[P02-07] Rainfall Infiltration and Slope Stability: a case study in Marumori, Miyagi, Japan
Keywords:Slope Stability, Rainfall Infiltration, GIS
Shallow landslides and slope failures in Marumori, Miyagi during the October 2019 typhoon Hagibigs are acknowledged to be induced by heavy rainfall. Using rainfall intensity and soil characteristics, infiltration capacity and depth of infiltration can be estimated. In this study, the Green-Ampt equation, adapted for inclined surfaces, is used to estimate infiltration depths along critical slopes. Assigning the computed infiltration depths as the slip surface depth, the factor of safety is then calculated using the infinite slope stability model. Translating this model into raster processes, a visualization map of a time-varying factor of safety for Marumori can be generated.