随机车载激励下大跨度悬索桥中央扣振动控制研究  

Vibration control of central buckles of long-span suspension bridge under random vehicle excitation

作　　者：赵越 黄平明 付樱姿[1] 袁阳光 苏波同 ZHAO Yue;HUANG Pingming;FU Yingzi;YUAN Yangguang;SU Botong(College of Civil Engineering and Architecture,Xi’an University of Technology,Xi’an 710048,China;Shaanxi Provincial Key Lab of Highway bridge and Tunnel,Xi’an 710064,China;College of Highway,Chang’an University,Xi’an 710064,China;School of Civil Engineering,Xi’an University of Architecture and Technology,Xi’an 710054,China)

机构地区：[1]西安理工大学土木建筑工程学院,西安710048 [2]陕西省公路桥梁与隧道重点实验室,西安710064 [3]长安大学公路学院,西安710064 [4]西安建筑科技大学土木工程学院,西安710055

出　　处：《振动与冲击》2024年第13期288-298,共11页Journal of Vibration and Shock

基　　金：陕西省自然科学基础研究计划一般项目-青年项目(2022JQ-366);陕西省自然科学基础研究计划一般项目-面上项目(2023-JC-YB-321);陕西省公路桥梁与隧道重点实验室(长安大学)开放基金资助(300102212509)。

摘　　要：大跨度悬索桥车流荷载作用下振动响应明显,关键构件疲劳损坏直接影响结构服役状态及运营安全。为改善大跨度悬索桥结构振动响应,基于有限元模拟对柔性中央扣及刚性中央扣振动控制效应开展研究,分析了中央扣对结构模态特性的影响,并基于考虑参数相关性及车流参数聚类特征的随机车流模拟方法,分析了车流荷载下的中央扣振动控制效应及其对吊索钢丝寿命影响。研究结果表明:中央扣主要对悬索桥的反对称竖弯频率及一阶扭转频率存在影响,随着柔性中央扣数量的增加结构振动频率有所提升,刚性扣的提升效果与三柔性中央扣接近。车流作用下中央扣可显著减小梁端位移、梁端累计位移及缆梁相对位移,随柔性中央扣数目的增加,控制效率有所提升但提升效果逐渐减小。刚性中央扣对梁端位移及梁端累计位移的控制效果与三柔性扣索接近,其对缆梁相对位移的控制效果好于柔性中央扣。吊索钢丝的疲劳寿命与弯曲应力响应的变化趋势一致,长吊索整体弯曲应力水平相对较小,中央扣对其钢丝寿命影响不明显。短吊索钢丝疲劳寿命则大幅提升,但柔性中央扣数量的增加提升效果有限,刚性中央扣提升效果与三柔性扣索接近。Vibration response of large-span suspension bridge under traffic load is obvious,and fatigue damage of key components directly affects structural service status and operational safety.Here,to reduce vibration response of large-span suspension bridge structure,the vibration control effects of flexible and rigid central buckles were studied based on finite element simulation.Effects of central buckles on structural modal characteristics were analyzed.Based on the random traffic flow simulation method considering parametric correlation and traffic flow parameters’clustering characteristics,the control effects of central buckles under traffic flow load and their impact on the life of suspender steel wire were analyzed.The study results showed that central buckle mainly affects the antisymmetric vertical bending frequency and the first-order torsional frequency of suspension bridge,with increase in the number of flexible central buckles,bridge structural vibration frequency lifts,and the lifting effect of rigid central buckles is similar to that of three flexible central buckles;under the action of traffic flow,central buckle can significantly reduce beam end displacement,beam end cumulative displacement and cable-beam relative displacement;with increase in the number of flexible central buckles,the control efficiency lifts but the lifting effect gradually decreases;the control effect of rigid central buckles on beam end displacement and cumulative displacement is similar to that of three flexible buckles,and its control effect on cable-beam relative displacement is better than that of flexible central buckle;the fatigue life of suspender steel wire is consistent with the varying trend of bending stress response;the overall bending stress level of long suspender is relatively small,and central buckle has no obvious impact on its steel wire life;the fatigue life of short suspender steel wire lifts significantly,but increase in the number of flexible central buckles has limited lifting effect;the lifting effect of rig

关 键 词：悬索桥 中央扣 车流荷载 梁端位移 疲劳寿命 

分 类 号：U443.38[建筑科学—桥梁与隧道工程]