Microporosity of Cellular Concrete and its Effect on Thermal Conductivity

A model of the porous structure of cellular concrete, which makes it possible to represent it in the form of macropores surrounded by a microporous cement stone (MCS) consisting of micropores and cement-silicate stone (CSS), is proposed. This model made it possible to establish in cellular concrete the dependence between the density coefficients, porosity, diameters of macro – and micropores and the distance between them, as well as to determine the dependence of the thermal conductivity coefficient of cellular concrete on the coefficients of its density, porosity of cement-silicate stone. It is shown that with a constant density of aerated concrete, its calculated coefficient of thermal conductivity decreases with a decrease in the density of MCS, due to the formation of micropores in it. Formulas are given, from which it follows that the distance between the pores is in direct proportional dependence on the size of the diameters of the macropores and the smaller their diameter, the smaller the distance between the pores and the lower the coefficient of thermal conductivity of cellular concrete.

V.P. VYLEGZHANIN¹, Candidate of Sciences (Engineering), Director (This email address is being protected from spambots. You need JavaScript enabled to view it.),
V.A. PINSKER¹, Candidate of Sciences (Engineering)
T.M. PETROVA², Doctor of Sciences (Engineering), Head of the Chair of Building Materials and Technologies

¹ Aerated Concrete Center (1/3, Zodchego Rossi Street, Saint-Petersburg, 191023, Russian Federation)
² Emperor Alexander I St. Petersburg State Transport University (9, Moskovsky Prospect, Saint Petersburg, 190031, Russian Federation)

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