石膏种类对硅酸盐水泥性能的影响

通过对原材料特性、水泥物理力学性能、水泥水化产物扫描电镜分析等方面的分析试验,研究了不同种类的石膏对硅酸盐水泥性能和水化过程的影响。结果表明:掺加硬石膏的水泥与掺加二水石膏的水泥相比,强度有所降低;半水石膏使硅酸盐水泥标准稠度用水量增大,并且其早期强度较低,不符合国家标准;在水泥中加入磷石膏做缓凝剂,对凝结时间影响较大,但对强度影响不太明显;氟石膏作水泥缓凝剂有良好的效果,水泥强度符合要求,对水泥性能未见不良影响。

Effects of Different Kinds of Gypsum On Properties of Portland Cement

The effects of different gypsum on portland cement properties and hydration process were investigated through analysis testings on raw materials property, cement physicomechanical property and hydration product by SEM. Test results show that cement strength would be decreased when adding anhydrite than adding dihydrate gypsum. The cement which added with semi-hydrated gypsum need more water, but less strength is obtained in early stage. Phosphorous gypsum makes cement condensation time prolonged, while give no evidence influence on cement strength. Using fluorine gypsum as retardant, good effect has obtained on cement strength and no defect is found on cement properties.