考虑锚杆拉杆拉断、拉杆从注浆体中拔出、锚固段注浆体从岩体中拔出、外锚头破坏以及垫墩底岩体的压坏等失效模式,利用系统可靠性原理和极限平衡分析方法,建立了双滑块边坡多锚杆锚固系统可靠性分析模型。基于蒙特卡罗随机抽样原理提出了该类边坡锚固系统破坏概率的直接求解方法。最后结合算例,分别基于中值安全系数和破坏概率指标分析了各计算参数对计算结果的影响,并讨论了锚杆锚固角和被动滑块可能滑裂面倾角对锚固系统稳定性的影响。
The system reliability assessment model for the anchorange system of rock slope with many rock bolts was established,based on system reliability theory and limit equilibrium method,considering many possible failure modes of the anchor itself,such as the tensile failure of the free section,the shear failure between pull rod and grouting mass,grouting mass pulled out from surrounding rock and the failure of the rock below the mat piers,etc.A direct calculated method was presented to perform the probability of failure of the anchorange system for this kind of slopes,by making use of the random sampling idea of Monte Carlo technique.Lastly,with the examples for calculations,the paper analyzed the effects of the calculation parameters on the results,and discussed the effects of the anchorage angle of anchor and the inclination of passive slider on the stability of the anchorange system,based on the median factor of safety and the failure probability index.