【摘要】 含软弱夹层凝灰岩边坡受降雨影响诱发的滑坡一直是浙江省内公路边坡防治的主要对象。为进一步理解不同软弱夹层强度弱化模式对滑坡稳定性的影响，选取典型凝灰岩滑坡——浙江省松阳县呈田滑坡，采用Midas GTS NX有限元软件的强度折减法进行不同降雨条件下的滑坡变形分析，同时引入软弱夹层强度“S”型曲线弱化模型，并优化考虑裂隙水压和渗流力的耦合模型，对比讨论滑坡的稳定系数演化特征。结果表明，滑坡的变形迹象与数值模拟结果得到相互印证，随着降雨持续，变形带由后缘夹层不断向前缘演化扩展；强降雨导致富含黏土矿物的软弱夹层强度弱化是该滑坡失稳的主要原因。通过对比不同方式计算的边坡稳定系数，采用考虑软弱夹层强度“S”型曲线弱化模型计算的滑坡稳定系数随着后缘裂隙水头高度和结构面强度软化阶段表征参数(λL)的增加而快速减小，突出了滑坡变形失稳演化的时间效应，其更适用于滑坡风险评价工作；而采用极限平衡法计算的滑坡稳定系数，突出了计算结果的唯一性，适合于以安全为前提条件的滑坡抢险的风险决策。更多还原

【Abstract】 Rainfall-induced tuff slope containing weak interlayers are the main type of landslides in the south of Zhejiang Province.In order to further understand the impact of different weakening modes of weak interlayers on landslide stability.This study uses the strength reduction method in Midas GTX NX software to analyze the deformation characteristics ofthe typical tuff landslide Chengtian landslide in Songyang county under different rainfall conditions.At the same time, the S-shaped curve weakening model of weak interlayer strength is introduced, and the coupling model considering fracture water pressure and seepage force is optimized.The evolution characteristics of stability coefficient of landslide are compared and disscussed.The results show that the deformation signs of the landslide and the numerical simulation results are mutually confirmed.The deformation zone expands and evolves from the rear edge to the front edgeof weak interlayers during continuous rainfall.The strength weakening of weak interlayers with high clay minerals caused by heavy rainfall is the primary factor leading to the instability of landslide.The stability factors of thelandslideare calculated by the S-shaped curve weakening model of the weak layerwill decrease with the increase of water head in tension cracks and phase characterization values λL,which reflect the time effect of deformation of landslide.The S-shaped curve weakening model of weak interlayer is more suitable for landslide risk assessment.The landslide stability coefficient calculated by the limit equilibrium method highlights the uniqueness of the calculation results, which is suitable for the risk decision-making of landslide rescue on the premise of safety.更多还原