摘要
基于70 m整孔预制箱梁的结构、材料及海域环境特点,结合现场箱梁结构保护层厚度、氯离子初始浓度以及氯离子扩散系数等的实际检验检测结果,对混凝土保护层厚度、氯离子初始浓度、氯离子扩散系数、氯离子临界浓度以及结构表面氯离子浓度等各类耐久性影响因素的不确定性进行概率统计分析,确定其统计分布特征。通过MonteCarlo随机模拟,得出了70 m箱梁结构使用寿命的近似概率密度分布,通过假设检验,确定其服从对数正态分布,并给出在不同保证率情况下箱梁结构设计使用寿命的取值。
Based on box girder structure the characteristics of Hangzhou Bay of structural design, material, corrosiveness of service environment of 70 m Bridge and the site detection results of concrete cover thickness, initial concentration and diffusion coefficient of chloride ions, the stochastic characters of durability influencing factors such as concrete cover thickness, initial concentration and critical concentration of chloride ions, chloride ions diffusion coefficient in concrete, and structural surface concentration of chloride ions were analysed and the statistical distribution characteristics were determined. Through Monte Carlo stochastic simulation, the approximate probability density distribution of service life of 70 m PC box girder was obtained. The log-normal distribution character of the structure was determined by hypothesis testing. The values of designed service life of box girder under different reliability index were given.
出处
《公路交通科技》
CAS
CSCD
北大核心
2009年第9期59-63,69,共6页
Journal of Highway and Transportation Research and Development
基金
国家自然科学基金资助项目(50808005)
国家科技支撑计划资助项目(2006BAJ27B04)
北京市科技计划课题资助项目(Y060506000007022)
关键词
桥梁工程
服役寿命
随机分析
结构耐久性
bridge engineering
service life
stochastic analysis
structural durability
