海洋环境下钢筋混凝土结构耐久性评估

Durability assessment of reinforced concrete structures in marine environment

钢筋锈蚀是海洋环境下混凝土结构破坏的主要原因之一。考虑钢筋锈蚀后截面积和粘结力的损失 ,分析了海洋环境下混凝土结构的可靠度评估方法。将混凝土表面氯离子浓度、保护层厚度和扩散系数作为随机变量 ,建立了混凝土保护层中氯离子浓度分布的随机模型 ,推导出了氯离子浓度的均值 ,提出了海洋环境下混凝土结构耐久性寿命评估的方法 ,并用于某海港西大堤钢筋混凝土护栏耐久性寿命评估。

Corrosion of steel reinforcement is one of the most significant causes of deterioration of reinforced concrete structures in marine environment. It is assumed that corrosion will lead to a reduction in reinforcement cross-sectional area and a reduction in bond strength. The reliability-based approach to the assessment of reinforced concrete structures in marine environment is analyzed. Stochastic model of the chloride ion concentration at steel-concrete interfaces is established with the random variables of the chloride ion concentration at concrete surfaces, the thickness of concrete covers and the chloride diffusion coefficient. The mean value of the chloride ion concentration at steel-concrete interfaces is obtained. The approach to the durable life assessment of concrete structures in marine environment is presented, and it is used to assess the durable life of the balustrades on the harbor west dam.