Originally Posted by
DGM
What makes you think it wouldn't. It had all day to do the job.
Because it never happened before. Structural steel in high rises is massive and takes a significant amount of heat and time to weaken. There usually isn't enough fuel in a given area of an office fire to heat the large pieces of steel in that area enough to cause weakening to the point of failure. That is most likely why it hasn't happened before.
The fires in WTC 7 did not burn all day in a specific area. They burned out when the fuel was used up in a specific area and there are photos of plenty of burned out areas and no hint of a collapse. Not surprising as this was the norm.