Blithering nonsense.
There's no structure in the building that could have stopped the collapse once it began. The building transfered gravity load AROUND the floors through perfectly aligned vertical columns shunting that load into bedrock.
When the floors began impacting, it was floor to floor and utterly haphazard. You had structural steel colliding with floor trusses designed to support their own weight and that of say, people and desks. Not the gravity loads of dozens of stories of falling structural steel. They would have collapsed almost instantly.
Then there's GRAVITY, accelerating the debris field of dozens of floors of structural steel before they impact with the floor below. Radically increasing the forces each floor was subject to with the debris field. An increase that would have kept on increasing as the debris field accelerated.
Worse still, there's impulse....the performance of a material under quick sudden forces rather than measured, consistent forces. Structural steel has a MUCH lower load bearing capacity when subject to sudden forces than it does consistent ones. About a third less. And dozens of stories of falling structural steel accelerated by gravity are both powerful and sudden.
Finally, each floor that collapsed ADDED mass to the debris field. So you have MORE mass, MORE acceleration under gravity....while each floor truss had a static amount of resistence it could offer, which was utterly insuffecient for even ONE floor collapsing on top of it, let alone dozens, let alone dozens accelerated by gravity.
Once the first floor fell, there's literally nothing that could have stopped the collapse all the way to the ground. Instead, the collapse would have accelerated under gravity, adding more mass with each floor until it finally stopped when it collided with the ground.
Which is exactly what we saw.
While it is probable the collapse was the natural result of the fires, you still have lots of things wrong.
An impulse, quick sudden force, is not more damaging then a slow and steady force of equal value.
And the collapsing floors do NOT add more weight, as the first falling material picks up getter velocity than the stuff that fell later. Falling material is essentially weightless in relation to each other.
And there was not supposed to be any significant fire.
The jet fuel could not have been retained, as it all blew out the other side of the building, and instantly flashed.
There is not supposed to be any significant combustible in any high rise.
And again, buildings were promised to be plane proof.
After the 1945 B-25 hitting the Empire State building, that accidental potential was written into the building codes.
{...
On July 28, 1945, a B-25 Mitchell bomber of the United States Army Air Forces crashed into the Empire State Building in New York City, while flying in thick fog. The accident caused the death of fourteen people and damage estimated at US$1 million, although the building's structural integrity was not compromised.
...}
So according to the experts, no building was supposed to collapse.
