Integrative Analysis of Surface Runoff and Macropore Flow for Slopes under Rainfall Conditions

Abstract

Estimating runoff and infiltration in slopes is essential to predict flooding and landslide triggering. An approach jointly using a dual-permeability model and a kinematic wave model was proposed for integrative analyses of infiltration and surface runoff of rainwater for slopes with macropores in soils subjected to rainfalls. Laboratory tests were conducted to evaluate the performance of the proposed approach. Analyses showed that the presence of macropores greatly facilitates rainwater movement in the slope and the maximum depth of wetting front could be one order of magnitude larger than in cases without macropores. The influence of rainfall intensity, initial pore water pressure, coefficient of permeability of soil matrix, and slope angle was also examined.