一个由水泥,飞和钢渣粉末组成的多重水泥系统的机械性能和微观机制
Yuzhi Zhang1,2, Shujing Zhang3, Qingke Nie4,5
1Key Laboratory of Structural Health Monitoring and Control, Shijiazhuang Tiedao University, 17 North 2nd Ring East Road, Shijiazhuang 050043, China.
Materials (Basel, Switzerland)
|November 25, 2023
概括
钢渣粉 (SSP) 和飞灰 (FA) 提高了水泥糊的加工能力和机械性能. 通过用1:1的FA-SSP混合物替换40%的水泥,以0.4的水与粘合剂比率达到最佳性能.
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.
- 环境工程 环境工程
背景情况:
- 钢粉 (SSP) 是钢铁制造中的废物产品,这给处置带来了挑战.
- 像SSP这样的工业副产品的资源利用对于可持续建筑至关重要.
- 像飞灰 (FA) 这样的补充性水泥材料 (SCM) 用于增强混凝土的性能和减少对环境的影响.
研究的目的:
- 研究钢粉 (SSP) 作为复合水泥糊中的补充水泥材料的潜力.
- 评估SSP和FA对水泥材料宏观机械性能和微观结构的影响.
- 为了确定在建筑应用中使用SSP和FA的最佳混合比例.
主要方法:
- 用SSP和FA制备复合水泥糊样本,其水与粘合剂比率和水泥替代率各不相同.
- 宏观性质测试包括设置时间,流动性,屈曲强度和压力强度.
- 使用X射线衍射 (XRD),扫描电子显微镜 (SEM) 和Image Pro Plus (IPP) 进行定量孔分析的微结构分析.
主要成果:
- 添加FA和SSP通过延迟水化水泥,提高了糊的流动性.
- 增加水与粘合剂比率降低了样品强度.
- 在较晚的阶段,在20%的SSP替代下观察到最佳的机械强度.
- 微结构分析显示,通过FA-SSP添加剂的C-S-H凝和RO相减少了AFt晶体和孔隙填充.
- 最好的性能是在40%,FA-SSP比为1:1的水与粘合剂比为0.4的水替换水泥时获得的.
结论:
- 在建筑中,SSP和FA可以有效地被用作补充的水泥材料.
- 该研究为SSP和FA在水泥系统中的实际应用提供了理论基础.
- 优化的混合设计可以提高结合这些废物材料的硬化水泥的性能.
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