Influence of Sucrose on Hydration Process of Portland Cement

摘要

The sucrose (0.045% of cement) is added in cement paste, the consistency of Ca~(2+) and OH~- reduce and the AFt is high solubility produced, thus the AFt exists as gel like product which covers the surface of the clinker particles, the sucrose acts as a retarder. When the dosage of the sucrose is 0.24%, the sucrose poisons the hydration of C_2S and C_3S markedly, so the consistency of Ca~(2+) and OH" reduce sharply and the AFt like needle form a hydration product network and accelerates the setting process, C_2S and C_3S cannot yield enough C-S-H, the strength development is baffled. It was supposed that there are two dosage threshold values of sucrose on the hydration process, 0.01% is a retardation threshold value accelerating the formation of AFt, while 0.2% is an acceleration threshold value poisoning the hydration of C_3S and C_2S.