Impact of Bedding Angle on the Processes of Granular Column Collapse

ABSTRACT Gravity‐driven granular flows are a fundamental geological hazard. Among the various dynamic aspects of granular flow that are still being explored, the consideration of the bedding angle stands out as particularly significant. In this study, granular columns with different bedding angle and varying aspect ratios ( AR s) (initial height/initial length) were examined by discrete element method simulations. The results showed that the entire collapse process can be categorized into three distinct stages: initiation, collapse, and accumulation. The runout distance of the granular column with a larger bedding angle extends farther at the same time point. Two distinct final deposit profiles were identified with reduced trapezoidal and triangular shapes. A comparison of the absolute values of the maximum differential sedimentation angles shows a clear increase with the bedding angle. The highest value of maximum kinetic energy consistently occurs in the model with a bedding angle of 90° across all aspect ratios. The maximum dissipated energy increases as AR increases. The bedding angle significantly influences the extent of coordination number (CN) reduction, with larger bedding angles resulting in a more pronounced decrease in CN. As the bedding angle increases, the degree of anisotropy in the particle system intensifies. As the granular column collapses, the degree of anisotropy gradually diminishes. Increasing the aspect ratio significantly amplifies the degree of anisotropy.