石膏对水泥与外加剂适应性的影响

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1、摘要本论文针对实际工程中经常出现的水泥与外加剂，尤其是高效减水剂之间的不适应问题，主要从石膏方面研究了造成水泥与高效减水剂适应性差的原因。在对石膏、高效减水剂及水泥等主要原材料基本性能分析的基础上，通过测试水泥的物理力学性能、水泥水化产物的微观特性，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：对于选出的物理力学性能较好的水泥，用测试净浆流动度的方法评定其与四种常用高效减水剂的适应性；通过测定掺不同种类石膏的水泥对不同高效减水剂的吸附量、在不同浓度高效减水剂溶液中的(电位和水化溶液的电阻率，进一步解释和分析造成水泥与高效减水剂适应性不同的原因和机理。本论

2、文的研究结果表明，用不同种类的石膏做调凝剂时，硅酸盐水泥的性能有较大差别，力学强度由大到小的顺序为：二水石膏、氟石膏、磷石膏、硬石膏、半水石膏，半水石膏对早期强度影响较大，而磷石膏缓凝效果过强。对于硅酸盐水泥，适宜的调凝剂为二水石膏、氟石膏和硬石膏。掺加不同种类石膏的水泥与四种常用高效减水剂之间的适应性不同，掺加二水石膏的水泥与共聚羧酸高效减水剂具有优异的适应性，表现在初始流动度较大，经时损失较小，具有明显的饱和点且饱和掺量较小，丽掺加硬石膏的水泥与萘系高效减水剂的适应性相对较差，主要表现为饱和点不明显，泌水现象严重。关键词石膏；水泥；高效减水剂；适应性Abst

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