考虑不同失效模式的钢筋混凝土梁时变可靠度分析  

Time-dependent reliability analysis of reinforced concrete beam under different failure modes

作　　者：张建仁[1] 鲍勇军[1] 王磊[1] 彭建新[1] 马亚飞[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：《交通科学与工程》2011年第4期18-23,30,共7页Journal of Transport Science and Engineering

基　　金：国家自然科学基金资助项目(50878031);湖南省研究生科研创新项目(CX2011B355)

摘　　要：考虑钢筋混凝土梁受弯和受剪破坏两种主要失效模式,对比分析了钢筋锈蚀影响下主梁两种失效模式的时变可靠指标变化,探讨了不同失效模式相关系数的变化规律,进而采用Ditlevsen窄界限理论计算了主梁构件时变可靠指标.分析结果表明:在钢筋混凝土梁轻微锈蚀情况下,以抗弯失效为主;而在深度锈蚀情况下,以抗剪失效为主.在锈蚀影响下,主梁受弯和受剪失效模式的相关性很小,对其时变可靠度影响也不大.在失效模式低相关情况下,基于Ditlevsen窄界限理论,其失效概率上、下限差异很小.The two main failure modes of flexural and shear failure for the corroded reinforced concrete beams are considered.The Monte Carlo method is used to evaluate the time-dependent reliability index due to chloride-induced corrosion under different failure modes.The correlation coefficient of different failure modes is discussed.The time-dependent reliability index of the girder is calculated based on the theory of Ditevsen.The results show that the flexural failure is the main failure under the slight corrosion,while the shear failure is dominated under severe corrosion;the time-dependent reliability index changed very little for the correlation of flexural and shear failure mode is small.Based on the theory of Ditevsen,the boundary between lower and upper limit is very small under the low correlation of failure modes.

关 键 词：桥梁工程 受弯构件 钢筋锈蚀 时变可靠度 失效模式 相关性 

分 类 号：U445.73[建筑科学—桥梁与隧道工程]