Originally Posted by LTC8K6
This is true.
At 600 degrees F, steel (generally) retains 95% of its room temperature ultimate strength. At 800 degrees, its at 88%, 1000 degrees, 58%, and at 1200 degrees, you're down to 37% of Ultimate
(breaking) strength after 1/2 hour exposure.
Yield strengths are even lower--and once you start bending (or buckling, which in this case is the more likely scenario), things progress rapidly, since the geometry of the collumns is a large portion of their strength. Distort the geometry, and destroy the strength.