双相型不锈钢角焊缝连接承载性能有限元分析

为研究双相型S22053不锈钢角焊缝连接的承载性能，对不锈钢母材和焊缝金属圆棒试样进行材性试验，分别获得了母材和焊缝金属材料的本构关系；对不锈钢正面和侧面角焊缝连接试件进行拉伸试验，测得试件极限承载力和焊缝变形发展情况；利用ANSYS有限元软件对不锈钢角焊缝连接试件单向拉伸试验进行了非线性有限元模拟，并将试验结果与模拟结果进行了对比。对比结果表明，考虑不锈钢母材和焊缝金属本构关系差异并使用材料真实应力-应变曲线的有限元模型能有效模拟角焊缝连接承载性能拉伸试验。最后，利用经试验验证的有限元模型对角焊缝承载力影响因素进行了参数分析，并将有限元模拟值与按照美国规范SEI/ASCE 8-02、欧洲规范EN 1993-1-4，以及中国不锈钢结构技术规程CECS 410:2015计算求得的规范设计值进行了对比，得出了承载力模拟值与各国规范设计值的比值，可为不锈钢设计规范的完善和工程应用提供参考。

FINITE ELEMENT ANALYSES OF LOADING CAPACITY OF FILLET-WELD CONNECTIONS FABRICATED FROM DUPLEX STAINLESS STEEL

In order to investigate the loading capacity of fillet-weld connections fabricated from duplex stainless steel grade S22053, material tests were conducted on round bar specimen made from the base material and the corresponding weld metal. Tensile tests were conducted on transverse fillet-weld connections and longitudinal fillet-weld connections, the ultimate load capacity of the welded connections were tested, and the deformation developments with the load increment was measured as well. The nonlinear finite element analysis of the stainless steel-weld connections subjected to uniaxial tensile forces were performed by finite element software ANSYS, and the computational results were compared with test data. The comparison indicated that the finite element model using the true stress-stain curves and considering the differences of constitutive relationship between base metal and weld metal could simulate the uniaxial tensile tests effectively. Finally, parametric analysis was carried out on parameters which could influence the bearing behavior of stainless steel-weld connections, and the simulation results were compared with the design value calculated according to European steel structures (Eurocode 3), American stainless steel code (SEI/ASCE 8-02), and Technical specification for stainless steel structures (CECS 410:2015) respectively. The ratios of simulated value to design value were obtained, so as to provide a reference for the improvement and engineering application of stainless steel design code.