聚氨改性聚碳酸盐对液压混凝土体积变形的影响
Shuncheng Xiang1, Yafeng Ouyang1, Jie Chen1
1Hunan Provincial Engineering Technology Research Center for Novel and Carbon Neutral Road Materia, Changsha University of Science & Technology, Changsha 410114, China.
Polymers
|February 27, 2026
概括
一种新的聚氨改性聚碳酸超塑化剂 (P-PCE) 显著减少了液压混凝土的自生和干燥收缩. 这种材料通过优化孔隙结构和减少总孔隙性来增强体积稳定性.
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.
- 混凝土技术 混凝土技术
背景情况:
- 体积变形,特别是自生和干燥收缩,是液压混凝土结构中的关键问题.
- 聚碳酸超塑化剂 (PCE) 广泛用于控制混凝土的可加工性和减少收缩,但仍在寻求进一步的改进.
研究的目的:
- 研究合成聚氨改性聚碳酸超可塑剂 (P-PCE) 对液压混凝土体积变形的影响.
- 为了比较P-PCE与传统PCE在减轻收缩和改善混凝土的微观结构性质方面的性能.
主要方法:
- 自生和干燥收缩菌株的宏观测量.
- 使用扫描电子显微镜 (SEM) 对水化产品形态进行显微镜分析.
- 低场核磁共振 (NMR) 用于量化孔隙结构.
- 碎形维度建模以将微观结构与宏观变形相关联.
主要成果:
- 与普通PCE相比,P-PCE显著降低了60天的自身收缩应变量8.8%,干燥收缩应变量8.4%.
- 随着P-PCE的添加,总毛孔度降低了19.46%.
- 通过P-PCE观察到最佳的孔隙结构分布和增强的水化产品形态.
结论:
- 实验室合成的P-PCE (40%固体含量) 有效地提高了液压混凝土的体积稳定性.
- 与传统的PCE相比,P-PCE在减少收缩和改善混凝土孔隙结构方面提供了更高的性能.
- 这些发现表明P-PCE是耐用液压混凝土应用的有希望的添加剂.
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