A New Intelligent Back-Analysis Method Based on Differential Evolution Algorithm

In light of the fact that it is very hard to determine mechanics parameters of rock mass using the traditional method in geotechnical engineering, a new method based on Differential Evolution algorithm (DE) combined with Fast Lagrangian Analysis of Continua in 3 Dimension (FLAC3D) numerical calculation code is proposed for identification of the mechanics parameters of rock mass. At first, stochastic mechanics parameters are initialized. Then, the difference in displacement between the numerical value and in-situ measurements is regarded as fitness value to evaluate quality of the trial mechanics parameters. Furthermore, mechanics parameters of rock mass are updated continually according to differential evolution rule until the optimum mechanic parameters are found. The results of case study and application in tunnel engineering both show that the method is feasible and efficient for identifying mechanics parameters of rock mass.