Direct evaluation of boundary stresses in the 3D BEM of elastostatics

In this paper, a method for the evaluation of boundary stresses directly from the BEM solution of elasto-static problems using the static boundary integral equation is presented. The technique is valid for corners and edges as well as smooth points on the boundary, and involves defining a new interpolation function for continuous elements which incorporate certain continuity conditions arising from the hypersingular nature of the integrals involved. An integration technique based on the singularity subtraction method using series expansions is adopted for the hypersingular intergrals. Results are shown to be more accurate than those obtained with conventional techniques.