机构地区: 华南理工大学材料科学与工程学院特种功能材料教育部重点实验室
出 处: 《混凝土》 2007年第1期14-18,共5页
摘 要: 研究了掺盐钢筋混凝土在不同水化龄期及经电化学除盐处理后的自腐蚀电位和腐蚀速率,并跟踪了断电后钢筋的自腐蚀电位和腐蚀速率随时间的变化。研究结果表明:经电化学除盐处理后,钢筋的自腐蚀电位负移、腐蚀电流增大。但随着时间的推移,腐蚀电位正移、腐蚀电流减小,抽芯后的试件由于其钢筋表面O2量充足,试件各个部位钢筋的自腐蚀电位在30d后就正移至-100mV以上,而未抽芯试件则需要大约60d,才能正移至-200mV以上。电化学除盐后,如果试件中各部位钢筋电位不均匀,将可能会加剧钢筋的电化学腐蚀,这是电化学除盐技术研究与应用中值得注意的一个问题。 It this study, sodium chloride doped reinforced concrete specimens were subjected to electrochemical chloride extraction after cured at humid atmosphere for 100 days and the half-cell potential (HCP) and corrosion current of steel bars in concrete electrochemical chloride extraction(ECE) were determined.The results show that at the moment when ECE treatment is removed HCP becomes more negative and corrosion current becomes larger in comparison to those before ECE treatment, then HCP shifts positively and corrosion current decreases with time. 30days after ECE treatment the HCP of cored specimens turns to about -100mV due to the existence of sufficient oxygen around the exposed steel bars,but for the recover of the HCP of un-cored specimens,longer time,about 60 days,is to be taken. The non-homogeneous HCP distribution at different layers of specimen after ECE treatment may induce secondary corrosion of steel bars. So attention to this phenomenon is needed.
关 键 词: 电化学性能 钢筋混凝土 腐蚀 电化学除盐 半电池电位 线性极化
领 域: [建筑科学]