热活性煤聚合物混凝土界面过渡区演变和故障机制的多层次调查
Jie Zhou1, Shengpeng Hao2,3, Yong Chen4
1Lanzhou Coal Mine Design and Research Institute Co., Ltd, Lanzhou, 730000, China.
Scientific reports
|August 6, 2025
概括
在700-800°C的煤 (CG) 的热激活通过增强界面过渡区 (ITZ) 来提高混凝土的强度. 这种可持续的方法利用废弃的CG作为高性能混凝土聚合物.
科学领域:
- 材料科学与工程 材料科学与工程
- 土木工程 土木工程是指土木工程.
- 环境工程 环境工程
背景情况:
- 大规模的煤炭 (CG) 积累带来了环境和土地利用问题.
- 直接使用CG作为混凝土聚合物受限于反应性差,高孔隙性和弱的界面粘合.
- 烧焦温度对CG聚合物的性能和混凝土性能的影响需要进一步的多尺度调查.
研究的目的:
- 为了研究热激活对煤聚合物混凝土的多尺度效应.
- 阐明化温度对界面过渡区 (ITZ) 演变和故障机制的影响.
- 在具体的应用中,为煤炭的可持续价值化提供见解.
主要方法:
- 在500,600,700和800°C烧焦的煤,作为C30混凝土的聚合物.
- 实验分析包括单轴压缩测试,扫描电子显微镜 (SEM),X射线衍射 (XRD) 和核磁共振 (NMR).
- 粒子流代码3D (PFC3D) 用于中等尺度模拟裂的启动和传播.
主要成果:
- 在700-800°C的化优化了活性SiO2/Al2O3的释放,导致更密集的ITZ和较低的孔隙性.
- 与未加混凝土相比,混凝土使用热激活的CG聚合物显示,28天的压力强度增加了15.6-22.8%.
- 中尺度模型表明,增强ITZ债券强度延迟了裂的开始,改变了损伤模式.
结论:
- 热激活显著提高了煤作为混凝土聚合物的性能.
- 最佳的化温度 (700-800°C) 可以改善ITZ的微观结构,降低孔隙性,增加压力强度.
- 这项研究提供了一个框架,用于利用煤炭废弃物在可持续的高性能混凝土中.
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