Performance of two types of concrete containing waste silica sources under MgSO4 attack evaluated by durability index

Abstract

In this study, microsilica (MS) and glass powder (GP; waste of glass bead production industries) were used in the two widely used concretes, Ordinary Concrete (OC) and Self-Consolidating Concrete (SCC), as supplementary waste materials to evaluate the performance of those concretes under severe magnesium sulfate attack. Concrete samples with different range of MS and GP substitution were kept in the severe magnesium sulfate solution for up to 150 days. Fresh and hardened concrete properties were measured before exposure to the Magnesium sulfate. Mass change, volume change, and compressive strength loss of the samples were measured at different intervals after exposure. Mass change results showed that self-consolidating concretes generally perform better than normal concretes up to 88% because of the contribution of superplasticizer. Regarding the mass stability, supplementary materials had a considerable positive impact on the durability of OC under magnesium sulfate attack but did not improve the self-consolidating concretes durability performance, noticeably. A durability index was devised to take into account the measured parameters simultaneously and rank each mixture with less human judgment. The durability index confirmed that six percent GP and MS substitution in SCC mixtures show the best deterioration resistance between all of the mixtures.