Streszczenie:

The paper presents an analysis of the influence of the moisture content in autoclaved aerated concretes on their drying. The tested material consisted of 60 cubic samples (10 x 10cm) of fly ash aerated concrete and sand aerated concrete, types 400 and 600. The analyzed physical parameters of the samples, such as specific density, bulk density, porosity, tightness and absorbtivity, were presented in the paper. The tests revealed that the rate of autoclaved aerated concrete drying depends in the first place on its structure and the moisture content. The drying period of samples soaked with water was the shortest for the sand aerated concrete type 600. The longest drying period was observed for the samples of the fly ash aerated concrete type 600. The results of conducted analyses allowed for distinguishing two phases of autoclaved aerated concrete drying: the first - up to 10 days, when an intensive decrease in mass wetness takes place, and the second - from 10 to 25-40 days, when a slow decline in mass wetness is observed.