连续降雨条件下黄土路基水分场数值分析  

Numerical analysis on moisture migration in loess subgrade under rainfall

作　　者：王铁行[1] 岳彩坤[1] 鲁洁[1] 刘丽萍[1] 

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055

出　　处：《西安建筑科技大学学报（自然科学版）》2007年第5期593-597,共5页Journal of Xi'an University of Architecture & Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(50308024);陕西省自然科学基金资助项目(E208)

摘　　要：基于非饱和土水分迁移模型,给出了考虑含水量和密度影响的非饱和黄土路基水分场计算模型,确定了模型参数.指出含水量和密度对非饱和黄土渗透系数kw均有显著影响.编制有限元程序,模拟不利连阴雨天气,对黄土路基水分场变化过程进行计算分析.揭示出降雨入渗条件下土体密实度对路基水分场的变化有显著影响,密实度越小,路基湿软区域越大,雨水入渗水分迁移进程越快;相同条件下硬路肩较之土路肩更利于防止雨水入渗.因此,采用硬质路肩或增加土体密实度,均有利于减轻雨水渗入路基,从而预防和减少路基水毁病害.Taking the soil density and water content into account, a numerical model of moisture migration in unsaturated loess subgrade is given, and parameters of the model are obtained. It is pointed that the coefficient of water volume change m2^w is not only velated to the moisture content but also to the soil density. So is the Coefficient of permeability kw also related to soil density. Furthermore, by simulating unfavorable rainfall, moisture migration in loess subgrade is studied. The slaking scope in subgrade by seepage is gradually enlarged. The area of the slaking scope is related to loess density, and less density of subgrade loess result in big slaking scope. Building subgrade in greater loess density or using hard shoulder is an advantage to avoid seepage risks.

关 键 词：非饱和土 黄土 路基 渗流 数值分析 

分 类 号：U416.169[交通运输工程—道路与铁道工程]