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Originally posted by ErtaiNaGia
SO, that gives us a rough energy equivalent of 233.7345 tons of TNT.
IOW, about 4x your first estimate.
there are better estimates on the web though. the steel was lighter higher up, so simply dividing the weight by 110 is inaccurate.
Gregory Urich did a very good estimate of the weight on each floor. It's the best I've seen.
Using that data, it's more like 140 tons. Just an FYI and a star for the effort.
Originally posted by ANOK
The laws of motion teach us that the lower floors will push up against the falling floors equally..
Originally posted by Joey Canoli
Give us the load path whereby the falling mass, upon hitting the first intact floor, transfers that momentum onto the lower floors so that their mass can resist.
Originally posted by ANOK
Ke can not increase against resistance.
The floors were either ejected during the collapse
or they stayed within the footprint, if they stayed within the footprint then the collapse would have slowed as floors piled up
and they would be a visible pile of floors, as in a 'pancake collapse.
But that is not what happened, the floors were not stacked up like 'pancakes' post collapse
so the only logical conclusion is that all that dust is the floors being pulverized.
If the floors are being pulverized during the collapse that means mass and Ke are being lost.
If mass and Ke are being lost the collapse can not continue.
For the collapse to continue the mass would have to stay in the footprint, and Ke would have to increase.
If each floors is ten tons, and you have 15 floors dropping on 95, that's 150 tons falling on 950 tons.
Whatever the mass was, or Pe, it's all relative to the whole system.
Originally posted by Joey Canoli
Originally posted by ANOK
The laws of motion teach us that the lower floors will push up against the falling floors equally..
Give us the load path whereby the falling mass, upon hitting the first intact floor, transfers that momentum onto the lower floors so that their mass can resist.
Originally posted by ANOK
Well according to you the truss plates failed allowing the floors to drop
so as soon as the floors impact you are losing Ke and mass.
If the floors stay intact and drop, instead of being pulverized, then they would stack up, what else are they going to do?
They can't both stay in the footprint allowing their mass to do work, and not be there once the collapse was complete
One or the other, and visible post collapse pics show no stack of floors
so only one logical conclusion can be made.
The floors were either ejected during the collapse
Rejected due to lack of evidence.
or they stayed within the footprint, if they stayed within the footprint then the collapse would have slowed as floors piled up
If floors piled up and they were moving at a constant rate, then ke increases.
Your statement is rejected.
and they would be a visible pile of floors, as in a 'pancake collapse.
Baseless assertion that the floors would be intact after a fall of 1000'
Claim is rejected.
But that is not what happened, the floors were not stacked up like 'pancakes' post collapse
Some were indeed stacked up. there has been proof of this. It is not debateable.
Your claim is rejected.
so the only logical conclusion is that all that dust is the floors being pulverized.
How much weight is there?
How much ke is lost as a result?
If the floors are being pulverized during the collapse that means mass and Ke are being lost.
How much mass is lost?
Without answers, your claim that ke is lost is rejected as a bare assertion.
If mass and Ke are being lost the collapse can not continue.
For the collapse to continue the mass would have to stay in the footprint, and Ke would have to increase.
Not all the mass needs to stay in the footprint.
This is an error and is rejected.
If each floors is ten tons, and you have 15 floors dropping on 95, that's 150 tons falling on 950 tons.
Unfortunately for you, 150 tons fell on 10 tons.
Your claim is rejected.
Whatever the mass was, or Pe, it's all relative to the whole system.
Only at the collision point - ie a single floor
Did you see all of that Dust?
Ya, that was the "Ejected" floors.
This means that the Falling object would lose energy as the floor below it deforms from its foundation and supports, and begins accelerating, and at the end of the collision event, the energy of the two objects will be equalized, with kinetic energy being lost in the deformation, and the acceleration of the other object.
Most of that mass was lost as the concrete was turned into a rapidly expanding gas cloud around the demolition site.
wrong, not all of the dust was concrete. How many tons of drywall(sheetrock) was in the building?
Wrong this means that there was an instant load transfer to the suporting trusses below the falling mass. I completely explained it in the link to the other thread.
The energy is transferred to the other truss and I beam bolts and supports. They were not designed to handle the extra sudden shock of energy released when the weight fell on the current standing connections.....
They are designed for a specific application.
Wrong.
There was totally way more weight toi the structure other than the 4 inches of concrete. I made a list of some of the things on the other thread. The elevator shafts were constructed of a sheetrock shell. That is alot of drywall when you add up the walls and the elevators.
As a matter of fact you keep saying rejected.
I am rejecting your comment.
I am done because it will not do anygood anyways.
Everybody ignores the real structural facts and goes along with their own little "physics" explanations.
There are thousands of connections that all have a job to do. If they are damaged, they cannot do their job. There I summed it up nicely for you.
Originally posted by ErtaiNaGia
Did you see all of that Dust?
Ya, that was the "Ejected" floors.
Any falling object that lands on another object that is not falling loses kinetic energy until the two objects are equalized in kinetic energy.
This means that the Falling object would lose energy as the floor below it deforms from its foundation and supports, and begins accelerating, and at the end of the collision event, the energy of the two objects will be equalized, with kinetic energy being lost in the deformation, and the acceleration of the other object.
Baseless assertion that each floor fell 1,000 feet, as opposed to merely falling 12 feet and then stopping as it butted up against the lower floor.
And you are not actually giving us any evidence for your claim.
Most of that mass was lost as the concrete was turned into a rapidly expanding gas cloud around the demolition site.
And since most all of the concrete was turned to dust, that is a substantial figure indeed.
Your claim that ejecta should still be included in the downward kinetic energy calculations
Any mass that is Ejected cannot be used to calculate downward kinetic energy for the continuation of the pancake collapse theory.
Unfortunately for you, buildings are made to support the mass that is above them, not to crumple under the load of the floors above them.
And the floor that supports that floor, and the floor that supports that floor, and the floor that supports that floor, and so on and so forth.
Your continued assertion that each individual floor was just floating happily in air until the floor above fell on it is preposterous,
Originally posted by ErtaiNaGia
Considering that most of the building was empty, and had no tenants, I'd say not much.
Wrong, the Kinetic Energy is transferred to the MASS of the floor below, which subtracts from the kinetic energy of the falling mass above.
As the energy is transferred to the stationary floor, the energy is distributed to the support structures, and their connections,
including the floors and structural supports farther below.
Originally posted by ANOK
One of things they keep refusing to address is the fact that Ke is lost when objects collide.
They seem to think energy has it's own power, and is not simply a measurement of work done.
Another is that the forces on each colliding object is the same. regardless of mass or velocity. They seem to think the falling floors would all stay intact while causing the lower floors to be destroyed.
They also fail to realise that it would take more energy to cause the connections to fail than the concrete itself, so if the connections failed, as they claim, then there is no reason the floors themselves would stay in one piece and not be crushed and ejected horizontally.
I've been over and over with them on this, and they still ignore it.
Originally posted by ErtaiNaGia
Considering that most of the building was empty, and had no tenants, I'd say not much.
So, it is YOU who are wrong.
Also unique to the engineering design were its core and elevator system. The twin towers were the first super tall buildings designed without any masonry. Worried that the intense air pressure created by the buildings’ high speed elevators might buckle conventional shafts, engineers designed a solution using a drywall system fixed to the reinforced steel core. For the elevators, to serve 110 stories with a traditional configuration would have required half the area of the lower stories be used for shaft ways. Otis Elevators developed an express and local system, whereby passengers would change at "sky lobbies" on the 44th and 78th floors, halving the number of shaft ways.
Vertical shafts surrounding stairs, mechanical shafts (carrying supply and return air), elevator hoistways, and utility shafts were all contained within the building core, and were enclosed by gypsum planking similar to fire separations commonly used today in single-family attached housing. While similar to other gypsum shaft wall systems and firewalls, this system was unique and innovative in that it eliminated the need for any framing. The gypsum planks were solid 2 in. thick (2.5 in. on floors with 16 ft ceiling heights) and 16 in. wide, with metal tongue or groove channels attached to the long sides that served as wall studs.
Originally posted by ErtaiNaGia
And each of those connections requires a certain amount of Kinetic energy to fail, and that is kinetic energy that is subtracted from the total Kinetic energy of the falling floors.