中文摘要：

应用CT扫描技术对两种稳定非饱和状态的砂土试样分层进行扫描,得到不同深度CT扫描层图像,采用Image J图像处理软件将CT图像转化为CT数均值,然后在稳定非饱和试样中分别间断性连续注入污染物KI溶液,测定不同时间间隔CT扫描图像,计算注入污染物先后扫描图像结果的差值,建立CT数均值和污染物迁移之间的关系,研究污染物在非饱和砂土中的运移特征,得出非饱和砂土中污染物浓度随时间和深度的变化规律,对研究其他介质中污染物的迁移具有重要的指导作用。

英文摘要：

The computerized tomography（CT） is applied to obtain CT images at different depth of the stable unsaturated sand specimen by scanning each layer of the specimens.The CT images are transformed into mean CT values by the Image J software.This paper also introduces a new CT method to study pollutant migration in unsaturated sand by scanning the specimens,in which the pollutant potassium iodide（KI）solution are injected by the interval continuous method.CT images are measured with different time interval at each depth.The migration characteristics of KI solution in unsaturated sands are examined by calculating the image difference values between after and before injecting pollutant,and the relationship is established between the mean CT value and the pollutant migration in corresponding layer in two different kinds of unsaturated sands.The research results showing the change in pollutant concentration with time and depth are obtained.The computerized tomography is a feasible method for studying pollutant migration in other medium.