BACK-ANALYSIS ON MICROMECHANICAL PARAMETERS OF SOIL MASS USING BP NEURAL NETWORK

The micromechanical parameters of numerical model are obtained by repeated tests. Researches on particle material based on DEM are done. This article builds a numerical model of soil using LMGC, an open source software. And the 25 groups of macromechanical and micromechanical parameters calculated by the numerical model build a BP neural network. The BP neural network can back-calculates the micromechanical parameters if the macromechanical parameters of real physical tests are inputted into the neutral network. The numerical model can get the stress-strain line, stress train and particle rotation graph if the micromechanical parameters are set. The results show that the numerical model can well simulate the soil destruction process. The stress-strain line of numerical model matches well with the result of physical test. And error of macromechanical parameters calculated by BP neural network is about 10%.Besides, the stress train and particle rotation graph reveal the mechanism of soil destruction process.