Abstract: In order to study distribution of welding temperature field of T-joint of girder with corrugated steel web, based on thermo-elastic-plastic theory and finite element theory, temperature field of T-shaped joint by CO2 shielded arc welding was simulated and verified by experiments at 20 ℃ with Simufact Welding software, double ellipsoid heat source model and configuring the relevant parameters.Influence of different ambient temperature on cooling rate of molten pool was analyzed.The results showed that type of heat source and the related parameters used in the simulation were reasonable, welding heat input was sufficient, welding penetration was moderate, and bottom plate and web were connected well.Distribution of heat-affected zone of weldment obtained by simulation was an irregular closed ellipse and showing a certain temperature gradient, which was in good agreement with the test results.During the welding simulation process, temperature of the weld reached melting point of material 1 500 ℃.The isotherms presented dense in front of the heat source and sparse in the rear with a certain gradient, which was similar to heat transfer in the actual welding process.In the post-weld cooling process, temperature of the weld and its near area dropped promptly, temperature gradient fell apace, and radiation range of temperature field increased constantly.Cooling rate of metal molten pool was inversely proportional to ambient temperature.The research results obtained in this paper could provide reference for the analysis of welding temperature field of similar bridges.