Undrained Stress-controlled Dynamic-loading Ring-shear Test to Simulate Initiation and Post-failure Motion of Landslides

Abstract

Landslides are gravitational mass movements of rock, debris or earth. Shear deformation in landslides before failure conforms to the field of statics. But shear deformation during seismic loading and post-failure motion of landslides conforms to the field of dynamics. Thus, study of the initiation of earthquake-induced landslides and rapid landslide motion needs to develop “Landslide dynamics” involving dynamic loading and dynamic generation/dissipation of excess pore-water pressure during motion. New developments in science can be facilitated by new technological advances. This study aimed to develop a new testing method that can geotechnically simulate the formation of the shear zone and the following long and rapid shear displacement that occurs in high-velocity landslides. Sassa K and his colleagues at DPRI (Disaster Prevention Research Institute), Kyoto University, have worked to develop an undrained stress-controlled dynamic-loading ring-shear apparatus and its testing method for this purpose. This paper describes the development of this testing method, and its application to the study of earthquake-induced landslides and landslide triggered debris flows in Japan.