长春季节性冻土地区土体微观结构与水分迁移的关系

The relationship between the moisture content translocation and the microstructure of seasonal frozen soil

利用扫描电子显微镜（SEM）技术,从土体微观结构特征出发,对长春—吉林公路某路段季节冻土的粒度成分、结构单元体成分、孔隙特征及结构特征进行了定量分析,并对其与水分迁移的关系进行了讨论。从SEM图像定量分析中可以看出,研究路段的土体,其微观颗粒——结构单元体、孔隙的定向性均较差,粒内微小孔隙发育,土体尽管在粘粒含量较高的情况下,也表现出孔隙主要在1～2μm内分布,即毛细孔隙极发育,说明样品具有各向同性的特点,即在外界条件相同的情况下水分迁移的通道在水平和垂直方向上具有相同的性质。

In this paper the microstructure of seasonal frozen soil of the road between Changchun City and Jilin City is studied with the technique of SEM. Quantitative analysis which is about the granularity composition, the characteristic of structure units and pores is carried out, also the relationship between moisture content translocation and microstructure is discussed. It is shows that in the microscopic level the microscopic particles and structure unit have the following features, such as the directionality is not obviously, much more pores is developed in it, and even in the condition of clay content higher, the pore aperture is mainly distributed in the 1-2μm, i.e. the capillary pore is abundant. The resultant shows that the characteristics of soil sample is isotropy, namely the moisture content translocation behavior is same both in horizontal and vertical direction under the same external conditions.