Abstract:In cold regions, coarse-grained soil is the main filler for subgrade, earth-rock dam and other projects, and is also widely distributed on slopes in alpine regions. The subgrade of high-speed railway in cold region has frost heave deformation in winter, and the high-altitude slope of coarse-grained soil has collapsed in spring. The prevention and evaluation of disasters are closely related to the mechanical properties of coarse-grained soil under freezing and thawing. Therefore, a large number of domestic and foreign documents had been consulted. The research status of coarse-grained soil mechanics in cold regions was reviewed from the aspects of constitutive relations, physical properties, mechanical properties and interface problems. The results show that new constitutive models of coarse-grained soil considering the dilatancy, particle breakage, nonlinearity and freeze-thaw effect have been established by introducing different new theories. In-depth research has been carried out on the basic physical properties, water-physical properties, thermophysical and electrical properties of coarse-grained soils in cold regions. Then, the shear strength, deformation law and factor action mechanism of coarse-grained soil under different factor levels, stress conditions and temperatures are studied systematically. These studies are carried out through research methods such as large-scale direct shear test, large-scale triaxial compression test, numerical simulation and theoretical analysis. The shear properties of coarse-grained soil-structure interface, freeze-thaw interface and their relationships with the slope stability are deeply discussed. Finally, according to the current research status, the study prospect on the mechanical properties of coarse-grained soil in cold regions is analyzed.