Weighted traction boundary element methods for strength analysis of bi-materials

A boundary element method is developed to evaluate generalized stress intensity factors (GSIF) for non-smooth linear elastostatic problems. In the present paper, we focus on determining GSIF for bi-material interfaces. The new formulation, which is implicitly based upon the theory of boundary eigensolutions, employs displacements and weighted tractions as primary variables. Consequently, the solution is obtained exclusively in terms of bounded quantities enabling the attainment of mesh-independent results, while requiring only surface discretization. In particular, accurate values for the GSIF can be obtained directly from the nodal values of the weighted tractions, without the need for any post-processsing operations. As an illustration of the methodology, a strength analysis of an epoxy-steel cyUndrical butt joint is examined.