Synergistic effect of EVA, TEA and C-S-Hs-PCE on the hydration process and mechanical properties of Portland cement paste at early age

This work investigates the synergistic utilization of EVA, TEA and C-S-Hs-PCE as admixtures in Portland cement. The alteration of hydration process is measured by isothermal calorimetry (ICC) and the effects of admixtures on mechanical properties are evaluated by the development of strengths and apparent density. The mechanism of admixtures acting in cement is revealed via XRD, FT-IR and TGA techniques. Results show that the fluidity of fresh cement paste is significantly improved with the addition of EVA, TEA and C-S-Hs-PCE, and consequently to the increasing in workability. The admixtures accelerate the hydration process and increase the cumulative heat release, deepening the hydration degree of cement paste. Both the improvement of fluidity and promotion of hydration are the important reasons for the enhancement of mechanical properties. Results of XRD, FT-IR and TGA indicate that the CH contents increase evidently with the content of admixtures, which further proves that the deepening of hydration process. This study could provide an experimental reference, which is of great significance to the valuable application of admixtures in cement based materials.