.. the falling section of the tower would be crushed itself along with the floors it is crushing below it, meaning that if the building was structurally equivalent (it was not, the building is build progressively stronger as you travel down the building) it would crush the top 12 floors at the same time as it collapsed the 12 floors beneath it, leaving nothing solid to act as a "pile driver" to crush the remaining floors below it.
This is not true. When the top section moves as one piece down just one floor, it is acting as a dynamic, not a static load. As one moving section, it's internal stresses balance each other out.
Yes the floors were progressively stronger as you go down. But that's nothing compared to the momentum from above.
Here is a simple example. A bowling ball weighs 10 lb, and rolls off a table 48" high onto your foot. Once it hits your foot it dissipates it's energy in 0.25 inches. The force on your foot is -
F = 48/.25 * 10 = 1920 pounds. Your foot is crushed.
Once the pile driver effect starts it can't be stopped.
We aren't talking about bowling balls and feet. Again we are talking about the
LAWS of physics. If the force is sufficient enough to crush the progressively stronger floors below it, it is strong enough to crush the "pile driver" at minimum in the equivalent amount of time as it crushes the floors below, eventually leaving crushed debris as the only remaining downward force. As a result this means that the "pile driver" effect is dissipated with every floor it crushes below it because it does not act with a unified downward force and falls to the side or is otherwise dissipated interacting with itself. Every action has an equal and opposite reaction. Again you are just denying the laws of physics while providing no actual reasoning, just providing sad examples of bowling balls and feet while you play word gymnastics to try to make it sound like you have some logic behind your point. Physics trumps word gymnastics.
....
Says
FUCKING PHYSICS. Gravity doesn't pull 4-ton beams 600 feet sideways, .....
Try doing the calculation for the energy required yourself:
http://www.1728.org/energy.htmUsing the MINIMUM meters per second velocity assuming the beam came directly from the impact zone, 21 m/s, and the mass of the girder at 4 tons, the required force is equivalent to
2.1e-4 TONS of TNT! That is the MINIMUM VALUES. If the beam came from the middle of the building, at 30 m/s, the required force would be
4.3e-4 TONS of TNT. Tell me some more about how explosive force is not required......
That's 4.3 x 0.0001 x 2000 lb/ton = 8.6 lb of explosive (EQUAL TO 40,000 joules).
But PE = mgh, mass gravity height,
E= 8000 lb * 32 ft/sec^2 * 1000 = 2.4 * 10^7 joules.
40,000 joules from your explosives
24,000,000 joules of PE, potential energy
So again, isn't the PE explanation a SUFFICIENT one?
Why is the explosives explanation a NECESSARY one?
As you can see, there are trying enormous amounts of energy in a tall building's collapse. A cartwheeling 40' section of an I beam certainly can deflect a 4 ton section of an I beam hundreds of feet sideways. Or it slides sideways on a rubble heap. Or a section of the perimeter columns tilts over like on a pivot (which IS SEEN in the video) and imparts energy.
There are several problems with your logic. First of all you are taking the entire energy force of the building (I assume, you still haven't explained where you get your numbers from), and claiming all of it is available to some how fling these multi-ton objects laterally. The calculation I provided was for ONE single 4-ton girder, and you are attempting to use the entire crushing force of the building as an energy source in comparison claiming it is not very much. Multiplied thousands of times to account for the fact that this force does not just act on one single girder, your comparison dwindles. Additionally the buildings were not a perfectly engineered projectile launcher, it was an open space with giant gaps for air pressure to flow out of, meaning that this force had to be MUCH larger in order to act with such pressure against the fact that there was not an airtight seal acting only upon a single girder. Your argument reminds be a lot of gun control freaks who try to compare US and UK gun crimes stats without correcting for population and claiming this is a valid comparison.
The second gaping hole in your logic, is that all of that energy is directed DOWNWARDS by gravity, not laterally. The rubble heap was not tall enough to account for your "sliding" theory, and even if the girder was "cartwheeling", a massive force still had to act upon it to send it flying. Describing a different type of movement of the object does not explain away the amounts of energy required to send it on this path. Again, Newtons 3rd law states every action has an equal and opposite reaction, hence that free falling "cartweeling 40' section" would absorb the impact of the 4-ton girder, it does not account for some "unexplained" propelling force away from it, it is not attached to anything providing sufficient resistance or force to make it magically fly laterally. Even if by some miracle this were true, you still need to account for the massive lateral force provided by that 40" section, which would require EVEN MORE lateral force! In effect you are arguing against your own point. Again your argument has no substance, it basically just consists of deny deny deny, and hey look over here!