采用自行设计制造的人工模拟气候大型试验箱, 研究钢筋混凝土结构在模拟海洋环境中的腐蚀情况。采用自腐蚀电位、线性极化以及电化学阻抗谱等方法综合研究了标准养护14天的普通硅酸盐混凝土试样置于试验箱中钢筋腐蚀的临界状态判断标准。结果表明, 当混凝土中钢筋表面的氯离子浓度达到诱导钢筋腐蚀的临界浓度时, 自腐蚀电流密度会有数量级的突增, 线性极化法和电化学阻抗谱法均能用来准确判断这一临界腐蚀状态。

An artificial climate experiment system was designed and established to study the reinforcement corrosion of concrete structures exposed to simulated marine environment. Electrochemical methods such as corrosion potential, linear polarization and electrochemical impedance spectroscopy were applied to study the reinforced steel bar corrosion threshold of ordinary portland concrete (OPC). The concrete specimens were cured for 14 days in a standard cure environment before placed in the artificial climate cabinet. The results show that the corrosion current density of reinforcing bar increases rapidly in a order of magnitude when the surface chloride concentration near the steel bar reaches the chloride threshold value for reinforcement corrosion. Both linear polarization and electrochemical impedance spectroscopy can be used to determine the corrosion threshold accurately.