Shear Band Propagation and Mechanical Behaviours of Landslides of Slope Under Top Loading

Slope stability is conventionally regarded as mainly relating to the configuration of slip surface in the limited equilibrium method and the bearing capacity theories. However, few studies are reported to study a different way of propagation of a slip surface with the same configuration might affect the mechanical behaviour of the slope and the slope stability. In this paper, the role of shear band propagation in the slope failure process is studied by both laboratory model tests using transparent soil technique and numerical model of Discrete Element Analysis. The pre-failure behaviour of slopes is studied in two model tests that have a similar configuration of slip surface but undergoes different processes of shear band evolution. Results show that the slope pre-failure behaviour could be much different in a landslide that has the same soil properties and the same morphology of slip surface. The evolution of shear bands has a primary influence on the pre-failure behaviour of the slope. The coalescence of shear bands discretizes the slope body into several blocks thus causing the temporal and spatial variation of the slope movement, stress, void ratio and energy dissipation. Therefore, besides the configuration of slip surface, the process of shear band evolution is suggested to be considered when analysing landslide failure mechanism, slope stability and bearing capacity assessment