A New Analysis Method for the Influencing Factors of Surrounding Rock Stability and its Application

Abstract

ABSTRACT: A new orthogonal matrix analysis method is proposed firstly in this paper, which aims at providing a new idea for the stability analysis of surrounding rock. Based on the orthogonal test method, a three-level analysis model is established. In detail, the geological conditions and rock masses grade, the variation of different factors, the deformation and fracture field of surrounding rock is regarded as the factor layer, the level layer, and the index layer, respectively. This method not only inherits the advantages of orthogonal test, but also avoids the influence of artificial weighting by establishing the index layer. Then, based on the combined finite-discrete element method, the influence of lateral pressure ratio, vertical stress, and rock mass grade on the surrounding rock stability is carried out by three analysis methods. The results show that the orthogonal matrix analysis method can well reflect the influence of factors, which is consistent with the result of the range analysis method and variance analysis method. In addition, this method can also realize the quantitative sensitivity analysis of factors under different levels, which is essential for the surrounding rock support design. 1. INTRODUCTION As we all know, the stability of roadways is affected by many factors. So, the research on the stability of surrounding rock is still a challenge. It has an important reference value for roadway excavation and support. Currently, many experts and scholars have proposed different methods and models to evaluate the stability of surrounding rocks. These include experimental methods (Chen et al., 2021), numerical simulation (Jia et al., 2022), theoretical analysis (Zhang et al., 2022), etc. The laboratory experiment is the basic method that evaluates the stability of surrounding rock based on the test result of rock samples. The numerical simulation is the most common method, which includes continuum mechanics methods (Tian et al., 2021; Wang et al., 2022), discontinuous mechanics methods (Lisjak and Grasselli, 2014; Zhao et al., 2022), continuum and discontinuous combination method (Deng et al., 2020; Mahabadi et al., 2012). The theoretical analysis method is based on the analysis of the stress field and deformation field, which contains the longitudinal deformation profile (Sugimoto et al., 2019), ground reaction curves (Fang et al., 2013), the pressure arch (Kong et al., 2018) and the stand-up time (Nguyen and Nguyen, 2015).