高性能材料改善了制造砂混凝土的早期收缩,早期破裂,强度,透性和微观结构
Mingming Zhang1,2, Shan Gao3, Tong Liu2
1School of Civil Engineering, Xijing University, Xi'an 710123, China.
Materials (Basel, Switzerland)
|May 25, 2024
概括
工程师可以通过添加飞灰和渣粉 (FS),减少收缩剂 (SRA),聚乙醇 (PVA) 纤维和超吸收聚合物 (SAP) 来提高混凝土的早期性能. 这些添加剂显著减少收缩和裂纹,尽管SRA和SAP可能会降低后来的强度.
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:
- 制造砂,废粉和回收聚合混凝土中的早期收缩和裂纹不良,阻碍了工程应用.
- 解决这些局限性对于可持续混凝土材料的广泛采用至关重要.
研究的目的:
- 为了研究将飞灰和渣粉 (FS),减少收缩剂 (SRA),聚乙醇 (PVA) 纤维和超吸收聚合物 (SAP) 纳入大量石粉制造砂混凝土的有效性.
- 评估这些添加剂对早期收缩,裂,强度和性以及微观结构和孔隙结构特征的影响.
主要方法:
- 对混凝土混合物进行了早期的收缩,裂,强度和透性测试.
- 利用核磁共振 (NMR) 和扫描电子显微镜 (SEM) 来分析微观结构和孔隙结构.
主要成果:
- 结合使用FS,SRA,PVA纤维和SAP,有效地抑制了收缩应变 (SAP降低高达76.49%) 和裂纹面积 (PVA纤维降低高达66.91%).
- FS提高了颗粒分级和混凝土的紧性. 乙烯纤维增强了粘合,减少了水损失.
- 虽然SRA和SAP减少了早期的收缩和裂纹,但由于分别增加了微孔和剩余孔,它们对以后的强度和透性产生了负面影响.
结论:
- 一种FS,SRA,PVA纤维和SAP的协同混合物可以显著提高制造的砂混凝土的早期性能.
- 聚乙烯纤维和FS在强度和透性方面具有优势,而SRA和SAP在长期性能方面具有缺点.
- 优化添加剂组合是平衡早期性能改进与可持续混凝土应用中的长期耐用性的关键.
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