Impact and post-impact behaviours of steel-reinforced concrete-filled steel tubular columns after exposure to fire

Abstract

This paper presents a numerical investigation on the lateral impact and post-impact behaviours of steel-reinforced concrete-filled steel tubular (SRCFST) columns after exposure to fire. The finite element analysis (FEA) model of post-fire SRCFST columns under lateral impact is developed by the ABAQUS software and calibrated. The impact responses of post-fire columns are analyzed, namely the impact process, the development of internal force, the energy change and plastic damage, etc. The impact resistance of SRCFST and CFST columns after fire is further compared, and the residual capacity of post-fire columns after lateral impact is studied. The results show that the SRCFST column after fire exhibits excellent impact performance, and the influence of fire degree on the impact resistance degradation of SRCFST columns is significantly smaller than that of CFST columns. A parametric study is also carried out to analyze the influence of various parameters on impact responses of post-fire SRCFST columns, and simplified methods are finally proposed to evaluate the impact resistance and residual capacity of post-fire SRCFST columns under lateral impact.