考虑随机风载及交通荷载共同作用下斜拉索疲劳损伤分析  

Fatigue damage analysis of cable under random wind loads and traffic loads

作　　者：郭薇薇[1] 张雅婧 娄亚烽 GUO Weiwei;ZHANG Yajing;LOU Yafeng(School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]北京交通大学土木建筑工程学院,北京100044

出　　处：《北京交通大学学报》2023年第3期19-25,共7页JOURNAL OF BEIJING JIAOTONG UNIVERSITY

基　　金：国家自然科学基金(51878036)。

摘　　要：针对斜拉索在风和交通荷载作用下易发生振动及疲劳的问题,通过改变风参数和车辆参数,对不同组合工况下拉索应力及疲劳损伤进行分析.基于当地的气象资料和交通量统计资料,对风速、风攻角、汽车车型、车重、车流量、车间距等随机参数进行模拟,依次建立桥址处的随机风荷载模型、桥面随机汽车车流模型及移动列车荷载模型,运用Ansys软件编程实现损伤分析,最后对某大跨度公铁两用斜拉桥进行实例验证.研究结果表明:风载作用下最不利的拉索位置随着风攻角变化而变化,在风攻角不超过-6°~+6°时,短索较为不利,而超出该范围时中长索较为不利;交通车辆荷载对拉索的疲劳损伤影响较为显著,同时考虑随机风载、密集车流和移动列车工况时,拉索的等效应力幅值较仅考虑风荷载作用时增大约311.7%.To address the susceptibility of stayed cables to vibrations and fatigue caused by wind and traf⁃fic loads,this study analyzes the stress and fatigue damage of cable under different combined working conditions by varying wind and vehicle parameters.On the basis of local meteorological data and traffic statistics,the random parameters such as weed speed,wind attack angle,automobile type,weight,flow and spacing are simulated for the calculation.The study establishes a random wind load model at the bridge site,a random road traffic flow model on the bridge deck,and a moving train model to calcu⁃late fatigue damage,using Ansys software programming to conduct damage analysis.Finally,verifica⁃tion is conducted using a long-span rail-cum-road cable-stayed bridge.The research results show that the position of the most vulnerable cable under wind loads changes with the wind attack angle.Within the attack angle range of−6°to 6°,the shortest cable is the most vulnerable,while beyond this range,the medium-length cable is most at risk.Traffic load significantly influences cable fatigue damage.When considering random wind load,dense traffic flow,and the moving train condition,the equivalent stress amplitude of the cable increases by 311.7%compared to considering wind load only.

关 键 词：斜拉索 疲劳损伤 随机风荷载 随机车流 移动列车 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]