Experimental studies on mechanical properties of S700 MC steel at elevated temperatures

At elevated temperatures, the mechanical properties of high strength steel (HSS) reported in the literature have an observable scatter. They differ from design code values that are mainly based on experiments on mild steel. In this paper, the mechanical properties of S700 MC at elevated temperatures were investigated with steady state and transient state tensile tests. The reduction factors of yield strength started to decrease from 100 °C onwards, while the EN 1993-1-2 values have no decrease up to 400 °C. The reduction factors of proportional limit were below the code values up to 200 °C. The modulus of elasticity was consistent when using both monotonic and repeated loading but differed from the code values. Further comparisons of the mechanical properties of steels with the same strength grade with the values in the literature confirm the importance of testing HSSs produced with different manufacturing processes. The constitutive equations and representative material models proposed for S700 MC also support the implementation of a performance-based approach to structural fire safety design.