Kavin kumar C,Heeralal M,Rakesh J Pillai,



Rainfall induced landslide,water pressure,suction distribution,numerical assessments,slope failure,


Rainfall is an extrinsic factor for the collapse of sloping terrain in Western Ghats of Kerala. Careful analysis of rainfall induced landslide is very important as people in the area have serious threat from landslides. In-depth assessments of variation of pore water pressure change in slopes during avalanche rainfalls are required for the purpose of mitigation. Soil water characteristic curve was prepared by field and laboratory tests so that various properties of unsaturated soil could be estimated. As suction distribution and rainfall infiltration were influenced by the ratio of rainfall intensity to saturated hydraulic conductivity, numerical models were analysed for various ratio of rainfall intensities. Variations of pore water pressure across different sections of the slope and reduction of factor of safety with respect to time and rainfall intensities were analysed. The results of the analyses can be applied in practice for determining the probability of landslide hazards in areas vulnerable to heavy rainfall and consequently damage from landslides.


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