Nonlinear Regression Analysis for Deep Rock Mass Parameters of the Hoek-Brown Failure Criterion Based on the Differential Evolution

摘要

The Hoek-Brown (H-B) failure criterion is an empirical failure criterion. The estimates of Hoek-Brown criterion parameters, such as the geological strength index (GSI) and the disturbance coefficient (D), are usually subjective. This paper focused on modifying the initial estimates of GSI and D to improve the accuracy of parameters. The nonlinear regression model (NLRM) of the Hoek-Brown failure criterion was proposed to analyze the rock parameters by using the sensitivity analysis and the displacement equation of the surrounding rocks. Then, a reasonable back analysis method was developed by introducing the differential evolution (DE), which was used to accurately obtain the parameters of the Hoek-Brown failure criterion in practical engineering. This method was successfully used to analyze the stability of the roadway in a deep coal mine. The results showed that the NLRM can better reflect the relationship between GSI, D, mu and the displacement of roadways, and the back analysis results are consistent with the filed monitoring results. This method can provide a helpful reference for modifying the influence of empirical and subjective factors on H-B parameters selection, and improving the accuracy of Hoek-Brown criterion parameters in the similar engineering applications.