| 摘要: |
| 对埋置钢筋的砂浆试样施加不同大小的拉应力和压应力，通过测量承载钢筋的开路电位、腐蚀电流密度和交流阻抗等，对比了拉应力和压应力对砂浆中钢筋腐蚀的影响.结果表明：钢筋腐蚀随着应力增加而明显加剧；相同荷载作用下，承受压应力钢筋的开路电位和交流阻抗值更低、腐蚀电流密度更高，表明压应力对砂浆中钢筋的腐蚀影响更为明显.通过交流阻抗解析表明，应力破坏钢筋/混凝土界面、降低钢筋极化电阻是其加剧钢筋腐蚀的主要原因，而压应力降低钢筋/混凝土界面的极化电阻较拉应力更为明显，因而它能更为显著地加剧钢筋腐蚀. |
| 关键词: 混凝土 钢筋 腐蚀 应力 交流阻抗 |
| DOI：103969/jissn1007 9629201504018 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目（51301060）;中央高校基本科研业务费专项资金资助项目（2013B03514）;水利部公益性行业科研专项经费项目（201301052）;高等学校学科创新引智计划资助项目（B12032） |
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| Corrosion Behavior of Reinforcing Steel Bars in Mortarunder Tensile and Compressive Stresses |
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FENG Xingguo1, LU Xiangyu2, CHEN Da1, YANG Yashi3, SU Xiaodong3
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1.Key Laboratory of Coastal Disaster and Defence, Ministry of Education, Hohai University, Nanjing 210098, China;2.School of Materials Science and Engineering,Jiangsu University of Science and Technology, Zhenjiang 212003, China;3.College of Harbour, Coastal and Offshore Engineering, Hohai University, Nanjing 210098, China
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| Abstract: |
| Corrosion behavior of reinforcing steel bars in mortar subjected to different magnitudes of tensile and compressive stresses was investigated with methods of open circuit potential（OCP）, linear polarization, and electrochemical impedance spectroscopy（EIS）. As the applied stress increases, the corrosion potential and impedance of the sample decrease. For the same stress magnitude, the samples under compressive stress show more negative corrosion potentials and lower impedance values than that experiencing tensile stress. Meanwhile, corrosion current density under compressive stress is much higher than that under tensile stress. EIS analysis shows that the destruction of the concrete/rebar interface under stress accounts for the degradation of corrosion resistance of rebar. Comparing with tensile stress, the same magnitude of compressive stress more severely destroys the concrete/rebar interface. Thus, the compressive stress more significantly aggravates corrosion of reinforcing steel bars. |
| Key words: concrete rebar corrosion stress electrochemical impedance spectroscopy（EIS） |
