摘要
为研究降雨和库水位变动共同作用对均质土石坝坝坡稳定特性的影响,基于非饱和渗流原理,选择不同降雨强度、降雨类型(3种)及库水位升降速率,对土石坝坝坡稳定情况进行有限元模拟,结果表明:①无降雨水位变动时,水位变动速率主要影响上下游坝坡安全系数趋于稳定的时间,下游坡安全系数变化幅度整体要小于上游坝坡;②不同强度降雨和库水位变动同时作用时,降雨强度对上游坝坡的安全系数影响较小,上游坝坡最危险工况为水位下降4 m/d+40 mm/d降雨,安全系数为1.298,下游坝坡最危险工况是水位上升4 m/d+40 mm/d降雨,安全系数为1.443;③不同类型降雨和库水位变动共同作用时,此时坝坡稳定分析可分为3个阶段,各阶段安全系数变化随降雨类型呈现出复杂的变化特性。该研究成果为正确认识降雨联合库水位变动下的土石坝坝坡稳定性规律提供参考。
To study the influence of rainfall and the variation of reservoir water level on the stability characteristics of earth rock dam slope,based on the principle of unsaturated seepage,this paper conducts the finite element simulation of dam slope stability under different rainfall intensities,different rainfall types(three in total)and different variation rates of reservoir water level.The results show that:①When there is no rainfall,the variation rate of water level mainly affects the time when the safety factor of upstream and downstream dam slopes tends to be stable,and the variation range of safety factor of downstream dam slope is smaller than that of upstream dam slope.②When the different intensities of rainfall and the variation of reservoir water level occur simultaneously,the influence of rainfall intensity on the safety factor of upstream dam slope is small.The most dangerous condition of upstream dam slope is that the water level falling rate is 4 m/d and the rainfall intensity is 40 mm/d,and the safety factor is 1.298;while that of downstream dam slope is that the water level rising rate is 4 m/d and the rainfall intensity is 40 mm/d,and the safety factor is 1.443.③When different types of rainfall and the variation of reservoir water level occur simultaneously,the analysis of dam slope stability can be divided into three stages,and the safety factor changes with the rainfall type at each stage presents complex characteristics.The study provides a reference for correctly understanding the stability law of earth rock dam slope under different intensities and types of rainfall combined with the variation of reservoir water level.
作者
梁羽凯
LIANG Yukai(Jiangsu Ocean University,Lianyungang 222000,China)
出处
《人民珠江》
2021年第1期84-92,共9页
Pearl River
关键词
土石坝
水位变动
降雨强度
降雨类型
坝坡稳定
earth rock dam
variation of water level
rainfall intensity
rainfall type
dam slope stability
