The influence of ZnO nanoparticles on mechanical and early-age hydration behaviour of cement paste

ABSTRACT

An ultrasonic treatment was used to ensure that the nano zinc oxide abbreviated ZnO, was uniformly dispersed throughout the cement paste mixture with addition of fly ash, replacing 10% of the weight of cement. The characteristics of the cementitious mixture were investigated in this research work. The experimental work was carried out by adding nano-ZnO in increments of 0%, 0.25%, 0.5%, 0.75% and 1% by weight of cement, resulting in changes in the characteristics of the concrete paste. The quantity of nano-ZnO present in the cementitious mixture had a notable influence on the consistency of the cement. This impact was also found when the cement paste contained only 0.5% cement by weight. The electrical resistance studies found that the inclusion of nano-sized particles can both delay the hydration of blended cement mix and increase the hydration rate. The findings of experiments revealed that increasing the nano-ZnO concentrations in the cement paste resulted in greater long-term strength. Furthermore, the pore diameter distribution was optimized by the inclusion of nano-ZnO and a tight microstructure was formed in the cementitious mixture at 28 days.

Keywords:
Zinc Oxide; Nano-particles; Compressive strength; Tensile strength; Hydration