Abstract: The interbedding slope with soft and hard strong-weathered rock is a special high slope, and the composition and properties of its structural surfaces are complex. The complexity and mutual influence of the interaction between the slope and supporting structure are relatively high, and it is the most probable that the collapsible structure will be destroyed when exposed to air. Based on the engineering of a deep cutting slope of Lanyong highway, we conducted in-situ monitoring the anchor rod stress, inner anchor force, and the displacement of the slope during and after the support. Moreover, numerical analysis was performed on the joint rock module of geotechnical engineering using PLAXIS software. The monitoring and numerical results indicate that the potential polygonal sliding surface of rock slope is formed by joint fractures and rock layers, and there is more than one potential sliding surface with the same sliding possibility. The retaining structure has great influence on the stability of structure surface when it penetrates any part of the fold line of the slip surface, but the penetrating shale surface has a greater effect on the structural surface than penetrating fissures. The variation of prestressing force of supporting anchor cable has a certain regularity, and the process of prestressing variation has a certain effect on the displacement of the slope and internal force of retaining supporting structure. For internal forces of supporting structure, the influence of the active deformation of the slope is greater than the influence of passive deformation of the slope. However, for a sensitive degree, sliding effect of the structural surface on the displacement of slope surface is less than the influence of internal forces of supporting structure. The support of the slope is stable, and the supporting design is reasonable, which can provide corresponding advice for the design of similar supporting slopes.

Key words: interbedding rock slope, potential sliding surface, slope-mass slide displacement, monitoring, anchor bar stress, anchoring force of cable bolts