寒冷地区隧道防冻隔温层厚度计算方法

为确定寒冷地区隧道防冻隔温层的最佳设防厚度,利用等效厚度换算法、气象解析法和有限元模拟计算法,分别对其设防厚度进行计算。由前两种方法计算结果可看出,防冻隔温层设置在初期支护与二次衬砌之间时厚度小于1 cm,设置于衬砌表面时所需厚度小于2 cm,与实际情况比较吻合;由有限元模拟计算法计算的相应结果分别为3.2 cm和4.4 cm,比实际情况偏大;有限元模拟计算法计算结果偏保守,气象解析法计算过程复杂,等效厚度换算法计算过程简单;在工程实际中,防冻隔温层厚度计算可采用等效厚度换算法,为了经济,防冻隔温层适合设置在衬砌中间。

Calculation method of antifreezing layer thickness in cold region tunnel

In order to determine the optimum thickness of antifreezing layer of highway tunnel in cold region,the thickness was computed by separately using equivalent thickness conversion method,weather analytic method and finite element simulation method.Calculation result shows that aimed at former two kinds of methods,the antifreezing layer thickness is less than 1 cm when it lies between the primary support and the lining,and less than 2 cm when it lies on the lining surface,which are consistent with the practice;the relevant values are 3.2 cm and 4.4 cm respectively aimed at finite element simulation method,which are bigger than the thicknesses of antifreezing layer in reality;the result of finite element simulation calculation is excessively safe for the structure,the computation process of weather analytic method is complex,the computation process of equivalent thickness conversion method is easy and can be applied in engineering practice;the antifreezing layer is suitable to be laid between the primary support and the lining to save money.2 tabs,3 figs,10 refs.