ABSTRACT
This paper investigates the post-fire compressive behavior of thin-walled cold-formed Ultra-High Strength Steel (UHSS) tubular stub columns. The nominal 0.2% proof strength of the UHSS used in this study at room temperature is 1200 MPa. UHSS stub columns with length to diameter ratio (L/D) of 3 are axially compressed after being cooled from different fire temperatures to room temperature. The measured temperatures across the column height during heat-up and cooling phases, the stress-strain curves of the tested columns along with those obtained from the tensile coupon tests, residual strength values, slenderness values, and energy absorption of the tested specimens are all discussed for different fire temperatures.
