Study of Anisotropic Behavior and Failure Characteristics of Layered Rock Based on Finite‐Discrete Element Method

ABSTRACT The bedding planes in layered rock masses are critical structures that control strength and stability. This study systematically investigates the strength and deformation characteristics of layered rock under different confined pressures using the FDEM method. Based on the global embedded cohesive element in Abaqus, the differentiated characterization of bedding planes and rock matrix was achieved, and numerical specimens of layered rock samples were constructed. To comprehensively reveal the mesoscopic failure mechanisms of layered rock under different confined pressures, the precise discrimination of crack dynamic thresholds based on material properties was achieved through Python. Simultaneously, the damage distribution of layered rock is obtained, which shows the spatial distribution of shear and tension damage intuitively. The results show that the compressive strength exhibits U‐shaped with the bedding inclination. The compressive strength, elastic modulus, and peak strain demonstrate an approximately linear relationship with the increase in confined pressure. The new discriminant threshold obtained by the study can effectively distinguish the damage modes, and under different confined pressures, the proportion of crack types and the proportion of cracks at the matrix and bedding plane are significantly dependent on the bedding inclination. Meanwhile, the failure mechanism of the samples can be effectively characterized by the spatial distribution characteristics of shear and tension damage. Finally, the applicability of the proposed method is verified by comparing the results with published literature.