Stability Analysis And Slope Rate Optimization Of High And Steep Slope

The high and steep slope has the characteristics of high slope,steep slope angle and serious instability hazard.The change of excavation slope also has a great influence on the stability of the slope,which is easy to lead to the occurrence of landslide,collapse and other safety hazards.According to the on-site geological data,numerical simulation is used to study the stability state of the slope after excavation at different slope rates,and the stability under different slopes is verified by similar simulation tests,and the main research work and results are as follows:(1)According to the original hydrogeological data,the rock mass structure and hydrogeological conditions in the slope area were determined,the mechanical parameters of the rock mass were determined through physical and mechanical tests,and the engineering rock mass classification was carried out.(2)The unloading effect of rock mass is analyzed from the angle of the variation characteristics of stress field and the influence range of unloading spring back under the condition of multi-step slope excavation.At the same time,the minimum safety factor of slope is calculated and optimized by the limit equilibrium method.(3)According to the numerical calculation,the safety factor of the original design line scheme is 1.094 when excavated to the final limit,and the slope safety factor of the optimized design scheme can reach 1.283 and 1.152,which is 15% ～ 20% higher,and the slope is in a stable state.Combined with the excavation volume and rock layer distribution,the excavation scheme of first slow and then steep 45°-55° is selected as the optimal excavation scheme,which meet the excavation requirements.(4)The slope similarity simulation test was carried out to verify the optimal slope excavation angle.The experimental results showed that the maximum vertical displacement appeared at the top of the slope and the maximum horizontal displacement appeared at the free surface in the middle of the slope,which was consistent with the numerical simulation deformation characteristics.The optimization scheme was reasonable.This paper has 76 figures,15 tables and 66 references.