In this work, the negative impacts of calcium sulfoaluminate (CSA) cement prehydration on hydration and strength gain are investigated. CSA cement in three different states – virgin, prehydrated, and prehydrated and sieved were tested. Cement paste mixtures were made with three levels of ordinary portland cement (OPC) – 0%, 30%, and 70% (indicating the percentage of OPC in total cementitious material) at a water-to-cementitious materials ratio of 0.40. CSA cement prehydration causes an increase in the particle size measured by laser diffraction, the presence of elongated particles in the electron micrograph, and the detection of hydrated and carbonated phases using thermogravimetric analysis. Prehydration of CSA cement has detrimental effects on hydration and strength gain on CSA-OPC mixtures, with exact effects depending strongly on the OPC level in the cement paste. In mixtures with 70% OPC, the effect of prehydration is pronounced – heat release of the mixture with virgin CSA cement at seven days is 33% higher than in the mixture with prehydrated CSA cement and the corresponding strength at 28 days is 198% higher. Relationships between heat release, bound water, and compressive strength and the effect of prehydration on these relationships were also explored. Sieving the prehydrated CSA cement before use presents some limited benefits in the reducing the detrimental effects of prehydration.

在这项工作中，研究了硫铝铝酸钙（CSA）水泥预水合对水合和强度增加的负面影响。测试了三种不同状态的CSA水泥-原始，预水合，预水合和筛分。水泥浆混合物使用三种含量的普通硅酸盐水泥（OPC）– 0％，30％和70％（指示OPC在全部胶结材料中的百分比）进行制造，水胶结材料比率为0.40。CSA水泥预水合会导致通过激光衍射测量的粒径增加，电子显微照片中拉长的颗粒的存在以及使用热重分析检测水合相和碳酸盐相。CSA水泥的预水合会对CSA-OPC混合物的水合和强度增加产生不利影响，确切的效果在很大程度上取决于水泥浆中的OPC含量。在OPC含量为70％的混合物中，预水合效果显着–与纯CSA水泥的混合物在7天时的热释放比与预水合CSA水泥的混合物中的热释放高33％，而在28天时的相应强度则高198％。还探讨了放热，结合水和抗压强度之间的关系以及预水合作用对这些关系的影响。在使用前筛分预水合的CSA水泥在减少预水合的有害影响方面显示出一些有限的好处。预水化的效果是很明显的-与纯CSA水泥混合的混合物在7天时的热释放比与预水合CSA水泥混合的混合物高33％，而在28天时的相应强度高198％。还探讨了放热，结合水和抗压强度之间的关系以及预水合作用对这些关系的影响。在使用前筛分预水合的CSA水泥在减少预水合的有害影响方面显示出一些有限的好处。预水化的效果是很明显的-与纯CSA水泥混合的混合物在7天时的热释放比与预水合CSA水泥混合的混合物高33％，而在28天时的相应强度高198％。还探讨了放热，结合水和抗压强度之间的关系以及预水合作用对这些关系的影响。在使用前筛分预水合的CSA水泥在减少预水合的有害影响方面显示出一些有限的好处。