杭州湾跨海大桥混凝土结构耐久性解决方案

Strategies to ensure durability of concrete structure for Hangzhou Bay Bridge

为了确保杭州湾跨海大桥混凝土工程达到100年设计使用年限,根据特殊腐蚀环境进行相应的混凝土结构耐久性研究和设计。结合当前现有研究成果,对海洋环境下钢筋混凝土结构的腐蚀破化特征和防护技术进行介绍。针对本工程混凝土结构的不同部位,提出混凝土结构耐久性多层次综合方案体系、海工耐久混凝土设计原则、耐久性关键指标与评估试验方法、施工及质量验收标准、混凝土结构基本防腐蚀措施和附加防腐蚀措施及其基于耐久性的相互协同解决方案,并通过建立耐久性无损监测系统和暴露试验站对混凝土结构的预期寿命进行预测评估。分析结果表明,对混凝土结构的特定腐蚀环境,提出耐久性解决方案是经济可行的。本研究对同类跨海大桥的耐久性设计与施工具有一定的参考价值。

In order to ensure the design service life of 100 years for the Hangzhou Bay Bridge, taking into consideration of the special corrosive environment, study and design on durability of concrete structure are conducted. The latest relevant research results are introduced, and the corrosion characteristics-of and protection techniques for marine reinforced concrete structures are discussed. Considering various parts of reinforced concrete structure of the project, a multilevel comprehensive plan for the overall durability of reinforced concrete structures is These include design principles for the mix of marine durable concrete, durability indices and the corresponding evaluation method, standard for construction and quality acceptance, basic protective measures and additional protective measures for concrete structure, and durability-based solutions for synchronous cooperation. Moreover, the expected service life of concrete structure is assessed through establishing a non-destructive permanent monitoring system of a corrosion risk and exposure testing station. Based on the analysis, strategies to ensure durability of the concrete structure are economical and feasible under the corrosive environment. The results of the present study may serve as a reference for durability design and construction of similar cross-sea bridges.