| 摘要: |
| 通过水泥浆水化反应、新拌混凝土流变性能与硬化试块的力学性能试验，研究了纳米气泡水（NBW）拌合混凝土工作性改善及抗压强度提高的规律，并探讨了其形成机理．结果表明：NBW对C25以下强度等级混凝土拌合物的流动性和硬化试块的抗压强度改善不显著，但可提高C30以上强度等级混凝土拌合物的流动性并显著抑制其坍落度经时损失，且7、28d龄期试块的抗压强度均有不同程度增长．这是因为NBW富含纳微级气泡，可促进拌合物中骨料浆面层的滚珠润滑作用，提升介观粗细料层浆体流动稳定性，进而改善拌合物的宏观工作性能；同时微细气泡表面的ζ电位具有高强吸附力，增加了拌合物溶液中离子的成核位点数量，有利于水泥早期有效水化产物的增加. |
| 关键词: 混凝土拌合物 纳米气泡水 流动性 水化反应 抗压强度 |
| DOI：103969/j.issn1007 9629202002006 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目(51879094)；江苏省优势学科建设项目(SYS1401) |
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| Proporties of Concrete Mixed by Nano bubble Water |
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TIAN Zhenghong1, JIAO Xincheng1, YANG Hangang2, LI Ang1
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1.College of Conservancy and Hydropower, Hohai University, Nanjing 210098, China;2.Guolangqiao Project, Sino Hydro Bureau 7 Co., Ltd., Yaan 625503, China
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| Abstract: |
| Through the experimental analysis of hydration process, the flow property of fresh concrete and the mechanical property of hardened concrete, the improving workability and compressive strength of concrete mixed with nano bubble water（NBW） were studied, and its mechanism of action was explored. Experimental research shows that NBW does not significantly improve the flow ability and compressive strength of concrete of grade below C25.However, when compressive strength is over C30, NBW can significantly enhance the flow ability of fresh concrete, and the slump loss over time is obviously reduced. In addition, the compressive strength of hardened concrete at 7, 28d has increased at some extent. The mechanism of the test results is that the NBW plays role of ball lubrication in aggregate slurry surface of fresh concrete, and enhances the flow stability between the coarse and fine layer and, furthermore, improves the workability of fresh concrete. In addition, high potential ζ on the surface of single bubble has high ability of adsorption and increases ion seeding quantities in the solution and increases the effective cement hydration product. |
| Key words: concrete mixture nano bubble water flow property hydration reaction compressive strength |
