Extra-thick Plates Multi-channel Butt Welded Temperature And Stress Dynamic Simulation Analysis

With the steel structure and technological development, thick and extra-thick steel plate in the bridge project and other large-scale structure are applied more and more widely. Although thick steel components stiffness, but the welding residual stress concentration, and sometimes more than the yield strength, affect their performance. Based on the Yangtze River in Chongqing Guanyinyan Jiangjin Bridge welding test background for the subject, using finite element analysis software ANSYS simulation.Welding process to impose partial compliance in time concentrated heat input, will form part of welding melting, this is precisely what has caused welding residual stress and deformation of the root causes of welding. Metallic materials in the heat spread very fast, welding must be highly concentrated heat, the temperature welding field is very uneven and unstable. The use of energy conservation derived temperature conduction of the calculus formula, in accordance with the welding process differential equations determine limitations and restrictions of the boundary conditions, the use of variational principle derived temperature field of finite element formula.Occurring at the root welding seam on stress, the value of some over Weld yield stress, in the course of the analysis of the structure of materials in the use of plastic deformation hardening Following strengthen theoretical model, a simplified approximation of Bauschinger effect. Welding temperature field is changing with time, welding residual stress also synchronized with temperature changes, that is, the temperature field caused by welding residual stress belonging to the non-conservative force system. But Weld in the plastic deformation depends not only on its final state by force, but the loading path (the multi-channel welding and welding seam in the order of the deformation path), in the elastic-plastic constitutive theory analysis Only by incremental form of the theory can be set up to track the loading path. Thermal and structural analysis of the coupling effect will be as inertial load temperature, according to elastic-plastic thermal instability dynamics of the temperature field.In this paper, the mock target thickness of 80 mm for special welding steel plate, welding method for X-groove butt welding, of the material is Q370QE. In welding using ANSYS software model finite element modeling, in accordance with the welding process sequence, through heart-shaped unit coordinates comparison unit from the weld, using ANSYS simulation technology weld cell death filled the dynamic and therefore the analysis of the model, plus set for a long time and nonlinear, thermal analysis therefore be carried out, then the structure of its units into units of the thermal load as a structural analysis of the structure by adding to the completion of the thermal and structural analysis of coupling.The post-processor using ANSYS mapping function in the process of the welding residual stress map, drawn by the welding residual stress analysis of simulation results and the Yangtze River Bridge Guanyinyan welding test results match, validation error in the simulation of welding residual stress measurement instruments The error, but there are some error.