MONITORING PORTLAND-CEMENT HYDRATION - COMPARISON OF METHODS

Various experimental methods of monitoring Portland cement hydration are compared. The methods are quantitative X-ray diffraction analysis (QXRD), measurement of non-evaporable water as loss on ignition and by thermogravimetry, conduction calorimetry and measurement of chemical shrinkage. Correlations between these different measures of hydration are obtained using samples of paste for three different Portland cements. The correlation between non-evaporable water and QXRD data was dependent on the chemical composition of the cement and shows that less water was chemically bound at early ages, for a given amount of cement reacted. A near-linear relationship was found between chemical shrinkage and QXRD data. The correlation between heat of hydration and QXRD data was approximately linear and not greatly affected by cement type. © 1990.