用微封装相变材料修改的混凝土的机械性能和冷耐用性
Zhitao Zheng1,2, Wenbing Shen3,4, Sheng Li1
12nd Construction Co.,LTD Of China Construction 5th Engineering Bureau, Hefei Anhui, 230041, China.
Scientific reports
|August 11, 2025
概括
将微封装相变材料 (mPCM) 添加到混凝土中,可以提高强度和抗解的性能. 使用6%的mPCM可以达到最佳性能,在寒冷的气候中增强耐用性.
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:
- 在寒冷的气候下,混凝土容易受融损伤.
- 阶段变换材料 (PCM) 提供热能调节,但需要对恶劣的混凝土环境进行保护.
- 微封装保护PCM,并允许它们作为混凝土添加剂进行集成.
研究的目的:
- 调查微封装相变材料 (mPCM) 对混凝土机械性能和解耐力的剂量依赖影响.
- 确定最佳的mPCM含量,以提高混凝土在寒冷气候中的耐用性.
- 阐明mPCM对混凝土性能影响背后的微结构机制.
主要方法:
- 在不同剂量 (0-12%的水泥替代) 中系统地纳入mPCM.
- 综合性机械测试 (压力,曲,分裂拉伸强度).
- 100 周期加速冷解测试.
- 定量微结构分析 (孔隙结构评估).
主要成果:
- 与对照混凝土相比,添加了6%的mPCM显著改善了压力 (8.90%),柔性 (19.23%) 和分裂拉伸强度 (30.72%).
- 使用6%mPCM的混凝土表现出极好的耐用性,在100个融周期后,只有1.6%的质量损失和<15%的强度降解.
- 微结构分析显示,6%的mPCM通过减少孔径来优化孔隙结构,提高结解的抵抗力.
- 剂量超过9%的mPCM导致混凝土矩阵减弱,整体强度降低.
结论:
- 对于寒冷气候的混凝土中mPCM的最佳剂量是6%的水泥替代品.
- 这种剂量通过相变特性提供了机械承载能力和热应力减轻的协同增强.
- 这些发现为在易受融周期影响的地区设计耐用,高性能混凝土结构提供了实际指导.
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