研究早期水合,机械特性发展和微观结构的演变,制造的砂混凝土与花岩石粉混合
Jianghua Wang1,2, Cuizhen Xue1,2, Yu Zhang1,2
1College of Civil Engineering, Lanzhou University of Technology, Lanzhou 730050, China.
Materials (Basel, Switzerland)
|July 14, 2023
概括
作为补充水泥材料 (SCM) 的花岩石粉 (GSP) 延迟了水化,降低了混凝土的强度,特别是在更高的百分比下. 大孔显著影响机械性能,但预测模型显示高精度.
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.
- 建筑材料 建筑材料
背景情况:
- 补充性水泥材料 (SCM) 对于可持续的混凝土生产至关重要.
- 花岩石粉 (GSP) 是一个潜在的SCM,但它对混凝土性能的影响需要彻底调查.
- 了解GSP修改混凝土的水分和机械行为对于其实际应用至关重要.
研究的目的:
- 探索使用花岩石粉 (GSP) 作为补充水泥材料 (SCM) 的可行性.
- 分析GSP混合水泥泥的早期水化过程.
- 研究采用GSP的制造砂混凝土 (MSC) 的机械性能和微观结构演变.
主要方法:
- 使用X射线衍光度,扫描电子显微镜和侵入孔径测量来分析物理相,形态和孔隙结构.
- 原子力显微镜 (AFM) 量化了接口过渡区 (ITZ) 的粗度.
- 用灰色分析和GM (1,1) 灰色模型来评估孔径大小的影响和预测机械强度.
主要成果:
- 纳入GSP改变了水合率,显示5%的轻微增长和15%的GSP下降.
- 随着GSP含量的增加,MSC的机械性能下降,在10-15%的GSP中观察到显著下降.
- 增加的孔隙性和ITZ粗性被注意到,较大的孔隙 (>1000nm) 显著影响机械强度 (灰色相关性> 0.86).
结论:
- 虽然GSP可以用作SCM,但其应用需要仔细考虑内容,因为它会对机械性能产生负面影响.
- 该研究提供了对GSP修改混凝土微观结构变化和毛孔结构演变的见解.
- 一个经过验证的GM (1,1) 模型为机械强度提供了准确的预测,支持基于数据的GSP使用规范开发.
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