STUDY ON HYDRATION KINETICS OF C_3S IN NaNO_2 SOLUTION AT NEGATIVE TEMPERATURE

摘要

By measuring the concentration of Ca~(2+) in C_3S suspension at different negative temperatures, a regression for hydration kinetics at early stage is obtained, parameters from which (n=-1.28～-1.15, k=2.21～9.75) and apparent activation energy (E=10.69 KJ/mol) are also obtained. It is shown that the hydration reaction rate is influenced by temperature significantly, while the hydration reaction mechanism changes only a little, it is also found that there is a turning point at -10°C when C_3S hydrates at different negative temperatures. At present, it is recommended that the apparent activation energy of hydration reaction at early stage may be used to evaluate the efficiency of anti-freezing admixtures.