大跨度连续钢桁柔性拱桥自振特性分析

Analysis on self-vibration properties of large-span continuous-steel-truss flexible arch bridge

采用MIDAS Civil有限元软件,建立了银川机场黄河特大桥的梁单元模型,并对全桥进行了动力特性分析,结果表明,银川机场黄河特大桥前12阶振型的频率在2.5 Hz以内,基频为0.249 122 Hz,振动频率较低,模态密集,结构整体刚度较大;该桥横向弯曲振动最早出现,横向刚度对该结构的设计起控制作用。

The thesis applies MIDAS Civil finite element software,establishes Yellow River Bridge beam element model of Yinchuan airport,and carries out dynamic property analysis of the bridge. Results show that： the vibration frequency of the previous 12-stage of the Yellow River Bridge of Yinchuan airport is within 2. 5 Hz,the basis frequency is 0. 249 122 Hz,the vibration frequency is low,the modal intensity and integral structure rigidity are big,the horizontal bending vibration will early occur; the horizontal rigidity play the control role for the structure design.