摘要
通过电化学阻抗谱(electrochemical impedance spectroscopy,EIS)与X射线断层扫描技术(X-ray computed tomography,X-CT),研究了电迁移氯盐加速混凝土内钢筋的腐蚀行为及钢筋-混凝土界面区的腐蚀特征。结果表明:电迁移15d后钢筋已经开始腐蚀,电迁移60d后钢筋腐蚀较严重;与混凝土基体相比,钢筋-混凝土界面区的气孔与微裂缝等缺陷处表现出较低的灰度值;钢筋-混凝土界面区的缺陷会利于Cl-诱发钢筋腐蚀,同时也能容纳更多腐蚀扩展期的腐蚀产物;EIS与X-CT的结合能够无损检测混凝土中钢筋的腐蚀行为。
The corrosion behavior of rebar in concrete accelerated by chlorides migration was investigated by electrochemical impedance spectroscopy （EIS） and X-ray computed tomography （X-CT）. The characteristic of rebar-concrete interface was also observed by using X-CT. The results reveal that corrosion initiation of rebar occurs after the chlorides migration for 15 d, and at 60 d the rebar may be subjected to severe corrosion. This indicates that the defects such as air voids and microcracks in the rebar-concrete interface result in the lower gray values, compared with the bulk concrete. The defects in the interface facilitate the corrosion initiation of rebar, as well as the accommodation of more corrosion products in the stage of corrosion propagation. As a consequence, the combined method with EIS and X-CT could be suitable to represent the corrosion behavior of rebar in concrete nondestructively.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2011年第10期1694-1700,共7页
Journal of The Chinese Ceramic Society
基金
国家“973”计划(2009CB623203)
国家“863”计划(2008-AA030704)
东南大学优秀博士学位论文基金(YBJJ1017)资助项目
关键词
钢筋腐蚀
混凝土
钢筋-混凝土界面区
氯盐迁移
电化学阻抗谱
X射线断层扫描
rebar corrosion
concrete
rebar-concrete interface
chloride migration
electrochemical impedance spectroscopy
X-raycomputed tomography
