Impact of additional water on cementitious materials containing superabsorbent polymers: effects on compressive strength and autogenous shrinkage

There are divergent views in the literature regarding the use of additional water in cementitious materials containing superabsorbent polymers (SAP). The polymer is mainly used to mitigate autogenous shrinkage. Some studies report a decrease in compressive strength and attribute it to the addition of SAP, while others argue that the real issue is the use additional water. The aim of this study is to analyze the state of the art regarding the influence of additional water in cementitious mixtures containing SAP and its effect on compressive strength and autogenous shrinkage. Microconcretes and pastes are categorized based on SAP dosages and systematic reviews of the relevant literature. The methodology employs a parameterization approach for standardized comparisons, considering water-to-cement ratios (w/c) and total water content. Autogenous shrinkage and compressive strength are analyzed for each mixture, with and without extra water. Results reveal distinct behaviors, indicating optimal SAP dosages of 0.20% by weight of binder for balancing autogenous shrinkage mitigation and minimal harm to compressive strength. In conclusion, this research contributes valuable insights into SAP’s effectiveness in mitigating autogenous shrinkage and provides a foundation for optimising SAP dosages in different cementitious materials. The findings facilitate informed decisions for durable concrete construction practices.