土壤吸湿-湿过程中水力传导度的拟合研究

Study on Simulation of Hydraulic Conductivity in the Soil Desorption-absorption Processes

非饱和含水介质在吸湿和脱湿的不同过程中,水力传导度随介质含水率的变化规律是不同的。本文选取大沽河流域两种代表性砂土,对其吸湿-脱湿两个过程分别进行试验观测,并使用Van Genuchten-Mualem模型对其吸湿-脱湿过程进行水力传导度的拟合。研究结果表明:砂土在吸湿过程的非饱和水力传导度与脱湿过程的非饱和水力传导度大小并不相同,在含水率相同的情况下,吸湿过程的水力传导度要比脱湿过程大,在含水率较低时(小于15%)相差可达1个数量级。

In desorption and absorption processes, the hydraulic conductivities of unsaturated water - bearing media are not identical. We selected two kinds of representative sandy from the Dagu River, observed the course, used Van theGenuchten - Mualem model to The results showed that the hydraulic conductivity in simulate the hydraulic conductivity in the two Processes. absorption process and the hydraulic conductivity in desorption process, moistureabsorption process are not to be certainly same. In the same moisture content, the absorbing conductivity is greater than the desorbing conductivity, and the differenceto is possible to reach 1 magnitud when the moisture content is smaller than 15% ）.