氯盐环境下大型混凝土桥梁构件耐久性可靠度分析

Reliability Analysis of Durability for Large-scale Concrete Bridge Components in Chloride Environment

为保障工程结构耐久性,先需对构件退化过程进行分析与评价。对于氯盐环境中的大型混凝土构件,其几何外形较为复杂,采用二维氯离子扩散分析方法才能得到更为合理的结果;同时采用可靠度法方法进行评价,以充分考虑分析中涉及的不确定性因素。建立氯盐环境下大型混凝土桥梁构件耐久性可靠度分析框架,以Fick第二定律描述氯离子扩散过程,并通过有限元方法进行求解,在此基础上采用响应面方法进行可靠度分析。通过MATLAB编制了相关程序,并进行了实例计算,为大跨度桥梁的退化分析、运营管理、寿命预测等工作提供借鉴。

Analysis and assessment of the deterioration process is the start point of durability maintenance for any engineering structures. For large-scale concrete components in chloride environment,to obtain ratio section shape. consideration. large-scale con nal results, 2D chloride diffusion analysis should be performed to simulate the complex Meanwhile reliability based assessment need to be adopted to take uncertainties into Analytical framework is established in this research to analyze the durability reliability of crete structure components in chloride environment. Firstly, 2D Fick＇s second law of diffusion is used to describe the diffusion process of chloride ions. Then the control equation is solved by finite element method. Finally, response surface method is adopted to find out the reliability level. Aforementioned theoretical framework is programmed by example is performed. The methodology established deterioration analysis, management and life anticipation of large-span bridges.