Variation and Impact of Hydrogen Content of Reinforcing Bars in Concrete Caused by Bidirectional Electromigration
XIE Zhenkang1,2, JIN Weiliang1, MAO Jianghong2, ZHANG Jun2, FAN Weijie2, XIA Jin1
1 Institute of Structural Engineering,Zhejiang University,Hangzhou 310058,China 2 Ningbo Institute of Technology,Zhejiang University,Ningbo 315100,China
Abstract: Bidirectional electromigration repair tests were carried out on concrete specimens under different electrification duration and current density, for the sake of digging out the effect of hydrogen evolution on steel bars in concrete during bidirectional electromigration repair process. Hydrogen permeation degree of steel bars was determined by quantitatively measurement of hydrogen content in steel bars. The mechanical properties of steel bars were studied by constant strain rate tensile test and scanning electron microscope observation on fracture. Electrochemical chloride extraction was also conducted for comparison. In light of the results, extending the electrification time and enlarging the current density would give rise to a series variations: the increase in hydrogen content of reinforcing bar in concrete, the reduction in plasticity of reinforcing bar, the size diminishing and depth decrease of fracture dimple of reinforcing bar, and the risk of hydrogen embrittlement increased. Compared with electroche-mical chloride extraction, bidirectional electromigration could effectively inhibit hydrogen penetration into steel bars and reduce the risk of hydrogen embrittlement of steel bars. Furthermore, the quantitative analysis indicated that there was a good correlation between the hydrogen content in steel bars and the plastic properties of steel bars. Specifically, every 1 μg/g increase in hydrogen content would bring about a 12.18% decrease in fracture energy ratio of steel bars and a 9.92% increase in hydrogen embrittlement sensitivity coefficient.
Jin W L, Zhao Y X. Durability of concrete structures, Science Press, China, 2014(in Chinese).金伟良, 赵羽习. 混凝土结构耐久性, 科学出版社, 20142 Liu Y, Du R G, Ling C J. Corrosion Science and Protection Technology, 2008, 20(2),125(in Chinese).刘玉, 杜荣归, 林昌健. 腐蚀科学与防护技术, 2008, 20(2),125.3 Sun W B, Gao X J, Yang Y Z, et al. Corrosion Science and Protection Technology, 2009, 21(3),308(in Chinese).孙文博, 高小建, 杨英姿, 等. 腐蚀科学与防护技术, 2009, 21(3),308.4 Jing Z W. Materials Review, 2008, 22(2), 78(in Chinese).蒋正武. 材料导报, 2008, 22(2), 78.5 Tang J W, Li S L, Cai W C, et al. The Ocean Engineering, 2008, 26(3), 87(in Chinese).唐军务, 李森林, 蔡伟成, 等. 海洋工程, 2008, 26(3), 87.6 Xu C, Jin W L, Huang N, et al. Journal of Zhejiang University(Engineering Science), 2015, 49(6), 1128(in Chinese).许晨, 金伟良, 黄楠, 等. 浙江大学学报(工学版), 2015, 49(6), 1128.7 Wang W L, Xu J X, Gao G F, et al. Journal of Hohai University(Natural Sciences), 2014, 42(6), 535(in Chinese).王卫仑, 徐金霞, 高国福, 等. 河海大学学报(自然科学版), 2014, 42(6), 535.8 Shan H Y, Xu J X, Jiang L H. Materials Review B: Research Papers, 2016, 30(7), 1(in Chinese).单鸿猷, 徐金霞, 蒋林华. 材料导报:研究篇, 2016, 30(7), 1.9 Ministry of Transport of the People's Republic of China. JTS 153-2-2012, Technical Specification for Electrochemical Corrosion Protection of Reinforced Concrete Structures in Harbour Engineering. China, 2012.中华人民共和国交通运输部. JTS 153-2-2012, 海港工程钢筋混凝土结构电化学防腐技术规范. 中国, 2012.10 Jayalakshmi S, Kim K B, Fleury E. Journal of Alloys & Compounds, 2006, 417(1-2), 195.11 Sun Y W, Chen J Z, Liu J. Acta Metallurgica Sinica, 2015, 51(11), 1315(in Chinese).孙永伟, 陈继志, 刘军. 金属学报, 2015, 51(11), 1315.12 Siegwart M, Lyness J F, McFarland B J, et al. Construction and Building Materials, 2005, 19(8), 585.13 Ueda T, Ashida M, Mizoguchi S, et al. Proceedings of the Japan Society of Civil Engineers, 2010, 35(613), 189.14 Chen J Y. Effect of electrochemical rehabilitation on stressed steel bar in concrete simulated solution. Master’s Thesis, Zhejiang University, China, 2016(in Chinese).陈佳芸. 电化学修复技术对混凝土模拟溶液中受力钢筋的作用效应. 硕士学位论文, 浙江大学, 2016.15 Li T. Experimental study on hydrogen embrittlement evaluation and control of reinforced concrete structures under electrochemical remediation. Master’s Thesis, Zhejiang University, China, 2017(in Chinese).李腾. 电化学修复中混凝土结构中受力钢筋氢脆评估与控制试验研究. 硕士学位论文, 浙江大学, 2017.16 Xu C, Jin W L, Zhang S Y. Jouenal of Building Materials, 2014, 17(4), 572(in Chinese).许晨, 金伟良, 章思颖. 建筑材料学报, 2014, 17(4), 572.17 Xu C, Jin W L, Zhang S Y. Journal of Building Materials, 2014,17(5), 761(in Chinese).许晨, 金伟良, 章思颖. 建筑材料学报, 2014, 17(5), 761.18 Jin W L, Huang N, Xu C, et al. Journal of Zhejiang University(Engineering Science), 2014, 48(9), 1586(in Chinese).金伟良, 黄楠, 许晨, 等. 浙江大学学报(工学版), 2014, 48(9), 1586.19 Mao J H, Jin W L, Zhang H, et al. Journal of Chinese Society for Corrosion and Protection, 2015, 35(6), 563(in Chinese).毛江鸿, 金伟良, 张华, 等. 中国腐蚀与防护学报, 2015, 35(6), 563.20 Zhu Y F, Mao J H, Jin W L, et al. Building Structure, 2018(2), 14(in Chinese).朱垚锋, 毛江鸿, 金伟良, 等. 建筑结构, 2018(2), 14.21 Zhang Y, Zhang J X, Wang K. Material Protection, 2009, 42(8), 51(in Chinese).张羽, 张俊喜, 王昆, 等. 材料保护, 2009, 42(8),51.22 Stahle R W. In: International Conference on Stress Corrosion Cracking and Hydrogen Embrittlement of Iron Base Alloys. France, 1973, DOI:10.1149/1.2129122.23 Chu W Y, Li S Q, Xiao J M, et al. Journal of University of Science and Technology Beijing, 1979, 16(1), 179(in Chinese).褚武扬, 李世琼, 肖纪美, 等. 北京科技大学学报, 1979, 16(1), 179.24 Chu W Y, Hsiao C M, Li S Q. Engineering Fracture Mechanics, 1982, 16(1), 115.25 Chu W Y, Wang H L, Ma R T, et al. Acta Metallurgica Sinica, 1985, 21(1), 86(in Chinese).褚武扬, 王核力, 马若涛, 等. 金属学报, 1985, 21(1), 86.26 General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China/China National Standardization Ma-nagement Committee. GB/T 223.82-2007, Steel-determination of hydrogen content-Inert gas pulse melting thermal conductivity method. China, 2007.中国人民共和国国家质量监督检验检疫总局/中国国家标准化管理委员会. GB/T 223.82-2007, 钢铁氢含量的测定 惰气脉冲熔融热导法. 中国, 2007.27 Zhang S H, Wang R, Luo S J. Corrosion & Protection, 2009, 30(3), 172(in Chinese).张士欢, 王荣, 雒设计. 腐蚀与防护, 2009, 30(3), 172.28 Zeng X G, Liu K, Luo H, et al. Hot Working Technology, 2015(6),41(in Chinese).曾宪光, 刘康, 罗宏, 等. 热加工工艺, 2015(6), 41.29 Yang Y J, Li Z T, Pang X L, et al. Corrosion & Protection, 2009, 30(11), 787(in Chinese).杨勇进, 李宗田, 庞晓露, 等. 腐蚀与防护, 2009, 30(11), 787.30 Billingham M, John G. In: CORROSION 2008. NACE International, 2008.