重塑非饱和黄土中水-气两相运移规律研究  

Water-air two phase migration law of remolded unsaturated loess

作　　者：余娅婷 王大浩 董洁 王玮[1,2] YU Yating;WANG Dahao;DONG Jie;WANG Wei(School of Water and Environment,Chang’an University,Xi’an 710054,China;Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region,Ministry of Education,Chang’an University,Xi’an 710054,China;Shaanxi Institute of Engineering Prospecting(SIEP),Xi’an 710068,China)

机构地区：[1]长安大学水利与环境学院,陕西西安710054 [2]长安大学干旱区地下水文与生态效应教育部重点实验室,陕西西安710054 [3]陕西工程勘察研究院有限公司,陕西西安710068

出　　处：《水资源与水工程学报》2020年第3期228-232,共5页Journal of Water Resources and Water Engineering

基　　金：国家重点基础研究发展计划(973计划)项目(2014CB744702)。

摘　　要：黄土区水分入渗的实质是水、气两相运移共同作用。长时间强降水影响下,水分入渗更易在远离边坡的土层底部形成封闭条件,而在靠近边坡区域形成开放条件。为深入剖析黄土中水-气运移规律,分别在封闭和开放条件下进行了重塑土柱试验,并统计分析了土柱内实测的含水率和气压数据。结果表明:在开放和封闭条件下,湿润锋运移速度初始时最大;体积含水率均为先增大后减小,封闭条件下含水率减小后趋于稳定,而开放条件下含水率仍存在小幅波动;开放条件下气压差先增大后减小,最后在0附近振荡,而封闭条件下浅层气压差波动上升,深层气压差振荡后减小趋于稳定。因此,在滑坡治理过程中应同时考虑水、气两相共同的影响,制定更为全面、高效的防治措施。The essence of water infiltration in loess area is the joint action of water and air migration.Under the influence of heavy precipitation of a long period,moisture infiltration is easier to form a closed condition at the bottom of the soil layer away from the slope,and an open condition is formed near the slope area.In order to analyze the water-air migration law in loess,the remolded soil column test was carried out under closed and open conditions,and the measured data of water content and air pressure in soil columns were statistically analyzed.The results showed that under the open and closed conditions,migration velocity of the wetting front was the largest at the beginning,the volume moisture content increased first and then decreased.The moisture content decreased and then tended to stabilize under the closed condition,whereas the moisture content still fluctuated slightly under the open condition.Besides,under the open condition,the air pressure difference increased first and then decreased,and eventually oscillated near 0.While under the closed condition,the air pressure difference of the shallow layer rose with fluctuations,and that of the deep layer oscillated and then decreased to a stable rate.Therefore,in the process of landslide treatment,the influence of water and air should be considered at the same time to formulate more comprehensive and efficient prevention and control measures.

关 键 词：非饱和黄土 水-气运移 土柱试验 湿润锋 体积含水率 气压差 

分 类 号：TU444[建筑科学—岩土工程]