Experiments study on landslide motion and damming deposit for particle and block materials with different mechanical properties

This study explores the impact of granular materials with varying moisture contents and particle sizes, as well as block materials with different volumes and layer strengths, on landslide fragmentation, motion, and deposit. The experimental results show that as particle size increases, the maximum dam height (H_max) and width (W_max) increase, while the minimum dam height (H_min) decreases, indicating an improvement in the stability of landslide dams. Larger particle sizes are less sensitive to changes in moisture content. Additionally, moisture content inhibits W_max, with mixed particle-size materials showing a greater reduction compared to single particle-size materials. As W_max increases, the maximum dam length (L_max) decreases exponentially. Sliding time (T_s), deposition time (T_d), and total time (T) decrease as particle size increases. For mixed particle-size materials, a more continuous particle size distribution further reduces T_s, T_d, and T. Block material experiments show that with increasing block volume, W_max, L_max, and H_max increase significantly, with corresponding increases in T_s, T_d, and T. When the strength of the lower layer material decreases, W_max and H_max decrease, while T_s, T_d, and T increase. Conversely, when the lower layer material strength increases, the opposite effect is observed. Frictional energy loss (E_f) is the primary energy loss pathway, with both total energy loss and E_f decreasing with increasing particle size. Localized energy losses are mainly due to terrain collisions, independent of moisture content.