南海明珠大桥混凝土结构耐久性策略

Durability strategy for concrete structures of Nanhaimingzhu Bridge

南海明珠大桥地处亚热带及热带边缘海区,具有高温、高湿、高盐、高日照、风浪大等特点,严重影响混凝土结构耐久性。分析认为,炎热海洋环境下的氯离子侵蚀是影响南海明珠大桥耐久性的首要因素。针对该问题,在环境作用等级及耐久性保障措施分析基础上,综合考虑结构部位、经济成本、技术可行性、安全要求、施工、维护管理、服役寿命等因素,提出高性能混凝土+附加防腐措施的耐久性策略。从原材料选择、配合比设计、施工控制、质量控制、耐久性维护等多角度保证措施,确保实现混凝土结构耐久性目标。

The Nanhaimingzhu Bridge is in the edge of tropical and subtropical ocean regions,which has characteristics such as high temperature,high humidity,high salinity,high sunshine hours,heavy wave,etc.That seriously affects the durability of concrete structures.The analysis result indicates that chloride penetration in the hot marine environment is the leading cause of the durability deterioration for Nanhaimingzhu Bridge.Aiming at this problem,based on the analysis on environmental action grade and durability assurance measures,considering the structural location,economic cost,technical feasibility,safety requirements,construction,maintenance management and service life,etc.,we put forward the durability strategy of high performance concrete and additional anticorrosion measures.From the selection of raw materials,mix design,construction control,quality control,durability maintenance,etc.to ensure the realization of concrete structure durability target.