摘要: |
为了评估阻锈剂对再生混凝土中钢筋的保护作用,设计了钢筋再生混凝土恒电流通电加速锈蚀试验,对再生混凝土中钢筋进行电化学试验,分析钢筋极化曲线及交流阻抗,计算钢筋腐蚀电流密度,并以腐蚀电流密度作为损伤变量,运用Weibull分布函数建立再生混凝土中钢筋的可靠度函数.钢筋通电加速试验后,对钢筋进行微观形貌观测.结果表明:随着通电时间的增加,未掺阻锈剂的再生混凝土试件中钢筋表面出现颗粒状的锈蚀物;掺加阻锈剂的再生混凝土试件中钢筋表面出现大量的微裂纹;可靠度为60%时未掺和掺加阻锈剂试件中钢筋失效时间分别为880、2 060 h,阻锈剂可以使再生混凝土使用寿命延长至原来的2.34倍. |
关键词: 阻锈剂 通电加速锈蚀 极化曲线 交流阻抗 可靠度 |
DOI:10.3969/j.issn.1007-9629.2021.05.026 |
分类号:TU528.571 |
基金项目:国家自然科学基金资助项目(51468039,51868044) |
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Reliability Evaluation of Steel Bars in Recycled Concrete Based on Corrosion by Electric Current |
CHEN Kefan1,2, QIAO Hongxia1, WANG Penghui1, PENG Kuan1, ZHU Xiangchen1
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1.School of Civil Engineering, Lanzhou University of Technology, Lanzhou 730050, China;2.Chongqing Zonjo Reclaimed Resources Development Co.,Ltd., Chongqing 401122, China
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Abstract: |
In order to evaluate the protective effect of corrosion inhibitor on steel bars in recycled concrete, the constant current electrification accelerated corrosion test of reinforced recycled concrete was designed. The electrochemical test was carried out on the steel bars in concrete. The polarization curve and AC impedance of steel bars were analyzed, and the corrosion current density was calculated,which was taken as the damage variable. The reliability function of steel bars in recycled concrete was established by using Weibull distribution. After electrochemical test, the micro-morphology of the steel bars was analyzed. The results show that with the increase of power on time, granular corrosion products appear on the surface of steel bars in recycled concrete, while a large number of micro cracks appear on the surface of steel bars in recycled concrete with corrosion inhibitor. With reliability of 60% the failure time of steel bars in relyded concrete without and with corrosion inhibitor is 880,2 060 h respectively. Corrosion inhibitor can prolong the service life of recycled concrete by 2.34 times the original. |
Key words: corrosion inhibitor electrification accelerated corrosion polarization curve AC impedance reliability |