Abstract:In order to study the influence of gravel shape on the stability and deformation damage characteristics of gravel-bearing granite residual soil slopes under rainfall conditions, the macroscopic vertical displacement and deformation damage of slopes as well as the change of wetting front were comparatively analyzed by carrying out rainfall slope modeling test and combining with the numerical simulation of CFD-DEM to analyze the developmental pattern of displacement field and sliding surface, the fine-scale contact force chain, coordination number, and group structure anisotropy. The results show that: the safety coefficient of slopes containing rounded gravel is the smallest and that of slopes containing angular gravel is the largest. With the increase of precipitation time from 0 to 3 hours, the safety coefficients of slopes containing rounded gravel, pebble gravel and angular gravel decrease by 40%, 33% and 32%, respectively, and the degree of influence by rainfall is in descending order of rounded gravel, pebble gravel and angular gravel slopes. With the increase of the aspect ratio and prism angle, the embedded occlusion effect of gravel is gradually enhanced, and the three damage modes of circular arc damage, toothed arc damage, and offset damage appear in the corresponding slopes in descending order; after the slope’s destabilization and failure, the strong contact force chains of the rounded gravel-containing, pebble gravel-containing, and angular gravel-containing slopes are characterized by intertwined, weak continuity, and unevenness distribution; with the increase of the aspect ratio and prism angle of the gravels, the extent of the contact anisotropy of rounded gravel-containing, pebble gravel-containing and angular gravel-containing slopes is gradually increased.