Abstract: Based on software ABAQUS,a user material model and subroutine for the analysis of reinforced concrete frame structures in a fire were developed to simulate the cross-section temperature field of reinforced concrete components more accurately.With the incremental theory of plasticity,the non-linear analysis of a reinforced concrete frame model subjected to a dead load and a local fire at different conditions were carried out.Based on the non-linear analysis results,the distribution of plastic hinges and the damage mechanism of the reinforced concrete frame in a fire were revealed,and the effects of fire room location on the failure mechanism of reinforced concrete frames were discussed.In the end,the most dangerous location of fire room was explored.The analysis results indicate that the reinforced concrete frame members undergo internal force redistribution under a fire,and the superposition of constraint internal forces with external loads causes plastic hinges in beams and columns.In addition,the distribution of plastic hinges and the damage mechanism of reinforced concrete frames are affected obviously by fire room location,so the disadvantage of fire room location should be considered in a fire resistant design.