锚杆抗滑桩安全预警及监测方案研究

Safety Early Warning and Monitoring Suggestions for Anti-slide Anchor Pile

锚杆抗滑桩是滑(边)坡加固的重要措施之一,由于岩土体介质的特殊性,其桩身及锚杆的实际应力应变与理论计算存在较大差异,致使其破坏机理与监测预警一直是工程界关注的重点和难点。通过开展锚杆抗滑桩的物理模型试验,深入研究锚杆抗滑桩变形破坏的演化规律,采用数据分析、数学模型拟合等方法,得出了锚杆抗滑桩的安全预警判据,并对锚杆抗滑桩施工期和运营期的安全监测方案提出建议。研究表明:锚杆抗滑桩从开始变形直至最终破坏大致都要经历弹性变形、弹塑性变形、塑性变形3个阶段;锚杆抗滑桩治理滑坡时,应重点对抗滑桩的桩顶位移、桩身应力应变及锚杆锚固力进行监测;建立锚杆应力值与桩顶位移的关系,预测锚杆是否屈服,为锚杆抗滑桩的监测预警提供了具有借鉴意义的思路。

Anti-slide anchor pile is an important reinforcement measure for sliding （side） slope. The failure mecha- nism and monitoring warning have been the focus and difficulty of engineering because of big difference between the measured and theoretical values of pile and anchor＇ s stress and strain. By physical model tests on anchor piles, the evolution of anchor pile＇ s deformation and failure were analyzed. Data analysis, mathematical model fitting and other methods were adopted to obtain the safety early warning criterion for anti-slide anchor pile. Suggestions for safety monitoring during anchor pile＇ s construction and operation were proposed. Results show that anchor piles generally go through three stages, namely elastic deformation, elasto-plastic deformation, and plastic deformation from the beginning until the final destruction. Monitoring on the pile top displacement, pile＇ s strain and stress, and anchor force should be emphasized. The relationship between anchor bolt stress value and pile top displacement should be obtained to predict the yielding of anchor bolt.