Seepage Response along with Fine Particle Migration of a Loose Soil Slope under Rainfall Infiltration

Fine particle migration is common in loose slopes with wide gradation characteristics under rainfall infiltration conditions. The seepage characteristics and stability of loose soil slopes are affected by the migration of fine particles along them. First, a flume model test was conducted to illustrate the migration law of fine particles under rainfall conditions. It was found that fine particles primarily migrated to two zones of the model slope (i.e., the shallow part of the slope and the toe of the slope) and most fine particles accumulated close to the slope toe. Second, the influence of fine particle migration on the seepage stability of loose soil slopes was also explored. The equation for the unsaturated permeability coefficient was then established considering the influence of fine particle migration. The present equation was further discussed by numerical simulations in contrast to the case where the fine particle migration was neglected. The results show that the fine particle migration along with rainfall infiltration has obvious influence on the seepage field, displacement field, and stability of the slope.