EVA/KH560协同修改的回收混凝土机械性能 - 实验和分子动力学模拟
Weijian Wang1, Yong Feng1, Xiaoyang Li1
1Henan University of Technology, College Civil Engineering, Zhengzhou, 450001, Henan, China.
Journal of molecular graphics & modelling
|October 1, 2023
概括
回收混凝土 (RC) 的性能通过将其修改为乙烯乙酸乙烯共聚合物 (EVA) 和西兰合剂 (KH560) 来提高. 与单独使用EVA相比,这种协同修改显著改善了机械性能和接口粘合.
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:
- 回收混凝土 (RC) 需要提高长期结构应用的性能.
- 现有的RC修改方法在改善机械性能和接口完整性方面存在局限性.
研究的目的:
- 为了比较由Silane合剂 (KH560) /乙烯乙酸乙烯共聚物 (EVA) 修改的RC的强化效应与单独的EVA.
- 分析单独和协同修改对RC的机械性能,微观结构和化学成分的多层次影响.
主要方法:
- 宏观机械实验 (压力和剪切强度测试).
- 使用扫描电子显微镜 (SEM) 进行微结构分析.
- 通过X射线衍射 (XRD),里埃变换红外光谱 (FTIR) 和分子动力学 (MD) 模拟进行化学和分子分析.
主要成果:
- 协同的EVA/KH560修改产生了比单独的EVA更高的压力和剪切强度.
- 在EVA/KH560共同修改的旧/新混凝土接口上,SEM显示了表面密度的增加.
- XRD/FTIR显示出更大的水泥凝产量,而MD模拟显示了EVA/KH560修改后形成的稳定Si-O-Si键.
结论:
- 与EVA和KH560的协同修改有效地弥补了RC性能缺陷.
- 联合使用EVA和KH560可增强回收混凝土的界面粘合和机械强度.
- 修改EVA/KH560提供了一种有前途的方法,可以提高回收混凝土成员的长期性能.
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