Temperature-dependent properties of high-strength steel for evaluating the fire resistance of structures

In recent years, high-strength steel (HSS) is finding increasing applications in building construction due to its excellent strength and durability properties. However, structures, incorporating HSS, exhibit lower fire resistance due to rapid deterioration of their mechanical properties at elevated temperatures. For evaluating the fire resistance of steel structures, high-temperature properties of steel are to be specified as input data. The properties of steel not only vary with temperature but also the extent of variation is influenced by the type and grade of steel. This paper presents a state-of-the-art review on temperature-dependent properties of HSS. The available data and relations for thermal, mechanical, and deformation properties of HSS are compiled. Using these data, the variations in the elevated properties of HSS are established and the reasoning for such variation is explained. Finally, the critical properties to be considered for evaluating the fire resistance of structures, incorporating HSS, are discussed.