Compatible Datum Temperature and Activation Energy for Concrete Maturity

Maturity methods are used to predict strength or other mechanical properties of a concrete mixture for a given moisture availability as a function of time and temperature. Temperature sensitivity of a mixture is characterized by datum temperature for the Nurse-Saul (NS) method, and by activation energy for the Freiesleben-Hansen and Pederson method (FHP). While these methods and their defining parameters were independently developed, the parameters are nevertheless interdependent, as a change in a concrete mixture that affects temperature sensitivity as expressed by datum temperature will also be reflected in a change of activation energy, and vice versa. This paper addresses the temperature- and mixturedependent relationship between datum temperature and activation energy, using both a closed-form equation based on chemical kinetics and experimental data where values of datum temperature and activation energy were found to provide the best fit to strength data. Best-fit results validate the closed-form solution.