A Study on Moisture Infiltration of Subsoil in a Slope due to Tropical Rainfall
Hiroyasu OHTSU, Yohei HOTTA, Suttisak SORALUMP and Tomonari NIIMURA
Abstract:Recently, in Japan, heavy rainfall observed during very short period, so-called Guerilla rainfall, which may be considered as one phenomenon of climate change, has highlighted as one of serious natural hazards that may cause slope failure. It should be considered that in the case of heavy rainfall, slope stability against rainfall heavily depends on amount of rainfall, which infiltrates into subsoil. Therefore, it is very important to develop a method that can clarify amount of rainfall infiltration into subsoil from total amount of rainfall, which is one of dominant factor on slope stability, and investigate mechanism of rainfall infiltration into subsoil. From such a viewpoint, this study discussed field data of surface flow, variation of soil moisture content and variation of pore water pressure monitored at investigated slope, Nakhon Nayok, Thailand. Key Words:Rainfall, Landslide, Infiltration, Field monitoring, Unsaturated soil