A CONTOUR INTEGRAL FOR 3-DIMENSIONAL CRACK ELASTOSTATIC ANALYSIS

A contour integral method for calculating stress intensity factors has been successfully applied to two-dimensional crack problems for both static and dynamic cases. In this paper the method is extended to thre e-dimensional static problems. By means of the displacement discontinu ity method and the technique of variation of crack area, the required derivatives of traction and displacement for a reference problem are d etermined. The stress intensity factors are calculated by a contour in tegral with a non-singular integrand. The only absolute values of trac tion and displacement that are required for the real problem are on co ntours away from the crack-tip; they are determined by the dual bounda ry element method. For mixed-mode problems, the ratios of stress inten sity factors are determined by the ratios of the mixed-mode discontinu ity displacements near the crack front, all stress intensity factors c an be calculated from only one reference solution. (C) 1997 Elsevier S cience Ltd.