Equilibrium Sorption Humidity of Cellular Concretes and Its Polymolecular-Adsorbed and Capillary-Condensed Components

Equilibrium sorption humidity of building materials largely determines the progress of processes of heat- and moisture transfer through external enclosing structures of buildings and, consequently, the thermal resistance of these structures under the real conditions of operation. Therefore, when calculating the thermal resistance of structures, the information about the equilibrium sorption humidity of structures and its components at positive and negative temperatures is needed. The study of the sorption humidity process is conducted on the example of cellular concretes. The humidification of cellular concretes with vaporous moisture at temperatures from +35°C up to -10°C takes place mainly due to the phenomenon of polymolecular adsorption. The phenomenon of capillary condensation plays a prominent role in this process only at the values of relative air humidity close to 1 (100%).

I.Ya. KISELEV, Doctor of Sciences (ikiselyov@ bk.ru)

Research Institute of Building Physics of RAAСS (21, Lokomotivniy Driveway, Moscow, 127238, Russian Federation)

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