A simple physical simulation of the WTC collapse

A conservative simulation of the WTC collapse. Indicated time is in seconds. Ejected mass is the mass that is thrown out or turned to dust in the floor-floor collisions.

Every floor has a momentum threshold. If that threshold is exceeded by the momentum of a falling floor, the wall below the stationary floor is broken and its whole mass ejected. The momentum of the whole upper part is not assumed to hit the undamaged floor because the connections between floors are assumed to be broken on impact.

The floor-floor collisions are inelastic, and 20% of the combined mass of the floors is also ejected in the collision. After collision, they become free-falling. The momentum threshold grows linearly with elevation, and it is three times larger at the bottom than at the top. The top floor can take an impact of the mass of one floor, dropped from one floor height (a conservative guess) without breaking the wall below. The mass of a floor does NOT change as a function of elevation - in reality the higher floors were not as massive as the lower ones, which would make the collapse even slower.

Parameters:
- building mass: 3E8 kg
- height 417 m
- floor count 110
- wall to floor mass ratio: 10% (a wild guess)
- floor-floor collision mass loss: 20% (conservative guess ?)
- max floor momentum threshold: Sqrt(2 x g x floorHeigh x 3) x floorMass
- time resolution: 0.01 s
- floors 79 and 80 removed at the beginning (initial free-fall: 2 x floorHeight)

Category:

News & Politics

Tags:

• wtc
• 911
• simulation
• collapse

[korayek]

YES! very simple and pointless...

[Tsutomu6]

@roquefortfiles

Math? What math? I thought math is about calculating. And 180kt "in motion" is not a momentum. There are variables you have to define first.

Your equasion probably looks like "pretty big" > "pretty small". And you call that math? I call that stupid.

And many ppl have done simulations in your favor. 0% mass ejection and instant bolt failure that doesn't absorb any energy. You still won't be able to get the destruction done in the observed time.

[roquefortfiles]

Riiiiiiight!! and one floor is going hold or contain 30 stories moving as one unit? Not possible. Not even REMOTELY possible. You are asking floor connections of 3/4 inch bolts and 5/8th's bolts securing the floor trusses directly below the failure point to hold 180,000 tons in motion? When the floor has a load limit of about 1500 tons??

Good fucking luck!! And it has NOTHING to do with George Bush. Numbers and math don't lie.

Can you say INSTANT OVERLOAD? Thought you could.

[Super911truth]

Question: damaged and burning tower section hits undamaged tower section. Which one is blasted into oblivion?

[fisheye441]

Nearly freefall and crushing dont work together, except more enrgy is inserted into the system.

[Skeptic121]

@dune5star Newtonian physics explains building collapses just fine; no need to invoke Einstein. Since nothing in the collapse is moving close to the speed of light, you don't even need to mention Einstein, except to be a poser. BTW, you obviously have never raced because you don't understand that "rich" refers to the mixture, not the gasoline itself. A rich mixture actually burns cooler...do you OWN a car? Of course, it was jet fuel, not gasoline. It was a "plane" not a "plain". School?

[dune5star]

@iamopinionated123 everyone who believes this garbage are all retarded. no computer simulation is going to give you a correct understanding of anything... were any of you inside watching it? there are hundreds of reasons to as why the buildings fell as they did. as an exploded plain with VERY high amounts of rich gasoline would be burning everything in there, causing weak points in the structure... im sure you have heard of Einstein? law of physics from there on out kids... Go back to school.

[1971SuperLead]

20 seconds???? lol Try under 10.

[roquefortfiles]

@iamopinionated123 No it does not!! If explosives were in the building it would be removing the resistance as the building fell. That is why they are used. Gravity pulverizes the building not explosives. The WTC is encountering a great deal of resistance because the lower floors are completely intact as the upper liberated portion hits it. The debris has no where to go but out. That is exactly what we see taking place there. A CD falls very uniformly and cleanly to its footprint.

[phlyegles43]

@maydayfire FALSE. The two collapses took between fifteen to twenty seconds. You look at the videos that dont show the complete collapse just when the collapse is masked by large buildings.