摘要
通过测定磷酸及磷酸盐类化合物对水泥浆体水化热、Zeta电位和液相中离子浓度的影响,研究它们对水泥水化动力学的影响。结果表明:磷酸和磷酸盐类化合物明显延长了水泥水化诱导期,并降低了水泥水化加速期水化速率。与磷酸或单磷酸盐相比,聚磷酸盐类化合物更多地延长了水化诱导期时间;磷酸比磷酸盐类化合物更为显著地降低了水化最大放热速率;磷酸和磷酸盐类化合物均可降低水泥早期的溶解速率,同时改变了水泥颗粒表面的性质;磷酸和磷酸盐类化合物对水泥水化动力学的影响,与其在水泥表面形成包覆层影响了水泥溶解速率及成核速率有关。
The impacts of phosphoric acid and phosphates on the hydration kinetics of Portland cement were investigated via moni- toring isothermal heat evolution of cement hydration, the measurement of Zeta potential and the elemental concentrations in the aqueous phase of the hydrating cement pastes. The results indicate that phosphoric acid and phosphates can prolong the induction period of cement hydration, and decrease the hydration rate during the acceleration period. The impacts of phosphoric acid and phos- phates on the hydration kinetics of portland cement could be due to the formation of the precipitates coveting the surface of the hy- drating cement grains, which reduced the dissolution rate of cement phases and affected the nucleation process of hydrates. The Zeta potential measurement and aqueous ion concentration tests of cement pastes exhibited the formation of the precipitate covered on cement surface.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2012年第11期1553-1558,共6页
Journal of The Chinese Ceramic Society
基金
国家自然科学基金(51173094)资助项目
关键词
磷酸
磷酸盐
水泥水化
水化热
缓凝
诱导期
溶解速率
phosphoric acid
phosphates
cement hydration
hydration heat
retardation
induction period
dissolution rate
