3塔悬索桥动力特征参数分析

Analysis on Parameters of Dynamic Property of Triple-pylon Suspension Bridge

基于Abaqus平台建立了泰州3塔悬索桥三维有限元计算模型,采用Lanczos特征值求解方法分析了该桥的动力特征,研究了加劲梁竖向、横向和扭转刚度以及塔梁间设置弹性约束对大跨度3塔悬索桥动力特性的影响。研究结果表明,加劲梁竖向刚度、横向刚度、扭转刚度的变化均对相应方向上的振动频率有影响,对其他方向上振动频率影响甚小;中塔梁间的弹性拉索刚度仅影响竖向振动频率,当其刚度超过设计刚度后影响甚小;不设置弹性约束时,结构会出现纵飘振型;塔梁间的弹性约束对动力特性的影响大于缆梁间中央扣对动力特性的影响。

A 3D finite element model for Taizhou triple-pylon suspension bridge was established by using Abaqus software.The dynamic property of the bridge was analyzed with Lanczos matrix solver.The effects of vertical,lateral and torsion stiffnesses of stiffening girders as well as the elastic restraints between mid-pylon and stiffening girders on the dynamic property of the long-span triple-pylon suspension bridge were studied.The results show that（1） variation of vertical,lateral and torsion stiffness of stiffening girders have effects on the vibration frequency in corresponding directions only and have little effects in other directions;（2） the stiffness of the elastic cables between mid-pylon and stiffening girders have effect on the vertical vibration frequency only and the influence diminishes quickly when the stiffness exceeds the value designed;（3） the longitudinal floating vibration mode occurs while there has no elastic restrain between mid-pylon and stiffening girders;（4） the elastic restrains between mid-pylon and stiffening girders have more effect on the dynamic property of the bridge than the central buckle does.