模拟实用性研究,研究结合海沙的自压缩混凝土的冲击性能
B M Sindhurashmi1, Gopinatha Nayak2, N D Adesh3
1Department of Civil Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India.
Scientific reports
|October 21, 2024
概括
在自压缩混凝土 (SCC) 中使用非脱盐的海砂,并添加飞灰和渣,可提高耐用性. 使用50%海砂的最佳混合物显示出改善的压力强度和化物结合,这对于可持续建筑至关重要.
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:
- 自压缩混凝土 (SCC) 提供了优势,但使用非脱盐海砂作为部分细砂替代品的混合物的耐用性尚未得到充分理解.
- 三重混合 SCC 结合了补充的混凝土材料,如 F 类飞灰 (FA) 和地面颗粒高炉渣 (GGBS),需要优化用于细聚合物的替代.
研究的目的:
- 为了研究三重混合SCC的新鲜,机械,微观结构和耐久性特性,用未脱盐的海砂部分替代细砂.
- 确定粘合剂 (FA,GGBS) 和细砂 (海砂,制造砂) 的最佳混合物,以提高混凝土的性能.
主要方法:
- 制备了6种SCC变体,其中含有30%的FA,5%的GGBS,以及不同比例的海砂和制造砂.
- 测试包括一致性,设置时间,稳定性,压力强度,超声波脉冲速度和微结构分析 (SEM).
主要成果:
- 使用50%海砂和50%制造砂混合物的SCC表现出优越的90天压力强度.
- 微观结构分析显示,含有50%海砂的标本中,水合产品的密度更高,毛孔更少,并增强了弗里德尔盐的形成.
- 由于密集的-酸盐-酸盐 (C-S-H) 形成和由FA和GGBS促进的化学结合,观察到化物结合能力的改善.
结论:
- 在三重混合SCC中,用非淡化海砂 (高达50%) 部分取代制造砂是可行的,并提高机械性能和耐用性.
- 海沙,FA和GGBS之间的协同作用促进了更密集的微观结构和更好的抗化物入,提供了可持续的替代聚合物来源.
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