Why a one-way Crush down is not possible

[Heiwa]

Anders,


.
Look, you ignorant, pompous, rude jerk.

You are DAMNED right that you do not know what I am saying.

I INVITED you into a discussion with me for the precise purpose of explaining to you what I am saying. You RUDELY ignored all of my attempts to discuss the issues.

So please refrain from your typically fumbling, incompetent attempt to interpret what I have said until after you have cleared them with me.

Your interpretation here is 100% wrong.

I guess ignorance is bliss, eh, Anders.

LOL.

Tom

Well, you say that 13 floors (#98-110) abt 4 m apart in a 53 m high assembly of floors drop and hit one floor, #97.

But floor #110 is 53 m away from floor #97! The only floor that floor #110 can contact is floor#109, but for that to happen you have to remove all columns between floors #109-110.

So, let's agree that it is an assembly of floors (#98-110), part C, that is alleged to contact floor #97 that happens to be part of another assembly of floors (#1-97), part A, i.e. part C contacts part A (as suggested by Bazant).

Bazant suggests further that part C is rigid (uniform density, it will not deform, it is indestructible at this time) but it is nonsense. And therefore Bazant's model is nonsense.

Now, you suggest that an assembly of floors, upper part C, is capable to one-way crush down lower part A, floor by floor, i.e. 97 impacts take place.

My opinion is clear! Your suggestion is impossible! Actually a ridiculous suggestion. Because at impact C on A, local failures will occur in both C and A. The weak elements or weak connections in both C and A adjacent to the impact interface fail first. Energy is absorbed as local failures. A jolt (decelaration - unit m/s²) of C should be observed. Then damaged elements will displace and contact other elements. Friction develops. More energy is now absorbed as friction. Etc, etc. And after a while of more local failures/friction the destruction is arrested. Happens every time you drop a part C of a structure A on the rest of A. It should take less than ONE second in the WTC 1 case.

This is the reason Why a one-way Crush down is not possible = topic = post #1.

Anyone suggesting that part C structure can one-way crush down part A structure is complicit to mass murder! Let's expand the thread to include that suggestion.

 

[Justin39640]

FW,

You have to consider the PATHWAY that the forces (i.e., from weight & momentum) take in order to be transmitted from one component to another. These forces have to be transmitted thru physically touching components.

Heiwa is right that the upper floors do not transmit their weight & momentum DIRECTLY. Since they are not DIRECTLY touching floor 97. But the upper floors DO connect to the support columns and the support columns DO impact on Floor 97. So, ALL of the upper floors DO transmit both their weight & momentum to Floor 97 THRU the support columns. Actually thru approximately 1/2 the core & external columns.

Heiwa is right that the lower column stubs will also impact on the underside of floor 98. This is a version of the hunter with a spear, allowing the lion to charge him, burying the back end of the spear in the ground, and allowing the lion's momentum to impale itself on the end of the spear. (My hat's off to ANYONE who has ever pulled off this stunt...)

So there WILL be a mutual destruction of both Floors 97 & 98.

But after that first floor's destruction, the picture changes.

As I tried to explain here: http://www.internationalskeptics.com/forums/showthread.php?postid=4743226 , there are some subtle effects that cause the destruction to not be symmetric, up vs. down. This symmetic destruction is the core of Heiwa's (incorrect) contention.

There are two components that are responsible for the destruction of the floors: the column stubs and the mass of the debris that has been broken free in the crush zone. The column stubs are only significant during the 97th & 98th floor's destruction. After that, lateral forces simply sweep the column stubs aside.

The descending mass is all that matters. And as I tried to show, that mass of debris will collect at the bottom of the descending (& growing) upper body. And it will interleaf and connect to the upper blocks columns. And therefore that layer of debris will transmit the weight of the entire upper block (by virtue of its connection to the columns) and protect the upper block from further destruction.

As I tried to explain in that post, by the time the crush zone reaches any given floor, that floor has ALREADY had 2/3rds of it supports ripped apart. With this level of destruction, it has already been turned for the most part into loosely connected debris. Much of it already falling.

A piece of free falling debris, descending at 10 mph, puts far, far less impact on the 50 mph descending mass than that same piece of debris would have if it had been stationary & firmly fixed to its supports. This is a large part of the reason for the asymmetric destruction.

So, to answer your question, the placement of lawn chairs & lead plates is, of course, irrelevant to the ultimate fate of the universe.

You have been GROSSLY unfair to Heiwa, FW. You've expected him to discuss the issues with honesty and maturity.

How COULD you...?

Tom

when i read tony's and heiwa's ideas it really stumps me
these people are engineers and in comparison much smarter than me
but
that might be their downfall
superiority complex maybe?
although many many more people who are smarter than i agree with my thoughts (or have shown where i was wrong in my thinking and i corrected myself) these people also are quick to point out where their thinking may be wrong and correct themselves
the CT's engineers dont seem to have that ability

as engineers they also (like you just pointed out..again lol) they assume the collapses were symmetrical or they talk about the 2 parts as if they were solid masses
where in reality the collapses were anything but symmetrical
and the 2 masses were anything but solid
they were made of millions of tiny pieces
and every single tiny part failure counts
at the start of collapse in my mind i can visualize bolts, rivets, and small plates shearing which in turn leads to larger parts failure and part groups failure randomly as loads are displaced
ultimately leading to global collapse

maybe this is from my practical experience rather than pen and paper

working with what engineers put out there
sometimes us guys in the field scratch our heads and say "wtf were they thinking?" after the uber failure is evident in real world scenarios

if engineers were never wrong
the word "recall" wouldnt exist lol (at least not in that context)

 

[GlennB]

when i read tony's and heiwa's ideas it really stumps me
these people are engineers and in comparison much smarter than me
but
that might be their downfall
superiority complex maybe? ....

Yes. There are nutcases in every single human field of endeavour.

 

[newton3376]

A doofus you are. Explained it, already Tony has.

It goes like this -
The building was carefully CD'd just as collapse initiated. The lack of 'jolt' proves this. Thus, the upper block expended no kinetic energy in breaking the lower block as the latter was already falling. The fact that upper block fell at well less than g acceleration means that .. er... well, it just means SOMETHING OK ????

It's all so clear now.....

Maybe he'll write a 'paper' about it, you Bush-loving shill-sheeple.

His 'paper" should be used in an intro ME undergrad course as an example of how 'not' to perform proper engineering analysis....

I'm afraid I have some bad news for you, Mr newton3376 ......

Scary.......

 

[bill smith]

Yes, bill. I know EXACTLY where the 3/4th of a square mile of mesh reinforcing has gone. It has gone nowhere.

This whole charade is nothing but you, publicly fondling yourself. It's gotten the rest of us rather uncomfortable, frankly.

BTW, engineers DO design toasters. Anyone, engineer or not, that has actually designed anything & brought it to market knows 10,000x more than you do about ALL of these subjects.

Have a little respect for toaster designers.

Last note. To show you (what everyone else but you understands) what a techno-buffoon you are ...

You said that there was "some" mesh there. But too little "by dozens of orders of magnitude". Which is exactly what I commented on that prompted your strutting reply.

Let's assume that there is just ONE FOOT of your mesh visible.

ONE dozen "orders of magnitude" would mean 10¹² feet of mesh. This is sufficient mesh to reach from the earth to the moon and back. About 4000 TIMES.

TWO dozen orders of magnitude would be 10²⁴ feet.
This is enough to reach the nearest star Proxima Centuri, and back.
About 8 million times.

Still think you are missing "dozens of orders of magitude", dummy?

Do you even have enough understanding to be embarrassed by your silly attempt at technobabble?

Just curious.

Tom

Yes I'm awfully awfully embarrassed. But never mind is what I say. See- I told you it was a lot of mesh that's missing from the rubble. The best part of a square mile in fact. I notice you didn't have any sensible answers to the question either. What about the '' Find the missing square mile of rebar '' Challenge.
Do the sexual references get your rocks off then ? I was always uneasy about you following me around. A groupie is one thing but....

 

[Grizzly Bear]

The write up you link to is a bogus example. Had the five pennies been dropped into the empty jar on the paper they would not have caused the paper to fail. While there would be an amplified load, there is also something not being explained that is allowing the seeming failure with far less weight, and that is that the shear area of the paper was much smaller when the pennies were dropped by themselves, so the stress on the paper was much higher, more for that reason than the dynamic load. The five dropped pennies are not applying more load than the jar full of pennies at all.

I don't think the pennies experiment was ever intended in that paper to directly model the behavior of the towers. It was solely intended to demonstrate to an average reader the difference between a dynamic and a static load. I've used some of my old structures notes in a similar fashion to demonstrate the difference in the load capacity of a simple column with different values in it's longest unbraced span. I do think he should have focused on the smaller scale part of that experiment though since it would have related more to what was happening inside the towers -- in that the loads weren't being uniformly distributed across the floors.That's an understanding you start out with when you examine that experiment in the first place.

From what you say you are an engineering student. What discipline? If you are mechanical or civil you should have figured this out, if you have already had strength of materials and stress analysis courses.

The undergraduate Architecture core curriculum at my university requires classes in methods and materials (two classes), and structures (I & II). The former discusses how materials are used in construction, as well as their various applications, and properties. Structures teaches students foundation material for calculating loads on simple beam and column assemblies. This also involves drawing force, and moment diagrams of the loads on these assemblies.

You are right that the collapse of the towers would have required something like an 8g amplification of the upper block's load. How much would the upper block have to decelerate in feet or meters/second/second to apply an 8g amplification of it's load? If the velocity loss needed to supply the kinetc energy for deforming and buckling the columns on either side of the collision is approximately 17 feet/second what would be the duration of the impulse?

When I did the original calculation I assumed a scenario in which the entire mass came to a complete stop within 3 feet after accelerating for a single floor height. In other words the working assumption in that calculation was that the floor depth could bring the mass to a complete stop. Off the top of my head that was ~ 81-84 m/s² in the negative relative to the direction of gravity.

My assumption ignores the realistic strength of the floors and the non-uniform nature of the load, which would require more complex calculations to deal with .

 

[Newtons Bit]

Yes I'm awfully awfully embarrassed. But never mind is what I say. See- I told you it was a lot of mesh that's missing from the rubble. The best part of a square mile in fact. I notice you didn't have any sensible answers to the question either. What about the '' Find the missing square mile of rebar '' Challenge.
Do the sexual references get your rocks off then ? I was always uneasy about you following me around. A groupie is one thing but....

The mesh is still in the concrete. You shouldn't be able to see much in the way of wire mesh laying around by itself.

Unless all the concrete was dustified! zomg inside job?!?

 

[bill smith]

The mesh is still in the concrete. You shouldn't be able to see much in the way of wire mesh laying around by itself.

Unless all the concrete was dustified! zomg inside job?!?

We are talking about the equivalent of a one-acre homogenous block of concrete 30 feet thick. When you break a block like that into the small pieces that we typically see in the rubble you may realise just how much cincrete r missing from the rubble. That can maybe be explained by the pulverisation we saw but the missing three quarters of a mile of wire mesh reinforcing cannot be explained in this way. ..and in my opinion neither can the 5,000 missing floorpans or the thousands of tons of missing core columns.

 

[phunk]

We are talking about the equivalent of a one-acre homogenous block of concrete 30 feet thick.

Not quite, rather than a 30 foot thick block, it was 100 or so sheets a couple inches thick. Much easier to shatter into small pieces.

When you break a block like that into the small pieces that we typically see in the rubble you may realise just how much cincrete r missing from the rubble.

How much was missing? Give us an estimate.

That can maybe be explained by the pulverisation we saw but the missing three quarters of a mile of wire mesh reinforcing cannot be explained in this way. ..and in my opinion neither can the 5,000 missing floorpans or the thousands of tons of missing core columns.

How can you tell how much is inside the pile? What was the volume of the pile, and what should it have been?

 

[Gamolon]

Not without a jolt(s) and a velocity loss. There are none.

Are you telling us that the floor truss connections on the perimeter columns were enough to create a "jolt" and a "loss in velocity" to the falling upper mass of the tower?

If not the floor truss connections, can you please explain to me what was supposed to cause this "jolt" and "loss in velocity"? What structural members?

 

[newton3376]

Anyone suggesting that part C structure can one-way crush down part A structure is complicit to mass murder! Let's expand the thread to include that suggestion.

Agreeing with you is complicit to mass stupidity.....

Let's expand the thread to include that suggestion....

 

[Gamolon]

The jolt required is that necessary to overcome the reserve strength of the columns below, which were capable of supporting several times the load of the entire upper block above them.

Ok. Someone PLEASE explain this to me as I seem to be missing some major point here.

Why are the columns being used as the reason there should be a "jolt" or "loss in velocity"? If the columns were that strong, wouldn't it be the floor truss connections that would be subject to the load of the upper falling mass?

I mean the perimeter AND core columns were outside the perimeter of the concrete floors.

The upper mass, in what I envision, didn't come down on TOP of the vertical columns, but came down upon the floor truss connections. The floor truss connections, being MUCH weaker than the small truss connnections, would have either sheared off of bent downwards. How could those small connections slow the velocity or even produce a jolt?

 

[FineWine]

FW,

You have to consider the PATHWAY that the forces (i.e., from weight & momentum) take in order to be transmitted from one component to another. These forces have to be transmitted thru physically touching components.

Heiwa is right that the upper floors do not transmit their weight & momentum DIRECTLY. Since they are not DIRECTLY touching floor 97. But the upper floors DO connect to the support columns and the support columns DO impact on Floor 97. So, ALL of the upper floors DO transmit both their weight & momentum to Floor 97 THRU the support columns. Actually thru approximately 1/2 the core & external columns.

Heiwa is right that the lower column stubs will also impact on the underside of floor 98. This is a version of the hunter with a spear, allowing the lion to charge him, burying the back end of the spear in the ground, and allowing the lion's momentum to impale itself on the end of the spear. (My hat's off to ANYONE who has ever pulled off this stunt...)

So there WILL be a mutual destruction of both Floors 97 & 98.

But after that first floor's destruction, the picture changes.

As I tried to explain here: http://www.internationalskeptics.com/forums/showthread.php?postid=4743226 , there are some subtle effects that cause the destruction to not be symmetric, up vs. down. This symmetic destruction is the core of Heiwa's (incorrect) contention.

There are two components that are responsible for the destruction of the floors: the column stubs and the mass of the debris that has been broken free in the crush zone. The column stubs are only significant during the 97th & 98th floor's destruction. After that, lateral forces simply sweep the column stubs aside.

The descending mass is all that matters. And as I tried to show, that mass of debris will collect at the bottom of the descending (& growing) upper body. And it will interleaf and connect to the upper blocks columns. And therefore that layer of debris will transmit the weight of the entire upper block (by virtue of its connection to the columns) and protect the upper block from further destruction.

As I tried to explain in that post, by the time the crush zone reaches any given floor, that floor has ALREADY had 2/3rds of it supports ripped apart. With this level of destruction, it has already been turned for the most part into loosely connected debris. Much of it already falling.

A piece of free falling debris, descending at 10 mph, puts far, far less impact on the 50 mph descending mass than that same piece of debris would have if it had been stationary & firmly fixed to its supports. This is a large part of the reason for the asymmetric destruction.

So, to answer your question, the placement of lawn chairs & lead plates is, of course, irrelevant to the ultimate fate of the universe.

You have been GROSSLY unfair to Heiwa, FW. You've expected him to discuss the issues with honesty and maturity.

How COULD you...?

Tom

Thanks, Tom, for a typically lucid and informative response. It is nothing short of amazing that Heiwa can address an audience highly familiar with videos and photos showing external columns being stripped away and pretend that the columns all remain standing, spearing the falling debris. Why do stupid people think everyone else is stupid too?

 

[FineWine]

We are talking about the equivalent of a one-acre homogenous block of concrete 30 feet thick. When you break a block like that into the small pieces that we typically see in the rubble you may realise just how much cincrete r missing from the rubble. That can maybe be explained by the pulverisation we saw but the missing three quarters of a mile of wire mesh reinforcing cannot be explained in this way. ..and in my opinion neither can the 5,000 missing floorpans or the thousands of tons of missing core columns.

You have been caught lying again. No core columns were missing.

 

[FineWine]

Yes I'm awfully awfully embarrassed. But never mind is what I say. See- I told you it was a lot of mesh that's missing from the rubble. The best part of a square mile in fact. I notice you didn't have any sensible answers to the question either. What about the '' Find the missing square mile of rebar '' Challenge.
Do the sexual references get your rocks off then ? I was always uneasy about you following me around. A groupie is one thing but....

You don't even know what you're trying to claim anymore. Pathetic.

 

[FineWine]

Well, you say that 13 floors (#98-110) abt 4 m apart in a 53 m high assembly of floors drop and hit one floor, #97.

But floor #110 is 53 m away from floor #97! The only floor that floor #110 can contact is floor#109, but for that to happen you have to remove all columns between floors #109-110.

So, let's agree that it is an assembly of floors (#98-110), part C, that is alleged to contact floor #97 that happens to be part of another assembly of floors (#1-97), part A, i.e. part C contacts part A (as suggested by Bazant).

Bazant suggests further that part C is rigid (uniform density, it will not deform, it is indestructible at this time) but it is nonsense. And therefore Bazant's model is nonsense.

Now, you suggest that an assembly of floors, upper part C, is capable to one-way crush down lower part A, floor by floor, i.e. 97 impacts take place.

My opinion is clear! Your suggestion is impossible! Actually a ridiculous suggestion. Because at impact C on A, local failures will occur in both C and A. The weak elements or weak connections in both C and A adjacent to the impact interface fail first. Energy is absorbed as local failures. A jolt (decelaration - unit m/s²) of C should be observed. Then damaged elements will displace and contact other elements. Friction develops. More energy is now absorbed as friction. Etc, etc. And after a while of more local failures/friction the destruction is arrested. Happens every time you drop a part C of a structure A on the rest of A. It should take less than ONE second in the WTC 1 case.

This is the reason Why a one-way Crush down is not possible = topic = post #1.

Anyone suggesting that part C structure can one-way crush down part A structure is complicit to mass murder! Let's expand the thread to include that suggestion.

Will you ever stop lying about the "indestructible part C"? Nobody makes this claim. Have you no shame at all?

 

[alienentity]

Ok. Someone PLEASE explain this to me as I seem to be missing some major point here.

Why are the columns being used as the reason there should be a "jolt" or "loss in velocity"? If the columns were that strong, wouldn't it be the floor truss connections that would be subject to the load of the upper falling mass?

I mean the perimeter AND core columns were outside the perimeter of the concrete floors.

The upper mass, in what I envision, didn't come down on TOP of the vertical columns, but came down upon the floor truss connections. The floor truss connections, being MUCH weaker than the small truss connnections, would have either sheared off of bent downwards. How could those small connections slow the velocity or even produce a jolt?

My understanding of it (from reading analysis by various engineers, such as Bazant etc) is that there is no serious question that the kinetic energy generated by the downward, gravitationally-driven movement of the upper blocks was easily sufficient to continue the collapse all the way down to the foundations.
By making crude simplifications of the scenario, never intended to be more than computational guides, Bazant was able to provide some solid calculations about the expected strength of the structure and the forces which destroyed it.

The actual collapse is far more complex, and did not behave in the way a simple caricature does - Tony S is using the simplified caricature and expecting it to model precisely what the more complex object did.

Of course that was never the intention of Bazant's calculations at all.

Because Tony is unwilling to accept the inevitability of the collapse, he has to handwave away the unmistakable fact that the towers did NOT collapse at the rate of freefall acceleration, but were slowed by the structure, as expected. The fact that structure provided resistance demonstrates that it was not a controlled demolition at all, but a complex gravitational collapse initiated by the failure of structure due to plane impacts and fires.

That is why the engineering community at large has no need to pursue convoluted conspiracy theories to explain the collapses, and it never will.

If you read more of Tony Szamboti's posts on other internet forums (sciforums.com for example) you'll see he holds a number of corresponding goofball viewpoints, asking questions such as
'Why do you think the building collapses initiated on floors just above where the aircraft impact damage had occurred instead of where the damage was, which also had fire?'
'The collapses of the twin towers both initiated just at the very top edges of the impact zones, where there was almost no fuel and an insignificant number of columns damaged'
'Isn't it amazing that the columns from these initiation floors weren't saved, to show us just how hot they got? That would have nipped any conspiracy charges right in the bud. It is very suspicious that these columns weren't saved and no amount of obfuscation and spin can end that suspicion.

However, it could also be where a demolition could be initiated, since they were the first floors above which had little damage and the planted thermite charges would not have been upset.'

Elsewhere, as Tony has already written in this stupid Heiwa thread, he believes that mythical nanothermite materials, none of which he has seen, nor tested, nor seen tested, were actually responsible for the tower collapses, which did not require explosives anyway (as we have seen). So he not only argues (apparently expecting to be taken seriously!) that the plane impacts were merely a smokescreen for the REAL destruction by mythical compounds which, in his Harry Potter fantasy can magically accomplish this in a virtually undetectable way. 'Nano-thermite's brisance and noise level for a given charge is also tailorable by changing the size of the particles. Explosive noise and force away from the target could also be kept to a minimum by tamping.'
Please note that Tony is extrapolating his entire nanothermite theory from some obscure references about research into nanothermite weapons made in 2001. He's paraphrasing the comments, trying to co-opt them into the truthersphere for building demolition. I kid you not.
http://sciforums.com/showthread.php?p=2287107

Skeptics have sarcastically termed such fantasy, low-noise explosives as 'hush-a-boom' explosives. There is good reason for such derision, and it's not even worth mentioning why, I hope. (you know, a high-velocity, high explosive charge that is somehow quiet?!? Oy vay!)

Dr. Frank Greening has also discovered some large errors in Tony's paper, discussed here by Dr. Greening
http://the911forum.freeforums.org/newton-s-3rd-law-and-the-collapse-of-wtc-1-t153.html

 

[GlennB]

The actual collapse is far more complex, and did not behave in the way a simple caricature does - Tony S is using the simplified caricature and expecting it to model precisely what the more complex object did.

<snipped because you can read it all above>

Dr. Frank Greening has also discovered some large errors in Tony's paper, discussed here by Dr. Greening
http://the911forum.freeforums.org/newton-s-3rd-law-and-the-collapse-of-wtc-1-t153.html

Amen. Excellent post. And the link is well worth reading.

 

[alienentity]

Some very relevant observations on the effect of the 'impulse' (jolt) by OneWhiteEye

'An impulse at one end of a deformable body does not translate to the same acceleration over the entire structure.'
'..the 'masses' interspersed with the 'springs' provide both material inertia and internal flexure, thus satisfying Newton's 3rd while yet assuring that the roofline will display the least effect of the resistance impulse delivered below.'

Mon Apr 20, 2009 6:50 pm
http://the911forum.freeforums.org/newton-s-3rd-law-and-the-collapse-of-wtc-1-t153.html#p2756

 

[Heiwa]

Ok. Someone PLEASE explain this to me as I seem to be missing some major point here.

Why are the columns being used as the reason there should be a "jolt" or "loss in velocity"? If the columns were that strong, wouldn't it be the floor truss connections that would be subject to the load of the upper falling mass?

I mean the perimeter AND core columns were outside the perimeter of the concrete floors.

The upper mass, in what I envision, didn't come down on TOP of the vertical columns, but came down upon the floor truss connections. The floor truss connections, being MUCH weaker than the small truss connnections, would have either sheared off of bent downwards. How could those small connections slow the velocity or even produce a jolt?

It is quite simple! It does not matter what element or connection fails at impact due to a moving mass of any kind (part C) hitting a static structure (part A) to produce a jolt! Energy is absorbed and the only available energy is that of the moving mass part C. This mass thus transmits energy to something else (an element or a connection that breaks) and must slow down = jolt.

The energy applied by C is quite small (WTC 1)! A couple of 100's kWh. Say 300! To break elements and connections require plenty of energy, say 100 kWh. So part C must slow down accordingly.