Investigating the effect of hybrid curing on mechanical and durability properties of normal-strength concrete

Internal curing is commonly implemented in concrete mixes with water-to-cement (w/c) ratios lower than 0.4 because of self-desiccation. Normal Strength Concrete (NSC) with w/c ratios higher than 0.5 would benefit from internal curing because of labor and resource-saving and quality control issues. However, the loss of curing water due to evaporation reduces internal curing efficiency in high w/c ratio mixes. This research evaluates a novel approach to minimizing internal curing water loss at an early age by combining internal curing with permeability-reducing admixtures (PRA) and shrinkage-reducing admixtures (SRA). Different mixtures containing binary and ternary combinations of admixtures and internal curing agents were investigated. According to the findings, admixtures such as SRA and PRA can play a vital role in maximizing the potential of internal curing in high w/c mixes. Furthermore, the ternary combination of LWA and the two admixtures has proven promising based on the observed overall improvement in NSC properties.