Research on Back Analysis of Parameters for Excavation of the Underground Cavern Group of a Large-Scale Hydro-Power Station by Using Orthogonal Optimization

Engineering rock mass is a highly complex grey system, it is impossible to get all the parameters of rock mass by theoretical methods or field measurement approach. Underground engineering feedback analysis method is a reliable way to improve the design, optimization and construction. Based on the field data of underground cavern of a large-scale hydro-power station, the three-dimensional finite element model is established, and orthogonal experimental design and multi-objective optimization method are used for the rapid back analysis. This method could be used for obtaining the rock parameters by inversion calculating in the underground cavern construction of a large-scale hydro-power station. Meanwhile, the inversion parameters could also be applied in the excavation simulation for the next phase and the rock deformation and stability is predicted afterwards. The design and construction sectors are supposed to get its feedback in time, which effectively guarantees the stability of the surrounding rocks.