RESEARCH ON THE STRENGTH EVALUATION METHOD OF FILLET WELD BASED ON FLOW STRESSES

CHEN MingYa; ZHAO WanXiang; GAO HongBo; ZHOU Shuai; LIN Lei; PENG QunJia; SHI FangJie; YU WeiWei

doi:10.16579/j.issn.1001.9669.2024.06.009

Abstract：Due to the simple construction,fillet welds are often widely used in the connection of metal components.However,the non-self-balancing welding residual stress in the fillet weld is obvious,and the existing evaluation codes and standards still lack a clear stress checking method.In the assessment codes such as Code for design of steel structures,the influence of bending moment load and welding residual stress of fillet weld isn't considered in the given strength calculation criterion,which limits the application range of related methods.Based on the experimental test and theoretical research on the strength of fillet weld joints,a method of strength evaluation based on the flow stress of weld material was proposed.The strength experiment results of fillet weld connectors show that the weld strength corresponding to the maximum tensile load is very close to the mean value of the difference between the tensile and yield strength of the experimental test.It can be considered that the welding residual stress in the fillet weld is close to the yield stress,and the failure occurs when the stress in the fillet weld increases to the tensile strength during the loading process.Under pure shear condition,the maximum load of fillet weld connector is close to the value under tensile load.Under the condition of considering the welding residual stress of fillet weld material,the material evaluation coefficient of fillet weld evaluation criterion based on flow stress is set to be 0.8,and the evaluation criterion of fillet weld connector under tensile and bending moment load is also indirect given.