A High Rock Slope's Stability Calculation and Back Analysis of Mechanical Parameters
|School||Central South University|
|Keywords||rock-slope ANSYS Orthogonal experimental design backanalysis of mechanical parameters BP neural network safety factor FLAC3D|
Mechanical parameters of rock mass of rock slope are of great significance in the study of slope problems such as the stability evaluation of rock slope. It’s always an important issue for research workers about how to obtain the exact mechanical parameters of rock.This paper mainly studies how to obtain the mechanical parameters of rock mass by using the displacement back analysis method and to get the information of the Stability analysis of rock slope. The main contents include:using FLAC3D software to simulate the excavation of the slope and the stability analysis.Then study for the analysis of the mechanical parameters of rock by BP neural network.Firstly, to set monitoring points at every step to monitor the excavation of surface displacement in the digging process of slope. Secondly, simulate the digging process of slope by using FLAC3D software. As the model is complex, we choose modeling by ANSYS and then import into FLAC3D for numerical analysis. Based on structural characteristics of the slope, numerical analysis is done on mohr Coulomb constitutive model and the input mechanical parameters is modified by Orthogonal experimental design and then the surface displacement of slope excavation which is calculated by different input parameters is obtained. Thirdly, on the basis of the input set of the slope deep displacement obtained by FLAC3D numerical analysis and the output sets of the back analysis of the corresponding mechanical parameters, the BP neural network is established and the network training and simulation is carried on. Finally, take the measured values of the slope surface displacement as input set for back analysis, do back analysis on mechanical parameters and compare back analysis value of mechanical parameters with theoretical values.To have a study of stability analysis of slope by theoretical Values and to analyze the excavation condition under supporting and without supporting effect to get slope safety factor and plastic through the regional information, which provides the basis for the necessity of slope excavation and support.The feasibility and reliability of using BP neural network to do back analysis of mechanical parameters of rock mass and using Numerical analysis to analyze slope stability both are verified, then a simple and efficient method for obtaining mechanics parameters of rock mass is provided.