Nano CaCO3 for enhancing properties of cement-based materials: a comprehensive review

Nanomaterials have emerged as a future application to concrete technology due to their unique composition. This study presents a review of nano CaCO3 in terms of microstructure, rate of hydration, consistency, flowability, setting time, workability, compressive strength, sorptivity, chloride resistance, and corrosion resistance. A remarkable decrease in pores and chloride ion penetration can be observed from the study. Compared to the controlled concrete, the addition of 1% nano CaCO3 also resulted in the reduction of the chloride diffusion coefficient. Compressive strength showed a significant improvement with the inclusion of 1-2% nano CaCO3, however, increasing its quantity showed reduction in compressive strength property. The accelerated hydration reaction forming supplementary C-S-H gel observed in the concrete containing nano CaCO3 has remarkably improved the microstructure of the mix by reducing its porosity. This study is an initiative to accumulate findings of nano-materials for its broad acceptance and future scope of work.