Slopes with dominant seepage interlayers (DSI)often have relatively high uncertainty in their seepage field under the action of rainfall infiltration, which brings difficulties to the stability evaluation.In this regard, probabilistic methods are usually used to analyze the stability of such slopes.For analyzing the reliability of slopes with DSI under rainfall infiltration, the point estimation-finite element method used in the stress analysis was introduced to the slope seepage-stability analysis, and a method for seepage probability and reliability analysis of slopes was developed considering the uncertainty of permeability of DSI.Then, by taking a soil slope with gravel interlayer acting as DSI in Guangxi Province as the engineering case, the seepage probability of DSI under rainfall infiltration was analyzed, and then the slope reliability analysis was conducted based on the seepage probability.Results show that:① In the slope with DSI, the depth of rainwater infiltration along DSI is significantly higher than that along the slope surface; the uncertainty of the permeability of DSI has a great impact on the seepage field, which results in the strong uncertainty of slope stability; ② With the rainwater infiltration in the slope with DSI, the failure probability of different potential slip surfaces generally increases, and the position of the most dangerous slip surface evolves from the upper part to the lower part of the slope. The prediction of the position of slip surface is consistent with the practice; ③The proposed probability analysis method, with the advantages of small calculation amount, is suitable and can be used as a new method for analyzing the stability of slopes with DSI under the influence of rainfall infiltration.

极限平衡法是边坡稳定性分析与支护设计中最为常用的—种方法.为研究不同极限平衡法在多级边坡稳定性分析中的差异,本文以满足力矩平衡的Bishop法、满足力平衡的严格Janbu法和同时满足力矩和力平衡的Morgenstern-Price法等具有代表性的极限平衡法为例,讨论不同极限平衡法在条块受力假设、整体平衡方程等方面的异同;并以广西某多级公路边坡为依托工程,采用上述3种极限平衡法分别计算该边坡在正常工况和降雨工况下的安全系数,综合评价该边坡的稳定性,为相关边坡工程提供参考.

含碎石夹层的土坡降雨作用下的渗透特性对边坡的稳定性具有重要影响.针对降雨诱发含碎石夹层土坡破坏演化规律的研究不足,通过概化含碎石夹层土坡的几何模型并构造相关受力分析模型,分析了碎石夹层优势渗透面对边坡稳定性的影响机制;基于Janbu法推导了考虑优势渗透面效应的极限平衡法公式,并基于Geostudio平台将其应用于数值计算;通过对工程实例的分析,研究了含碎石夹层土坡降雨作用下优势渗透面的形成过程及边坡破坏演化规律.结果表明:碎石夹层因其强渗透特性和受雨水汇集的影响,在降雨作用下容易沿碎石夹层向下形成优势渗透面,且优势渗透面效应随着降雨持时的增加而愈发显著;优势渗透面为雨水的快速下渗提供了通道,造成碎石夹层的抗剪强度急剧降低,边坡潜在滑动面的安全系数不断降低,最危险滑动面的空间位置由边坡上部不断向下演化直至发生滑坡.