中文摘要：

针对目前氯盐侵蚀钢筋混凝土桥梁耐久性研究的不足,将双向电渗技术应用于受氯盐侵蚀的桥梁,实现了水位变化区承台的混凝土耐久性提升,提出了依据设计资料和现场数据检测获取氯离子扩散系数和表面氯离子浓度等关键参数,并用Fick第二定律数值解进行双向电渗后寿命预测。研究成果表明：双向电渗技术适用于水位变动区混凝土的耐久性提升,推迟依托工程的耐久性失效预警期达10年,可为大量氯盐侵蚀环境下的钢筋混凝土桥梁的耐久性提升提供一种有效手段。

英文摘要：

Aimed at the insufficient study on durability of reinforced concrete bridge under chloride attack,bidirectional electro-migration rehabilitation（BIEM）was applied to the bridges subject to chloride attack to improve the durability of concrete bearing platform in the water level varying areas.In accordance with the design data and measured data,certain parameters,including chloride diffusivity and surface chloride concentration,were obtained.Additionally,life prediction after bidirectional electro-migration rehabilitation could be realized by using the numerical solution of Fick＇s second law.The results show that BIEM is suitable for improving the concrete durability in water level varying areas.With the achievement of extending the service life of engineering applicants for ten years,BIEM can be an effective method to improve the durability of existed reinforced concrete bridges under chloride attack.