Mechanical properties of E350 steel during heating and cooling

摘要

This paper investigates the mechanical properties, namely yield strength (sigma(0.2,T)), ultimate strength (sigma(u,T)) and elastic modulus (E-T) of mild steel E350 (equivalent to S355JR in EN 10025) subjected to growth, cooling and post-fire phases in a non-standard fire condition. Based on the combined results from the present study and those from the literature, reduction factors for yield strength, ultimate strength and elastic modulus have been proposed, for growth, cooling and post-fire phases. In comparison to the growth phase, the rate of regain of the yield strength and elastic modulus are found to be relatively slower in the case of cooling phase. Additionally, in general, it has been seen that, the mechanical properties have been able to regain as they cool down after being heated to temperatures lesser than 600 degrees C. Further, stress strain models corresponding to a) growth and cooling phases; and b) ambient temperature and post fire phase have been proposed.