Effect of Triethanolamine on Hydration Kinetics of Cement-Fly Ash System at Elevated Curing Temperature

As a high-output industrial byproduct, fly ash can partially replace Portland cement in concrete, which is one of the important treatment methods to improve its utilization. However, the low activity of fly ash limits its substitution level. Previous studies demonstrated that adding triethanolamine (TEA) and elevated curing temperature are useful methods to promote the pozzolanic activity of fly ash, while the effect of TEA on the hydration kinetics of the cement-fly ash system (CFA) under elevated curing temperature is unclear. In this study, the hydration kinetics of the CFA system with different dosages of TEA under elevated curing temperature were investigated. The activation energy and pore solution of samples were analyzed to further clarify the corresponding mechanism. The results show that the effect of TEA on the hydration kinetics of the CFA pastes at 60 degrees C is different from that at 20 degrees C. The mean activation energies for each hydration process (NG, I, and D) of CFA pastes all decrease with the increased TEA dosage. The effect of TEA on the hydration kinetics of the CFA pastes at elevated temperature is closely related to the dissolution of the CFA system. These findings will further promote the high-value-added utilization of fly ash.