Influence of Porosity of Autoclaved Gas Concrete on Its Thermal Conductivity and Ways of Its Change Due To Improvement in Selection of Raw Components

A model of autoclaved gas concrete, which makes it possible to take into account the characteristic parameters of its porous structure (coefficients of density and porosity, pore diameters and distances between them), as well as the dependence of these parameters on the density coefficient of gas concrete, is proposed. The dependence of the thermal conductivity coefficient on the density of gas concrete only is justified. It is established that with the increase in the density of microporous cement stone, which is achieved due to the selection of the composition of raw components, the volume of microporous cement stone in the gas concrete decreases. It is shown that the increase or decrease in the diameter of the pores in the gas concrete, for example, due to selection of the grain size of the aluminum powder, at a constant porosity of gas concrete, its coefficient of thermal conductivity does not change. A method for determining the minimum pore diameter in the gas concrete based on the permissible distance between them, the determining parameter of which is the grain size obtained by grinding raw components, is proposed.

V.P. VYLEGZHANIN, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.)
V.A. PINSKER, Candidate of Sciences (Engineering)

Center of Cellular Concrete (1/3, office 308, Zodchego Rossi Street, Saint-Petersburg, 191023, Russian Federation)

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