Boundary elements and damage mechanics to analyze excavations in rock mass

This paper presents and discusses a nonlinear model based on damage mechanics theory, together with the boundary element method. The mechanical model proposed, as well as the computational tool developed in this research, have proved to be very efficient and simple, providing reliable information on the deformation and stresses in the rock mass. The model estimates the behavior of the damaged rock mass undergoing an excavation process, by assuming a nonlinear, heterogeneous and anisotropic medium. An isotropic model of damage is used, combined with a load relaxation process at the excavation wall, which is discretized via two-noded linear boundary elements. The computational approach is also described. Three illustrative examples which show the power, simplicity and versatility of the proposed approach are included and discussed in detail. (C) 1997 Elsevier Science Ltd.