多年冻土区水泥混凝土路面下冻土路基温度场数值分析

Numerical Simulation of Thermal Field of Roadbed under Cement Concrete Pavement in Permafrost Region

运用abaqus有限元分析方法,对不同冻土断面类型,不同路堤高度的水泥混凝土路面路基温度场进行了数值模拟,计算结果与观测结果比较后证实有限元模型参数的选取和计算方法是正确可靠的。通过分析可以得出以下结论:在相同冻土断面地区,水泥路面基底融深较沥青路面下基底融深浅,体现了较好的热稳定性;不管何种冻土断面及路面类型,随着所处环境气温的升高,路面基底年最大融深均有所增加,沥青路面基底融深对中低温冻土地区气温升高的响应迅速,水泥路面基底融深对高温冻土地区气温的升高响应迅速;对于中低温多年冻土段水泥路面的大致路堤临界高度为1.2 m,对于高温不稳定多年冻土段,路堤临界高度在1.6 m左右,对于高温极不稳定多年冻土段,路堤临界高度在2.1 m左右。

Roadbed thermal field cement concrete pavement with different heights of embankment and different cross-section types of permafrost were simulated by ABAQUS. The correctness and reliability of the selection and calculation method of parameters of FE model were validated by comparison between the simulation result and measuring result.Through analysis, conclusions are reached that （1） the embankment permafrost stabilization of cement concrete pavement is better than that of asphalt concrete pavement; （2） no matter what types of permafrost and pavements, the annual permafrost tables under embankments increase with temperature rises, permafrost tables under embankments with asphalt concrete pavement respond rapidly to medium/low temperature permafrost region, while permafrost tables under embankment with cement concrete pavement respond rapidly to high temperature permafrost region; （3） the critical heights of cement concrete pavement embankment in medium/low temperature permafrost region, shaky high temperature permafrost region and extremely shaky high temperature permafrost region are 1.2 m, 1.6 m and 2.1 m respectively.