3-DIMENSIONAL STRESS SINGULARITIES IN ANISOTROPIC MATERIALS AND COMPOSITES

A general numerical procedure is presented for determining the 3-dimensional stress singularities in anisotropic materials and composites. The geometry near the singular point can be represented by a conical wedge whose lateral surface is generated by straight lines passing through the wedge apex. The cross section S//1 of the conical wedge at any constant radial distance from the apex defines the geometry of the 3-dimensional singular point in the material. If S//1 consists of two or more regions each occupied by a different material, we have a 3-dimensional composite conical wedge. A 2-dimensional finite element scheme based on a variational principle is developed to find the order of stress singularities at the wedge apex. The method can be applied to any shape of S//1.