邯郸非饱和膨胀土的干燥收缩试验研究  

Experimental Study on Drying Shrinkage of Unsaturated Compacted Expansive Soils

作　　者：高春华[1] 张庆伟[1] 

机构地区：[1]安阳师范学院土木建筑工程系,河南安阳455000

出　　处：《建筑科学》2010年第1期43-46,共4页Building Science

基　　金：河南省教育厅自然科学资金资助(2009B130001)

摘　　要：基质吸力和净平均应力的增大均可引起土体的压缩变形。针对物理性质不同的4种非饱和膨胀土体结合试样收缩曲线和土水特征曲线分析了土体干燥过程中基质吸力和孔隙比的关系。试验结果表明:土体干燥收缩过程中随着基质吸力的增大试样不断发生收缩,当基质吸力增大到某一定值时,基质吸力的增大对试样收缩变形无明影响,称此基质吸力为缩限吸力。并且不同性质土体的缩限吸力不相同,缩限吸力值与土体的塑性指数密切相关。在干燥收缩过程中,当试验的饱和度减小到85%时试样完成了绝大部分收缩,当试验饱和度达到70%时土样的孔隙比基本保持不变。Compressive deformation of soils can be caused by the increase of both matrix suction and net mean stress. Relationship between the matrix suction and the void ratio on drying path is established for four types of unsaturated expansive soils by utilizing the shrinkage curves and the soil-water characteristic curves determined through experimental tests. It is indicated that during the process of drying, the soil samples continuously shrink with the increase of matrix suction. Once the matrix suction increases to a given value, the increase of the matrix suction will not display obvious effect on the shrinkage deformation of the soil samples, the shrinkage of the soil samples is almost fulfilled when the degree of saturation of the soil samples decreases to 85% , and the void ratio of the soil samples is almost kept unchanged when their degree of the saturation of soil is reduced to 70%.

关 键 词：非饱和 膨胀土 基质吸力 收缩曲线 土水特征曲线 饱和度 

分 类 号：TU411.91[建筑科学—岩土工程]