Łukasz Majewski, Jacek Kubissa, Wojciech Kubissa and Roman Jaskulski
The paper present the results of research on influence of environmental actions on sorptivity of concrete as a measure of its durability. Four series of concrete with different composition were tested. CEM III/A 42.5N cement was used in the amount of 400 kg/m3 (w/c = 0.4) and CEM II/BV 32.5N cement in the amount of 300, 250 and 200 kg/m3 (w/c = 0.5, 0.6 and 0.75 respectively). River sand and natural gravel were used as aggregate. After 28 days of storage in two different conditions (cured in water and not cured), they were subjected to accelerated carbonation and freeze-thaw cycles. The specimens were then dried to constant weight at 105°C and they were tested for sorptivity. Concrete carbonation decreased the sorption of not cured specimens and had little effect on the results of specimens cured in water. A significant influence of cyclic freezing and thawing of specimens on sorptivity was found, especially in the case of concretes with higher w/c not cured in water. In the case of concrete with CEM III cement, the increase in sorptivity after 25 F-T cycles was over 100%.
Concrete sorptivity, carbonation, compressive strength, coupled environmental actions.