1.同济大学材料科学与工程学院;2.云南氟业环保科技股份有限公司
国家自然科学基金项目（面上项目，重点项目，重大项目）
1.School of Materials Science and Engineering, Tongji University, Shanghai;2.Yunnan Fluorine Environment Protect Technology Co., Ltd
本实验就硫酸镁（MgSO4）和三乙醇胺（TEA）两种早强组分对含有二乙醇胺（DEA）的硫酸铝溶液的储存稳定性、该溶液对水泥浆体凝结时间和水泥砂浆强度的影响，进行了系统研究，并将含有DEA的硫酸铝溶液与MgSO4、TEA进行复配，制备了无氟无氯无碱液体速凝剂（LA），测试了其综合性能，利用水化热、X射线衍射、热重等分析手段，探明了LA的作用机理。结果表明：低用量下，MgSO4和TEA均能增强硫酸铝溶液的早强效果；掺加LA能显著缩短水泥浆体凝结时间，提高水泥砂浆早期抗压强度；LA通过促进硬化浆体中早期钙矾石晶体的形成，加速液相中骨架形成，促进浆体快速凝结硬化，发展早期强度。
The effects of triethanolamine (TEA) and magnesium sulfate (MgSO4) on the storage stability of aluminum sulfate solution with diethanolamine (DEA), and the solution on the setting time of cement slurry and the strength of cement mortar were systematically studied in this experiment. And the aluminum sulfate solution with DEA was compounded with MgSO4 and TEA to determine the ratio of the final fluorine-free, chlorine-free and alkali-free liquid accelerator (LA), and its comprehensive properties were tested. And the mechanism of LA was clarified by heat of hydration, X-ray diffraction, thermogravimetric and other analytical methods. The results showed that MgSO4 and TEA could improve the early strength effect of the accelerator at low dosage; LA can significantly shorten the setting time of cement slurry and improve the early compressive strength of cement mortar. LA accelerates the formation of skeleton in the liquid phase by promoting the formation of early ettringite crystals in the hardened slurry, promoting the rapid setting and hardening of the slurry, and developing early strength.
