This study uses a three-dimensional crack model to theoretically derive the HoekeBrown rock failure criterion based on the linear elastic fracture theory. Specifically, we argue that a failure characteristic factor ne...This study uses a three-dimensional crack model to theoretically derive the HoekeBrown rock failure criterion based on the linear elastic fracture theory. Specifically, we argue that a failure characteristic factor needs to exceed a critical value when macro-failure occurs. This factor is a product of the micro-failure orientation angle （characterizing the density and orientation of damaged micro-cracks） and the changing rate of the angle with respect to the major principal stress （characterizing the microscopic stability of damaged cracks）. We further demonstrate that the factor mathematically leads to the empirical HoekeBrown rock failure criterion. Thus, the proposed factor is able to successfully relate the evolution of microscopic damaged crack characteristics to macro-failure. Based on this theoretical development, we also propose a quantitative relationship between the brittleeductile transition point and confining pressure, which is consistent with experimental observations.展开更多
基金supported by the National Natural Science Foundation of China (No. 51374215)Fok Ying Tung Education Foundation (No. 142018)+1 种基金Beijing Major Scientific and Technological Achievements into Ground Cultivation Projectthe 111 Project (No. B14006)
文摘This study uses a three-dimensional crack model to theoretically derive the HoekeBrown rock failure criterion based on the linear elastic fracture theory. Specifically, we argue that a failure characteristic factor needs to exceed a critical value when macro-failure occurs. This factor is a product of the micro-failure orientation angle （characterizing the density and orientation of damaged micro-cracks） and the changing rate of the angle with respect to the major principal stress （characterizing the microscopic stability of damaged cracks）. We further demonstrate that the factor mathematically leads to the empirical HoekeBrown rock failure criterion. Thus, the proposed factor is able to successfully relate the evolution of microscopic damaged crack characteristics to macro-failure. Based on this theoretical development, we also propose a quantitative relationship between the brittleeductile transition point and confining pressure, which is consistent with experimental observations.
