高寒地区沥青路面铺筑短期影响冻土温度场的数值分析  

Numerical Analysis of Short-term Affecting Frozen Soil Temperature Field During Asphalt Pavement Filling in High-cold Regions

作　　者：陆永东 杨博 张文凯[1] 吴忧 LU Yongdong;YANG Bo;ZHANG Wenkai;WU You(School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China;National&Local Joint Engineering Research Center of Transportation and Civil Engineering Materials,Chongqing Jiaotong University,Chongqing 400074,China)

机构地区：[1]重庆交通大学土木工程学院,重庆400074 [2]重庆交通大学交通土建工程材料国家联合地方工程研究中心,重庆400074

出　　处：《公路工程》2024年第6期87-92,133,共7页Highway Engineering

基　　金：重庆市自然科学基金项目(CSTB2023NSCQ-MSX1024);重庆交通大学自然科学类揭榜挂帅项目(XJ2023000201);重庆市研究生教育项目(YKCSZ23123);重庆交通大学研究生教育项目(KCSZ2022001)。

摘　　要：为了探索高寒地区沥青路面铺筑短期对冻土层温度场的影响,通过对路面各结构层材料进行热传导试验和碎石空隙率试验,得出不同结构层的热力学参数,通过有限元方法建立二维冻土温度场模型,分析了沥青路面在4月、7月和10月份铺筑短期对冻土温度场的影响规律。结果显示:沥青路面铺筑短期的热效应使得冻土温度场呈梯形分布。其中,7月份铺筑路面造成冻土层温度上升最高可达2.13℃,冻土0℃等温线下降深度大于0.78 m,最不利于冻土的温度稳定性。为此,基于弯沉等效思想在路基顶面通过铺设碎石层进行温度改善和刚度补偿设计,结果显示:铺设1.0 m厚的碎石层,路基和冻土层温度下降1.89~27.22℃,0℃等温线抬升0.54~1.95 m,路基顶面当量回弹模量可提升至125~180 MPa,以上可为高寒冻土地区的公路建设提供参考。In order to explore the impact of short-term asphalt pavement construction on the temperature field of permafrost in high-cold regions,thermal conductivity tests and gravel porosity tests were conducted on the materials of each structural layer of the pavement to obtain the thermodynamic parameters of different structural layers.A two-dimensional frozen soil temperature field model was established using finite element method,and the influence of short-term asphalt pavement construction on the frozen soil temperature field in April,July,and October was analyzed.The results show that the thermal effect of short-term asphalt pavement construction results in a trapezoidal distribution of frozen soil temperature field.Among them,the pavement construction in July caused a maximum temperature increase of 2.13℃in the permafrost layer,and the depth of the 0℃isotherm decrease of permafrost was greater than 0.78 m,which was the most unfavorable for the temperature stability of permafrost.Therefore,based on the concept of equivalent deflection,temperature improvement and stiffness compensation design are carried out on the top surface of the roadbed by laying a crushed stone layer.The results show that laying a 1.0 m thick gravel layer reduces the temperature of the roadbed and permafrost layer by 1.89~27.22℃,and the 0°C isotherm rises by 0.54~1.95 m.The equivalent elastic modulus of the roadbed top surface can be increased to 125~180 MPa,which can provide reference for highway construction in high-cold permafrost areas.

关 键 词：公路冻土路基 沥青路面 温度场 0℃等温线 碎石路基 

分 类 号：U414[交通运输工程—道路与铁道工程]