Properties and microstructure of alkali-activated cementitious materials prepared with carbide slag-slag-fly ash solid waste

被引：0
|
作者：
Gao Y. [1 ]
Meng H. [1 ]
Wan H. [2 ]
Hu X. [1 ]
Chen C. [1 ]
机构：
[1] School of Traffic and Transportation Engineering, Changsha University of Science and Technology, Changsha
[2] Changsha Wanrong Powder Equipment Technology Co. Ltd., Changsha
来源：
Zhongnan Daxue Xuebao (Ziran Kexue Ban)/Journal of Central South University (Science and Technology) | 2023年 / 54卷 / 05期
基金：
中国国家自然科学基金;
关键词：
alkali-activated materials; carbide slag; fluidization vortex; microstructure; solid waste;
D O I：
10.11817/j.issn.1672-7207.2023.05.009
中图分类号：
学科分类号：
摘要：
The industrial solid waste was modified by fluidization vortex technology. The modified carbide slag was used as alkaline activator, and the modified slag-fly ash was used as silicon-aluminum material to prepare the alkali-activated cementitious materials for all solid waste. The hydration mechanism and microstructure were investigated by means of mercury intrusion porosimetry(MIP), hydration heat measurement, X-ray diffraction(XRD), scanning electron microscopy(SEM) and energy dispersive spectroscopy(EDS). The results show that fluidization vortex technology has excellent physical and chemical modification effect on industrial solid waste, which makes the solid waste materials have higher reaction activity. The alkali-activated materials made of modified materials have better mechanical properties and pore size distribution, and their 7 d and 28 d compressive strengths can reach 22.4 MPa and 37.8 MPa, respectively. Modified carbide slag releases more calcium hydroxide, and provides alkaline environment and calcareous components. Modified slag-fly ash provides silicon-aluminum components, and generates hydration products mainly composed of C-S-H, C-A-S-H gel and tobermorite. The hydration products are closely combined with a small amount of raw materials to form a stable structure, which makes the cementitious materials have good mechanical properties. © 2023 Central South University of Technology. All rights reserved.
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页码：1739 / 1747
页数：8
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