Risk assessment of reactive local sand use in aggregate mixtures for structural concrete

Abstract

Potential use of marginal fine aggregate in concrete is hindered by prescriptive quality requirements for concrete constituents. Experimental tests were performed on eleven mixtures of coarse and fine aggregates of variable susceptibility to alkali silica reaction (ASR). The miniature concrete prism test was applied for evaluation of ASR-induced expansion and associated changes of elastic properties were evaluated using the resonance modulus testing. Substitution of nonreactive sand with sands of moderate reactivity resulted in a relative increase in concrete expansion by 19–112% and substantial reduction of its elastic properties during the exposure to accelerated ASR environment. The Kolmogorov-Avrami-Mehl-Johnson model, modified to incorporate separately the effects of moderate reactivity of coarse and fine aggregate fractions, successfully described the kinetics of ASR-induced expansion. Beneficial effects of blastfurnace slag used for partial replacement of Portland clinker in blended cements were captured for aggregate combinations.