车辆荷载作用下部分斜拉桥拉索疲劳可靠度研究  

Research on Fatigue Reliability of Cables of Paritally Cable-stayed Bridge under Vehicle Load

作　　者：杨美良[1] 李波[1] 张建仁[1] 

机构地区：[1]长沙理工大学桥梁与结构工程学院,湖南长沙410076

出　　处：《公路交通科技》2007年第12期66-68,103,共4页Journal of Highway and Transportation Research and Development

基　　金：交通部西部交通建设科技资助项目(2004ZB07);湖南省交通科技创新资助项目(200410)

摘　　要：鉴于我国《公路斜拉桥设计规范》未对部分斜拉桥拉索的允许应力值作具体规定,因此,为定量地研究车辆荷载作用下部分斜拉桥拉索的疲劳可靠度,在分析斜拉索应力时程的基础上,依据等效疲劳损伤原理,对车辆荷载作用下部分斜拉桥拉索疲劳可靠度进行了研究。通过假定结构疲劳寿命服从威布尔分布,推导出了疲劳可靠度公式和疲劳可靠指标β值,得到了运营车辆组成的模型车辆荷载频值谱,并以某部分斜拉桥为实例进行了验证。结果表明,部分斜拉桥设计中,拉索强度允许应力值是合理的,不会对拉索产生疲劳破坏,因此,可供其他桥梁疲劳设计或疲劳损伤验算时参考。The tolerated stress of static strength has not been provided in domestic code for design of highway cable-stayed bridges. In order to quantify the fatigue reliability of stay cable on partially cable-stayed bridge under the influence of vehicle load, based on the accurate analysis for the time history of stay cable, fatigue reliability of the cables of partially cable-stayed bridge under vehicle load is researched according to the principle of equivalent fatigue damage. By assuming that the fatigue life is in accordance with the Weibull distribution, fatigue reliability formula and reliability target （β） of stay cable are derived and the model-vehicle load frequency value spectrum composed of daily transport vehicles is also obtained. Numerical example of the partially cable-stayed bridge is presented to testify this method. The results show that the tolerated stress of static strength is rational in the cable design of partially cable-stayed bridges and fatigue damage of cables cannot be produced. The result is referable to similar design.

关 键 词：桥梁工程 部分斜拉桥 蒙特卡罗法 疲劳可靠度 车辆荷载谱 斜拉索 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]