多年冻土地区热棒路基温度场的研究.pdf

摘要热棒路基是保护多年冻土地区路基冻土上限不下降的特殊工程措施之一,本文采用室内热棒试验、现场路况调查、现场测试与数值模拟对热棒路基的降温效果及路基温度场展开研究,取得一系列的研究成果: (1)进行室内热棒试验,分析了不同温差下热棒的工作效率,确定了热棒的启动温差和换热效率。试验表明,室内的降温效果下,该热棒启动温差为5℃,换热效率 。(2)对多年冻土地区热棒路基病害进行调查,采用手动动力触探对热棒路基的路肩及边坡进行承载能力测试,从水、热的角度分析了病害发生的原因。(3)对青藏公路五道梁试验路段的测试数据进行整理,分析了热棒路基工作周期及最大融化深度等温度变化特征。试验路数据表明,热棒路基的降温效果比较明显,有利于保护路基下的多年冻土层。(4)基于温度场控制方程,建立了热棒路基温度场模型,结合试验路的边界条件, 对试验路的热棒路基进行了数值模拟,验证了模型的正确性;并对未来10年的热棒路基温度场进行数值模拟,分析了热棒路基内部温度变化特性。(5)基于数值模拟结果及冻土地区路基设计原则,提出了热棒路基的设计原则。关键词:多年冻土地区热棒路基试验测试温度场设计原则 Abstract Thermal probe subgrade is one ofthe special project measures to protect subgrade permafrost cap don’tfallinperma劬st articlebases on the indoor thermal probe test,on-site road condition investigation,field testing andthenumerical simulation to research thecooling effectofthermalprobesubgrade and itstemperature aseries ofresearch results: (1)Takes indoorthermal probe test,analyses thework efficiency ofthethermal probe indifferenttemperature range,determines thestartingtemperature difference and heat transmission testshows that thestartingtemperature ofthermal probe is 5"C,the heattransmissioneffectiveness . (2)Investigates the diseases ofthermal probe subgrade inpermafrost region,using manual power touch agent to tests carrying capacity ofshoulder and slope,analyzes the disease causes fromwaterandheatangle. (3)Through finishing thetestdataof test section on WuDaoliang areaofthe qinghai-tibetplateau,analyzes thework period and themaximum thawing depth variation characteristics ofthethermal probe testdatashows that thecooling ef-fectof thethermal probe subgrade isgood toprotect thepermafrost layer under the subgrade. (4)According tothegoverning equation oftemperature field,this articlebuildsthe temperature fieldmodel ofthermal probe bined with theboundary conditions of testing road,article simulates thethermal probe subgrade numerically,proves the correctness ofthesimulation,simulates the