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探索微波影响下的超高性能混凝土微结构变化的机制:实验和分子动力学模拟
Jingyuan Chen1, Kunyang Yu2, Shuangxin Li1
1School of Civil Engineering and Transportation, Northeast Forestry University, Harbin 150060, China.
Materials (Basel, Switzerland)
|May 14, 2025
概括
微波固化通过减少孔积和增强酸水合物 (C-S-H) 凝结构,显著改进了超高性能混凝土 (UHPC) 微结构. 这导致了一种更紧的材料,其拉伸强度提高到1GPa.
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.
- 纳米技术 纳米技术
背景情况:
- 超高性能混凝土 (UHPC) 需要优化的微结构性质,以提高耐用性和性能.
- 了解微波暴露等新固方法的影响对于推进混凝土技术至关重要.
研究的目的:
- 在微波固化下研究UHPC的微结构演变.
- 阐明微波引起的水化产品和毛孔结构变化背后的机制.
- 量化对机械性能的影响,特别是抗拉强度.
主要方法:
- 使用入孔径测量 (MIP),X射线衍射 (XRD) 和扫描电子显微镜 (SEM) 的多尺度表征.
- 分子动力学 (MD) 模拟来分析酸水合物 (C-S-H) 凝的行为,包括单轴拉伸特性和自由体积.
- 孔隙结构,水化产品,形态和接口过渡区 (ITZ) 的分析.
主要成果:
- 微波固化显著减少毛孔体积,早期平均每日减少0.15%,减少高风险毛孔.
- 水化产品呈现出更高的密度和优化的内孔结构.
- MD模拟表明非热微波效应促进C-S-H凝中的分子排序,驱逐自由体积并增加拉伸强度高达1GPa.
结论:
- 微波固化提供了一种有效的方法,可以加速UHPC微观结构的提炼和增强机械性能.
- 微波的非热效应是UHPC结构演变的关键驱动因素.
- 该研究提供了对微波诱导的UHPC改进的多层次理解.
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