设注水孔条件下湿陷性黄土试坑水分入渗规律

Study on water infiltration law of test pits of collapsible loess with water injection holes

对山西省晋中市榆次区大厚度自重湿陷性黄土场地进行布设注水孔、埋设土壤水分传感器的浸水试验。结果表明:由于布设注水孔,试坑内水分扩散存在自下而上、自上而下、由试坑中心向两侧扩散的特点,湿润锋扩散形态比较复杂;浸水52 d,试坑内探井全断面基本达到饱和含水率,注水孔的布设节省了大量的试验时间与费用。体积含水率随时间变化曲线基本可以分为4个阶段:初期含水率平稳段;含水率增长、变化段;饱和含水率稳定延续段;末期含水率小幅减小变化段。

Submerging tests with setting water injection holes and sensors,like moisture meters,were set up on a large-thickness self-weight collapsible loess field in Yuci District,in Jinzhong City,Shanxi Province. The results show that the diffusion pattern of the wetting front is rather complicated due to the feature of moisture spreading in test pits from the bottom up,from the top down,and from the center to the two sides because of setting water injection holes. After 52 days of immersion,the whole section of exploratory wells basically reached saturated water content in the test pits. The layout of water injection holes saved a great deal of time and cost of the experiment.The curve of volumetric water content changing with time can be divided into four stages： the early stable stage of volumetric water content,the growth and change stage of volumetric water content,the steady and extended stage of saturated water content,the late and slightly decreasing stage of volumetric water content.