Thermal conductivity models of dispersed non-saline frozen soils

Background. The growing relevance of using numerical or analytical methods for solving engineering and geocryological problems in the permafrost zone is increasingly raising questions about determining input parameters. In the present-day practice, thermal properties of soils can be determined using numerical methods in addition to laboratory tests. The search for universal dependencies that most accurately describe the thermophysical properties of frozen soils is becoming an important task of modern research. This study considers models for assessing thermal conductivity of soils, taking into account the physical properties, mineral composition and water content of dispersed soils. These models have become widely used, primarily in foreign practice and contemporary software for thermophysical simulation.

Aim. To consider a method for using thermal conductivity models taking into account the physical properties, mineralogical composition and water content of frozen dispersed soils with the purpose of assessing their effectiveness.

Materials and methods. Two models for assessing the thermal conductivity of dispersed frozen soils are analyzed. A statistical analysis of their effectiveness is performed based on a sample of twenty experimentally determined thermal conductivity values of sandy and clayey non-saline, non-peaty frozen soils.

Results. The efficiency of using thermal conductivity models is at a satisfactory level. The expected values of thermal conductivity in a frozen state are predicted with greater accuracy compared to the method adopted in domestic practice. The most preferred methods considering the thermal conductivity of particles are determined.

Conclusion. A combination of physical properties, mineralogical composition, and unfrozen water content in the given models has clear advantages. A further study of this issue is necessary to expand the number of compared models and soil sample. The importance of considering the mineralogical composition in the assessment of thermal conductivity for dispersed frozen soils is demonstrated.

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