If we're talking about the Twin Towers, failure in compressive shear results in a plane surface separation at 45 degrees to the applied load. (It maximizes at the product of the sine and cosine of the angle between stress and column axis.) Evidence for collapse by rapid shear failure of the supporting columns.
Building didn't have explosives in them.
The steel beams were cut in clean, 45-degree angles.
They were all over the area after the collapse.
That's why they were shipped off to China before a real investigation could take place.
If we're talking about the Twin Towers, failure in compressive shear results in a plane surface separation at 45 degrees to the applied load. (It maximizes at the product of the sine and cosine of the angle between stress and column axis.) Evidence for collapse by rapid shear failure of the supporting columns.