Physical model test of the deformation behavior and evolutionary process of the multi-sliding zone landslide

Many large landslides may have multi-sliding zones that are simultaneously active due to the influence of engineering geological and hydrogeological conditions. Here, a simplified multi-sliding zone landslide model is developed to reproduce the deformation behavior and evolution process of landslides. A multi-sensor monitoring system is implemented to record the surface deformation, subsurface deformation, and soil pressure during the test. The flexible inclinometer sensor technique is utilized for subsurface relative deformation monitoring in the model test. A uniform thrust loading is applied on the trailing edge of the model. The results show that the displacement evolution reflects four stages, namely, initial, constant, accelerative, and failure stages, and the evolutionary process of each landslide at different depths is different. The variation trends of soil pressure are similar to those of subsurface displacement, which can be classified into four analogous stages. When landslide failure occurs, the soil pressure drops suddenly. The variation of soil pressure could reflect the energy state of the multi-sliding zone landslide. The correlation coefficients between the soil pressure and the subsurface relative displacement are different among the multi-sliding zones. During the test, the soil pressure of the multi-sliding zones landslide presents a complicated multistage trapezoidal distribution, and the multi-sliding zones have the greater soil pressures. Under the action of thrust loading and gravity, translational sliding with multi-sliding zones occurred, and local shear sliding occurs at the front of the landslide. This research provides improved insight into the evolutionary process of the multi-sliding zone landslide.