Effect of relict joint in rain induced slope failures in residual soil

Abstract

Rain induced slope failures i s a common geotechnical hazards in most parts of the world. Particularly in the tropicaI regions, which are covered with residual soil, the temporal frequency of rainfall induced slope failures is very high. These problems are encountered in the construction of highway with the very high cut slopes. So the special focus should consider in the highway construction. Residual soils are formed due to weathering of rocks. The residual soils are heterogeneous due to variable weathering of the jointed mass rock. Joints are formed due to decomposition of rock Due to the presence of relic joints, the behavior of the residual soil is quite complex. Generally the ground water table is low during the dry season and these soils are in an unsaturated state. The shear strength of a soil is enhanced by matric suction. As a result of infdtration of rain water, the matric suction will be destroyed and ground water table rise.. Due to the loss of matric suction the slope failures can induce. This aspect is studied in this research with the infiltration model by using SEEPW, SLOPE Wsoft ware.