用弱活性激活剂激活的性激活砂水泥的特性
Juan He1, Shuya Yu1, Guochen Sang2
1College of Materials Science and Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
Materials (Basel, Switzerland)
|May 27, 2023
概括
这项研究优化了使用硫酸和碳酸激活剂与氧化和氧化的活性渣 (AAS) 水泥. 与普通波特兰水泥相比,新配方提高了机械性能,降低了成本和二氧化碳排放.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 可持续建筑 可持续建筑
背景情况:
- 活性渣泥 (AAS) 提供了诸如低收缩率等优势,但其机械性能发展缓慢.
- 弱性激活剂,如硫酸 (Na2SO4) 和碳酸 (Na2CO3) 提供长时间的设置时间,但需要优化强度.
- 反应性氧化 (MgO) 和氧化 (Ca(OH) 2) 正在作为共同激活剂来改善AAS水泥性能.
研究的目的:
- 为了优化AAS水泥的定时间和机械性能,使用Na2SO4,Na2CO3,MgO和Ca (OH) 2.
- 为了研究优化的AAS水泥的水化产品和微观结构形态.
- 与传统材料相比,评估开发的AAS水泥的生产成本和环境效益.
主要方法:
- 使用Na2SO4和Na2CO3作为主要激活剂,与活性MgO和Ca (OH) 2相结合,制备了活性废渣 (AAS) 水泥.
- 使用X射线衍射 (XRD),扫描电子显微镜 (SEM) 和能量分散式X射线光谱 (EDS) 来分析水化产品和微观结构.
- 机械性能 (柔性和压力强度) 和设置时间被系统评估.
主要成果:
- 氧化 (Ca(OH) 2) 通过与Na2CO3反应形成CaCO3,加速初始设置,从而显著影响设置时间.
- 硫酸 (Na2SO4) 和碳酸 (Na2CO3) 的含量对分别曲和压力强度的发展至关重要.
- 最佳的激活剂组成 (7% Na2SO4,4% Na2CO3,3-5% Ca(OH) 2,2-4%的活性MgO) 平衡了设置时间和机械强度.
- 高反应性MgO含量缩短了设置时间,增强了28天的强度.
- 化产品表现出增加的晶体相.
结论:
- 优化的AAS水泥配方表现出改进的机械性能和受控的定时间.
- 这种低性激活AAS水泥可以大幅降低生产成本,能源消耗和二氧化碳排放 (比OPC减少78.1%).
- 开发的AAS水泥为普通波特兰水泥 (OPC) 提供了一个可持续和经济可行的替代方案.
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