Stress singularity analysis around the singular point on the stress singularity line in three-dimensional joints

The characteristics of the stress fields around a singular point on the stress singularity line of dissimilar materials in three-dimensional joints are investigated using BEM. Contour for the order of stress singularity around the point is mapped on Dundurs’ parameters plane using eigen value analysis by FEM. The results in 3D joints are compared with those in 2D joints having the same cross section and material combination. The order of stress singularity around the singular point on the stress singularity line in 3D joints is almost identical with that in 2D joints in the singularity region. However, the zero boundary of singularity in 3D joints is slightly different from that in 2D joints. Furthermore, the multiple root of p = 1 exists in the eigen value analysis by FEM. Therefore, logarithmic singularity possibly occurs around the singular point on the stress singularity line. Then, the stress distributions around this point are expressed by the combination of the r^λ term and logarithmic singularity terms. Finally, the characteristics of the stress intensity factors of the r^λ term and logarithmic singularity terms around the singular points are investigated.