Analytical Solution of Rainfall Infiltration in Unsaturated Soil Slopes Considering Initial Water Content Distribution

This paper proposes the analytical solution of rainfall infiltration in unsaturated soil slopes considering the initial distribution of water content under various rainfall intensities. A computational model of the seepage field was established for the unsaturated soil slope, and the governing equation of seepage field of the unsaturated soil slope was derived from the established model. Subsequently, the analytical solution for the distribution of the real-time water content in the seepage field was obtained, considering various rainfall intensities. The analytical results are then compared with those by other methods (i.e., experimental test and numerical analysis). The comparative results show that the analytical solution is close to the that obtained by other methods. Besides, the time of water accumulation and the distribution function of water content at any moment can be accurately obtained using the analytical model. The analytical model proposed in this paper can indicate accurate results of the seepage field in unsaturated soil slopes, considering the initial water content distribution of soil.