Abstract: A single layer double span reinforced concrete frame model was established. Based on the thermal performance and high temperature mechanical properties of steel and concrete materials, and using ABAQUS finite element software, the single compartment fire and multi-compartment fire were simulated. The temperature field distribution characteristics and change law of internal force and deformation of beam and column members andwhole structure were studied under different conditions. Results showed that under the two different fire cases of the single span and double span of the fire, the temperature field of the double span beam and side column under fire is the same as that of single span under fire, and the temperature distribution of the central column and the joint core area is different. The temperature of the joint core area is obviously lower than that of the surrounding beam and column. The fire mode and axial compression ratio of frame column plays a significant role in high temperature mechanics response of frame structure.

Key words: fire, finite element, reinforced concrete frame, temperature field, high temperature, mechanical property