在联合暴露于轴承负荷,流浪电流和化物入时,RC柱的退化
Igor Lapiro1, Rami Eid2, Konstantin Kovler1
1National Building Research Institute, Faculty of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa 3200003, Israel.
Materials (Basel, Switzerland)
|March 28, 2024
概括
沿海基础设施面临流浪和化物造成的严重腐蚀. 即使没有负载,流浪电流本身也会导致钢筋混凝土元素的裂.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
背景情况:
- 沿海基础设施容易受到化物引起的腐蚀.
- 来自电气系统的流失电流加剧了钢筋腐蚀.
- 现有的保护措施只能提供部分解决方案.
研究的目的:
- 调查钢筋混凝土柱子在联合负荷,化物暴露和流浪电流下降解的情况.
- 量化加速腐蚀和结构容量减少.
- 分析流浪电流对机械负荷独立的影响.
主要方法:
- 模拟服务负载,含丰富的环境和流浪电压.
- 监控降解和减轻承载能力的降解.
- 观察由于腐蚀产品造成的裂纹形成和传播.
主要成果:
- 组合的负荷,化物和流浪电流显著加快了混凝土的降解,降低了承载能力.
- 流浪电流本身,即使没有机械负荷,也会诱导拉伸应力.
- 腐蚀产品的膨胀导致了与钢筋条平行的纵向裂纹.
结论:
- 流浪电流是沿海环境中钢筋混凝土恶化的关键因素.
- 目前的保护标准对联合压力因素是不够的.
- 需要进一步的研究,以制定有效的缓解策略,防止流浪电流引起的腐蚀.
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