Using Isothermal Calorimetry to Predict Setting Time of Cement-Based Materials (CBMs)

Abstract

AbstractIn this study, the rate of heat evolution curve obtained from isothermal calorimetry is used for predicting the setting time. A derivative curve plot from the rate of heat evolution was used to determine the initial setting time (IST) and final setting time (FST) of cement paste and mortar containing different w/c ratio. Also, conventional methods such as IS 4031(part-5) and ASTM C403 were taken to determine the setting times. The correlation was developed between setting time obtained from the derivative plot and IS 4031 for cement paste sample, and derivative plot and ASTM C403 for mortar samples. The study indicates that the isothermal calorimetry techniques can be used to determine the setting time with ± 0.37–4.48 h deviation for cement paste and ± 0.43–3.78 h for the mortar, regardless of IST and FST. Further, a very high coefficient of correlation with 0.95 for IST and 0.99 for FST was obtained. Besides, longer setting times were obtained from the calorimetry method as to IS and ASTM setting time method.KeywordsIsothermal calorimetrySetting timeRate of heat evolutionDerivative curveCoefficient of correlation