A SPECIAL BOUNDARY-ELEMENT FOR THE PROBLEMS OF MULTI-HOLES, CRACKS AND INCLUSIONS

By combining the fundamental solutions, the method of boundary element and the technique of subregion, the problems of multi-holes, cracks and inclusions are solved efficiently and accurately in this paper. The stress concentration induced by the existence of holes, cracks and inclusions, and the interactions among them are also discussed. Moreover, examples are given for the calculation of effective moduli of fiber-reinforced composites by treating the fibers as inclusions. It should be noted that since the fundamental solutions used in this paper have satisfied the boundary conditions for the hole, crack and inclusion as a priori, it is unnecessary to discretize the hole (or crack, inclusion) boundary. Thus, a vast amount of computer time and storage in numerical calculation can be saved. However, due to the boundary effect, the efficiency of the present method will be degraded when the distance among the inclusions, holes and cracks is too close.