摘要
降雨入渗是诱发边坡失稳的重要因素之一,准确评估其对边坡稳定性的影响具有重要的工程意义。然而,现有研究多集中于二维模型分析,或忽略降雨入渗过程中土体强度的削弱作用,难以全面揭示降雨型滑坡的失稳机制。文章基于Mein-Larson入渗模型及光滑粒子流体动力学(smoothed particle hydrodynamics,SPH)方法,构建了三维降雨型滑坡模型,分析了不同入渗深度下滑面演变过程,定量评估了降雨入渗对边坡稳定性的影响,系统研究了降雨入渗条件下边坡稳定性的演化特征。结果表明:(1)边坡稳定系数与入渗深度呈负相关,入渗深度增加时,边坡稳定性显著降低;(2)由于浸润线两侧土体性质差异,纵向剖面中滑面演变为不对称复合形态,横向剖面中位移区演变为两个相交的半椭圆形位移区;(3)降雨型滑坡失稳是一个渐进过程,表层饱和土体先局部失稳,随后通过应力重分布引发深层土体变形,最终形成贯通滑面导致整体失稳。
Rainfall infiltration is one of the key factors triggering slope instability.Accurately assessing its impact on slope stability is of great engineering implications.However,existing studies mostly focus on two-dimensional models or overlook the weakening effect of soil strength during rainfall infiltration,making it difficult to comprehensively reveal the instability mechanisms of rainfall-induced landslides.In this study,based on the Mein-Larson infiltration model and the smoothed particle hydrodynamics(SPH)method,a three-dimensional model of rainfall-induced landslides was developed to analyze the evolution process of slip surfaces at different infiltration depths.The study quantitatively evaluates the impact of rainfall infiltration on slope stability and systematically investigates the evolution characteristics of slope stability under rainfall infiltration conditions.The results indicate that:(1)the slope safety factor negatively correlates with infiltration depth;as infiltration depth increases,slope stability significantly decreases;(2)due to differences in soil properties on either side of the wetting front,the slip surface in the longitudinal profile evolves into an asymmetric composite shape,while in the transverse profile,the displacement zone develops into two intersecting semi-elliptical displacement zones;(3)the instability process of rainfall-induced landslides is gradual,beginning with localized instability in the saturated surface soil,followed by deep soil deformation caused by stress redistribution,ultimately leading to the formation of a continuous slip surface and overall slope failure.
作者
肖乐远
刘鹏
任逸
刘航
胡嫚
XIAO Leyuan;LIU Peng;REN Yi;LIU Hang;HU Man(College of Engineering and Technology,Southwest University,Chongqing 400715,China)
出处
《中国地质灾害与防治学报》
2025年第6期12-22,共11页
The Chinese Journal of Geological Hazard and Control
