Efficient Coupling Of BEM And FEM InGeomechanics

For the structural analysis of excavations in rock, numerical investigations of complex three-dimensional structures are required. By combining the Finite-Element-Method (FEM) and the Boundary-Element-Method (BEM) it is possible to consider the nonlinear behavior close to the cavities and the influence of the surrounding rock mass. For the blocked and unsymmetrical large system of equations an equation solver is presented, developed in cooperation with the "IBM Scientific Center Heidelberg". Based on Grotty's solver, the algorithm ignores many of the zero-blocks. An important advantage is the possibility of storing nonzero-blocks in Full Matrix Storage Mode, Compress-Matrix Storage Mode or Profile-In Skyline Storage Mode. In addition, all algorithms were transformed into BLAS 3-Standard. As a consequence, required computational time and storages are efficiently reduced.