福建漳州某高速公路滑坡数值分析及加固治理研究

Numerical analysis and reinforcement management of a highway landslide in Fujian Zhangzhou

摘要:

为治理某滑坡，基于现场勘察资料构建了边坡数值分析模型，以边坡特征点位移出现拐点为判据，采用强度折减法确定边坡天然工况稳定性系数为1.05，该边坡稳定性水平不满足工程规范要求，处于欠稳定状态。结合数值分析结果、专家现场分析意见及边坡加固措施的作用机理，确定了3种加固治理方案，方案1为“圆形抗滑桩+锚杆+截排水”，方案2为“方形抗滑桩+圆形抗滑桩+锚杆+截排水”，方案3为“方形抗滑桩+圆形抗滑桩+截排水”。基于有限元数值模型分析边坡岩土体、抗滑桩和锚杆的应力场、位移场及坡体稳定性系数变化，计算得到3种加固方案对应的边坡天然工况稳定性系数分别为1.39、1.28、1.18，分别较加固前提升了32.4%、21.9%、12.4%。经综合对比3种加固方案的加固措施和坡体应力、位移变化及其加固效果和经济性水平，综合确定方案1为最终加固方案。

Abstract:

In order to manage a landslide， a numerical analysis model of the slope was constructed based on the on-site investigation data， taking the inflection point of the displacement of the characteristic point of the slope as the criterion， and adopting the strength discount method to determine the stability coefficient of the natural working condition of the slope to be 1.05， it was determined that the stability level of the slope did not meet the requirements of the engineering specification， and it was in the state of understability. Combined with the numerical analysis results， experts’ on-site analysis opinions and the mechanism of slope reinforcement measures， three kinds of reinforcement and management programs are determined， Program 1 is “Circular anti-slip piles + anchors + intercepting and draining”， Program 2 is “Square anti-slip piles + Circular anti-slip piles + Anchors + intercepting and draining”， and Program 3 is “Square anti-slip piles + Circular anti-slip piles + Intercepting and draining”. Based on the finite element numerical model to analyze the stress field， displacement field and slope stability coefficient changes of the rock and soil body， anti-slip piles and anchors， the stability coefficients of natural working conditions of the slope corresponding to the three reinforcement schemes were calculated to be 1.39， 1.28， and 1.18， which were 32.4% higher than those before reinforcement， and the stability coefficients of the natural working conditions were calculated to be 1.39， 1.28， and 1.18， which were 32.4% higher than those before reinforcement. Before the reinforcement， the stability coefficients of the natural working condition of the slope were 1.39， 1.28 and 1.18， respectively， which were 32.4%， 21.9% and 12.4% higher than those before the reinforcement； after comprehensively comparing the reinforcement measures of the three kinds of reinforcement schemes and the changes in the stress and displacement of the slope， as well as their reinforcement effects and economic levels， Scheme 1 was comprehensively determined as the final reinforcement scheme.