季节性冻土区隧道温度场分析与预测

Analysis on and Prediction of Temperature Field of Tunnels Located in Seasonal Frozen Area

为预防季节性冻土区隧道因防寒保温措施设置不足引发的冻害,研究季节性冻土区吐库二线中天山隧道温度场变化规律及其防寒保温参数。基于围岩温度场现场测试研究,利用ANSYS有限元软件,同时考虑水文地质条件、混凝土衬砌水化热、大气温度和地温随时间变化等影响因素,预测、比较隧道施加保温层和未施加保温层的冻融循环圈。总结出设置保温边沟和设置厚度≥5cm、导热系数≤0.03 W/(m·K)的保温层是必要和合理的。

The temperature field variation rules and thermal retardation parameters of Zhongtianshan tunnel on Turpan- Korla railway located in seasonal frozen area are studied, so as to avoid damages caused by insufficient thermal retarda- tion countermeasures. Prediction and comparison and contrast are made on the freezing-thawing cycle ring of tunnels with and without thermal retardation layers, by means of ANSYS FE software and on basis of field tests on the temperature field of the rock mass, with such influence factors as the hydrogeology conditions, the hydration heat of the concrete lin- ing, the atmospheric temperature and the ground temperature being considered. It is concluded that it is necessary to in- stall thermal retardation side ditches, as well as thermal retardation layers with their thickness being more than 5 cm and their thermal conductivity being smaller than 0.03 W/（ m - K）.