桩锚加固边坡的作用机理和稳定性分析研究

由某高速公路现场钻孔资料和地质调查分析得知,路基开挖后该边坡处于临滑状态。应用极限平衡原理,通过反演分析,求得滑动面的粘聚力c和内摩擦角φ。由锚索提供的水平抗力对自由段求极值确定锚索最优安装角。运用有限元法对纯桩和桩锚复合加固方案进行对比,计算出边坡上部经加固后向下传递的荷载。结果表明,桩锚方案加固效果显著。边坡锚索的预应力损失监测分析表明,锚索在锁定后470 d内的预应力损失为7.8%~12.9%,满足工程安全要求。工后2 a的运营阶段边坡处于稳定状态。

The analysis of mechanism and stability of slope reinforced with the pre-forced cable and anti-slipping Pile

As is known from the monitoring in-situ and geology, on an expressway the newly-cut slope is in the limit equilibrium status. According to limit equilibrium principle of slope, a back analysis has been made to get the cohesive factor c and internal friction angle tp of pre-existing potential instable discontinuities. And the fixing angle of cable is determined by the extremum of the aclinic anti-slipping force to free section. The FEM is adopted to compare the scheme of anti-slipping pile with the pre-forced cable and anti-slipping pile, and calculate the load transfered from the above reinforced slope. The result indicates that the reinforcing effect is distinct in the scheme of pre-forced cable and anti-slipping pile. Moreover,by monitoring and analyzing the loss of pre-force in the cables we find the range of it is 7.8% - 12.9% in 470 days after itg been fixed,which meets the demand of project safety. In the following 2 years in function, the slope can maintain stability .