Finite Element Analysis on Temperature Field and Residual Stress of Welding Assembly for I-Beam and End-plate

摘要

The welding assembly of I-beam and end-plate is a common structural node of steel structures, but study on welding residual stress for this welding assembly is limited. In this paper, based on full scale model of welding assembly for I-beam and end-plate with medium plate, three-dimensional finite element model was created, and ANSYS parametric design language (APDL) was used to write computer program for numerical simulation of welding temperature field and residual stress, birth-death element technique was used to simulate weld deposition and the moving heat source. And the infrared thermometers were employed to measure the real-time temperature of the welding seams during welding and cooling process for verification purposes. Results show that the measured thermal cycle curves match well with the simulation results, prove that the heat source model and mesh generation method used in this paper are reliable, thus lay a good foundation for the next step of residual stress calculation. Simulation results of welding residual stress indicate that the longitudinal and transverse stress are main residual stresses on the surface of the end-plate; transverse stress on the surface of the web and flange plates is relatively lower; high tensile stresses exist in the central zone of upper weld toe on the flange plate and near the weld of flange plate. Simulation results also indicate that welding temperature field and residual stress of large-scale structures can be calculated simultaneously without considering the mutual influence to save computing time when the distance between welding seams is relatively far.