Laboratory research on relationship between swelling force and allowable deformation

In order to understand the differences of swelling forces tested by three conventional methods and discuss the swelling force attenuation law with allowance of a small amount of swelling deformation, the swelling force tests of Baise expansive soil were carried out by anti-inflation pressure method using uniaxial oedometer. In addition, the swelling force tests with allowance of deformation base on the same principle of pressure expansion method were performed. The results of swelling force on the samples with two water contents and the same dry density indicated that the maximum, medium and minimum of swelling force were tested by swelling anti-pressure method, the balance pressure method and the pressure expansion method, respectively; In addition, the relationship between swelling force and expansion deformation was a negative exponential; The increase in water content of the expensive soil during practical conditions was restrained by the overburden pressure. The research results can provide the references for reasonably choosing the swelling force testing methods and the design of the expansive soil subgrade.