Abstract Usually, for basic investigations on the hydration behaviour of CA (monocalcium aluminate, CaAl2O4) preferably pure samples without the presence of other hydraulic phases are used. In the presented study we apply an alternative approach investigating mixes that contain tiny to low amounts of CA (0.5–20 wt%) besides CA2 (CaAl4O7) or C6AF2 (Ca6Al2Fe4O15). The hydration of the mixes is investigated by isothermal heat flow calorimetry, in-situ XRD and pore solution analysis at 23 °C. A modified thermodynamic database enables the calculation of saturation indices for relevant hydrate phases in the investigated systems. CA similarly influences the hydration of both CA2 and C6AF2 although the exact impact strongly depends on the initial CA/water ratio in the mixes. Up to a certain amount CA is completely consumed during the first minutes after mixing. Beyond this amount the presence of undissolved CA causes an induction period and retards the hydration of CA2 or C6AF2.

中文翻译：

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CA初始溶解对CAC水化机制的影响

摘要 通常，对于 CA（铝酸一钙，CaAl2O4）水化行为的基本研究，最好使用不存在其他水硬相的纯样品。在目前的研究中，我们应用了一种替代方法来研究除了 CA2 (CaAl4O7) 或 C6AF2 (Ca6Al2Fe4O15) 之外还含有少量到少量 CA (0.5-20 wt%) 的混合物。通过等温热流量热法、原位 XRD 和孔隙溶液分析在 23 °C 下研究了混合物的水合作用。修改后的热力学数据库能够计算所研究系统中相关水合物相的饱和度指数。CA 类似地影响 CA2 和 C6AF2 的水合作用，尽管确切的影响在很大程度上取决于混合物中的初始 CA/水比例。在混合后的最初几分钟内，多达一定量的 CA 被完全消耗。超过这个量，未溶解的 CA 的存在会导致诱导期并延迟 CA2 或 C6AF2 的水合作用。