Direct Calculation of Free Term Coefficients in Displacement Boundary Integral Equations for 3-D Isotropic Problems

Direct calculation of free term coefficients for linear isotropic problems in three dimensional displacement boundary integral equations is presented in details. In addition, the shape functions of 9 node non-continuous and semi-continuous elements for modeling the crack surfaces, layers interface, infinite boundary and other similar problems have been demonstrated. This proposed method for calculating cij coefficients has been verified comparing with some solved problems.