield strength should be used instead of ultimate strength. I provide the following citation regarding yield strength and the portion of the stress-strain curve between yield and ultimate strength from Wikipedia:



Correct me if I'm wrong, but I think most engineering books will be in agreement. I have seen elsewhere that the length of one floor is too short for buckling to be the failure mode so "unless it accelerates buckling" shouldn't be an issue.

Thus, I still think it is correct to use the ultimate strength in the calculation.

First I noted a minor error in the table para. 6 of your paper. Unit for Ultimate strength is N/m² (=Pa and not Pa/m²).

If the theoretical compressive buckling stress for a column exceeds the yield stress, evidently the column will yield before it buckles, i.e. there will be out of plane bending and plastic deformation in the highest stressed fibers, but we still do not know when buckling=collapse occurs. The column section changes - it can collapse or it can re-arrange itself to a more stable configuration. However, instinctively the critical stress is less than the ultitmate strength (or stress) unless the column section itself (its geometry) is extremely solid. Compare a tube pipe with a certain wall thickness with a solid round steel bar. So the answer may be that the critical stress in this case is somewhere between yield and ultimate stress? And it depends on the column section.

Furthermore - this critical stress in the substructure is only experienced when (during) the original (energy) impact occurs. As soon as the impact has passed, we are back to a static condition again in the area under consideration, e.g. just below the initiation zone/impact area.

It could very well be that some columns - or rather some extreme fibers in the columns - are stressed above yield during the impact and either cause the complete column to buckle/collapse or, also possible, the column reconfigure its cross area to withstand buckling/collapse and re-directs the impact energy elsewhere.

The latter effect is easiest understood when watching somebody hitting a nail with a hammer. You may actually knock apart the nail if you try to hit it through a stiff support, e.g. a steel plate - the nail goes into two pieces - or the nail bends and the hammer (the impact energy) slips off the nail head and hits something else. And so on.

Neither Bazant nor NIST understands this.

[Heiwa]

Some maybe Off Topic comments to above (they are Off Shore :-)

Once there was an offshore structure with a big crane fitted on it. For various reasons, including incompetense, the crane suddenly collapsed and fell down and impacted the offshore steel structure below. Luckily the offshore structure acted like a spring and the crane bounced off and disappeared into the water beside the offshore unit. Goodbye crane.

What were the damages to the offshore structure? Well, it was a big buckle in the steel main deck below the crane = the plate was plastically deformed down a fair distance and the stiffeners below were also plastically bent and ... they had fractured in their highest stressed fibers.

Note that they crane didn't punch a hole through the offshore structure and caused global collapse or sinking or whatever! The potential energy of the crane (mass above) simply didn't exceed the strain energy of the structure below.

Your obedient servant later sorted out the matter at minimum cost and highest safety. Obviously the (ir)responsible parties prefer to be anonymous.

[uk_dave]

Your obedient servant later sorted out the matter at minimum cost and highest safety. Obviously the (ir)responsible parties prefer to be anonymous.

But of course.

I remember one time when I was in the SAS and carrying out Royal protection duties........

..... ahhhh but I can't really talk about that.

[GregoryUrich]

Ironically enough, Heiwa said much the same thing about us discussing your analysis in this thread, back around post #100.

Personally, I think your choice of ultimate strength is appropriate if you're trying to test whether it's inevitable that collapse would have propagated, and hence is consistent with the highly conservative assumptions in the Bazant model. If you're trying to disprove collapse propagation you'd need a much more complex model, and for a convincing disproof I'd want to see that the yield strength wasn't exceeded, because there's such clear evidence that the initial failure was buckling of the perimeter columns due to pull-in.

Dave

I think it was Heiwa's comment that got me thinking about it. Anyway, I've recalculated the stiffness C (still based on the entire lower structure) using:

1/Keff = 1/K1 + 1/K2 + ... + 1/Kn

and I get 6.40 x 10^9 GN/m. I did the same for the top part and got 11.9 GN/m. I was surprised that the top was almost 2x stiffer.

ETA: I agree, disproving collapse propagation would require a more complex model that B & Z's. My point is that the B & Z's model may not prove collapse propagation. I'm working out some new numbers to see if the deflection of the top floor excedes the offset yield point (0.2%). If not, those columns never reach the elastic limit.

[Newtons Bit]

I think it was Heiwa's comment that got me thinking about it. Anyway, I've recalculated the stiffness C (still based on the entire lower structure) using:

1/Keff = 1/K1 + 1/K2 + ... + 1/Kn

and I get 6.40 x 10^9 GN/m. I did the same for the top part and got 11.9 GN/m. I was surprised that the top was almost 2x stiffer.

It's much shorter =]

Are you planning on posting an updated version of your paper?

edit: are you planning on using the entire lower block or will you use x number of stories based on the elastic wave speed?

[Major_Tom]

Dave notes;

because there's such clear evidence that the initial failure was buckling of the perimeter columns due to pull-in.


The perimeter pulling in was witnessed on only the east face of the South Tower.

There is no mention of pulling in for the North Tower perimeter or for the other 3 faces of the South Tower.

The inward pull is seen only along the 81st (?) floor.


There is no evidence for inward pulling anywhere else.


A chief characteristic of the perimeter of all 8 faces is an OUTWARD PEELING during the "collapse".


This can be seen clearly in the rubble distribution. Most all the perimeter pre-fab sections are seen OUTSIDE the footprints of the towers.


Dave, do you have any other evidence of inward pull of the perimeter besides that mentioned above?

[GregoryUrich]

It's much shorter =]

Are you planning on posting an updated version of your paper?

edit: are you planning on using the entire lower block or will you use x number of stories based on the elastic wave speed?

I'll try to do it based on elastic wave speed if that's kosher. I'm not quite sure how to calculate the time though, because it's based on the max deflection/avg velocity for the deflection period which changes if I adjust the stiffness for fewer floors.

[einsteen]

If you are spring thinking then the energy is the integral of force over distance, i.e. Int (kx)dx=(1/2)kx^2 . I'm no engineer but to me it looks like it is mainly the distance that determines how much energy can be absorbed. If you are at the maximum distance of elasticy then the amount of energy is only a little bit. If the top section is elastically 'absorbed' then the maximum x is a relevant value. But if it isn't then there is the plastic phase. I've seen a couple of those stress strain diagrams and to me it looks like the latter phase is able to absorb much more energy than the elastic phase for the simple reason that the area under the graph is much bigger. If you want to prove that a top section is absorbed then that phase is also relevant.

Major_Tom

The perimeter pulling is an interesting and hot topic. The last I've seen about it was a posting by a debunker called "Gravy" he posted two pictures, on the first you see more or less intact columns and on the second one a failed column. The time stamp was however the same, this implies that it was a very fast process.

[Newtons Bit]

I'll try to do it based on elastic wave speed if that's kosher. I'm not quite sure how to calculate the time though, because it's based on the max deflection/avg velocity for the deflection period which changes if I adjust the stiffness for fewer floors.

It can be very iterative. You have to know the right answer to one question before getting the second, but the first question involves the second answer. Welcome to engineering :D

You could assume that the upper block deaccelerates from full velocity to zero velocity (i.e. just barely or not overcoming the lower block) to be conseravtive in favor of collapse prevention without being absurd.

[Norseman]

The perimeter pulling in was witnessed on only the east face of the South Tower.

There is no mention of pulling in for the North Tower perimeter or for the other 3 faces of the South Tower.

The inward pull is seen only along the 81st (?) floor.

There is no evidence for inward pulling anywhere else.

Major_Tom I suggest that you take a careful look at NIST NCSTAR 1-6 to get a understanding of the collapse initiation as described by NIST. Search for the word bowing. Even on your website you have a picture (http://www.sharpprintinginc.com/911/index.php?module=photoalbum&PHPWS_Album_id=25&PHPWS_Photo_op=view&PHPWS_Photo_id=800) showing inward bowing on the south face of WTC 1. That picture comes from the NIST reports (Figure 8-106 NIST NCSTAR 1-5A). Are you really sure you are being honest with us now.


A chief characteristic of the perimeter of all 8 faces is an OUTWARD PEELING during the "collapse".

This can be seen clearly in the rubble distribution. Most all the perimeter pre-fab sections are seen OUTSIDE the footprints of the towers.


Yes that is entirely correct. When the upper block of both towers fell they where funneled inside the lower block splitting it open in the process. This is very evident in the videos. It was columns against floors inside the towers, a match the floors never had any chance of winning whatsoever. The exterior columns where pushed out by the falling mass inside the Tower. The load bearing strength of the exterior columns and the interior columns did not matter after the collapse initiation. They could not stand on their own without the support of the floors inside the towers. No need for the totally unsubstantiated thing your website is all about, but that you have been hinting at in your posts all the time.

[einsteen]

The exterior columns where pushed out by the falling mass inside the Tower. The load bearing strength of the exterior columns and the interior columns did not matter after the collapse initiation. They could not stand on their own without the support of the floors inside the towers. No need for the totally unsubstantiated thing your website is all about, but that you have been hinting at in your posts all the time.
I'm wondering what makes you think that, if this is true, they were standing on their own ? That massive top section was still connected, perimeter columns, trusses, floors, core columns.

Maybe this helps a little bit for you

http://i3.tinypic.com/7wj2zxc.jpg

http://i3.tinypic.com/7wj2zxc.jpg

[Norseman]

I'm wondering what makes you think that, if this is true, they were standing on their own ? That massive top section was still connected, perimeter columns, trusses, floors, core columns.

Maybe this helps a little bit for you

http://i3.tinypic.com/7wj2zxc.jpg

http://i3.tinypic.com/7wj2zxc.jpg
When the collapse initiated all the columns in the initiation area became overloaded, they buckled up and broke off. From then on it was floor against columns inside the tower when the upper block destroyed the floors on its way dawn to the ground. Without the horizontal support of the floor structure the columns could not stand, they would buckle up and collapse. Do I need to remained you of what happened to the remaining core columns that were still standing after the rest of the towers had collapsed?

So even though the columns in the lower part had not been weakened by fire, as the columns in the initiation area, it did not matter.

[beachnut]

If you are spring thinking then the energy is the integral of force over distance, i.e. Int (kx)dx=(1/2)kx^2 . I'm no engineer but to me it looks like it is mainly the distance that determines how much energy can be absorbed. If you are at the maximum distance of elasticy then the amount of energy is only a little bit. If the top section is elastically 'absorbed' then the maximum x is a relevant value. But if it isn't then there is the plastic phase. I've seen a couple of those stress strain diagrams and to me it looks like the latter phase is able to absorb much more energy than the elastic phase for the simple reason that the area under the graph is much bigger. If you want to prove that a top section is absorbed then that phase is also relevant.

Major_Tom

The perimeter pulling is an interesting and hot topic. The last I've seen about it was a posting by a debunker called "Gravy" he posted two pictures, on the first you see more or less intact columns and on the second one a failed column. The time stamp was however the same, this implies that it was a very fast process.
http://forums.randi.org/imagehosting/879045fd54c927534.jpg
The time is in minutes! This sequence is just as the failure begins. Seconds apart! One minute resolution on time stamp! This is not a test, this is a standard logic, you must have the ability to catch the easy non errors or you are lost! Please stop making simple errors. Your time stamp ideas is a false idea.

Have you even wonders why 9/11 truth can not connect the dots! This is an example. Failure to understand evidence. Both photos are in the same minute! Is this possible, there are 60 seconds in the Minute. Time is relative or something. What did Einstein say?.

[einsteen]

But in the videos I've seen it is a very fast process.

[beachnut]

But in the videos I've seen it is a very fast process.
Fast is MACH 3, the fastest speeds on 9/11 were the objects hitting the ground first, 200 plus mph. The fall of the WTC started with slight bowing, and took a long time, not fast; it is gravity. It was not a fast process it was a large mass falling event. BTW, while the truther engineers and truther want to be engineers tear up the paper, they will never understand the WTC was a floor failure event, as they fail to even model that which they really need to study. Have you noticed not a single truther engineer or want to be, has sated the weight need to fail just one floor of the WTC?

Therefore after they think they have destroyed a simple model of collapse, they will be void of truth and failed to attack the real problem. Did they missed the full scale model of the WTC hit by planes, burning, and failing?

Not fast, just like you fall off your roof, it may seem fast but you started at zero.

[Major_Tom]

Beachnut,

As I mentioned, there was only inward belding along one horizontal line along one face of one tower observed.


And as if to refute me, you show the very facade I mentioned.


Each building has 4 sides, so that leaves 7 facades on which inward buckling was not observed.



However, outward peeling during the "collapses" was observed from all sides of each building.


Beachnut writes:

The fall of the WTC started with slight bowing, and took a long time, not fast; it is gravity.

Which "WTC"? Which facade?


You have one line of bending on one facade and you want to make a general theory of it?

[beachnut]

Beachnut,
As I mentioned, there was only inward belding along one horizontal line along one face of one tower observed.
And as if to refute me, you show the very facade I mentioned.
Each building has 4 sides, so that leaves 7 facades on which inward buckling was not observed.
However, outward peeling during the "collapses" was observed from all sides of each building.
Beachnut writes:
Which "WTC"? Which facade?
You have one line of bending on one facade and you want to make a general theory of it?
You are not reading! That post was for someone else, not you! Do you have problems understanding things? Your ideas are so far out, there is not need to debunk you; you do it yourself. Look at your collection of photos proving a gravity collapse, no thermite, no blast effects. Just impact, fire, and collapse did all the damage you see. You fail to even calculate the energy of a falling WTC! How can you make any conclusions?

Sorry, you were debunked the moment you said hello, albeit with the word "test"! And of course your first post of false information reference the false work of Max Photo. Oops!

[Gravy]

Major Tom, that you call yourself a collector of photographs, yet you're not aware of the photographs and videos that show inward bowing of exterior columns on both towers, is...

expected.

Why are you here? What benefit do you derive from wasting intelligent peoples' time?

[Gravy]

The perimeter pulling is an interesting and hot topic. The last I've seen about it was a posting by a debunker called "Gravy" he posted two pictures, on the first you see more or less intact columns and on the second one a failed column. The time stamp was however the same, this implies that it was a very fast process.You're another one who's been "investigating" for a long time, but you're not aware of the photos that show the inward bowing long before the collapses? That's...

expected.

So why are you here, einsteen? What benefit do you derive from choosing to remain ignorant?

[beachnut]

Beachnut,
As I mentioned, there was only inward belding along one horizontal line along one face of one tower observed.
And as if to refute me, you show the very facade I mentioned.
Each building has 4 sides, so that leaves 7 facades on which inward buckling was not observed.
However, outward peeling during the "collapses" was observed from all sides of each building.
Which "WTC"? Which facade?
You have one line of bending on one facade and you want to make a general theory of it?
WTC2 - a sequence before the tower fell! WTC2 - I repeat, WTC2, as in TWO too. Oops, you did not read NIST http://wtc.nist.gov/NISTNCSTAR1-5A_chap_9-AppxC.pdf

http://forums.randi.org/imagehosting/879045fd54c927534.jpg
WTC2 bowing!

Next we have WTC1, as in ONE also. WTC1 the other tower of the twins.
http://www.beachymon.com/photo/wtc1bowingpost.jpg
WTC1 bowing! WTC1

Now you have two tower, both bowing before collapse! You failed to do your home work! See http://wtc.nist.gov/WTC_Conf_Sep13-15/session6/6McAllister.pdf for more information! Not that you need it mister radio controlled bombs.

As you have been wrong before, so you are again.

Yes, the buildings were twins! Is this why you fail to understand both had bowing?

I see your refute you and your website, and raise the fact you refute yourself and now refuted you post of a post not to you.

[Major_Tom]

You got me.

Now you have 2 of 8 facades on which bowing was observed.

That means that 3 of the 4 facades of each tower had no inward buckling observed.

[AZCat]

You got me.

Now you have 2 of 8 facades on which bowing was observed.

That means that 3 of the 4 facades of each tower had no inward buckling observed.

Yes. Do you find that insufficient? Do you think all four sides of the building had to fail in order to cause collapse?

[DGM]

Yes. Do you find that insufficient? Do you think all four sides of the building had to fail in order to cause collapse?
The big honking hole from the plane doesn't count.:rolleyes: