腐蚀介质中混凝土/钢筋界面电极电位分布的立体分析

由于混凝土的隔离和高绝缘性 ,常规的电化学技术、微探针扫描技术均难于获得在腐蚀介质的浸泡下混凝土 /钢筋界面 ,特别是不同深处的混凝土 /钢筋界面的电位分布 .本文提出用阵列电极法并结合电子技术和微机控制技术 ,获得同一水平面上混凝土 /钢筋界面以及不同深处的混凝土 /钢筋界面的电位分布立体信息图 .结果表明 :在NaCl介质中经过一段时间的浸泡 ,混凝土中的钢筋腐蚀可发生并发展 ;而在Na2 SO4 介质中经过一段时间的浸泡 ,虽钢筋腐蚀一般不发生 ,但混凝土可能破坏 .不同深处混凝土 /钢筋界面腐蚀优先发生在混凝土覆盖较浅的部位 .

An Investigation on the Corrosion Potential Imaging at the Interface of Concrete/Reinforcing Bar in Corrosion Media

The iron array electrode covered with concrete as a new electrochemical technique is applied to map the potential imaging and to investigate on the iron electrode corrosion process under concrete: In Cl - solution the corrosion of the iron array electrode covered with concrete had been prevented for a short term since the concrete protection, but the corrosion still occurreed and developed after immersed for a long time. In SO 4 2- solution although the sample had being immersed for a long time and the concrete was possibly broken, the corrosion did not develop. In Cl - solution the corrosion of the iron array electrode covered with concrete in deferent deeps occurred first where the concrete covered was thin.