Antunes Mónica, Santos Rodrigo Lino, Pereira João, Horta Ricardo Bayão, Paradiso Patrizia, Colaço Rogério
Faculty Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
CIMPOR-Cimentos de Portugal, SGPS S.A., Praceta Teófilo Araújo Rato, 2600-540 Alhandra, Portugal.
Materials (Basel). 2021 Sep 16;14(18):5347. doi: 10.3390/ma14185347.
In this work, the apparent activation energy () of a novel low-calcium binder was, for the first time, experimentally determined, using a calorimetric approach. Additionally, a correlation between the , measured at the acceleration period with the C/S ratio of the hydration product is proposed. The of the prepared pastes was determined through isothermal calorimetry tests by calculating the specific rate of reaction at different temperatures, using two different approaches. When comparing the , at the acceleration period of this novel binder with the one published for alite and belite, we observed that its value is higher, which may be a result of a different hydration product formed with a distinct C/S ratio. Finally, to study the temperature effect on the compressive strength at early ages, a set of experiments with mortars was performed. The results showed that the longer the curing time at 35 °C, the higher the compressive strength after 2 days of hydration, which suggests a higher initial development of hydration products. This study also indicated that the novel binder has a higher sensitivity to temperature when compared with ordinary Portland cement (OPC).
在这项工作中，首次采用量热法通过实验测定了一种新型低钙粘结剂的表观活化能（）。此外，还提出了在加速期测得的与水化产物的钙硅比之间的相关性。通过等温量热法测试，使用两种不同方法计算不同温度下的比反应速率，从而确定所制备浆料的。当将这种新型粘结剂在加速期的与已发表的阿利特和贝利特的进行比较时，我们发现其值更高，这可能是由于形成了具有不同钙硅比的不同水化产物。最后，为了研究温度对早期抗压强度的影响，进行了一组砂浆实验。结果表明，在35℃下养护时间越长，水化2天后的抗压强度越高，这表明水化产物的初始发展程度更高。这项研究还表明，与普通硅酸盐水泥（OPC）相比，新型粘结剂对温度更敏感。
