Q. Huang et Ta. Cruse, ON THE NONSINGULAR TRACTION-BIE IN ELASTICITY, International journal for numerical methods in engineering, 37(12), 1994, pp. 2041-2072
The work reported herein develops a generalized traction-BIE formulati
on which involves only weakly singular integrals (in the three-dimensi
onal problem) or totally regular integrals (in the two-dimensional pro
blem). The first step deals with the terms in the Somigliana displacem
ent identity, and then the derivatives of these terms. The only condit
ions required for the existence of the traction-BIE and the related So
migliana stress identity are weak continuity of the in-plane derivativ
es of the surface displacements and of the surface tractions. It is sh
own that the Cauchy Principal Value (CPV) interpretations so commonly
used in BIE developments are unnecessary. The formulation is establish
ed not only at a smooth boundary point, but also at a corner point. Th
e extension of the non-singular formulation to discontinuous boundary
tractions and tangential derivatives of the boundary displacements app
licable to a generalized problem statement as well as the usual BEM im
plementations is also shown. In the demonstrated formulation, the sour
ce points are located directly at the boundary nodes and non-conformal
elements are not needed.