Measurement of thermal conductivity for frozen soil at temperatures close to 0 °C

A Fourier's law-based approach that can be used for measuring multiple thermal conductivities in one specimen simultaneously at temperatures close to 0 degrees C is described. The temperature gradient between neighboring points was observed, and the heat flux was the product of thermal conductivity from transient-state method and temperature gradient near specimen end with a temperature much lower than 0 degrees C. Distinguished from the thermal conductivity of frozen soil samples with low temperatures, the measured thermal conductivity of frozen soil samples at temperatures near 0 degrees C increased as temperature decreased, and the average increasing-rate of thermal conductivity was greater than 0.1W/(m . K)/degrees C. The developed approach validated by the independent estimations from the empirical model in literatures, and is expected to be an effective technique for measuring thermal conductivity for frozen soils with a wide range of temperatures. (C) 2019 Elsevier Ltd. All rights reserved.