Mitigation of Restrained Plastic Shrinkage Cracks in Concrete: A Systematic Review on the Role of Chemical Admixtures

Plastic shrinkage cracks are a major concern in concrete structures, arising from rapid moisture loss before the development of adequate tensile strength. These cracks compromise durability, increase permeability, and accelerate structural deterioration. Effective mitigation strategies are therefore essential to improve concrete performance and serviceability. This study examined the mechanisms and performance of various admixtures, including shrinkage‐reducing admixtures (SRAs), superplasticizers (SPs), accelerators (ACCs), and retarders (RETs), to mitigate plastic shrinkage cracks. The preferred reporting items for systematic reviews and meta‐analyses (PRISMA) framework was utilized to select peer‐reviewed articles from Web of Science (WOS), ensuring a comprehensive evaluation of their mechanisms and effectiveness. The findings indicate that SRAs reduce surface tension, lowering capillary pressure and evaporation rates. ACCs accelerate hydration, minimizing the period of vulnerability to shrinkage, while RETs delay setting, allowing longer moisture retention. SPs improve workability, reducing settlement‐induced cracking. One‐way analysis of variance (ANOVA) indicated statistical significance ( p < 0.05) for the variation in crack reduction ratio (CRR) among admixture groups. The box plot and Tukey HSD analysis indicated that SRAs exhibited superior performance, followed by SPs, RETs, and ACCs. Pearson’s and Spearman’s correlation coefficients, together with regression analysis, indicated that SRAs exhibited superior performance in humid and windy conditions, but inferior performance at elevated temperatures. SPs showed superior performance in humid and elevated temperature conditions but diminished efficacy in windy situations. ACCs perform adequately in elevated temperatures but are less effective in windy conditions. RETs demonstrated optimal performance in humid conditions and a fair performance at elevated temperatures but demonstrated worse efficacy in windy situations.