含不同石膏种类的超硫酸盐水泥的水化行为

Hydration Behavior of Super Sulphated Cement with Different Types of Gypsum

摘要:

针对不同石膏对超硫酸盐水泥水化行为的影响，测试了分别掺有硬石膏、二水石膏和磷石膏的超硫酸盐水泥的各龄期抗压强度，对比了其早期放热速率及放热曲线的差异，以及水化产物相的变化.结果表明：上述3类超硫酸盐水泥3d抗压强度均为14MPa左右；磷石膏基超硫酸盐水泥28，90d抗压强度分别为412，491MPa，明显高于其他两种水泥.超硫酸盐水泥早期强度主要受水化速率的影响.后期强度测试结果表明，磷石膏的激发效果优于硬石膏及二水石膏，用其制备的水泥浆体后期形成更多的水化硅酸钙与钙矾石，硬化浆体更加密实.

Abstract:

In order to elucidate the hydration behavior of super sulphated cement（SSC） with different types of gypsum, influence of anhydrite, dihydrate gypsum, and phosphogypsum on the cement paste compressive strength of various age of SSC were tested；furthermore, hydration exothermic rate, hydration heat and hydration products were systematically compared. Results show that 3 day strength of all samples is about 14MPa；however, phosphogypsum based SSC of the compressive strength 412MPa at 28 days and 491MPa at 90 days is significantly higher than other samples. Early strength mainly depends on hydration heat rate of different samples, later strength is due to the better activation effect of phosphogypsum than anhydrite and dihydrate gypsum, SSC paste with phosphogypsum could generate more C S H and ettringite in late stage with relatively higher density than other samples.