用电流阶跃法在时域与频域中研究钢筋锈蚀  

Galvanostatic Pulse Method in Time Domain and Frequency Domain to Determine the Corrosion Status of Rebar in Concrete

作　　者：阎培渝[1] 崔路[1] 

机构地区：[1]清华大学土木工程系,北京100084

出　　处：《建筑材料学报》1999年第3期199-205,共7页Journal of Building Materials

基　　金：国家基础性研究重大项目

摘　　要：利用电流阶跃法测量位于模拟混凝土孔溶液中和混凝土中的钢筋锈蚀状态．提出了新的时域和频域分析方法，并对测量结果进行了分析，由此可以较准确地确定混凝土内钢筋的极化电阻Ｒｐ 和钢筋表面不均匀系数α，从而可以确定钢筋的锈蚀速率和点蚀危险性；还可以通过所得阻抗谱了解钢筋的锈蚀机理．研究发现，当钢筋严重锈蚀时，腐蚀电流和钢筋表面不均匀系数均能反映钢筋锈蚀状态，但当钢筋处于脱钝临界状态时，腐蚀电流和钢筋表面不均匀系数反映的信息常有矛盾之处，腐蚀电流判据难于准确判断钢筋锈蚀状态，而钢筋表面不均匀系数判据则不存在这个问题．The corrosion status of rebar in concrete and simulated pore solution was evaluated by using galvanostatic pulse method. A new algorithm was developed to analyze the measuring results in time domain and frequency domain. The polarization resistance R p and surface dispersion factor α of rebar in concrete can be determined. Therefore the corrosion rate and the risk of pit corrosion of rebar can be diagnosed. The corrosion mechanism was studied with the acquired impedance spectrum. It was found that both the corrosion current and α can be used to describe the corrosion status when rebar corrodes badly; but there is frequently discrepancy between the results from corrosion current and α in the critical period of depassivation. It is difficult to use the criterion of corrosion current to judge the corrosion status of rebar in very initial stage of depassivation. Otherwise it can be done to use α criterion.

关 键 词：电流阶跃法 钢筋 锈蚀 阻抗谱 钢筋混凝土 

分 类 号：TU528.571[建筑科学—建筑技术科学]