Unified modeling of setting and strength development

The effect of temperature on the development of concrete compressive strength can be modeled by the maturity approach once the temperature sensitivity of the mixture, quantified by the activation energy (Ea) of its chemical reactions, is known. It is common in maturity applications to use a unique value of Ea obtained for the hardening period, even though the effect of temperature is different on the rate of setting and hardening. Ea-values presented in the literature suggest that the temperature sensitivity is lower before hardening. This paper proposes a new approach to the traditional maturity method unifying the distinctly different temperature sensitivities before final setting and during hardening. Results of setting and compressive strength of mixtures with different cementitious materials were analyzed with activation energy values calculated for the periods before final setting and during hardening. For the investigated mixtures, the new approach led to improved strength predictions, suggesting that it is useful to take into account setting behavior in the development of the strength–maturity relationship.