Mechanical properties of cyclically-damaged structural mild steel at elevated temperatures

The mechanical response of a structural element not only depends on the inherent properties of the materials which constitute the element, but also on the history of any loads it had been previously subjected to. An important instance of this is the response of steel structures under post-earthquake fire. This research aims to investigate the potential changes that the mechanical properties of structural grade mild steel experience under such a loading sequence. The experimental results presented in this paper indicate that a prior history of cyclic loading significantly affects the proceeding ductility and strength of grade 300 steel at high temperatures. This implies that any history of cyclic loading should be included in the post-earthquake fire-resistant design of structures.