优化回收聚合混凝土的性能,使用化学和机械活性飞灰与子纤维结合
Tariq Ali1, Muhammad Zeeshan Qureshi2, Kennedy C Onyelowe3,4
1Department of Civil Engineering, Swedish College of Engineering and Technology, Wah, 47080, Pakistan.
Scientific reports
|March 19, 2025
概括
回收混凝土聚合物 (RCA) 的性能通过使用化学活性飞灰和子纤维来提高. 这种可持续的方法提高了混凝土的强度和耐久性,提供了绿色建筑解决方案.
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.
- 可持续建筑 可持续建筑
背景情况:
- 由于建筑垃圾,回收混凝土聚合物 (RCA) 的使用越来越多,尽管其性能低于天然聚合物 (NA).
- 研究了补充性水泥材料 (SCM) 和天然纤维,以减轻RCA的限制.
研究的目的:
- 调查天然纤维子 (CF) 和活性飞灰对回收混凝土聚合物的性能 (RCA) 的综合影响.
- 为了评估混凝土的机械性能和耐用性,采用RCA与不同的飞灰激活方法和CF含量.
主要方法:
- 测试了四种混凝土组合:对照组 (RCA不同,无飞灰),30%非活性飞灰,30%机械激活飞灰和30%化学激活飞灰.
- 天然纤维子 (CF) 被添加到百分比为0%,0.5%,1%,1.5%和2%的RCA混合物.
- 评估了机械性能 (压力和拉力强度) 和抗酸性. 扫描电子显微镜 (SEM) 用于微观结构分析.
主要成果:
- 最佳混合 (100% RCA,30% 化学活性飞灰,1.5% CF) 显示压力强度增加了25%,拉伸强度增加了17%.
- 这种优化的混合物在酸暴露下表现出最小的强度损失 (1个月后7.18%,3个月后22.14%) .
- SEM分析证实了优化的混凝土中增强的包装密度和裂填充.
结论:
- 化学活性飞灰与CF相结合,显著提高了100%RCA制成的混凝土的性能.
- 这种可持续的方法为使用回收材料生产高性能结构混凝土提供了可行的解决方案.
- 这些发现支持推进绿色建筑解决方案和建筑行业的可持续发展.
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