800°C if im not mistaken, meaning steel doesnt lose its structural capacity up to that range. knowing how these codes are written, i bet it wouldnt turn into slush at 801°C.

I didn't think I'd even have to mention that the jet fuel lit massive amounts of plastic, cloth and wood on fire. Come on. And yes steel does lose strength at 800c. Look it up

"the entire strength of the structure was on the outer edge" is plain wrong.

"entire strength" yeah whatever, hyperbole- I know it had a core. Half of the strength. Half of the strength, as opposed to the normal amount supported by the exterior walls in skyscrapers, which is extremely little. That is why it fell like an eggshell. They had huge open areas to make the offices more comfortable, and they made that possible by placing shitloads of the support structure on the exterior wall.

but i cannot accept that they caused the collapse, my professional integrity does not let me.

(and a civil engineer).

Don't you design culverts?