In order to study systematically the fire resistance of concrete-filled steel tubular（CFST）structure

this paper presents a finite element model of concrete-filled square hollow section columns exposed to three-surface fire based on ABAQUS.The reasonable thermal and material models of steel and core concrete are used in the FE model.The FE model is developed to study the mechanical performance of CFST columns exposed to overall stage fire

including loading at ambient

heating

cooling and post-fire.The FE model is verified by the others′experimental results.The parametric analysis of FE model is performed

such as fire load ratio of column

depth of fire protection

slenderness ratio of column and fire time ratio of column.The results show that the failure modes in non-uniform fire conditions are different from the uniform fire conditions due to the additional eccentricity.The ultimate bearing capacity and initial stiffness of the CFST columns are reduced due to the high temperature.The fire time ratio of column and slenderness ratio of column have significant effects on the mechanical performance of CFST columns exposed to three surface fire.