基于地气耦合模型的多年冻土区宽幅路基温度场数值模拟  

Numerical Simulations of Temperature Field for Wide Subgrade in Permafrost Regions Under Earth-atmosphere Coupled System

作　　者：汪双杰[1] 崔福庆[1,2] 陈建兵[1] 刘志云[2] 金龙[1] 

机构地区：[1]中交第一公路勘察设计研究院有限公司,陕西西安710075 [2]长安大学地质工程与测绘学院,陕西西安710054

出　　处：《中国公路学报》2016年第6期169-178,共10页China Journal of Highway and Transport

基　　金："十二五"国家科技支撑计划项目(2014BAG05B03);中国博士后科学基金项目(2014M560739)

摘　　要：为了揭示地气温影响下青藏高原多年冻土区宽幅路基内的复杂耦合换热机理,针对典型工况条件下冻土路基内温度场的分布特征及其随时间的变化规律开展了数值研究。将冻土路基的外部环境影响纳入研究模型,通过建立统一的地气耦合系统的二维非稳态计算模型,分析了路面宽度、风速、路基高度和走向等因素对冻土路基各表面温度年际变化特征的影响规律。研究结果表明:路基各表面的温度均大致呈正弦变化趋势,其中沥青路面始终保持较高温度,而天然地表温度在5月上旬和10月上旬出现明显阶跃变化;随着路面宽度的增加,路基各表面的年平均温度随之增加,而随着风速及路基高度的增加而降低,其中尤以沥青路面及两侧土路肩处的降低趋势最为明显;路基边坡处的年均温度与路线走向密切相关,在3种路线走向中,东西走向路基的右侧坡面和左侧坡面年平均温度分别出现最大值和最小值。To reveal the complex coupled heat transfer mechanism of wide subgrade in permafrost regions of Qinghai-Tibet Plateau（QTP）under the influence of the ground and air temperature,the spatial and temporal distribution characteristics of temperature field within the permafrost subgrade under typical working conditions were simulated by the numerical method.A twodimensional unsteady model with uniform earth-atmosphere coupled system considered the surrounding air environment was developed,and the influences of the system parameters,such as the pavement width,wind speed,roadbed height and route trends,on the annual change characteristics of surface temperatures were analyzed.The results show that temperatures of surface regions generally exhibit a periodic sinusoid trend.Among which,the temperature of asphalt pavement keeps the relatively high value and the natural ground surface has an abrupt step change in temperature at the beginning of April and middle of October.Annual averagetemperatures of various surfaces increase as the pavement width increases but decrease as the wind speed and the roadbed height increase,especially for asphalt pavement and both-side road shoulder.Furthermore,the variation of route trends has great influence on annual average temperature of slope surface.The annual average temperatures of right and left slope surface along east west direction are the highest and lowest one respectively among all three route directions.

关 键 词：道路工程 宽幅路基 参数分析 耦合换热 地气耦合模型 

分 类 号：U416.1[交通运输工程—道路与铁道工程]