Moderated Continuation - Why a one-way Crush down is not possible

[tfk]

Heiwa

Thanks for agreeing that total forces/moments at any point in any structure is zero so that the point is not flying away.

.
Thank you for agreeing that your point was trivial and irrelevant to the definition of the term "rigid body".
.
quote=Heiwa;4970848]
So when Bazant assumes that a complete assembly of elements is rigid in his WTC 1 analysis, you know that the complete analysis is fake!
[/quote]
.
Your assertion is so looney that all I can do is wish I knew where they keep those laughing dogs.

You'd get a dozen.

Tom

PS.
Are you ever going to answer my questions? Is it fear that your silliness will be exposed? Or just simple French rudeness?

 

[tfk]

Question was 'Any errors noted'? Your opinion is of little interest.

Too Numerous To Count.

 

[Paulhoff]

Go to smilies, More, when the new window opens go to Specials.





and here are your 12.

Paul

 

[BasqueArch]

In the Case Of :
Heiwa, Richard Gage, Tony Szamboti, David Chandler, Craig Ranke, Aldo Marquis, and that 94 year old guy engineer persuaded-by-that-cute-interior-design-intern-gal to sign the petition, et al
vs.
JREF, 92% of the world's population, et al."​

Bailiff: All rise ... the Right Honorable Rames Jandy has entered !

Judge: Mr. Heiwa. Please state your case why WTCs1,2 one-way crush down is not possible.

Heiwa: *cough*

OK, the pestle is part F and the mortar is part D. Say you drop the pestle F in the mortar D and ... nothing happens! No rubble, part E develops at all. Are you really suggesting that a pestle can one-way crush down a mortar? LOLOL. Please demonstrate this with any structure, let's call it D with a part F dropping on it producing rubble that is compacted E. 1. No - a rigid body cannot be changed structurally in any respect.2. There is no such thing as a 'collapse wave' or a one-way crush down in structural damage analysis! In any structural collision only elements and connections break and broken elements may contact and rub against each other, which require energy. The weakest elements/connections fail first. Only local failures take place.3. There is no such thing as a 'crush down'; e.g. small part C being dropped on and one way crushing down bigger part A of same structure. The local failures are arrested when there is no more energy available. It would take less than a second in the WTC 1 case. 4. It seems there will be many small impacts unless some players, Hollywood style, just go through the walls.5. You introduced the IKEA book case box in the discussion for some strange reason.Now, I look forward to your explanations and evidence that an assembly of elements in collision will produce rubble that first compacts itself and then destroys anything in its way. Exactly, you start to learn. One reason why a one-way crush down is not possible is that part C is not rigid, as assumed by Bazant and NIST, so it is the first to absorb energy in a collision ... that is soon arrested. This simple fact cannot be repeated too often. LOL! Trapped rubble delivers a GREATER impact load!! Can you describe this phenomenon in simple terms! I have a structure! I drop a piece, part C, of this structure on it, part A, a lower part. Big impact load! Does part C suddenly produce rubble, part B, that impacts part A, again, and again? acccording Bazant, YES! In my simple opinion part A first decelerates part C (the jolt) and then starts to locally damage part C. Part C has no chance to produce and rubble (B)) that starts impacting anything, incl. A. But maybe I don't understand these things? So please, explain! Aha, now I understand how your rubble can demolish solid structure. The rubble becomes rigid for a while depending on the context and then becomes rubble again. The NWO physics in a nut shell. Thanks. So we can conclude that only in NWO physics a one-way crush down is possible? ??? Nobody has so far been able to show that a one-way crush down is possible! Reason is that it is against the Björkman axiom of structural damages. Pls google for that.Richard Gage is a top class guy that supports me.I am eagerly awaiting your evidence that broken elements, produced by a force F1 at an impact, compact themselves to solid rubble in contact with something and that this compacted rubble in turn impacts and/or applies a force F2 on something, again, poor something, that is bigger than the initial force F1. A simple energy balance would help, you know, energy is applied, energy breaks loose elements, energy is used to compact the elements, etc, etc. Well, from videos we see big sections of wall perimeter columns say 12 m tall, just bolted together at their ends top/btm (the bracing) with the bolts having been sheared off, flying away laterally. No bending of these columns as far as I am concerned. The energy applied is simply a function of drop height applied. The official story in basic physics is that a part C of a structure A (C<1/10A) cannot one-way crush down A when dropped by gravity on A. Little C cannot apply the energy required without destroying itself first. Normally C just bounces on A or there are some local failures and arrest of local failures.What are you trying to prove here? A new way of controlled demolition of a building? Put plenty of funny people up top ... and a one-way crush down takes place? Sorry, you are supposed to drop the complete upper part C on lower part A and then demonstrate that part C can one-way crush down A. So there are now two possibilities? Upper part C is rigid and one-way crushes down part A or part C is not-rigid and collapses (like pancakes), becomes compacted rubble, part B, that one-way crushes down part A. So you say that to destroy a structure A, you only have to destroy some floors up top of structure A ... and the whole structure A collapses, like a house of cards, incl. the core columns. If that's so, we have more clear evidence that the Bazant & Co's and Seffen's theories are not valid. Thanks. Now, what about your solid rubble compaction theory - the rubble Box! - that is supposed to crush anything. Does it tally with your video observations? Pls explain again how rubble is compacted when part C of structure A impacts A and one-way crushes A. KISS. Serious attempts to make it very simple and easy? lol! WITH EVERY ASSUMPTION TO STOP THE COLLAPSE? LOL!OK, put all that info together and produce a structure A that will one-way crush down when you drop a part C (C=1/10A) on it. Keep It Simple, Stupid (= KISS). BTW in civilized Europe engineering universities are free of charge as higher education is seen as a national investment so you don't pay up then ... but later with your taxes. Results are good engineers,Actually, when the structure was built the top floors were not even there ... and there was no collapse! According Bazant that you refer to there are three parts C, A and B. C one-way crushes down A into rubble B! C = 1/10 A, B = Arubble = 0.25A, i.e. original A compacted 4X. At end of first step B then crushes up C, etc, etc. Pls, study the Bazant paper and produce a structure A. According Bazant 'the collapsing floors' are assemblied in an upper part C that is rigid, thus they never collapse! They are one 'block'. Rigid! This funny block, actually part C, then is assumed to impact part A, another assembly of floors that is not rigid. When C impacts the top floor of A, there are 97 floors in A, that poor floor is compacted into a rubble part B! Rubble part B ... and rigid part C ... then repeat this treatment of A 96 times, i.e. A becomes smaller and smaller and B bigger and bigger until A = 0! Crush down completed! When A=0, B attacks C, suddenly non-rigid and weak, that becomes part of B. Crush up! When C = 0, crush-up is completed. No core spires, etc, could survive this amazing theory. Then only big B remains, plenty of rubble, 100 m tall, and POUFF becomes a heap of rubble rubble on ground. NWO physics of the worst kind. I am sorry to inform you only fools believe in it. We are still awaiting tfk:s explanation how B is being compacted, etc, etc. I assume tfk is consulting NWO chiefs like Bazant to sort it out? Sorry, in either case part A will arrest the local failures. We all know that part C is not rigid so the Bazant theory is wrong.Then we have the rubble compaction theory, which tfk is supposed to clarify. I have tried to drop many things none of which compacts itself into solid rubble. When I drop Comething it breaks into small pieces that cannot break Anything but I am ready to learn. I have already shown (post #1 of original thread, etc) that it is not possible. You are supposed to prove me wrong. However, tfk thinks otherwise and suggests in some posts above that C first destroys something of A or C, not really clear, that becomes rubble, part B (B as in Box), and that this rubble then compacts itself someway or another - not really clear either as most of the tfk posts - and then - the miracle - one-way crushes A down to ground. I really look forward to hearing how this is possible!Actually I don't but tfk produces LOL so I make an exception. The force that upper part C applies on lower part A at impact C on A is always the same as the force art A applies on part C at same impact regardless of drop height. = As A>C (A can absorb more strain energy than C) A will always arrest or destroy C, i.e. C cannot one-way crush down A as suggested by NIST, Bazant, Seffen and Co. So how can the bolts - the bracing - shear off, if the column itself is not affected? Yes, where does it come from? From the top 12 storeys (part C) or from the 98 storeys (part A)? And why would it start to one-way crush down part A. Actually much too little potential energy is available and it is easily absorbed as local failures and friction between displaced elements at the interface. The local failures are arrested at once. A correct energy balance is the right way to prove that a one-way collapse is not possible. The upper part C of WTC 1 is above the yellow lines applied on the photos of the WTC 1 tower at say floor 97 and the lower structure is below. Snap shot left above is just before destruction starts and snap shot right a few seconds later. It should be clear to anybody that the upper part C above the yellow lines simply disappears in a big cloud of smoke and dust, while nothing has happened to the lower structure, part A, of WTC 1. Evidently gravity alone cannot destroy, shorten, the upper part C before it, the upper part C is supposed to impact and collide with and crush down WTC 1 below! Why is there so much smoke, debris and vertical deformation of the upper part C only? It, the upper part C, is simply destroyed by some energetic material devices and there is no collision with the lower part. Same devices are apparently used to destroy the lower structure of WTC 1 a few seconds later. In the official accounts of the destruction of WTC 1 the upper part C is supposed to remain intact and produce one-way crushing until the end of destruction and be crushed against the ground. And have you found any columns with failed splices in the rubble? And how to apply a gravity force on a vertical column so that it nears buckling? I like the moving display of two types of 'collisions' between a moving and stationary (that should be fixed to ground) object in your link. The jolt is quite evident and it is of course missing in any videos of the WTC destruction. But in real collisions both objects suffer local failures and are subject to friction between elements at the interface and that's where the energy is absorbed. I am eagerly awaiting your evidence that broken elements, produced by a force F1 at an impact, compact themselves to solid rubble in contact with something and that this compacted rubble in turn impacts and/or applies a force F2 on something, again, poor something, that is bigger than the initial force F1.A simple energy balance would help, you know, energy is applied, energy breaks loose elements, energy is used to compact the elements, etc, etc. What about your rubble compaction paper? Any progress? You know, that IKEA book case that disassemblies itself when hitting solid ground and becomes solid rubble that destroys the ground and everything. I look forward to it! Don't you know that a one-way crush down is not possible?

Judge: Thank you Mr. Heiwa, very impressive. You have presented culinary, artistic, imaginative and vegetarian aguments why a one-way crush down is not possible and why bumblebees can't fly.

Counsel for the defense, Mr ah... Giraffe. Please state your case.

JREF: Your honor, worthy jury members, esteemed codpieceholders:

One; The visual evidence proves that the collapse of WTCs1,2 was gravity driven.
http://www.internationalskeptics.com/forums/showthread.php?p=4964563#post4964563 post#1

Two; The visual evidence proves that explosives/thermite were not employed.
http://www.internationalskeptics.com/forums/showthread.php?t=149420 post#1

Three; Therefore no one cares if a one-way crush down is possible. Reality trumps hypotheses and the Towers fell because ******* religious fanatics attacked them .
Your honor,the defense rests.

(The jury composed of 11 rationals and one religious fundamentalist returns 4 minutes later)

Judge: What say you all.

Jury foreman: We find the defendants, JREFers, righteously right, and that the plaintiffs are to pay all the defendants' associated costs.

Judge: Close the lights turn off the door.

*BANG*

 

[Justin39640]

Yet another Newton can be seen at 2:00 in this video



Man I am old! I remember watching these as a kid.

yet another

lol

 

[tsig]

Why bother to mention it? The liars are lying. That's all they do. No faculty scientists wrote to Waterboy and the deranged Jew-hater to express their fear of reprisals. I wonder how that would work. I supopose the faculty, 98% of its members virulently opposed to George Bush and his policies, wouldn't tolerate anyone speaking badly of Republicans.

Whenever you seem to hit rock-bottom, you find a way to dig down a bit deeper.

When they hit rock bottom they get out the jackhammer.

 

[MIKILLINI]

Yet another Newton can be seen at 2:00 in this video



Man I am old! I remember watching these as a kid.

So do I. Bill played the parrot in that video.

 

[Oscar]

BasqueArch, I enjoyed your post very much. Very good.

 

[BadBoy]

Hey Tim,

Sorry, took a bit to spring free the time.

Your instincts are right on the money. There is an asymmetry to the damage that needs to be explained.

If the collision between the upper & lower parts had been horizonal, then the damage would have been symmetric into both pieces.

So what is the source of the asymmetry? Exactly what your instincts tell you: Gravity.

In a sense, it's the difference between jumping on somebody & having somebody jump on you. But with an extra twist...

The best way to view this is as the side of an incredibly steep slope subject to a rockslide. All the various rocks have had braces carefully designed & placed under them. Unfortunately, all those little braces are "mutually supporting". They cannot withstand their own load if too many of the adjacent braces are gone. And now, when the avalanche starts, even tho every individual collision does obey Newton's 3rd law (action = reaction), the whole landslide moves inexorably downhill once it gets going.

The twist is that you're going to ride down the avalanche in a shed above the debris. You'll see what I mean at the end of this post.

Again, the asymmetry is provided by gravity.

So, I think the question question of "why it progressed to the street" is simple. Just like an avalanche, it gathers momentum & mass as it moves down.

The separate (& independent) question is "why did it not move up into Part A?"

Unless you're pretty good with math, it's tough to get a sense of this from Bazant's paper (IMO). His is not a model of what really happened. It is idealized to favor an arrested collapse. And his idealizations are tough to translate into "what does this say about the real building as it came down?"

To get a gut feel, imagine that you are inside the upper block of the building, at about the 102nd floor, and everything below you, down to the crush floor, is transparent.

Before the collapse began, several of the floors on the 97th thru 99th floors had collapsed. This was seen from outside the building. Others were sagging and were pulling in on the external columns (& out on the core columns). Suddenly the connections failed, and the peripheral columns flung outward, becoming massively weaker (because of unsupported length & bowing).

As the collapse begins, the columns of the 98th floor buckle. They do NOT fail as Bazant describes them in any of his papers. Bazant examines them as if they buckled over a length of one floor, with 3 (or 4) knuckles. [See any of Bazant's papers that describe the columns becoming unstable.] This makes any of the individual straight segments between knuckle points equal to about 3' to 4' long. [Again, this is one of Bazant's "conservative", arrest favoring, idealizations.] Remember, short beam are strong, long ones are weak.

An examination of any of the collapse videos shows that the external columns did not fail like this. They failed at the column to column joints. That means that the lengths of the buckling segments was not 3' to 4', but rather about 36' long. This means that the real failures of virtually complete floor destruction extended up about 3 stories and down 3 stories from the 98th floor. Plus partial destruction up 2 additional & down 2 additional stories.

Lacking lateral support, the core columns buckled too, probably mirroring the outer columns (i.e., 6 floors total collapse, plus 2 up & 2 down partial.)

And when you pull the supports out from under a concrete floor that weight about 2.5 million Kg each, what happens? They all start to fall, together.

But there are still partial connections to the standing lower columns, so they don't free fall. The upper block does. The upper stories (3 stories of rubble first) then overtake the 3 stories of dragging rubble. The point is that the collision velocity between something that is free falling (upper block) and something that is ALMOST free falling (rubble) is much less than between something that is almost free falling (rubble) and something that is stationary (lower floors).

The impacts between the upper block and the rubble is a much less forceful impact than between the rubble and the lower stories precisely because of the lower relative velocities.

Meanwhile, a second effect occurs. The rubble is "packing into the lower 2 - 3 stories of the upper block. It's packing in at a low relative velocity, and it is being tamped in by air pressure and many, many collisions.

Now, we're ready for your observations from the 102nd floor. The debris has been packing in in the stories below you. At fairly low relative velocities. By the time the upper block has fallen 6, 7, or 8 stories, there is a LOT of debris packed into those lower couple of stories of the upper block. This debris became a barrier between the impacts and the upper block. The impacts were happening on the BOTTOM side of the debris. The upper Part A was riding down on the UPPER side of the debris. The growing debris layer PROTECTED the upper block from the destruction.

I tried to describe this in another posting here: http://www.internationalskeptics.com/forums/showthread.php?postid=4743226#post4743226

I hope this helps.

Tom

Hay Tom,

This was excellent , thanks for taking the time and sorry that you had to explain it in such basic terms but it was just what I needed. I hope others reading will benefit too - Im sure they will. (I missed your earlier post, had a quick look and it looks interesting as at first glance it argues Heiwa's point aswell.)

I get it now, though the image of falling in WTC1 looking through a transparant floor will probabl give me nightmares.

You know, its surpising how much affect the truthers have on the population. Its amazing when I bring up debunking 911 in everyday conversation how often someone will reply with "yes, but didnt -they- prove the towers couldnt have fallen by themselves", at least now I can bring some science into the conversation, instead of just saying " dont be a fool"

Cheers

Tim

 

[Heiwa]

Lacking lateral support, the core columns buckled too, probably mirroring the outer columns (i.e., 6 floors total collapse, plus 2 up & 2 down partial.)

I hope this helps.

Tom

LOL! Core columns supported by external floors!

 

[BadBoy]

Not sure what you mean by "external floors" here.

I think I understand why the core columns require lateral support by the floors combined with the external columns, or is this what you are scoffing at. I thought that had already been explained on this thread. Core columns provide vertical support, outside columns and floors provide lateral support. Is this not correct?

 

[bill smith]

Not sure what you mean by "external floors" here.

I think I understand why the core columns require lateral support by the floors combined with the external columns, or is this what you are scoffing at. I thought that had already been explained on this thread. Core columns provide vertical support, outside columns and floors provide lateral support. Is this not correct?

Had say seven floors of the core columns been stripped of internal and external lateral bracing and stood naked and exposed before any impact then it might be possible that they buckled under the weight of the top block (part C).But they might also have plunged into the body of the falling part C.

In reality though the core columns were fully braced from all sides- 100% intact at basically all levels as the collapse wave impacted and progressed apparently crushing all before it.

So the collapse wave is supposed to have crushed what amounted to a massive sturdy block right down onto the ground, The lightest 10& crushing down the strongest and fully intact 90% at close to freefall speed.

 

[funk de fino]

So the collapse wave is supposed to have crushed what amounted to a massive sturdy block right down onto the ground, The lightest 10& crushing down the strongest and fully intact 90% at close to freefall speed.

No, you just made it up.

 

[BadBoy]

Had say seven floors of the core columns been stripped of internal and external lateral bracing and stood naked and exposed before any impact then it might be possible that they buckled under the weight of the top block (part C).But they might also have plunged into the body of the falling part C.

In reality though the core columns were fully braced from all sides- 100% intact at basically all levels as the collapse wave impacted and progressed apparently crushing all before it.

So the collapse wave is supposed to have crushed what amounted to a massive sturdy block right down onto the ground, The lightest 10& crushing down the strongest and fully intact 90% at close to freefall speed.

Well, it did. We all seen it happen. So it must have been possible.
The alternative that your are pushing doesnt compute. There are far/far/far too many problems with it. I would go and rethink your math instead, rather than jumping to very odd conclusions. Nixon wasnt even able to cover up watergate. How would you suppose a conspiracy of this size is possible and we are not talking about bugging the opposition, we are talking about the US government murdering thousands of people - and all just for money, not even for political gain. That dog just dont hunt

If you really believe this, which I dont think you do, then your one can short.

 

[tsig]

Had say seven floors of the core columns been stripped of internal and external lateral bracing and stood naked and exposed before any impact then it might be possible that they buckled under the weight of the top block (part C).But they might also have plunged into the body of the falling part C.

In reality though the core columns were fully braced from all sides- 100% intact at basically all levels as the collapse wave impacted and progressed apparently crushing all before it.

So the collapse wave is supposed to have crushed what amounted to a massive sturdy block right down onto the ground, The lightest 10& crushing down the strongest and fully intact 90% at close to freefall speed.

I saw a building collapse. You keep telling me I didn't.

 

[tfk]

Tim

Not sure what you mean by "external floors" here.

I think I understand why the core columns require lateral support by the floors combined with the external columns, or is this what you are scoffing at. I thought that had already been explained on this thread. Core columns provide vertical support, outside columns and floors provide lateral support. Is this not correct?

.

Close. Not quite.

But you're getting the picture really fast.

What I was referring to, when I said "lateral support" is the whole floor assemblies. The 2D grid of cross trusses, the concrete floor & the connectors.

Think about two incredibly tall, incredibly narrow, parallel walls. Neither wall by itself will stand. Now, you extend multiple planar supports (aka "floors") between the two. Does Wall A support Wall B, or does Wall B support Wall A? Obviously neither. Each supports the other. All the components (walls & floors) are mutually supporting. If any of those major components gets too compromised, the whole structure fails.

In the towers, each major component (wall & floor) is made of many, many individual subassemblies, acting in parallel. So there is a bunch of redundancy. You can lose many subcomponents. But there is a limit. Finally, losing enough subcomponents, the major component fails &, again, the whole structure fails.

This is probably the most important idea to get across: Everyone seems to focus on the strength of the materials, because this is an easy concept to get across. But it is crucial to understand that 90% of the strength of the structure is provided by geometry, not strength. Lose the geometry, lose the building.

Think about those IKEA bookcases that Heiwa has become so fond of. With 1" thick sides, top, bottom & shelves, the whole thing won't even support its own weight without collapsing to the side, much less 5 shelves of books, until you tack on the 1/16" thick cardboard backing that maintains the geometry.

Gotta look at the whole picture, not just the individual components.

Tom

 

[FineWine]

Had say seven floors of the core columns been stripped of internal and external lateral bracing and stood naked and exposed before any impact then it might be possible that they buckled under the weight of the top block (part C).But they might also have plunged into the body of the falling part C.

In reality though the core columns were fully braced from all sides- 100% intact at basically all levels as the collapse wave impacted and progressed apparently crushing all before it.

So the collapse wave is supposed to have crushed what amounted to a massive sturdy block right down onto the ground, The lightest 10& crushing down the strongest and fully intact 90% at close to freefall speed.

Bill--Bill--get a grip. Heiwa is wrong. He doesn't know what he is talking about. The real engineers have exposed him.

You simply can't keep repeating nonsense about a "lightest 10%" and a "fully intact 90%." Listen closely (we realize you've heard this many times, and we understand how deadly it is to your lunacy):

THE THIRTEEN COLLAPSING FLOORS HIT ONE FLOOR, THE FLOOR IMMEDIATELY BELOW;

THEY CRUSH THAT FLOOR, ADDING IT TO THE TOTAL COLLAPSING MASS;

THEN FOURTEEN FLOORS HIT ONE FLOOR, THE FLOOR IMMEDIATELY BELOW;

THEY CRUSH THAT FLOOR, ADDING IT TO THE TOTAL COLLAPSING MASS;

THE PROCESS IS REPEATED UNTIL THE BUILDING HAS BEEN DESTROYED.

Stand in front of a mirror, Bill, and say out loud: The collapsing floors hit ONE floor at a time--ONE FLOOR, not the entire building.

Say this over and over until you never again feel the need to rave about part C hitting part A. Forget part A, Bill. Heiwa is wrong--as wrong as a human can be.

 

[jhunter1163]

Type : dl : (without spaces) to get a laughing dog.

 

[Heiwa]

Not sure what you mean by "external floors" here.

I think I understand why the core columns require lateral support by the floors combined with the external columns, or is this what you are scoffing at. I thought that had already been explained on this thread. Core columns provide vertical support, outside columns and floors provide lateral support. Is this not correct?

The 'external floors' are the pre-fabricated floor assemblies installed between core and perimeter columns. Installed? They are simply put on small angle bars at perimeter/core and then bolted at regular intervals to the angle bars on the perimeter columns and horizontal beams at the core; they are hanging on the angle bars and then bolted.
The weakest element here is the bolt and the angle bar. The bolt may provide some lateral support in shear. Evidently the 'floors' do not support the core! The core is self supporting.

 

[tsig]

The 'external floors' are the pre-fabricated floor assemblies installed between core and perimeter columns. Installed? They are simply put on small angle bars at perimeter/core and then bolted at regular intervals to the angle bars on the perimeter columns and horizontal beams at the core; they are hanging on the angle bars and then bolted.
The weakest element here is the bolt and the angle bar. The bolt may provide some lateral support in shear. Evidently the 'floors' do not support the core! The core is self supporting.

You might have welded too much galvanized in confined spaces.