Fatigue property of non-load-carrying fillet welds in cruciform joint

Based on structural stress method,fatigue property of non-load-carrying fillet welds in cruciform joint was investigated by numerical analysis and fatigue test in this paper. First,it was observed that the fatigue property of joint decreased with fillet weld size increasing according to the structural stress at weld toe section,which was also verified by fatigue test. Meanwhile,the comparison of test data and S-N curve of F class in BS 7608 standard indicated that stress modification was necessary for fatigue evaluation. Then,the structural stresses of joint were calculated by finite element models including root gap and penetration respectively,and the results indicated that the two details only affected the fatigue property of joint slightly. By comparing with load carrying fillet weld joint,it was verified that the impact on fatigue property of details was dominated by force status. When defining quality levels for imperfection of weld,an appropriate criteria should be set by considering the force status of joint to reduce the manufacturing costs of structures.