基于健康监测的自锚式悬索桥钢箱梁细节疲劳可靠度研究  

Study on Fatigue Reliability of Details of Steel Box Girders of a Self-anchored Suspension Bridge Based on Health Monitoring

作　　者：刘建[1,2] 桂勋[2] 李传习[2] 

机构地区：[1]中南大学,湖南长沙410075 [2]长沙理工大学,湖南长沙410114

出　　处：《公路交通科技》2015年第1期69-75,共7页Journal of Highway and Transportation Research and Development

基　　金：国家自然科学基金项目(51078041)

摘　　要：为了研究大跨度自锚式悬索桥的钢箱梁构造细节在随机荷载作用下的疲劳可靠度,以国内最大跨度的独塔自锚式悬索桥平胜大桥为工程背景,在健康监测应力数据的基础上,采用疲劳可靠度理论对其钢箱梁桥面板构造细节疲劳性能进行了研究。首先基于Palmegren-Miner线性累积损伤准则建立了疲劳可靠度的极限状态方程,其次基于平胜大桥健康监测的典型应力和温度数据建立了疲劳应力谱,最后分析了不同交通量增长系数下平胜大桥钢箱梁细节疲劳可靠度。研究结果表明:平胜大桥钢箱梁的应力数据具有低应力和高循环的特点,可基于Erucode规范和等效损伤得出等效应力幅值;平胜大桥钢箱梁细节疲劳可靠指标为5.274;当交通量增长系数分别为0、0.1和0.2时,平胜大桥钢箱梁细节疲劳可靠指标在100 a后分别下降为2.305、1.681和1.395;交通量增长系数在前期对疲劳可靠指标的影响较小,而后期对疲劳可靠指标的影响较大。In order to study the fatigue reliability of details of steel girders of long-span self-anchored suspension bridges under random loads, taking Pingsheng bridge, the longest self-anchored suspension bridge with single pylon as engineering background, the fatigue performance of the deck slab of the steel box girder bridge is studied using fatigue reliability theory and health monitoring stress data. The limit state equations of fatigue reliability are established according to the Palegren-Miner linear cumulative damage rule. The fatigue stress spectra are worked out based on the typical health monitoring data of stress and temperature, and the fatigue reliability of details of the steel box girders of Pingsheng bridge in different traffic volume growth factors are analysed. Theresult shows that （ 1 ） the stress data of the steel box girders of Pingsheng bridge prossesses a low stress and high cycle peculiarity, the equal stress amplitudes can be calculated by Erucode and equal damage rule; （2） the fatigue reliability indicator of the details of steel box girder of Pingsheng bridge is 5.274 ; （3） if the growth factor of traffic volume is taken as 0, 0. 1 and 0. 2, the fatigue reliability indicator of the structure will be reduced to 2. 305, 1. 861 and 1. 395 respectively after 100 years. The growth factor of traffic volume has a low impact on the fatigue reliability in the early years, but on the contrary in later years.

关 键 词：桥梁工程 钢箱梁 疲劳可靠度 健康监测 自锚式悬索桥 

分 类 号：U446[建筑科学—桥梁与隧道工程]