南京地区砂土热物理性测试分析

Test and Analysis of Thermal Properties of Sand Soil in Nanjing

采用非稳态热探针对南京地区细砂进行热导率、热阻系数测试,研究含水量、干密度对细砂热导率的影响.研究结果表明:细砂热导率随含水量的增大而增大,即热阻系数随含水量的增大而减小,且当含水量增大至近饱和时热阻系数趋于常数;细砂干密度越大、粒径越大,热阻系数越小.本文探究地下水渗流对细砂传热的影响,渗流速度越大,细砂传热效率越高.

The thermal resistivity of fine sands in Nanjing district is tested by using transient probe, aimed at studying the effect of moisture content and dry density on thermal resistivity of fine sands. The results indicate that thermal resistivity increases when moisture content goes up. That is, thermal resistivity decreases as moisture content increases, and inclines to reach a constant when the water content of fine sands is close to saturation; the higher the fine sands＇ dry density is, and the larger the fine sands＇ diameter is, the smaller the thermal resistivity is. The impact of groundwater seepage on the heat transfer of soil is also studied, which indicates that the faster the groundwater seeps, the more efficiently the find sands transfer heat.