Asymptotic analysis of stress singularities in composite laminates by the boundary finite element method

The present contribution contains asymptotic studies of stress singularities which occur in the vicinity of interfaces at straight free edges and also at free corners of composite laminates where two straight free edges intersect. The computations are performed by the boundary finite element method (BFEM) which only requires a boundary discretization and which in essence is a boundary element method solely relying on standard finite element formulations. The BFEM does not require the knowledge of a fundamental solution and reduces the spatial dimension of the discretizational effort by one. Anisotropic material behaviour is incorporated without difficulties. As the BFEM requires certain similarity or scaling properties of the given structural situation and involves the closed-form solution of a system of differential equations for the displacement components with respect to the scaling direction, it can also be characterized as a hybrid or semi-analytical method.