Factors affecting early-age hydration of ordinary Portland cement studied by NMR: Fineness, water-to-cement ratio and curing temperature

The aim of the present study was to apply nuclear magnetic resonance (NMR) relaxation measurements for understanding the microstructure evolution of cement paste during hydration. Ordinary Portland cement powder was mixed with double-distilled water, and hydration process was analyzed via H-1 proton NMR spin-spin relaxation time. In order to induce strong modification of the rate of hydration, water-to-cement ratio, curing temperature and cement fineness were varied. The evolution of the NMR spin-spin relaxation time, T-2, of hydrating water versus the hydration time was monitored from the very first few minutes after the mixing up to several hours.