Failure experiment of soft-hard interlayer bedding rock slope

Abstract

Bedding rock slopes with soft-hard interlayers have complicated failure types and are difficult to prevent. In view of the prone and frequent occurrence of such slope geological disasters, research is carried out from the aspects of slope angle, rock formation tendency and combination form, and joint distribution.Slope physical model testing is an important means to reveal the mechanism of slope deformation and failure.Based on similarity theory, this paper takes the Sunjia landslide in Wanzhou District, Chongqing City, as the engineering support and designs the indoor slope physical model test according to the geological exploration report of the landslide area.The test simulates gravity loading through a jack-up model box and explores the relationship between the front slope angle and the weak interlayer inclination when the bedding rock slope slope is damaged.Combined with the finite element analysis software Plaxis 2D, multiple sets of numerical simulation tests were performed on the physical model to verify the failure mechanism of bedding rock slopes with soft-hard interlayers. The results show that for a bedding rock slope, when the inclination angle of the weak interlayer is approximately 22°, the leading edge excavation slope angle is about 58°, the bedding rock slope is prone to sliding, and the sliding surface is the joint surface of the trailing edge and the weak interlayer. Through the surface.Therefore, the stability of a bedding rock slope is controlled by the density of the layer and the joint surface. When the slope contains multiple weak layers, it is easy to break along the layer and the back edge of the joint. As the number of weak surfaces increases, the slope stability coefficient gradually decreases.The research results can provide a theoretical basis for the instability mechanism and stability evaluation of bedding rock slopes caused by road excavation and slope cutting, and provide support for the prediction of the bedding rock slope instability.

Keywords

• soft-hard interlayer
• bedding rock slope
• slope physical model test
• numerical simulation
• failure mechanism