The effect of curing temperature on white cement hydration

Cement manufacture has undergone extensive change in its attempts to rise to the successive challenges posed by society. The hydration of Portland cement is a complex phenomenon that depends on both reagent characteristics and reaction conditions. It is a well-known fact that the curing temperature plays an important role on the hydration kinetics. The present study is the first to be undertaken on the effect of curing temperature on white Portland cement paste hydration over long hydration times (365 days at 20 degrees C and 724 days at 60 degrees C). The technique used, Si-29 and Al-27 NMR spectroscopy, is particularly well adapted to the study of cement hydration. White cement hydration generates a C-S-H gel in which the aluminium taken up forms bridge bonds. After nine days at 60 degrees C. the degree of reaction expressed in terms of the AI(IV)/AI(VI) ratio nearly doubles the value found after 90 days at 20 degrees C. (C) 2008 Elsevier Ltd. All rights reserved.