摘要
为研究多塔悬索桥加劲梁端在车辆荷载作用下的纵向位移特征,以某三塔四跨悬索桥为工程背景建立了全桥有限元模型,并对竖向移动力作用下的梁端纵向振动响应进行了时频域分析。结果表明:作用在主跨上的移动荷载会导致所在跨梁端位移变形特征呈类似正弦形状,同时通过中塔和缆索影响另一跨的梁端响应;移动力和移动速度的大小均会影响梁端分均累计位移,前者的增加会显著放大各频率的梁端振动幅值,而后者的增加会导致振动中高频成分的增多。通过参数分析发现中塔刚度,加劲梁纵向支承体系和桥塔数量会改变多塔悬索桥的纵向刚度。纵向刚度的提高会增强梁端动态响应,导致梁端累计位移的增加;同时抑制梁端纵向拟静态响应,导致梁端累计位移的减少。
To investigate the longitudinal displacement characteristics of the stiffening girder end of a multi-tower suspension bridge under vehicular loading,a comprehensive finite element model of a specific multi-tower suspension bridge was established.Temporal and spectral analyses were conducted on the longitudinal vibrational response of the girder end under vertical moving force.The results indicate that the application of moving loads on the main span induces sinusoidal-like deformation patterns in the girder end of the corresponding span.Additionally,the responses of the girder end in one span are influenced by the mid-tower and cables,impacting the response of the opposite span.Both the magnitude of the moving force and the speed significantly affect the cumulative displacement of the girder end.The former amplifies vibrational amplitudes across various frequencies,while the latter results in an increase in high-frequency components in the vibration.Parametric analysis reveals that the stiffness of the mid-tower,the longitudinal support system of the stiffening girder,and the number of bridge towers alter the longitudinal stiffness of the multi-tower suspension bridge.Increased longitudinal stiffness enhances the dynamic response of the girder end,leading to an increase in cumulative displacement.Simultaneously,it inhibits the quasi-static response of the girder end,resulting in a decrease in cumulative displacement.
作者
王宽
李坤
申和顺
曹鸿猷
WANG Kuan;LI Kun;SHEN He-shun;CAO Hong-you(School of Civil Engineering&Architecture,Wuhan University of Technology,Wuhan 430070,China;Central&Southem China Municipal Engineering Design and Research Institute Co.Ltd,Wuhan 430070,China)
出处
《武汉理工大学学报》
CAS
2024年第8期61-68,共8页
Journal of Wuhan University of Technology
关键词
多塔悬索桥
加劲梁纵向位移
累计位移
移动力模型
纵向支承体系
multi-tower suspension bridge
longitudinal displacement of main girders
cumulativedisplacement
moving force model
longitudinal support system