寒区隧道的抗冻措施研究对隧道建设有重要意义，基于对流-导热耦合作用的非稳态传热有限差分计算模型，计算分析寒区隧道多年冻土和非冻土段外贴式及中隔式保温隔热层的保温隔热效果，并对寒区隧道纵向铺设保温隔热层后的抗冻效果展开研究。结果表明： 1)在非冻土地层外贴式保温层保温效果较佳，在多年冻土地层中隔式隔热层隔热效果较佳，两者效果相差不大； 2)受周期性入口风温的影响，隧道衬砌背后温度呈现周期性变化，变化幅度逐年递减。在材料、施工允许的前提下，建议采用外贴式保温隔热层； 设计时，保温隔热层厚度应作经济技术比选。本文研究成果可供寒区隧道设计者与研究者参考。

The study of heat preservation methods for tunnels in cold region is very important. As a result, a unsteady heat transfer finite difference calculation model is established based on convectionconduction interaction; the heat preservation and insulation effect of surface and sandwich heat preservation and insulation layer on sections of tunnels with and without permafrost is calculated and analyzed respectively; and the antifreezing effect of heat preservation layer along longitudinal direction of tunnel is studied. The results show that: 1) The surface heat preservation and insulation layer has a good effect on tunnel section without permafrost, while the sandwich one has a good effect on tunnel section with permafrost; and the heat preservation and insulation effects of these two kinds of layers vary little. 2) The temperature behind the tunnel lining shows periodic variation due to the influence of wind temperature, and the temperature variation range decreases over years. It is proposed that the surface layer should be adopted preferentially; and economical comparison should be made in design phase. The results can provide reference for design of tunnels in cold region in the future.