Abstract:

A series of physical simulation experiments of slope rainfall erosion were conducted in laboratory on steep loess slope of 70° in Western Liaoning under a rainfall intensity of 2.7 mm/min.  It was found that as the rainfall lasted, the energy and erosion intensity of water flow increased. The erosion pattern verified from splash and sheet erosion to rill erosion, and finally evolved into gully erosion and collapse on top of the slope. Based on the experiment, the distribution of rainfall seepage in the slope was simulated by SEEP/W. Results showed that the water pressure on top of the slope was the highest, and it reduced as the height decreased. The microcosmic motion of soil particle was also simulated by PFC2D, it was found that particles on top of the slope were firstly washed off by water flow, and rapidly fell down. The simulation results are consistent with the indoor model experiment, which provide a reference for research on rainfall erosion properties of loess slope.

Key words: loess in western Liaoning, steep slope, physical simulation, rainfall erosion, seepage law, particle flow code