Shear deformation in unsaturated slope models due to wetting with various densities, inclination, and overburden pressures

Abstract

This paper discusses an experimental study and existing site condition of rainfall induced landslide sensitive mountainous site. Soil behavior of the site was understood by using slope angle, soil gradation test. Disturbed and undisturbed soil samples were taken from the site for testing purpose. Shear deformation with the change of volumetric water content was checked by using 1.3(g/m³) and 1.4(g/m³) bulk density sample. The modified shear test apparatus was used to determine the shear failure at different slope angle such as 25, 30 and 35 degrees. Shear box sample size was 30cm x20cm x 7cm and overburden pressure on the sample was applied by using steel plates. Constant water flow was uniformly applied on top and bottom surface of the soil sample which is enclosed by the shear box. Numbers of three moisture sensors were used in shear plane to measure the volumetric water content (VWC) and displacement transducer was used to measure the shear displacement of the shear box. The results suggest that ground with high bulk density is more resist to shear failure. The results also shown that the required moisture content for the shear failure is decreasing when increasing the sample slope angle of the similar bulk density condition.