沿海某混凝土框架结构钢筋锈蚀原因分析与修复加固对策

Research on reinforced bar rust and repairing and strengthening measures to RC frame near the sea

针对某地下混凝土框架结构钢筋发生严重锈蚀的现象,基于钢筋锈蚀的机理及其基本条件,从混凝土碳化、氯离子含量、设计与施工及建筑工作环境等不同方面进行理论研究和检测分析,最终找出钢筋锈蚀的主要原因和影响因素,验证了"碳化深度"计算式的适用性,并根据实测数据对"部分碳化区长度"的数学模型在高湿环境下的应用进行了修正。最后提出去除盐雾侵蚀混凝土面层、涂刷阻锈剂、恢复混凝土保护层厚度的办法满足钢筋强碱性环境的耐久性要求,利用粘贴碳纤维补强的办法进行结构承载力修复,以期为沿海地区混凝土结构耐久性设计与施工提供参考。

According to the theoretical and detective analysis, the influence factors, such as concrete carbonation, the chloride ion content, the design and construction measures, which can cause the rust of the bar, were analyzed respectively. The main reasons were found out, and the calculation formula for the carbonation length was also proved. Based on the data obtained in work site, the formula for the half carbonation length was modified when it is used in high humidity environment. The rusted concrete protect layer was eliminated; the anti-rust reagent was brushed when the rust bar was cleared by the special machine which can match the need of the durability. The carbonic fiber reinforcement polymer were stuck on the new concrete protect layer which can provided the bearing capacity. The measures can be good reference for the same project.