石灰石粉铝酸盐水泥复合体系的水化反应

石灰石粉具有水化活性，能与硅酸盐水泥中的C₃A、铝酸盐水泥中的CA、CA₂等铝酸盐矿物发生反应，水化产物为水化碳铝酸钙。利用微量热仪法、胶砂强度和X射线衍射（XRD），研究不同比例的石灰石粉铝酸盐水泥复合体系的水化反应，结果表明：石灰石粉会加快铝酸盐水泥的水化进程，水化过程诱导期缩短，放热速率峰值下降；复合体系中石灰石粉占比越高，早期水化反应速率越快，但水化反应放热量越低；相对而言，复合体系中石灰石粉掺量为20%时石灰石粉参与反应程度最高，且掺量为20%时石灰石粉对复合体系强度有显著贡献。随复合体系中石灰石粉比例增加，铝酸盐水泥水化产物越来越不明显；石灰石粉掺量为20%~40%时，水化碳铝酸钙XRD特征峰相对最明显，复合体系中石灰石粉与铝酸盐水泥存在一个最佳的比例范围。研究表明，石灰石粉与铝酸盐水泥间会发生明显的水化反应，石灰石粉与铝酸盐水泥复合有望制得一种新型胶凝材料。

Hydration of composite system with limestone powder and aluminate cement

imestone powder (LP) actually has hydration activity and can reacts with aluminate minerals, such as C₃A in Portland cement, and CA and CA₂ in aluminate cement (AC). The hydration product is calcium carboaluminate hydrate. In this paper, in order to study the hydration reaction, composite systems, which consist of limestone powder and aluminate cement, were analyzed by micro calorimeter, strength test and XRD. The results show that, LP could accelerate the hydration process of the system, and lead to a shorter induction period, an earlier and lower hydration heat peak in the hydration of aluminate cement. The more LP in the composite system, the faster the early hydration, but the lower the hydration heat of the composite system. 20% replacement of limestone powder is the most reactive and contributes significantly to the strength of the composite system. The more limestone powder in the composite system, the less hydration products of the aluminate cement. When the limestone powder content is 20%~40%, the XRD peak of calcium carboaluminate hydrate is relatively obvious. Accordingly, there is a optimal range of AC:LP in the composite system. It is concluded that a significant hydration reaction occurs between limestone powder and aluminate cement. The composite of limestone powder and aluminate cement is expected to produce a new type of cementitious material.