硅灰复合硅酸盐胶凝材料体系水化反应试验

Hydration Reaction Experiment of Composite Silicate Cementing System with Silica Fume

目的找出硅灰掺量对复合胶凝体系的水化反应以及微观结构的影响,为下一步进行复合硅酸盐胶凝体系的水化动力学研究提供参考.方法将质量分数为0、2%、5%、8%、10%硅灰掺入到硅酸盐水泥中,测试水泥浆体的水化放热速率及水化放热量,并进行XRD光谱分析和SEM扫描电镜分析.结果随着硅灰掺入量的增加,复合胶凝体系的水化诱导期延长,加速期的水化放热速率提高,二次水化放热峰的放热速率增加,减速期的水化速率损失降低,并均在掺量为8%时达到极值;当硅灰的掺量达到8%时,复合胶凝体系Ca(OH)2的生成量达到最小值.结论硅灰的加入,促进了复合胶凝体系的水化,改善了水泥石的微观结构.

The purpose of this paper is to study the effect of the content of silica fume on hydration reaction and micro structure of the composite cementitious system. Adding the quality score of 0, 2% ,5 % ,8 %, 10% silicon ash into portland cement respectively, the release rate of cement paste and hydration heat were tested and the XRD spectrum analysis and SEM analysis were carried out. It is observed that with increase of adding dosage of silicon ash, the hydration induction period of compound gel system extends; the hydration heat release rate is enhanced in the acceleration peri- od;the secondary hydration exothermic peak heat release rate increases;the hydration rate loss re- duces in the deceleration phase. When the dosage is 8 %, the values reach to extreme, and the gen- eration of composite gel system of Ca （OH） 2 is minimum. It indicates that adding of silica fume can promote hydration of composite gel system and improve the microstructure of cement stone.