Test Research On Characteristics Of Soil-Water And Swelling-Shrinkage Deformation Of The Compacted Expansive Soil Under The Drying-Wetting Cycle Action

During the process of the fast development of infrastructure construction in China, engineering disasters caused by expansive soil come to be the prominent problems for geotechnical engineering. So doing research about the characteristics of expansive soil which the volume always changes with the water content is of significance.In this paper, soil sample mixed by sand and expansive soil located at Gao Miaozi is researched by laboratory tests including filter paper method test and wetting-drying test. And from the tests, characteristic curves of water and soil, and curves of moisture expansion and drying shrinkage are researched in the direction of drying and watering cycle condition, and the angles of vertical stress.Based on the above, Fredlund & Xing mathematical model is applied for matching characteristic curves of water and soil to establish the characteristic equation of this soil sample. And for getting the calculation expression of the volume changing, the swell-shrink constitutive model of compacted expansive soil is applied analyze swell-shrink deformation. Hope to enhance the research of the water holding capacity and swell-shrink deformation of expansive soil.