Research on multistage deformation law of bedding rock slopes based on NPR anchor cable monitoring

The bedding rock slope with sand-mudstone interbeds is mostly developed in the coal-bearing strata of Shanxi Province. Affected by rainfall and groundwater，landslide disasters are frequent. Based on the limit equilibrium method and considering the slope parameters such as the height h of the free surface at the foot of the slope，the slope angle α，the strata inclination β ，the weight γ of the sliding mass，the length L of the slip surface，and the mechanical parameters(c， )of the soft rock strength of the slip zone，a mechanical analysis model is established to study the multi-stage deformation law of bedding rock slopes with weak interlayers under the support of NPR anchor cables. Through formula derivation，two types of NPR anchor cable-supported slopes under different strength parameters in the softening and creep process of the rock and soil in the slip zone are determined：the overall stable type and the local stable type，and the multi-stage deformation laws of the two types of slopes during strong rainfall are analyzed from the mechanism. The formula is derived to qualitatively analyze the change of the length of the sliding surface when the slope is unstable under the same condition of whether the NPR anchor cable is set，and the influence on the change of the landslide scale is obtained，for the same condition slope with NPR anchor cable whether considering the hydraulic action or not，the change of slip surface length is qualitatively analyzed when the slope is unstable，and the influence on the change of landslide scale is obtained. Finally，the application of the remote monitoring and early warning system of Newtonian force of landslide geological disaster developed by He Manchao′s team in the Lujumao landslide in Liulin County，Shanxi Province is used. The actual early warning results reflected by the monitoring data are consistent with the theoretical derivation of the slope instability model. © 2024 Academia Sinica. All rights reserved.