粉性土导热系数的室内实验研究

Laboratory experiment on thermal conductivity of silty clay

介绍了一种在一维稳态导热状态下测量土壤导热系数的新方法——稳态平板法.该方法试样制备简便、干扰因素少、测试数据可信、成本低廉,便于工程测试应用.利用该方法测定2种典型土壤在不同干密度、水的质量分数条件下的导热系数.实验结果表明,土壤的导热系数随着水的质量分数和干密度的增加均有不同程度的提高;采用新方法得到的导热系数变化规律与采用探针法测量的结果较为一致.根据实验数据拟合得出土壤导热系数与土中水质量分数、干密度的经验公式,可供工程设计参考.

A new estimation method of soil thermal conductivity,slab method,was presented,which measures the soil thermal conductivity in one-dimensional steady heat conduction process.Compared with the conventional methods,the new method has many advantages,such as convenient specimen preparation,less interference factors,higher measuring accuracy and lower cost.Using this method,the thermal conductivities of two typical soils with different water ratio and dry density were tested.The soil thermal conductivity increases with the increasing dry density and water ratio.The variation curves of the soil thermal conductivity obtained in the experiment is well consistent with those of the thermal probe method.An empirical equation of the soil thermal conductivity and water ratio was derived by curve fitting based on the experimental results,and it is convenient for engineering application.