The effect of alkali reactivity on the mechanical properties of concrete

The effects of highly reactive aggregate, fused silica, and slowly reactive aggregate, Thames Valley sand, on the mechanical properties of concrete were investigated in this paper. The mechanical properties studied over a period of 12 months were the compressive strength, direct tensile strength, tensile splitting strength, flexural tensile strength (modulus of rupture), static modulus of elasticity and water absorption. The effects of both reactive aggregates on the mechanical properties of concrete were compared with that of sound concrete mix. The results presented in this investigation show that the effect of the reactive aggregates on the mechanical properties varies, depending on the type of reactive aggregate. From this study it appears that the direct tensile and static modulus of elasticity were the best indicators of reactivity. (C) 2002 Elsevier Science Ltd. All rights reserved.