黏质粉土冻胀过程中水分重分布和密度变化规律

为了探究黏质粉土冻胀过程中水分重分布和密度变化规律,通过4个不同顶板温度条件下黏质粉土的单向冻结试验,采用切层法和计算机断层扫描(CT)对试样冻结前后的分层含水率数据和分层密度数据进行了分析。结果表明:试样冻胀是由水分迁移和初始土样中的水分重分布后在已冻区和冻结缘区域发生相变后体积膨胀所控制的;试样冻胀后已冻区密度减小,未冻区密度增大,与含水率的变化规律相反。整体试样的宏观冻胀包含了已冻区的冻胀作用和未冻区的固结作用。

Water Redistribution and Density Change of Clayey Silt in the Process of Frost Heaving

In order to explore the water content redistribution and density change in the frost heave process, four samples under different top cold temperature were performed based on the one-dimensional freezing experiment in an open system. The water contents, Computed Tomography (CT) scanning pictures and dry density in different height of the samples were analyzed. The results showed that the frost heave amounts of the samples were controlled by the water absorbed process and the redistribution of the water content from the unfrozen to frozen zone. After the tests, the dry density increased in unfrozen and decreased in frozen zone, which had the opposite law with the water content change.