辽西地区冻风积土水分迁移特征的研究

对辽西地区的风积土进行了冻结过程的水分迁移试验，获得了含水量随温度和时间的变化规律；基于连续介质力学和热力学理论，建立了冻结过程中水分迁移的动力学模型，并采用差分解法进行了数值模拟分析；借助于扫描电镜从微观上研究了冻结过程中试样内部土颗粒的排列变化，从而揭示风积土的水分迁移特征。研究结果表明：时间和温度决定了水分迁移的充分性，温度的变化随深度的增加而具有衰减性，并且在冻结峰面附近形成一个冻结含水量峰值；在靠近顶端的一定深度内，冻结后的含水量并没有持续增加，反而有减小的趋势；通过扫描图像可以看出，土颗粒的重新排列直接反映了水分迁移的状态。

Study on moisture transfer of freezing aeolian soil in West Area of Liaoning Province

Aiming at the aeolian soil in the West Area of Liaoning Province, the moisture transfer of the freezing process is tested; and the change law of moisture content with time and temperature are obtained. A dynamic coupling model of moisture transfer in the freezing process is established based on the theories of continuum mechanics and the thermodynamics; and the numerical simulation analysis is studied by using difference method. From microscopic viewpoint, the permutation of soil grain is studied via the scanning electron microscope, which reveals the moisture transfer characteristic of aeolian soil. The results indicate that a peak of frozen moisture content is formed in frozen peak surface, which is developed for depth change with time increased. Time and temperature decide the sufficiency of moisture transfer, and the change of temperature wane with the increment of depth. From scanning pattern, we can draw that the fresh arrange of soil grain directly reflects the state of moisture transfer.