Influences of freezing-thawing actions on mechanical properties of soils and stress and deformation of soil slope in cold regions.

Freezing-thawing actions can affect the mechanical features of soil greatly, which is vital for the stability of soil slope in cold regions. Firstly, triaxial compression tests on sand samples under undrained conditions were performed to investigate the influences of freezing-thawing cycles, which shows that the freezing-thawing actions can weaken their strength and stiffness, and with the increasing freezing-thawing cycles, both the deviatoric stress and pore water pressure decrease gradually. Then, the double hardening constitutive model was revised to model the influences of freezing-thawing cycles in consideration of the influences of freezing-thawing actions, and the model was also validated by the test results. Finally, the proposed constitutive model was incorporated into a finite element code to numerically simulate the distribution of displacement and pore water pressure of sand slope subjected to freezing-thawing cycles, which shows that the freezing-thawing actions accelerate the dissipation of the pore water pressure and enlarge the displacement of the slope. The study here can provide a help in designing and construction of civil engineering in cold regions.