硫酸铝类无碱速凝剂促凝机理研究  

Study on Accelerating Mechanism of Aluminum Sulfate-based Alkali-free Accelerator

作　　者：关业程 沈卫国[1,2] 李志堂 许伟 吴定略 孙江涛 GUAN Ye-cheng;SHEN Wei-guo;LI Zhi-tang;XU Wei;WU Ding-lue;SUN Jiang-tao(State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan 430070,China;School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China;Poly Changda Engineering Co Ltd,Guangzhou 510000,China)

机构地区：[1]武汉理工大学硅酸盐建筑材料国家重点实验室,武汉430070 [2]武汉理工大学材料科学与工程学院,武汉430070 [3]保利长大工程有限公司,广州510000

出　　处：《武汉理工大学学报》2021年第4期1-5,共5页Journal of Wuhan University of Technology

基　　金：十三五国家重点研发计划(2016YFB0303603);2016年湖北省交通厅公路管理局科技项目。

摘　　要：通过设计加入速凝剂的水泥净浆实验组和不加速凝剂的空白组两组试验,探究速凝剂对水泥水化的影响作用机理并通过XRD和SEM等手段从微观层面上对水泥水化进程进行表征。XRD试验结果表明,由于速凝剂的加入,水泥在5min之内的水化产物已经可以观察到AFt的衍射峰,并且SEM图中可以观察到大量的针棒状AFt,而空白组在水化2h后才能观察到AFt。这表明硫酸铝类无碱速凝剂是通过引入Al^(3+)来加速C_(3)A的早期水化反应,在短时间内生成大量AFt从而导致水泥速凝。We designed two sets of experiments in the cement paste experimental group with accelerators and the blank group without accelerators to explore the mechanism of the effect of accelerators on cement hydration,and also used XRD and SEM methods from the microscopic level to characterize the progress of cement hydration.The XRD test results show that due to the accelerator,the hydration product of cement within 5 minutes can already observe the diffraction peak of AFt,and a large number of needle-shaped AFt can be observed in the SEM image,while the blank group is hydrated.AFt can only be observed after 2 h,which shows that aluminum sulfate-based alkali-free accelerators accelerate the early hydration reaction of C_(3)A by introducing Al^(3+),and generate a large amount of AFt in a short time,which leads to cement quicksetting.

关 键 词：硫酸铝 无碱速凝剂 促凝机理 钙矾石 水化产物 

分 类 号：TU528[建筑科学—建筑技术科学]