中文摘要：

为了分析强降雨条件下含软弱夹层土坡稳定性影响因素的敏感性，结合长沙一湘潭高速公路某路堑左侧边坡现场调研资料，基于饱和一非饱和渗流理论，建立了含软弱夹层土坡数值分析模型。选取夹层倾角、夹层厚度、夹层埋深以及夹层层数这4种内在影响因素，分析了各因素变化对边坡稳定性的影响规律。研究结果表明，长沙一湘潭高速公路某路段路堑左侧边坡软弱夹层倾角的临界目值范围为30°～35°；在降雨阶段，边坡安全系数随着降雨历时的增加而逐渐降低，雨停后安全系数又随着入渗雨水的消散而缓慢升高，但回升速率明显低于下降速率；在强降雨条件下，软弱夹层内在因素的变化是导致边坡稳定性降低的主要因素，其中连续降雨方案的影响程度较大；无论是否考虑降雨条件，软弱夹层内在因素变化对边坡稳定性影响的敏感性都为：夹层层数〉夹层倾角〉夹层厚度〉夹层埋深。

英文摘要：

In order to analyze the sensitivity of factors influencing the stability of soil slope with soft interlayer under heavy rainfall conditions, based on the field survey data of the left slope of cutting in a section of Changsha-Xiangtan expressway and Saturated-Unsaturated seepage theory, the numerical analysis model of the weak interlayer soil slope is established. And 4 internal factors, such as the dip angle of the interlayer, the interlayer thickness, the interlayer embedment depth and the interlayer number are selected to analyze the influence law of the various factors on the slope stability. The analysis results show that the critical value of the interlayer inclination of the left slope of cutting in a section of Changsha-Xiangtan expressway is 30°-35°. In the rainfall stage, the safety factor of slope decreases gradually with the increase of rainfall duration. After rain stops, the safety factor increases slowly with the dissipation of infiltration rainwater, but the recovery rate is obviously lower than the decline rate. Under the heavy rainfall condition, the change of the inner factor of soft interlayer is the main factor that leads to the decrease of slope stability, among which the influence of continuous rainfall scheme is larger. Whether or not the rainfall is considered, the sensitivity of the change of the internal factors to the slope stability is as follows： interlayer number〉interlayer inclination angle〉 interlayer thiekness〉 interlayer buried depth.