Kenetic Energy, Column Bowing and the "Progressive Collapses" of WTC 1 and 2

So I have been wondering something...

If all of the official stories regarding the collapse of WTC 1 and WTC 2 rely on:

1. A single floor of columns, core and perimeter, failing (all at once?).
2. The weight of the floors above the failed floor falling the height of a floor.
3. The kinetic energy of the falling "block" SLAMMING into the intact floor below.
4. The KE is transfered to the INTACT core and perimeter columns.
5. The intact floor fails, core and perimeter columns (all at once AND the KE stays the same or INCREASES?)
6. this process continues through all remaining floors...

If, as according to official sources, during step three above, the KE is transfered, IF ONLY FOR A SECOND, through the ENTIRE HEIGHT of the intact perimeter columns...

Why do we not see any bowing or deformation of the perimeter columns further down the building as the KE is transfered to them?

How is only one floor crushed at a time when the KE should be "pile driving" the entire height of the columns all the way down to the bedrock?

Why is there no delay introduced from the resistance offered by the intact floors? That is, why is collapse speed maintained or even accelerated?

Thanks.


[edit on 5-4-2007 by Pootie]

More importantly, if KE is conserved, then it is required by a specific law of physics that the velocity towards the ground decreases. Instead, the velocity remained constant, each floor popping out at a constant rate, to the point of seeming mechanical.

When two bodies collide and continue moving together, the increased total mass requires the net velocity to decrease proportionally for the total KE to remain the same. This is an inelastic collision, as most people tend to assume.

hyperphysics.phy-astr.gsu.edu...


Remember, though, that not even NIST backs the pancake theory anymore. For those of you that didn't know this, it's because they don't care what you believe, as long as they sell the "natural collapse" line.

[edit on 5-4-2007 by bsbray11]

The first floor to fail would have done so from failure of the beams. Every floor after that would have failed from failure of the joints as the impulse forces would increase while the pressure forces decreased.

When still intact, the weight is transmitted through the beams and therefor they must fail first, but after that first floor goes the weight is no longer directly down the columns and the shear forces would pop out the rivets.

Originally posted by bsbray11
More importantly, if KE is conserved, then it is required by a specific law of physics that the velocity towards the ground decreases. Instead, the velocity remained constant, each floor popping out at a constant rate, to the point of seeming mechanical.

I have no particular feelings on the building collapse, but I am passionate about physics....so...

A steel frame building is NOT a single uniform rigid mass, it's hundreds of thousands of non-uniform masses. You're applying a law incorrectly.

Also, KE is not conserved in almost any real world event. Energy is, and is constantly transferring between Kinetic, Potential, and Thermal (molecular kinetic).

Trying to apply physics to something of this complexity requires massive computing power. To imply otherwise is disingenuous.

Originally posted by Quest
The first floor to fail would have done so from failure of the beams.

If this is the case then why were the connections sheared too? If they didn't, then you can't have falling floors.

Every floor after that would have failed from failure of the joints as the impulse forces would increase while the pressure forces decreased.

The velocity would still decrease even if this were true. But the impulse force, in reality, would have been decreasing in proportion to the normal force the whole way down.

Reason being?

Mass was constantly being thrown out of the collapse, as the structure became more and more massive all the way down. In other words, the mass coming down was decreasing, as the "solidness" of all the mass below was increasing.

When still intact, the weight is transmitted through the beams and therefor they must fail first, but after that first floor goes the weight is no longer directly down the columns and the shear forces would pop out the rivets.

Another problem is that you'd have to take out completely unprecedented amounts of structural integrity for a failure to even begin.

Steel structures have been engulfed in intensely hot fires in labs since the 1980s, and never have they collapsed because of it. This is real science. The only case where steel has failed from fire, is the Windsor Tower's outer columns, which had very small diameters and were exposed to intense heat for almost a whole 24 hours. Only localized collapses resulted.

Originally posted by Quest
A steel frame building is NOT a single uniform rigid mass, it's hundreds of thousands of non-uniform masses. You're applying a law incorrectly.

Talk to a structural engineer. A major goal with any structure is to make it as solid as possible, and this is why everything is supposed to be bolted and welded solid together. It essentially becomes a single mass, and this is the goal.

The one exception here is the trusses, not in their connections to the columns, but in their connections to each other. Why would a whole floor's worth of them fail simultaneously? The logical answer is that they wouldn't, and neither should all 4 corners of WTC1 have began falling instantaneously.

Also, KE is not conserved in almost any real world event. Energy is, and is constantly transferring between Kinetic, Potential, and Thermal (molecular kinetic).

That only hurts your case, buddy, because all of that energy going to smashing the concrete and etc. is even less kinetic energy for you to apply between floors. I was being conservative by ignoring those things for the sake of argument.

[edit on 5-4-2007 by bsbray11]

the official line is that the kinetic energy of a one storey drop is more than enough to shatter the strength of the floor below it. they apply the entire weight of the broken off cap to the load bearing capabilities of the FLOORS, ignoring the geometry of the situation.

however, the structure was not a stack of boxes. it was a steel weave. it's why they didn't do a proper model of the collapse. they can't make it fall more than a few storeys, even with completely 'tweaked', unrealistic values and assumptions.

'the rivets popped'... HAHAHAHA!!!! good one.


just to get you up to speed, the core columns were welded together from top to bottom, and the perimeter columns were in three storey high, by 3 columns wide (connected with three spandrel plates) sections. very few of these 'trees' were compromised, and they tended to 'pop their rivets' while the welds held. the core has ZERO EXCUSE for coming apart at the same time as the outer cage and floor system.

picture this... pulling down a birds nest with a spider web. what breaks? the web or the umpteen dozen twigs woven into the branch?
because the official NISTian explanation for the collapse initiation is that the spider web pulled the bird's nest out of the tree. (ie. the skinny, lightweight floor trusses pulled in the MASSIVE perimeter)

the thing that is really blowing me away lately, is how people REFUSE to see the motive behind the attacks.

did this in any way benefit the alleged perps? the exact opposite is true. their whole advantage was stealth, as terrorists, but this stunt turned the entire might of the us army on them. did they think that wouldn't happen?

so, now, there is a HOLOCAUST being perpetrated on the muslim world.

and, the 'victims', are getting filthy rich off of weapons manufacturing, insurance claims, and no-bid contracts for all things war related, and in 'fighting for freedom', freedom has been REMOVED from MANY of the sacrosanct constitutional rights of the sovereign individuals of the united states of america, by the same crew who is preaching protection of it.

oh yeah, and, anthrax. remember the anthrax MURDERS and the complete 'cremation of care' on that crime by 'law enforcement', and 'the news you can trust'.

Why is the explanation he gave not accurate. The WTC was a unique building and design. It was designed for wind sheer and commercial space, not for a large commercial jet to slam into it at 500mph. This is an old arguement, but one not bought up enough.

There was no concrete in the core to be used as fireproofing as it in almost every other building in existence. This made the structure again very unique.

Are we in agreeance that it is a unique design?


[edit on 5-4-2007 by esdad71]

Originally posted by esdad71
Why is the explanation he gave not accurate. Sounds fine to me, but it does not include explosives or lasers so it must not be the truth.

Just because something sounds good to you does not mean it obeys the laws of physics. No need to derail a thread where actual discussion is occurring. I must have missed where anyone brought up lasers or explosives... can you please show me?

Originally posted by Quest
Trying to apply physics to something of this complexity requires massive computing power. To imply otherwise is disingenuous.

The required energy inputs are so far above and beyond the energy available in a gravity driven collapse, it is disingenuous to claim a computer is required to apply the laws of physics.

OK, i edited it, now answer the question. Thanks. Also, what are you using to back up this statement,

by Pootie
The required energy inputs are so far above and beyond the energy available in a gravity driven collapse,

Also do you know what the required energy would be to collapse that building?


[edit on 5-4-2007 by esdad71]

[edit on 5-4-2007 by esdad71]

Originally posted by esdad71
Are we in agreeance that it is a unique design?

Yes. It was uniquely OVERBUILT to withstand hurricane force winds, take a hit from a large jet liner (speeds are in question), survive fires (it did)... One tower even EASILY survived a large TRUCK BOMB with minimal damage.

Esdad,

What is so unique about the towers? You have an exterior column holding up a composite deck attached at the other end to an interior column. This is a very basic design in engineering. Matter of fact, it is the easiest to analyse because it is a determinate structure. The towers were not so unique that we can't use the laws of physics to analyse them.

It was not overbuilt, and it was not designed to survive the impact of a aircraft striking it at 500 mph. The theory at the time was a plane landing lost in fog with an airspeed of less than 200 mph. YOu are confusing an interview with fact.

One tower survived a bombing, but I would not say easily. This was a miscalculation on the part of the terrorsits, who wanted the one tower to collapse into the other. The bomb itself was not as powerful as it was supposed to be and this was a lucky break.

Now, we agree it was a unique design, so that means there is no precendent for a fire of this magnitude? Is this also correct?

Originally posted by esdad71
Also do you know what the required energy would be to collapse that building?

Well...

Energy to pulverize EVERYTHING except paper and steel to fragments/dust
+
Energy to create ALL THE HEAT in the pile that lasted months
+
Energy to break all core box columns
+
Energy to BREAK and THROW perimeter columns UP TO HUNDREDS of feet lodging them into buildings
+
Energy to push the dust cloud out for MILES
+
Energy to maintain or accelerate collapse speed (i.e. NOT slow down)
+
Energy...

Energy is a ZERO SUM GAME DAD. The ONLY energy input available is the MASS of the block above the "failed floor" x Gravity. Energy is never created or destroyed... it only changes forms.

There is an enormous energy deficit. Exact math is not required to see that.

I am not stating that it is something that defies the laws of physics, but could you please show me more than 5 other buildings designed and built the same way?

Please explain, since we are talking physics, if something is supposed to handle a load it is not designed to and gravity is applied, will it collapse?

Esdad, why don't you drop the generic crap like "it was unique" and "it wasn't overbuilt" (which is complete BULL), and talk actual physics or engineering for a change? Don't like putting yourself in a position where people can actually check what you're saying?

Griff is a civil engineer, he works with building structures for a living and he's telling you the design is common. It was freaking minimalistic in design. I can only imagine what you'd be saying if it was the Empire State Building or any other skyscraper, because they're all more "unique" than the towers by far.

And saying they weren't overbuilt just further shows you don't know what you're talking about. If they weren't over-engineered then they would have immediately collapsed as soon as 1 column was compromised. Think. Those towers were massively overdesigned.

[edit on 5-4-2007 by bsbray11]

Originally posted by esdad71
It was not overbuilt, and it was not designed to survive the impact of a aircraft striking it at 500 mph. The theory at the time was a plane landing lost in fog with an airspeed of less than 200 mph. YOu are confusing an interview with fact.

Dude... I said "SPEEDS ARE IN QUESTION" for a reason. are you just typing random characters?

Originally posted by esdad71
One tower survived a bombing

Agreed..

Originally posted by esdad71
Now, we agree it was a unique design, so that means there is no precendent for a fire of this magnitude? Is this also correct?

No. The fires were relatively SMALL considering the size of the building and other comparable high rise fires. Call your local fireman.

Originally posted by esdad71
Please explain, since we are talking physics, if something is supposed to handle a load it is not designed to and gravity is applied, will it collapse?

No. It was designed to lose columns and stay standing. You are being very misleading.

Dad, no offense, but unless you want to talk Energy, which was the point of the thread, please stop trying to derail it.

I am not trying to derail it. I understand that Griff is a civil engineer and I do not need to call the local fire department.

Please show me similar structure of that size? There are thousands of large buildings around the world, but almost every single one was designed unlike this one. Most have much more concrete for rigidity and fireproofing? This is correct, right?

It was not designed to loose columns and still stand. If I remember correctly, a building's safety is designed only to withstand fire, and that is for 2 hours? This is correct, right Griff?

It was designed to withstand Hurricane force winds intact, not cut and missing supports. I understand and have read a fw different KE reports and how some feel that he displacement of energy during the fall was not enough to continue to collapse. However, this is not a normal building, it is unique.

IN a solid concrete structure, you are building floor upon floor upon floor. WIth the WTC, you have an outer frame, with the floors, fo lack of a better word, placed and then bolted in. There are numerous points of weakness that are evident because of the unique design. I am jsut trying point out someting that I think is crucial since it was not built like other common structures.