固化条件对超高强度冲击混凝土 (UHSSC) 孔隙结构的影响,基于X射线计算机断层扫描
Shijie Xiao1,2, Jianyu Yang1, Zelin Liu1
1College of Civil Engineering, Changsha University of Science & Technology, Changsha 410076, China.
Materials (Basel, Switzerland)
|August 29, 2024
概括
这项研究使用X射线计算机断层扫描来探索超高强度冲击混凝土 (UHSSC). 自然固化产生了最高的压力强度,证明了固化条件对UHSSC性能的重大影响.
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.
- 地质技术工程 地质技术工程
背景情况:
- 冲击混凝土对于矿山和土木工程支结构至关重要.
- 使用增粘剂的超高强度冲压混凝土 (UHSSC) 提供了更好的性能.
- 了解微观结构和孔隙特征是优化UHSSC的关键.
研究的目的:
- 使用X射线计算机断层扫描 (X-CT) 在各种固化条件下研究UHSSC的微观结构.
- 分析HHSSC孔隙特性和压力强度之间的相关性.
- 评估固化方法对UHSSC性能的影响.
主要方法:
- 使用X射线计算机断层扫描 (X-CT) 重建UHSSC微结构模型.
- 孔隙特征的分析 (孔隙性,孔隙大小,球形性,定向性).
- 灰色理论的应用与孔隙参数与压力强度相关联.
主要成果:
- UHSSC 呈现出较小的孔隙性和孔隙大小,压力强度显著提高.
- 自然固化导致了最高的压力强度 (95.8 MPa) 由于更高的水合,尽管增加了多孔性.
- 较大的孔径 (≥5000微米) 和特殊形状的孔径 (S < 0.4) 与降低的UHSSC强度有很强的相关性.
结论:
- 固化条件显著影响HHSSC孔隙结构和机械性能.
- 自然固化是达到高压力强度在UHSSC的最佳方法.
- 孔隙特性,特别是大而不规则的孔隙,是HHSSC强度和耐久性的关键决定因素.
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