摘要
为了分析强降雨条件下粗粒土高路堤边坡的稳定性,基于渗透力理论,对边坡在强降雨条件下的二维渗流特性进行计算,然后,通过Fish语言编程,将边坡孔隙水压力和渗透力等渗流参数导入FLAC3D软件中,重点分析渗透力变化对路堤边坡稳定性的影响。研究结果表明:在强降雨条件下,路堤边坡在X方向的渗流梯度在边坡表面及第二级边坡坡脚处表现为正值,坡脚处包络线所包围的正值区域逐渐向边坡内部扩展,边坡坡顶处在X和Y方向的渗流梯度的变化幅度较大;路堤边坡表层孔隙水压力随降雨入渗持续而逐渐增加,随雨水的不断渗出而逐渐减小;路堤边坡坡顶处体积含水率呈现"凸"型分布,边坡纵截面体积含水率呈现"凹"型分布;随着雨水持续入渗,路堤边坡塑性区首先在各级边坡坡脚处及第二级边坡坡脚下方形成,并逐渐沿坡顶方向向边坡内部扩展,形成塑性贯通区;受渗透力的影响,边坡安全系数演变规律分为缓慢上升阶段、缓慢下降阶段、快速下降阶段和缓慢回升阶段。
In order to analyze the stability of coarse grained soil with high embankment under strong rainfall condition,two-dimensional seepage characteristics of slope under heavy rainfall conditions were calculated based on the penetration theory.The seepage pore water pressure and seepage force were imported into FLAC3D software by Fish language programming.The impact of the change of seepage force on the stability of embankment slope was analyzed.The results show that under strong rainfall conditions,the seepage gradient of embankment slope in X direction is positive on the surface of the slope and at the foot of the second grade slope.The positive area surrounded by the envelope of the slope foot gradually extends to the interior of the slope,and the rate of change of the seepage gradient in X and Y directions at the top of the slope is larger.The pore water pressure on the surface of the embankment slope increases gradually with the infiltration of the continuous rainfall,and gradually decreases with the continuous exudation of the rain water.The volumetric water content of embankment slope top shows“convex”distribution,and the vertical section of the slope shows“concave”distribution.With the continuous infiltration of rainwater,the plastic zone of embankment slope is firstly formed at the foot of slope and at the foot of the second grade slope,and gradually extends to the interior of the slope along the top of the slope to form a plastic penetrating zone.Influenced by the seepage force,the evolution law of slope safety factor is divided into 4 stages,i.e.slow rising stage,slow decline stage,rapid descent stage and slow recovery stage.
作者
段旭龙
何忠明
王保林
DUAN Xulong;HE Zhongming;WANG Baolin(School of Geosciences and Info-Physics,Central South University,Changsha 410083,China;School of Traffic and Transportation Engineering,Changsha University of Science&Technology,Changsha 410114,China)
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2018年第8期2016-2023,共8页
Journal of Central South University:Science and Technology
基金
国家自然科学基金资助项目(51508042
51678073)~~
关键词
强降雨
粗粒土
稳定性
渗透力
安全系数
strong rainfall
coarse grained soil
stability
seepage force
safety factor
