This book explores the impact of notch geometry on the strength failure and crack evolution behavior of rock materials. It quantitatively compares simulated results from discrete element modeling with experimental findings related to the fracture mechanics of rock materials containing defects. Additionally, it establishes a relationship between the processes of crack evolution and the distribution of acoustic emissions in pre-fissured rock materials throughout the deformation process. The book discusses the mechanisms of crack evolution in pre-fissured rock materials under various confining pressures and analyzes how non-persistent joints affect the failure mechanisms of notched rock from a practical perspective.