摘要
为了有效地分析非饱和成层土的水—力耦合问题,基于非饱和土有效应力原理和渗流理论,考虑降雨过程中双层土孔隙特征及渗透性随应力的动态变化特点,建立了非饱和成层土一维降雨入渗水力耦合模型,利用Flex PDE软件编制计算程序,对一典型双层土降雨入渗模型进行了分析。结果表明,在雨水入渗过程中,上粗—下细型土的分界面处会出现较大的孔隙水压力变化,且耦合、非耦合情况差异明显;上细—下粗型土可不考虑入渗过程中水力的耦合效应;对于上粗—下细型土,短历时强降雨在土层接触带会产生较大的孔隙水压力突变。
In order to analyze the coupling of seepage and stress in unsaturated layered soils, based on the effective stress theory and the seepage theory of unsaturated soil, considering the dynamic changes of pore characteristics and per- meability with the stress state during rainfall, a one dimensional infiltration model of coupled seepage and stress in unsat- urated layered soils was established. And then, a calculating program was written in Flex PDE to analyze the process of rainfall infiltration in a typical double layer soil model. The resuhs show that a significant change of pore water pressure will appear at the interface of coarse over fine soil during infiltration and a great difference exists between the coupled and the uncoupled conditions while the corresponding difference of fine-over coarse soil can be neglected. For a coarse over fine soil, a heavy rain in a short time will cause a great increase of pore water pressure at the interface.
出处
《水电能源科学》
北大核心
2015年第7期66-70,共5页
Water Resources and Power
基金
国家自然科学基金项目(41172280
41272005)
四川省杰出青年学术技术带头人计划项目(2012JQ0007)
四川省教育创新团队项目
关键词
成层性
非饱和土
水力耦合
降雨入渗
layered structure
unsaturated soil
couple of seepage and stress
rainfall infiltration
