Experimental study on influences of deformation characteristics of salinized silty soil at dam base in northern Xinjiang

For the deformation characteristics of a kind of salinized silty soil widely distributed in the northern Xinjiang area, the compression and humidification deformation tests are carried out. The test results show that the compression characteristics of salinized silty are less affected by dry density and more affected by water content and salt content. When other conditions are constant, the compressive modulus E_s1-2 of the sample is 46.10 MPa when the water content is 7.8%, and that of the saturated sample is 9.75 MPa. When other conditions are constant, the compression modulus E_s1-2 of the saline-washed soil sample is 32.11 MPa, and that of the salt content is 14.89 MPa. On the other hand, the change of salt content under low perimeter pressure has a significant effect on the moisture-enhancing deformation of the salinized silt. In the case of no load, the higher the salt content, the greater the swelling rate of the soil samples, and the presence of sulfate promotes the swelling of the soil. When the consolidation load is greater than 25 kPa, the effects of salt content on the swelling rate change from a positive correlation to a negative one, and at this time the increase in the salt content instead of suppression of the swelling, and even lead to the compression deformation of the soil samples. The correlation analysis shows that, except the overlying stress, the water content is the main influencing factor for the compression characteristics of the salted silt, and the salt content has more obvious influences on the humidification and deformation of the salted chalk.