### STRUCTURAL AND MATHEMATICAL MODEL OF THE THERMAL CONDUCTIVITY OF CONCRETE

#### Abstract

**Introduction:**The significance of energy saving in residential construction is associated with the reliable determination of design thermal conductivity characteristics of construction materials. The authors describe a concept of the structural and mathematical modeling of concrete thermal conductivity. The concept is based on methods of the structural approach and generalized conductivity theory.

**Purpose of the study:**The study is aimed at developing an adequate structural and mathematical model to determine the thermal conductivity of concrete.

**Methods:**The authors used the statistical method as a representation of the statistical homogeneity of a multi-component composite closely related to thermal homogeneity, which is understood as a medium with effective thermal resistance constant in space.

**Results:**The authors developed a structural and mathematical model to determine the thermal conductivity of concrete. The model accounts for concrete structural factors existing at the time when the structure formation of concrete is, for the most part, complete. The model also accounts for the thermal and physical properties of concrete components as well as macro- and mesostructural features of concrete. The paper presents calculated data for potential macro- and mesostructural factors, which makes it possible to determine the thermal conductivity of concrete characterized by low thermal conductivity and use the results derived for the approximation of prediction trends related to the thermal properties of such concretes in the operation and adaptation period during the use of building envelopes.

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PDF#### References

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DOI: https://doi.org/10.23968/2500-0055-2020-5-1-20-29

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