摘要：从煅烧温度、煅烧保温时间、粉磨细度等方面,分析不同制备工艺对氧化镁膨胀剂水化特性的影响。结果表明:在煅烧温度越高、煅烧保温时间越长以及颗粒尺寸越大的条件下,氧化镁的水化活性逐渐降低,煅烧温度超过1 100℃时,氧化镁的水化活性陡然下降;煅烧温度高且颗粒较大的氧化镁具有较大的膨胀效能,水化反应时间较长,后期将持续膨胀,最终膨胀量也较大。

关键词：氧化镁；膨胀剂；水化；大体积混凝土

Abstract： The influence of different preparing processes on hydration characteristics of magnesia expansion agent was analyzed from the aspects of calcining temperature, sintering time, and grinding fineness. The results show that the hydration activity of magnesia gradually decreases with the increasing of calcining temperature, extending of sintering time and increasing of particle size. When the calcining temperature exceeds over 1 100 ℃, the hydration activity decreases sharply. The magnesia with higher calcining temperature and larger particle size has greater expansion energy. The hydration reaction time is longer, the later expansion continues, and the final expansion amount is larger. 

Keywords: magnesia; expansion agent; hydration; mass concrete