THANKYOU..
you gotta remember though..most here have NOT taken past high skool physics..
most failed that 2..
Perhaps... Steel ratings also determine how much heat, and how LONG... that's what people often forget... Yes, steel may have a temperature tolerence of let's say 2000 degrees... which is about what I believe it was in this instance (or somewhat close), but that tolerance is based on how LONG it can withstand that heat as well.
As with any physical body, heat must be passed into the material and from there, via conduction, it moves throughout the material... It is not an "instant" process... and once it has been conducted... there is still an amount of time that the steel is structurally sound.
It doesn't jive with physics at all.
Had a single section of the building lost it's tolerance, you would have seen one section of the building start to fall before the others... The area which had been degredated would have started the process and would be quite noticable.