Fatigue strength evaluation method for load-carrying fillet welded cruciform joints

In order to make clear the fatigue strength evaluation method for load-carrying fillet welded joints failing from weld roots, fatigue tests on the joints with fillet welds of various shapes (isosceles triangle, two types of scalene triangle, concave, convex) have been carried out. Fatigue crack propagation analyses have been also performed for the tested joints and one hundred models of the joint. On the basis of experimental and analytical results, the influence of weld shape, weld size, weld penetration and plate thickness on the fatigue strength are made clear, and then, a numerical expression of weld throat is proposed for evaluating the fatigue strength.