降雨自由入渗阶段试验研究及其过程的水势描述  

Potential description of rainfall free infiltration phase

作　　者：王建新[1] 王恩志[1] 王思敬[1] 

机构地区：[1]清华大学水利水电工程系,水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《清华大学学报（自然科学版）》2010年第12期1920-1924,共5页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金资助项目(40872152);“十一五”国家科技支撑计划项目(2006BAK30B02)

摘　　要：研究降雨自由入渗阶段土体内的水势变化规律具有重要的工程意义。讨论了现有的入渗模型及降雨非饱和渗流计算方法。认为其不能满足工程渗透稳定性分析的需要,且不符合实际的降雨物理过程。设计了室内降雨自由入渗负压测试试验,结果显示:土体负压在入渗阶段的变化规律符合Boltzmann函数曲线,降雨强度越大负压值变化越快。结合土壤水能态理论,分析了自由入渗阶段土体内水势的变化和分布规律,并指出非饱和渗透系数随着降雨强度的增大而增大。该研究为低降雨强度条件下岩土工程的渗透稳定性问题的分析提供了参考依据。Suction variations during free infiltration greatly affects the flow properties.Existing infiltration models and unsaturated rainfall seepage numerical methods can not solve geological engineering seepage stability problems,and do not accord with the actual rainfall infiltration phase.Indoor rainfall free infiltration tests were used to measure the suction variations which accord with the Boltzmann function,with greater rainfall intensity leading to the faster suction changes.Soil water potential theory was then used to describe the free infiltration phase with a greater rainfall intensity leading to a greater unsaturated coefficient of permeability.This research provides a reference for engineering seepage for small rainfall intensities.

关 键 词：降雨入渗 自由入渗阶段 负压 非饱和渗透参数 

分 类 号：TU433[建筑科学—岩土工程]