Aimed at the typical soil—silty clay,along Lanzhou metro lines in construction and taking account of influence of soil moisture,its dry density,cold-end temperature,and subjected load on frostheave and thaw settlement of the soil in both open and closed system,the frost-heaving and thaw settling feature of this soil was investigated under artificial freezing condition and the variation rule of the frost heave ratio and thawing settlement coefficient was analyzed under condition of single factor.Experiment r...