【摘要】 采用有限元分析和动力测试的方法,以矮寨大桥为对象,研究了中央扣对其模态特性的影响。有限元分析结果表明:中央扣能够显著提高桥梁的纵飘频率;中央扣对反对称侧弯频率的影响比正对称大;刚性中央扣对主缆正对称振型频率提升很大,而柔性中央扣对此几乎没有影响。矮寨大桥气弹模型动力测试研究发现:反对称侧弯频率随中央扣刚度的增大而增加;中央扣对竖向振动的模态频率影响较小;中央扣能够提高悬索桥的整体刚度,相应频率均有不同程度的提高,其中以反对称扭转和纵向振动频率提升最为显著。更多还原

【Abstract】 Finite element analysis( FEA) and dynamic test are employed to investigate the influence of central buckles on the modal characteristics of Aizhai bridge. The FEA result shows that(1) central buckles can significantly raise the longitudinal floating frequency of the bridge;(2) the influence of central buckles on anti-symmetrical lateral bending frequencies is larger than those on symmetrical mode;(3) rigid central buckles can raise the symmetric vibration modal frequencies of main cables,while flexible central buckles almost have no impact on it. Further test on the dynamic behavior of the aeroelastic model of Aizhai bridge is carried out. The result indicates that(1) the anti-symmetric lateral bending modal frequencies increase with the increase of central buckles’ stiffness;( 2) central buckles have little influence on the vertical modal frequencies;(3) central buckles can enhance the whole stiffness of the bridge and natural frequencies of the suspension bridge,especially for the anti-symmetric torsional and longitudinal vibration frequencies.更多还原