Based on a large-scale slope toppling event in Guang'an Village, Wuxi County, Chongqing, this study establishes a three-dimensional concave geomechanical model that incorporates the anti-dip structure and weak foundation characteristics of the slope. Long-term geological effects were simulated through gravitational loading, with a multidimensional monitoring system capturing real-time deformation data. Analysis macroscopic deformation, three-dimensional displacement vectors, and slope pressure variations was conducted using multiple methods. An evaluation index for deformation stability is proposed, offering new insights into their failure mechanisms. Results show that when the dip angles of the slope and rock layers are small, shallow sliding failures occur due to tensile-shear failure along bedding planes. As the dip angles increase, the compression and sliding of the shale weak foundation intensify, leading to toppling and fracturing of the upper limestone, with significant surface uplift. The failure mode then transitions into a collapse dominated by overall failure. Interlayer tensile fractures in the shale are caused by bending creep and compressive deformation, while limestone fractures occur primarily in a brittle manner. The interaction between steep and gentle slopes, as well as the slope and dip angles, directly affects the deformation mode of anti-dip rock layers. The toppling angle and displacement distance of the rock layers are key indicators for assessing the deformation stability of anti-dip slopes. The deformation process, crack evolution, stability status, and timing of deformation control are analyzed in distinct stages. This study provides essential multidimensional data for slope stability evaluation, risk prediction, and engineering design in practical applications.
 

Anti-dip slope,Weak foundation,Toppling deformation,Stability evaluation,Multidimensional monitoring,Physical model experiment