Abstract：The conventional basic function can not completely simulate the deformation pattern of bolted rock，which is complex and highly nonlinear. Subdivision of the mesh can solve the problem，but it makes the preprocess more difficult. Using hierarchical technique，hierarchical composite element method(CEM) is adopted for the rock mass reinforced by bolt. The basic idea is to extend the tolerant function by adding virtual nodes，to improve the numerical precision by using hierarchical basic function，and to analyze the composite elements under the generalized nodes. With basic function upgrading，the hierarchical composite element method can better simulate the complex characters of bolted rock in physical hypostasis，which makes calculation results be closer to the true ones with coarse mesh. The analytic process of hierarchical composite element method is explained；and the way to realize this method in bolted rock is introduced. The comparison of the calculation results with finite element method(FEM) and conventional CEM shows the robustness of the proposed method. It is proven that upgrading composite element method can improve the calculation results evidently with fewer meshes.
