粉粘土夹层对砂的减渗规律试验分析

Experimental Analysis on the Infiltration Reduction Rule by Clay Interlayer in Sand

对高渗透性砂内部的低渗透性粉粘土夹层的减渗作用进行了室内垂直一维入渗试验研究。通过分析累计入渗量I、累计入渗时间t、湿润锋推进距离z之间的关系,定性阐述了粗砂中的粉粘土夹层的减渗作用,其结果表明:粗砂中的粉粘土夹层使水的入渗率和湿润锋的推进速度明显减小,并且将均质中的非线性入渗过程变为夹层内的线性入渗过程,使夹层范围的入渗成为一个具有较小入渗率和较小湿润锋推进速度的稳渗阶段。

The function of infiltration reduction by clay interlayer in saner was carried out oy onedimentional infiltration experiments in lab. By analyzing the relationship among the cumulative infiltration volume （I）, cumulative infiltration time （t） and the advanced wetting distance （ z ）, this paper qualitatively expounds the effect of infiltration reduction by clay interlayer in sand. The results have shown that the clay interlayer can obviously reduce the infiltration rate and advanced wetting velocity and convert the non-linear process into the linear infiltration process and thus resulting in the stable infiltration process in clay layer with a smaller infiltration rate and a smaller wetting velocity.