通过酶诱导碳酸沉 (EICP) 修复的裂纹混凝土的实验研究
Gang Li1, Deqiang Yan1, Jia Liu1
1Shaanxi Key Laboratory of Safety and Durability of Concrete Structures, Xijing University, Xi'an 710123, China.
Materials (Basel, Switzerland)
|July 13, 2024
概括
本研究提出了一种环保方法,使用微生物诱导的沉 (EICP) 来修复混凝土裂. 通过在裂中形成持久的碳酸晶体,EICP有效地恢复了混凝土的强度和使用寿命.
科学领域:
- 材料科学与工程 材料科学与工程
- 土木工程 土木工程是指土木工程.
- 环境科学 环境科学
背景情况:
- 由于裂而导致的混凝土基础设施退化需要有效的修复方法.
- 现有的维修技术往往缺乏环境可持续性或长期有效性.
- 微生物诱导的沉 (EICP) 为裂修复提供了一个有前途的基于生物的方法.
研究的目的:
- 评估一个环保的EICP方法修复混凝土裂的有效性.
- 使用EICP调查混凝土的内部修复机制和性能提升.
- 评估使用EICP修复的混凝土结构的使用寿命延长.
主要方法:
- 使用EICP注射法用石英砂修复了带有诱导裂纹的混凝土样本.
- 使用超声波测试和压力强度测试来评估内部修复的有效性.
- 能量分散式X射线光谱 (EDS),X射线衍射 (XRD) 和扫描电子显微镜 (SEM) 用于识别修复机制.
主要成果:
- 在破裂的混凝土样本中,EICP修复显著减少了超声波传输时间.
- 在修复后,0.3毫米宽的裂的压力强度恢复达到了98.41%.
- 形成的主要矿物质是瓦特里特 (碳酸),它紧紧地附着在裂表面上.
结论:
- EICP注入方法是一种低碳,环保,有效的技术,用于修复混凝土裂.
- 瓦特里特晶体的形成有助于裂的紧密和均密封,提高了混凝土的耐用性.
- 该研究表明,EICP有潜力延长混凝土结构的使用寿命.
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