岩土体导热系数在与地热有关的地质基础研究和生产应用中有重要作用.首先介绍了导热系数的概念,然后分析了导热系数的受控因素,最后探讨了导热系数的测定方法.导热系数的受控因素包括地层岩性、孔隙率、含水率、温度以及各向异性.导热系数随地层岩性从大到小排列为海相碳酸盐岩、陆相碎屑岩、火成岩,变质岩导热系数与母岩和变质程度有关；同种岩层的导热系数随沉积过程延续或深度增加而增大；含水率对软弱岩石的导热系数影响较大,导热系数随含水率增大而增大,对孔隙度较大的岩层需进行饱水校正；不同岩性的导热系数随温度的变化较复杂,在应用中需结合实际地层考虑；由于结构面的存在,岩体的导热系数存在各向异性.导热系数的测定方法包括现场测试法、室内测试法、组分类型辨别法以及利用P波速度估算等.利用现场数据求解导热系数时常使用线热源模型和柱热源模型；室内测试法包括稳态测试法和非稳态测试法,分别应用于中低导热系数材料和高导热系数材料；对于组分类型辨别法,平行板式相分布的物体导热系数是各向不等的,热传导方向与平行板平面平行和垂直时分别具有最小和最大总体导热系数；对地下无法直接测量的地质单元,可利用P波速度估算导热系数.要得到准确的导热系数,须基于岩土体的导热系数范围和样品特征选取正确的测定方法.%Thermal conductivity coefficient of rock and soil mass is important on the geothermic fundamental research and application. Concept, controlled factors and measuring methods of thermal conductivity coefficient were introduced. Controlled factors included stratum lithology, porosity, water content, temperature and anisotropy. Thermal conductivity coefficient ranked by descending order with stratum lithology was marine carbonate, continental clastic rock and igneous rock, and thermal conductivity coefficient of metamorphic rock was related with the parent rock and metamorphoses degree. Thermal conductivity coefficient increased when the sedimentation and depth increased. Water content had significant influence on thermal conductivity coefficient of weak rocks thermal conductivity coefficient increased with the increase of porosity; the stratum with big porosity should be checked with saturation. Thermal conductivity coefficient of different lithology was complex when the temperature changed, so it should be concluded according to the actual stratum in application. Thermal conductivity coefficient was anisotropic because of the structural plane. Measuring methods of thermal conductivity coefficient included field test, indoor test, component types distinguishing, P-wave velocity estimation, etc. Thermal conductivity coefficient with field test data was usually calculated by linear and columnar source models. Indoor test included steady and unsteady measuring methods, which were applied in the materials with low-middle and high thermal conductivity coefficient respectively. For component types distinguishing method, thermal conductivity coefficient of the parallel plate phase distribution material was anisotropic; thermal conductivity coefficient was minimum when the direction of heat exchange was parallel to parallel plate and maximum when the direction was vertical to parallel plate.For the geological unit which can not be directly measured, P-wave velocity estimation was used to calculate thermalconductivity coefficient. In order to obtain accurate thermal conductivity coefficient, optimal measuring methodshould be selected based on the characteristics of samples and the extent of thermal conductivity coefficient of rockand soil mass.
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