青藏工程走廊带多年冻土导热系数测试方法对比研究  

Comparative study on measurement methods of permafrost thermal conductivity of Qinghai-Tibet engineering corridor

作　　者：崔福庆[1,2] 刘志云[1] 陈建兵[2] 彭惠[2] 张伟[1] 王伟 CUI Fu-qing;LIU Zhi-yun;CHEN Jian-bing;PENG Hui;ZHANG Wei;WANG Wei(College of Geology Engineering and Geomatics,Chang’an University,Xi’an 710054,China;State Key Laboratory of Road Engineering Safety and Health in Cold and High-Altitude Regions,CCCC First Highway Consultants Co. ,Ltd. ,Xi’an 710065,China)

机构地区：[1]长安大学地质工程与测绘学院,陕西西安710054 [2]中交第一公路勘察设计研究院有限公司,高寒高海拔地区道路工程安全与健康国家重点实验室,陕西西安710075

出　　处：《西安科技大学学报》2020年第5期887-893,共7页Journal of Xi’an University of Science and Technology

基　　金：国家自然科学基金项目(51574037,41502292);中国交通建设股份有限公司应用基础研究项目(2018-ZJKJ-PTJS03)。

摘　　要：为分析不同测试方法对青藏工程走廊带内多年冻土导热系数测试结果的影响规律,指导冻土工程的热工设计和为走廊带内冻土导热系数的测试方法选择提供依据,搭建了稳态对比法、稳态热流计法、瞬态平面热源法和瞬态热线法冻(融)土导热系数试验测试平台,运用理论模型对稳态对比法测试过程中径向漏热量进行了估算,分别从测试结果准确性、适用土性类别和适用场合等方面对各类测试方法进行了对比。结果表明:稳态对比法试验结果与文献理论值相差较大,测试过程中径向漏热量无法忽略;稳态热流计法和瞬态平面热源法的测试结果与理论计算值具有较好的一致性,80%以上的测量值与理论值相对误差小于±15%;瞬态热线法测试结果整体偏小,冻、融土平均偏小17.75%和15.03%.考虑到瞬态平面热源法测试结果准确,测试时间短,样品需求量小,因而是一种合适的青藏工程走廊带冻(融)土导热系数大规模测试方法。To compare the influence of measurement methods on the test results of permafrost thermal conductivity in the Qinghai-Tibet engineering corridor,guide the thermal design of cold region engineering and provide reference for the selection of testing methods of permafrost thermal conductivity,the steady-state comparison method(standard method),steady-state heat flow meter method,transient plane source(TPS)method and transient hot wire(THW)method have been established to measure the thermal conductivity of frozen/thawed specimens in present work.A theoretical model was developed to calculate the radial heat leakage of the steady-state comparison test.Different measurement methods were analyzed and compared in terms of test results accuracy,applicable soil properties,and applicable situations.The research results show that:test results of steady-state comparison method are quite lower than those of the theoretical values reported in literature and its actual radial heat leakage cannot be ignored;test results of steady-state heat flow meter method and TPS method have good consistency with the empirical formula calculation values,and the relative deviation of more than 80%of the measured results are less than 15%compared to the theoretical values;the overall results of the THW method are quite small:the average relative deviation of the unfrozen soil is 15.03%,and the frozen soil is 17.75%.Therefore,with test accuracy higher,test time shorter and samples smaller,the TPS method is a suitable large-scale test method for the permafrost thermal conductivity measurement in the Qinghai-Tibet engineering corridor.

关 键 词：多年冻土 导热系数 稳态热流法 瞬态平面热源法 瞬态热线法 

分 类 号：P642[天文地球—工程地质学]