Abstract:Therefore, taking the open-pit mining project of Gongchangling Iron Mine as the research object, based on quantitative GSI index and Hoek Brown (H-B) strength criterion, the H-B strength parameters were calculated and obtained, and then converted into equivalent Mohr Coulomb (M-C) strength parameters through mathematical fitting method, providing theoretical basis for engineering design and construction. And by introducing the theory of extension and combining various traditional grading methods, a comprehensive evaluation model for rock mass quality is established based on the D-S evidence theory and the fusion of various rock mass quality grading results. The research results indicate that the use of rock acoustic testing reveals the distribution characteristics of the integrity and weathering degree of the target borehole rock mass, providing key geomechanical basis for the stability assessment and mining design of mining engineering; A quantitative evaluation system combining Geological Strength Index (GSI) and Hoek Brown (H-B) strength criterion was established to accurately determine the H-B strength characteristic values of the target rock mass. Based on numerical fitting, the equivalent Mohr Coulomb (M-C) strength parameters were further derived, laying a reliable data foundation for numerical simulation of rock mass stability; Using RMR, Q, BQ, extension theory, and D-S evidence theory for comprehensive evaluation, multi-dimensional grading is carried out to ultimately determine the quality level of each target rock mass.