Analytical method for flexural toppling failure of anti-dip rock slopes under seismic loads considering deformation coordination
High and steep anti-dip rock slopes are widely distributed in southwest China and rock layers in these slopes are easy to fracture at great depths,resulting in large scale landslides.Earthquakes are important external factors,inducing the toppling failure of anti-dip rock slopes.To analyze the stability of anti-dip rock slopes under seismic loads,adjacent rock layers are taken as the basic mechanical analysis unit,and regarded as cantilever beams with free or coordinated deformation.The discrimination conditions for two deformation modes are proposed.On this basis,a mechanical model for the flexural toppling failure of anti-dip rock slopes under seismic loads was proposed,and mechanical equilibrium equations for rock layers in the free or coordinated deformation zones were established.The calculation method for dividing rock layer deformation modes and the overall stability judgment method of the slope were provided.Based on MATLAB,the programming of flexural toppling analysis of anti-dip rock slopes under seismic loads was achieved.By comparing the UDEC numerical results of slopes under different earthquake impact coefficients,it was found that the maximum difference in slope safety factor between theoretical calculation and numerical simulation does not exceed 16％,and the range of free deformation zone and coordinated deformation zone is basically consistent,which verifies the correctness of the method proposed in this article.Parameter analysis found that the inclination angle of rock layers has a significant impact on seismic action,Under the same seismic impact coefficient,the reduction amplitude of the slope safety coefficient increases with the increase of inclination angle of rock layers.while the slope angle and rock layer thickness have a relatively small impact on seismic action.The study is helpful to prevent and control the failure of such rock slopes in seismic high-risk areas.
万方数据
维普
