Abstract: The finite element software ABAQUS was used to establish the temperature field model and the thermo- mechanical coupling model of the four- sided fired timber beams. The temperature distribution, carbonization rate and residual bearing capacity of the fire were analyzed and compared with the test. The results showed that the temperature field model of the timber beam simulates the arc at the corner; the average carbonization rate in the horizontal direction is 0.87 mm/min under four sides, and the average carbonization rate in the vertical direction is 0.86 mm/min; the water content has little effect on the carbonization depth; the fire time of the wooden beam has a great influence on the residual bearing capacity after the fire.

Key words: timber beams;temperature field, residual bearing capacity, finite element analysis