A thermo-mechanical analysis of stainless steel structures in fire

A novel multi-dimensional combined isotropic-kinematic plasticity material model was recently developed by the authors for thermo-mechanical analysis of steels at elevated temperatures. In this paper, the capability of the new material model was further validated for transient loading conditions during heating and cooling using recent experimental data. The multi-dimensional material model was adapted to a 1D J2 plasticity model and implemented in the open source software OpenSEES for studying the structural performance of stainless steel beam and frame structures in fire using finite element analysis (FEA). This paper presents the findings of the studies, with a focus on the behavioural comparisons between the carbon steel and the stainless steel structures. Using the FEA method, the studies provided results that filled the research gap in understanding the global structural fire performance of stainless steel structural systems. The significant impact of stainless steels' high material non-linearity and high thermal expansion on their structural fire performance is highlighted.