Insight into the overload failure mechanism of anchored slope with weak structural planes

Anchored slope with weak structural planes is a complex combination of rock mass and retaining structure, whose stability analysis is a necessary condition for road safety protection. To better understand the failure mechanism of anchored slope with weak structural planes under local overload, a series of physical model tests as well as corresponding numerical simulations have been conducted. Based on the test and numerical modeling results, the following conclusions are drawn: There is a serious stress concentration in the middle of the slope, which results in the failure of the slope surface in the shape of a bulge. Under the action of vertical stress, the anchored slope forms a wedge sliding zone along the weak structural plane. The overloading failure mode of the anchored slope with weak structural planes is collapse-upper extrusion-middle traction-lower, and the whole along the weak structural plane to the lower part of the wedge sliding failure. Overload changes the load bearing and deformation characteristics of anchored slope with weak structural planes. Additionally, the greatest stress occurs in the weak structural plane shear failure location, while the weak structural plane isolates the deformation and stress transfer. The axial force is distributed in the shape of “Z”, and the strength of the anchor cable in the middle and upper row should be appropriately strengthened.