The paper presents the latest models for calculating the thermal conductivity of soil. Precise determination of this parameter is necessary for the correct and safe location of geoengineering objects, underground infrastructure such as cables or ground heat exchangers. A universal model that is easy to apply and gives the most accurate results has not yet been developed. New models are constantly being developed. The aim of this work is to present the latest models for calculating thermal conductivity, so that knowing the properties of the soil, it is possible to select an appropriate model to calculate its conductivity.

The paper presents mixed models collected from the literature for calculating the thermal conductivity of the soil. They are created on the basis of combining the serial and parallel model. The thermal conductivity of the soil is the basic thermal parameter of the soil. Knowledge of it is necessary, among other things, for the proper design of underground infrastructure. The combination of models will help you to choose the method of calculating the thermal conductivity of the soil that gives the most accurate results and has the lowest error.