Research on the critical depth migration characteristics of the melting soil slip surface slope in seasonal frozen region

In order to research the shallow landslide hazards of soil slopes in seasonal frozen regions, the critical depth analysis methods are put forward. Continuum explicit finite difference method is applied in the research. Considering the temperature, gravity and seepage force, the soil slope solid model of seasonal frozen regions is established. As the outside temperature alter from -5°C to 10°C, then the unfavorable stress position and failure depth of the fixed water content soil slope of seasonal frozen regions is put forward. Based on the critical depth experiment data of freeze-thawing surface, the safety factor variations of different water content and F-T times are compared. Analysis reveals that, the failure surface is the interface between the frozen and thawed surface in the slope. With the increasing of water content and F- T times, the critical depth migrates to the surface gradually, and finally reaches to the average maximum depth of the region. The conclusion could present more reference of the slope stability analysis and supervision in the seasonal frozen area.