Rock Stabilization Analysis Of Underground Hydropower House Based On Rheology Effects

With the development of the engineering technology, great and rapid progress in underground engineering has been achieved, which expands the survival space of human being. People can be able to make use of the resource.. The development of underground engineerings increase quickly both in number and scale, some century and large hydrolic and hydropower engineering has been in construction, which is marked by the design of large or huge cavern group, the excavation work of cavern group disturb initial state of rock mass, From comparation of stability, safety and the technique economies analysis, it is necessary to carry on the construction numerical simulation.This paper takes ANSYS as preprocess platform to generate the finite element mesh dividing, it use data preprocess programme that designed by the author is adopted to change ANSYS file format to FLAC^3D file format. FLAC^3D is taken as calculation platform to simulate excavation work of cavern group.Base on characteristic distribution of initial stress field, the three-dimensional nonlinear back analytical numerical analysis model is built up and the fault and major joint cranny is simulated. . Back analysis method is adopted to get different side pressure coefficients by the Genetic Algorithm optimizing neural network method. Direct computations based on FLAC^3D are performed to check the back analysis results by measured principal stresses of some specific points, the back analysis result of initial stress field is used to the following creep calculation of mechanical rock masse .Based on the construction procedure and measured data, the first excavation is simulated to get the creeping parameter by trial calculations. And the parameters is taken into the next excavation calculation. And the accuracy of rock creeping parameters is checked by monitoring values of embedded multiple-point extensometers and statistics analysis, the analysis show the rock ceeping parameters are reasonable.With the initial stress field and creeping parameters from back analysis, the stability of the rock mass is simulated by construction procedure. The change of displacement, plastic zones, stress field of creeping calculating is analyzed, and some useful conclusions are given as a reference for the engineering practice.