Xiaowen LIU;
Zeming WU;
hailin luo;
In landfill foundation treatment, high-level radioactive waste disposal, geothermal resources development and utilization and other engineering construction practice, there is a large amount of unsaturated soil. When unsaturated soil is affected by sunlight, geothermal, nuclear waste, biochemical reaction and other thermal radiation, it will accelerate the settlement and deformation of soil temperature. The building structure based on unsaturated soil will also be affected, so it is of great significance to study the influence of temperature on the stress and deformation of unsaturated soil. In this paper, by extending the SFG model of unified yield surface to consider the influence of temperature change on unified yield surface, a yield surface constitutive model which can reflect temperature-suction-stress at the same time is proposed.In order to verify the applicability of the model, triaxial tests on Jiangxi laterite at different temperatures are carried out to determine the parameters needed for model calculation. The model fitting results are obtained by using the test parameters and compared with the test results. With reference to the experimental data of remolded clay used in the literature by Uchaipichat et al, the model was fitted and analyzed. The results show that the unified yield surface SFG model considering the effect of temperature can better reflect the stress-strain characteristics of soil during compression rebound, dehumidification and shear, and verify the reliability of the constitutive model to reflect the stress-strain characteristics of soil at different temperatures, thus further enriching the constitutive theory of unsaturated soil under the influence of temperature.
