Investigation into the Kinematic Characteristics of Dry Granular Flow and Its Interaction Mechanism with Vertical Barriers

Granular flow, a dynamic mass from loose deposits or landslides in mountains, severely damages structures along its path. Barriers are widely used to mitigate such disasters, making studies on granular flow kinematics and interaction with barriers crucial for disaster reduction. This study conducts physical model experiments to observe the movement and impact behavior of dry granular flow, exploring the effects of variations in particle size, channel slope angle, and barrier height on the interaction between granular flow and vertical barriers. Additionally, a model for estimating the impact force of dry granular flow on vertical barriers is proposed, with its reliability validated through experimental data. The results indicate that barriers exhibit a significant retention effect on granular flow. Larger particle sizes and steeper slope angles lead to a marked increase in both the mobility of granular flow and its impact force on barriers. A substantial increase in barrier height significantly enhances its ability to block or intercept the flow. The results in the research clarify how particle size, slope angle, and barrier height jointly govern deposit morphology and peak impact force on vertical walls, and the proposed force decomposition provides a physically interpretable framework for estimating wall-normal impact forces from measurable kinematic quantities.