西南地区某高速公路边坡危岩体稳定可靠性评价

Reliability Evaluation for Slopes in Highway of Southwest China

依托高速公路岩质边坡的危岩体开展稳定可靠性研究,对研究区调查报告进行分析,研究了危岩体的稳定安全系数与失稳概率。危岩边坡研究区长约1.1 km,存在30处危岩体,失稳破坏多以滑移式为主,重点研究了14处滑移式危岩。并根据危岩所处位置,将危岩分为A、B、C三个分区,分析了危岩失稳的原因、诱发因素以及失稳破坏的方式。分别基于刚体极限平衡法和一次二阶矩阵方法(FOSM法),研究了危岩体在正常、暴雨、地震三个工况下的稳定安全系数与失稳概率。研究结果表明,在正常工况下,大部分危岩体失稳概率小于50%,处于欠稳定状态,失稳可能性较小;在暴雨和地震工况下,少数危岩体失稳概率大于50%,处于较不稳定状态,失稳可能性较大。

Reliability and stability studies were carried out on the dangerous rock mass of the rock slope of an expressway.The investigation report of the study area was analyzed,and the stability safety factor and instability probability of the dangerous rock mass were studied.The dangerous rock slope research area is about 1.1 km long,and there are 30 dangerous rock bodies.Most of the instability rocks belong to the slip type.14 slip type dangerous rocks are mainly studied.According to the location of the dangerous rock,the dangerous rock is divided into three sub-areas A,B,and C.And the causes,inducing factors of instability and destruction of the dangerous rock mass are analyzed.Based on the rigid body limit equilibrium method and the first-order second-order matrix method(FOSM method),the stability safety factor and the probability of instability of the dangerous rock mass under three working conditions of normal,heavy rain and earthquake were studied.The research results show that under normal operating conditions,the probability of instability of most dangerous rock masses is less than 50%,which is in an unstable state,and the probability of instability is small;under heavy rain and earthquake conditions,the probability of instability of a few dangerous rock masses is greater than 50%,in a relatively unstable state,with a high probability of instability.