Analysis On Temperature Field And Slope Stability Analysis Of High Fill Embankment In Seasonal Frozen Area

Site test, theoretical and numerical analysis are used to study the temperature field of freezing and thawing soil , stress-strain field, as well as the influencing factors of slope stability of D3K692+935 stability-testing cross-section of Harbin-Dalian Passenger Dedicated Line. Main contents are as follows:⑴With the observation data of geothermal, temperature and soil pressure of the D3K692+935 stability-testing cross-section of Harbin-Dalian Passenger Dedicated Line, the dissertation expounds the corresponding relation of soil temperature and air temperature and the change rule of soil temperature of different depth with changes in air temperature.⑵This dissertation formulates the control equation of unsteady-state temperature field for the embankment with phase-change in the seasonal frozen soil area, based on which three calculations are made about the temperature field at the toe of slope after thawing cycles in three different conditions. At the same time the development trend of the temperature field in the process of frost heaving and thaw in the actual condition is calculated. Through comparison of the calculation, it is explained that whether the choice for the thickness of non-frost heaving filler and insulation measures are suitable.⑶The coupling between temperature field and stress field is realized through adding steady-state temperature field data to the calculation model of embankment structure as an initial condition. Strength reduction method is adopted to study the slope stability of the embankment in thaw period. Protective effect to the slope is analyzed according to different conditions through comparison of safety coefficient of the slope and analysis of contrast curve of displacements of the feature points with or without slope protection, or geogird. Then the most suitable engineering measures for the embankment are concluded after a comprehensive analysis.⑷According to safety coefficient of the slope with different laid length and distance and contrast curves of the feature points from numerical calculation, the most appropriate geogrid laid scheme is settled in the end.