关键词: 膨胀土, 干燥收缩, 初始条件, 收缩特征曲线, 水泥固化

Abstract: Expansive soil is a kind of typical soil with problems, which is very sensitive to climate change. it is prone to volumetric
shrinkage deformation under drought conditions, causing various engineering geological problems. In order to study the desiccation
shrinkage deformation characteristics of expansive soil, a series of indoor drying experiments were carried out to determine the
shrinkage characteristic curves of expansive soils, and the effects of initial moisture content and dry density on the shrinkage
deformation process were mainly analyzed. The effect and mechanism of cement solidification on suppressing desiccation shrinkage
deformation of expansive soil are further discussed. The results show that: (1) There are three typical stages in the shrinkage
deformation process of expansive soils: normal shrinkage, residual shrinkage, and zero shrinkage. (2) The higher the initial moisture
content, the faster the evaporation rate of the sample, and the smaller the void ratio of the sample after the shrinkage deformation is
complete, and the larger the final shrinkage strain, the more obvious the shrinkage deformation will be. (3) The larger the initial dry
density, the smaller the sample evaporation rate and the final volume shrinkage strain, and the increase of the initial dry density has a
significantly reduce the volumetric shrinkage strain of the sample, and it has a good suppressive effect on shrinkage deformation. (5)
The dry shrinkage deformation of expansive soil has obvious anisotropic characteristics and is related to the initial state.
certain inhibitory effect on the shrinkage deformation of the sample. (4) Incorporating proper amount of cement in expansive soil can

Key words: expensive soil, desiccation shrinkage, initial conditions, shrinkage characterization curve, cement solidification