混凝土覆盖裂纹和钢筋腐蚀行为在混凝土中与新到旧的混凝土接口
Juhui Zhang1, Jing Li1, Yuchuan Zhao2
1Department of Civil Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
Materials (Basel, Switzerland)
|September 9, 2023
概括
钢筋混凝土 (RC) 结构中的新旧混凝土接口表现出各种裂纹和钢腐蚀. 分段样本在接口处比单立体样本损失了更多的铁杆截面,影响了生统一性.
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
- 结构工程 结构工程
背景情况:
- 新到旧的混凝土接口在钢筋混凝土 (RC) 结构中常见,这些结构来自维修,拼接和建筑接头.
- 了解这些接口在腐蚀下的行为对于结构完整性和使用寿命预测至关重要.
研究的目的:
- 研究新旧混凝土接口对RC结构中的混凝土裂纹和钢筋腐蚀的影响.
- 为了在加速腐蚀条件下比较细分标本与单体标本的性能.
- 评估混凝土强度和强度差异对接口行为和铁杆腐蚀均性的影响.
主要方法:
- 制造具有不同水-水泥比率 (普通和高强度混凝土) 的单体和细分RC标本.
- 由法拉第定律控制的冲击电流加速腐蚀测试. 法拉第定律.
- 监测混凝土表面裂纹,钢铁腐蚀以及腐蚀钢的机械性能.
主要成果:
- 单立体普通混凝土显示纵向裂;高强度混凝土显示没有表面裂,只有生泄漏.
- 分段式普通混凝土呈现纵向和横向裂;高强度接口仅显示横向裂.
- 在细分样本中的钢在接口处经历了更大的切面损失,强度差异稍微增加了不均性.
结论:
- 新到旧的混凝土接口显著影响RC结构中的裂纹模式和铁杆腐蚀均性.
- 提出的影响系数可以评估接口对铁杆生均性的影响.
- 目前的模型可以预测单体标本的裂变时间,但对细分标本需要进一步研究.
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