Mechanical properties of hot-rolled structural steels at elevated Temperatures：A review

Abstract

Numerous experiments have been conducted to investigate the mechanical properties of structural steels at elevated temperatures, including mild steel and high strength steel (HSS). However, material models in the current mainstream fire design standards are mainly based on results of mild steel, and hence their applicability to HSS is questionable. In this paper, test data in literatures on mechanical properties of hot-rolled carbon structural steels with strength grades from 235 MPa to 960 MPa at elevated temperatures were comprehensively summarized. The effects of steel manufacturing process, test method, heating rate, and loading rate on the performance of structural steels at elevated temperatures were analysed. It is found that for steels with all the considered grades, reduction factors of the nominal strength specified with 2.0% of strain have similar downward trends. However, downward trends of the reduction factors of Young's modulus, ultimate strength and 0.2% offset yield strength vary with the steel grade. The manufacturing process, test method, heating rate and loading rate all have certain effects on the mechanical properties of steel at elevated temperatures, but the effects on the reduction factors of strength are generally slight. Finally, recommendations on the future research were proposed.