GIS-based prediction method of landslide susceptibility using a rainfall infiltration-groundwater flow model

This paper describes a physical-based model to predict rainfall-induced landsides. Special attention was given to the introduction of a GIS-based model, YS-Slope model (YonSei-Slope model), which can evaluate the susceptibility of landslides. The model has been improved by incorporating the combined effects of groundwater flow and rainfall infiltration into the raster model. The two dimensional Darcy's law was used to reflect the effect of groundwater flow in the soil slope, and the modified Green–Ampt model, which is a one-dimensional infiltration model, was selected to capture the effect of rainfall infiltration into the soil mass. These elements were integrated into the infinite slope-stability model for a rainfall-induced landslide. The proposed model was verified by comparing the results from existing models as well as an actual slope failure case that occurred in Korea. With further study, the YS-model could be adopted as a prediction method for rainfall-induced landslides. •A physically-based predictive model of rainfall-induced landslides has been developed.•The model considers the rainfall infiltration, recharge and groundwater flow over time.•The model considers the shallow landslide controlled by groundwater flow and wetting band.•A series of analytical studies were compared with case histories, and agreed well.•The model can be used for predicting the two types of rainfall-induced landslides.