Because of the complicities in the detailed structures and the mechanical behaviours

it is difficult to completely simulate the bolted discontinuous rock with the conventional numerical model. Based on the former works of the authors

the composite element method (CEM) is further developed to study bolted discontinuous rock. The mesh can be generated without taking account of the existence of bolts and discontinuities in this study. The composite elements of bolted rock

discontinuous rock and bolted discontinuous rock can be defined and their CEM model can be formulated respectively. Some sub-elements covering the different materials are also defined to simulate the detailed structures in bolted discontinuous rock. The algorithm of bolted discontinuous rock by composite element method is illustrated and the way to implement this algorithm is introduced. The comparison of the numerical examples between FEM and CEM shows the robustness of the proposed method

and the advantage of CEM over

i.e. very convenient for the pre-process.