Fire resistance of earthquake damaged reinforced concrete columns

The post-earthquake fire (PEF) phenomenon occasionally causes more severe damage than the earthquake itself. In order to investigate the fire-resistance performance of concrete columns, the earthquake damage of concrete structure are defined into three types: cracks, spalling, and residual deformation by earthquake disaster data and seismic experiments. Next, earthquake-damaged models of RC columns are established based on these geometric characteristic parameters. Full-scale earthquake damaged column tests are performed to analyse the failure mode of components under high temperatures. The effects of the geometric characteristic parameters and mechanical performance parameters on the fire resistance of earthquake-damaged RC columns are calculated by ABAQUS. Finally, the damage reduction factors of PEF RC columns are used to evaluate the degradation of fire resistance. The quantitative relationships between PEF RC columns and undamaged columns are established based on the reduction factors. These relationships can provide a rapid assessment of the fire resistance and bearing capacity of earthquake-damaged structures.