Early strength development and hydration of cement pastes at different temperatures or with superplasticiser characterised by electrical resistivity

Abstract

The effects of the curing temperature and superplasticiser on the hydration rate and early strength development of cement pastes were investigated using their electrical resistivities. The cement pastes were prepared either at various temperatures or with different dosages of the superplasticiser. A general equation for electrical resistivity development was employed to monitor the paste rate of densification during the hardening period. The cement pastes obtained at a high temperature or optimal dosage of the superplasticiser had a faster densification than those of the pastes obtained at a low temperature or excessive dosage of the superplasticiser because of their higher rates of hydration. The electrical resistivity can be used to evaluate the factors that influence the hydration rate, microstructure, and early physical properties of the cement paste as well as for a better utilisation of admixtures and determination of the optimal dosage for hydration and paste structure formation.

Keywords

• Cement hydration
• Electrical resistivity
• Superplasticiser
• Curing temperature
• Densification rate