污染水对混凝土强度和微观结构的长期影响
Sedigheh Ghasemi1, Peyman Homami2, Jafar Keyvani Ghamsari3
1Faculty of Engineering, Kharazmi University, Tehran, Iran. Std_s_ghasemi@khu.ac.ir.
Scientific reports
|July 2, 2025
概括
在混凝土中使用受污染的水进行稳定和固化 (S/S),随着时间的推移降低了机械强度,但有效地使固定不动. 这种方法对于非结构应用是可行的,只要考虑长期性能.
科学领域:
- 环境工程 环境工程
- 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.
背景情况:
- 工业活动释放有污染的废水,污染水资源.
- 使用基于水泥的材料进行稳定和固化 (S/S) 是管理污染物的关键策略.
- 了解对具体性能的长期影响对于有效的废物管理至关重要.
研究的目的:
- 研究污染的混合水对混凝土机械性能,耐用性和固定性的长期影响.
- 分析由于污染而导致的混凝土微观结构变化.
- 评估在施工中使用污染水的可行性,用于S/S应用.
主要方法:
- 准备了210个具有不同度 (00.05M) 的混凝土样本.
- 从3天到730天进行压力强度测试.
- 通过使用毒性特征的浸出程序评估浸出,并通过XRD,SEM和EDS分析微结构.
主要成果:
- 污染破坏了水泥的水化,形成了Pb (OH) 2和Pb-C-S-H相,抑制了C-S-H和CH的形成.
- 经过365天,在0.05M下观察到61%的压力强度下降,在730天后降至14MPa.
- 尽管有机械降解,但大大减少了泄漏,符合非结构性使用的环境标准.
结论:
- 污染的水可以用于S/S的受控施工,但必须考虑长期减少机械性能.
- 这项研究证明了S/S在固定混凝土中污染物的有效性.
- 使用污染水的S/S废物管理解决方案需要精心设计,以确保结构完整性和环境合规性.
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