Large Jointed Rock Caverns In The Groundwater Under The Action Of Surrounding Rock Stability Analysis

The fractured rock is a type of complex rocks which are often met among slopes, underground powers, the foundation of dams etc.. They which include the strength, the deformation and the penetrability of the fractured rock influence the design and construction of all kinds of engineering directly. So it is given attention by circles of theory and the practice always.Based on the underground structure scheme of a large cavern group of Ertan project, the author analyses the factors how to effect the displacements of the cavern wall and also analyses the influence of the deformation of the main cavern when there is a seepage field.First , according to considerable factors of the stability of opening group(E,E,h , λ ,B), lots of working conditions of numerical simulation have been conducted under the condition of the rock without joints and seepage fields. In the study of opening group stability, the analysis is conducted mainly on the plastic zones of the side wall or surrounding rocks of the machine hall and emphasis is placed on the displacement law of the critical points on the downstream wall of the machine hall. According to the analysis results, the dissertation gives the deformation and plastic zone curves family of the rocks of four different superincumbent depths and makes fitting analysis on the curves to obtain corresponding displacement formulation in quadratic polynomial form.Secondly , Interface is used to simulate joints in the rock in this paper. The method isn't a traditionl means by which the normal and shear rigidity are considered in the computed model. The relation of geometrical parameters and rigidity of the joints are also considered in the based formulation. Then, the authors do lots of calculations, some analysis of the deformation are carried out. Thirdly, based on joints and static water existing around the main cavern, the author analyses the deformation effect of main cavern wall.At last ,based on above discussion ,some conclusions are given when the seepage field are considered .