季节冻土区高铁路基保温层稳定作用研究

针对西宁至成都高铁若尔盖湿地段路基工程，基于传热方程、水分迁移方程与力场平衡方程建立季节冻土区高铁路基冻胀的水热力耦合模型，对比分析普通路基和保温路基的温度、水分和位移特征差异。结果表明：保温层有效降低路基的冻胀量，同时减小左右路肩的冻胀量差；保温路基与普通路基的总含水量分布相似，由于保温层将冻结锋面完全阻止在保温层内，其冻深远小于普通路基。

Study on the Stabilization of Insulation Layer of High-speed Railway Subgrade in Seasonal Frozen Region

In relation to the subgrade of Zoige Wetland section of Xining—Chengdu high-speed Railway, based on the heat transfer equation, water migration equation and force equilibrium equation, a thermo-hydro-mechanical coupled model for frost heave of high-speed railway subgrade in seasonal frozen region was established. The difference of temperature, moisture and displacement between ordinary subgrade and thermal insulation subgrade was analyzed. The results show that the insulation layer can effectively reduce the frost heave amount of the subgrade, diminish the difference of frost heave amount between left should and right shoulder. The total water content distribution in the insulated subgrade is similar to that in the ordinary subgrade. However, the freezing front is completely prevented in the insulation layer, so the frozen depth in the insulated subgrade is much less than that in the ordinary subgrade.