Method of Residual-State Creep Test to Understand the Creeping Behaviour of Landslide Soils

Abstract

Many researchers have studied creeping behaviour of landslide soils in the laboratory using both odometer and triaxial tests; however in most cases, they have only concentrated on the pre-peak creep behaviour of soil, which does not adequately explain the creep movement of landslides that undergo large displacements at close-to-residual state of shear. This necessitates the importance of further studying creep behaviour of clayey soils in residual-state of shear. In order to investigate creep behaviour of clayey soils, a method of residual-state creep test in a modified torsional ring shear machine is developed in laboratory, which can simulate the creeping behaviour of a large-scale landslide. This paper discusses on the typical results obtained from four representative landslide soils, i.e., commercially available Kaolin clay and three other samples from the landslide area in Japan and Nepal which have higher percentage of smectite, chlorite, and mica. Finally, possibilities towards displacement prediction are discussed.