Capillary water absorption of self-compacting concrete under different curing conditions

Abstract

This paper reports an experimental study carried out to investigate the influence of addition of pozzolanic materials and curing regimes on the mechanical properties and the capillary water absorption (sorptivity) characteristics of self-compacting concrete (SCC). Portland cement (PC) concrete and two types of SCC, SCC-I with fly ash (30% FA/70% PC) and SCC-II with silica fume (10% SF/90% PC), specimens were prepared and cured in three different curing conditions (standard 20°C water, sealed and air cured) for the periods of 3, 7, 14 and 28 days. At the end of each curing period, compressive and tensile strengths and ultrasonic pulse velocity (UPV) values were determined; sorptivity coefficents were determined at 28 days. The results indicated that SCC-II specimens gave higher compressive and tensile strength and lower sorptivity coefficient values than those of corresponding SCC-I and PC concrete specimens, regardless of curing regimes and age of concrete. The results also showed a good correlation between the strength development of concrete and its sorptivity, i.e., as the compressive and tensile strengths increased due to the hydration, the sorptivity coefficients decreased significantly.