无碱液体速凝剂作用机理研究  

Study on Action Mechanism of Alkali-Free Liquid Acceleretor

作　　者：杨富民 YANG Fumin(Beijing Tieke Shougang Rail-Tech.Co.Ltd.,Beijing 102206,China)

机构地区：[1]北京铁科首钢轨道技术股份有限公司,北京102206

出　　处：《铁道建筑》2021年第2期139-142,共4页Railway Engineering

摘　　要：借助热重分析、差热分析、X射线衍射图谱、扫描电子显微镜微观形貌等手段,对比掺加无碱液体速凝剂前后的水泥水化产物,研究无碱液体速凝剂的促凝及增强机理。结果表明:掺加无碱液体速凝剂后,水泥浆体在3 min内生成大量的高硫型水化硫铝酸钙(AFt),促使水泥浆体迅速达到初凝和终凝;无碱液体速凝剂促使水泥浆体早期生成大量AFt,形成空间网络结构,水化28 d后大量的AFt转化成低硫型水化硫铝酸钙(AFm),结构更为致密,从而使得水泥砂浆具有较高的早期和后期强度。By means of thermo gravimetric analysis,differential thermal analysis,X-ray diffraction pattern and scanning electron microscope,the hydration products of cement before and after adding alkali-free liquid accelerator were compared,the accelerating mechanism and the reinforcing mechanism of alkali-free liquid accelerator were studied.The results show that after adding alkali-free liquid accelerator,a large amount of AFt is produced in cement paste in 3 minutes,which promotes the cement paste to reach the initial setting and final setting rapidly.Alkali-free liquid accelerator promotes the cement paste to generate a large amount of Aft in the early stage,forming a spatial network structure.After 28 days of hydration,a large amount of AFt is transformed into AFm with a denser structure,which makes the cement mortar have higher early and late strength.

关 键 词：无碱液体速凝剂 促凝机理 试验研究 增强机理 X射线衍射图谱 微观形貌 

分 类 号：TU528[建筑科学—建筑技术科学]