中文摘要：

利用瞬态剖面法测定重塑黄土试样的非饱和渗透系数。试样取自陕西泾阳县泾河南岸黄土塬上部的马兰黄土。用0.5 mm的筛将风干碾碎的黄土样筛入一高2 m的圆形玻璃桶内，上部补给一定量的水，随后按一定时间间隔量测土柱内不同深度的含水率，再根据土的基本物理指标换算为体积含水率。同时配制与模型桶相同密度的土样，用张力计法测定其土-水特征曲线，即不同体积含水率土样的基质吸力。根据土-水特征曲线和模型桶内体积含水率剖面计算得到不同时刻土样的水头剖面，由此可进一步计算出水分在垂直方向的渗流速度和水力梯度，并得出不同体积含水率土样的渗透系数。通过回归分析，获得渗透系数与体积含水率、渗透系数与基质吸力的函数关系，该函数可用于黄土的非饱和渗流分析。

英文摘要：

The instantaneous profile method is generally applied to determine the unsaturated permeability function. In this paper, a laboratory model of the instantaneous profile is used to determine the permeabili-ty function of unsaturated loess. The loess sample was collected from the typical Malan loess in southern bank of the Jinghe River,near Jingyang County,Shaanxi Province. The grinded loess powder was sieved in-to a 2 meter high glass cylinder,and then it was consolidated with a certain load on the top till stable. A 10cm layer of fine sand was covered on the top of the column to avoid the hardening of loess. As start to do the test, to fill a certain amount of water on the top, the water will penetrate into the loess through sand bed. Water content profiles of the loess column were obtained in certain time by measuring water con-tent at intervals of 5cm along the depth. The sample in the same density with model test was made to mea-sure the soil-water characteristic curve by TEN-15 tensionmeter. Then the soil-water characteristic curve and water content profiles at different time were applied to calculate the water flow rate, the hydraulic head gradient and the unsaturated coefficient. At last, the permeability equation was fitted with exponent function which can apply for seepage analysis of loess.