锈蚀RC梁斜截面受剪抗力退化概率模型  

Probabilistic model of shear resistance degradation for corroded reinforced concrete beam

作　　者：王磊[1] 丁蔚[1] 马亚飞[1] 张建仁[1] 

机构地区：[1]长沙理工大学桥梁工程安全控制省部共建教育部重点实验室,湖南长沙410004

出　　处：《长沙理工大学学报（自然科学版）》2011年第4期34-41,共8页Journal of Changsha University of Science and Technology:Natural Science

基　　金：国家自然科学基金资助项目(50878031);湖南省优秀研究生创新项目(CX2011B355)

摘　　要：针对氯盐环境下混凝土桥梁中钢筋锈蚀引起构件抗剪承载力退化问题,考虑混凝土、箍筋和斜筋对RC梁抗剪承载力的贡献,结合钢筋锈蚀的时变效应,基于Monte Carlo数值模拟方法,建立了RC梁抗剪承载力退化概率模型,对比了基于不同规范建立的受剪抗力退化概率模型的异同,分析了受剪抗力退化对保护层厚度、氯离子浓度等的敏感性.研究结果表明,采用不同规范公式对结构抗力退化概率分析结果影响不大;不同参数对抗剪退化的影响作用和影响程度差别很大;对于端部未作箍筋加密构件而言,构件受剪抗力退化对斜筋锈蚀比箍筋锈蚀更为敏感.The probabilistic model of shear resistance degradation for corroded RC beam is developed based on Mont Carlo numerical simulation.The deterioration of shear capacity is analyzed for corroded RC beam in chloride ion environment.In this model,the contributions of concrete,stirrups and diagonal reinforcements are considered,and the time-variant effect of corrosion of steel rebar is incorporated.A comparison between shear models based on the Chinese and American Codes is conducted.The sensitivity of concrete cover and chloride ion concentration is analyzed.The results show that the effect of computational models from various specifications on shear resistance is not obvious,and the influencing difference of various factors on shear degradation is significant.For the member with the same stirrups at ends and midspan,the effect of corrosion of diagonal reinforcements on shear degradation is more sensitive than that of stirrups.

关 键 词：RC桥梁 锈蚀 斜筋 抗剪退化 概率模型 

分 类 号：U444[建筑科学—桥梁与隧道工程] TU375.1[交通运输工程—道路与铁道工程]