Shrinkage deformation test of soil based on digital image processing

The change of water content in the evaporation process will cause the shrinkage deformation of the soil, especially the clay soil with more hydrophilic minerals. The change of water content has a significant effect on its mechanical properties. By controlling the relative humidity of the environment room, the dry shrinkage deformation test of the soil was carried out to explore the influence of the change of water content on the dry shrinkage deformation of the soil, especially the cohesive soil. The conclusions are as follows: The changes of axial strain &epsilon;^a and radial strain εr of soils with different properties with time and saturation mainly occur in the first-stage relative humidity environment. The εa of SmC and DCs increases approximately linearly when Sr > 90 %. When Sr < 90 %, the εa of SmC and DCs increases slowly with the decrease of saturation. The εa of ZS increases approximately linearly when Sr > 96 %, and then remains stable. When Sr < 30 %, it increases slightly, and the increase amplitude is only 0.17 %. The overall trend of εr of SmC, ZS and DCs with saturation is similar to that of εa.