通过ssDNA在活性化表面层上 anchored CNTs在岩砂混凝土中加强界面过渡区
Yi Zhou1, Taotao Cai1, Xingu Zhong1
1Hunan Provincial Key Laboratory of Structures for Wind Resistance and Vibration Control & School of Civil Engineering, Hunan University of Science and Technology, Taoyuan Road, Yuhu District, Xiangtan 411201, China.
Materials (Basel, Switzerland)
|March 14, 2026
概括
这项研究通过创建带有DNA链接的碳纳米管 (CNT) 的活性表面层 (ASL) 来增强岩砂混凝土. 这加强了接口过渡区 (ITZ),大大改善了混凝土的质量.
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:
- 岩沙提供了可持续的聚合物来源,但由于多孔的界面过渡区 (ITZ),导致混凝土易碎.
- 岩沙中的高超细颗粒含量加剧了ITZ的多孔性,限制了其机械性能.
- 解决ITZ的弱点对于在建筑中利用太阳风沙至关重要.
研究的目的:
- 通过修改ITZ来增强岩砂混凝土的机械性能.
- 为了研究活性表面层 (ASL) 与DNA功能化碳纳米管 (CNT) 结合用于ITZ增强的有效性.
- 阐明性能改进背后的微观结构机制.
主要方法:
- 使用KOH激活在岩沙上构建了一个ASL,以创建活性离子位点.
- 通过单链DNA (ssDNA) 协调,通过ASL anchored CNTs.
- 通过宏观机械测试和多尺度微观结构表征,评估了改性浮岩沙对混凝土性能的影响.
主要成果:
- 修改ASL和ssDNA/CNTs显著改善了混凝土的性能:压力强度 (+48%),屈曲强度 (+67%) 和能量消耗 (+42%).
- 微观结构分析显示,ITZ的孔隙细化,减少有害的孔隙 (>0.1微米) 从51%降至20%.
- ITZ宽度减少了67%,从20-40微米减少到10-15微米.
结论:
- ASL和ssDNA/CNT的协同效应有效地将弱的ITZ转化为加强的接口阶段.
- 分子级协调结合和优化的水泥水化产品堆叠有助于提高机械性能.
- 这种方法提供了一个可行的策略,用于生产高性能混凝土,使用可持续的地质沙资源.
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