将人行桥作为车行主桥的悬挂结构，形成一个组合式桥梁，共同解决人车通行问题，然而这种结构形式在主桥车辆荷载激励下人行桥的振动舒适性还有待研究。首先推导了悬挂式人行桥的基频估算公式并通过有限元计算进行了验证，研究表明悬挂式人行桥的基频很大程度上取决于车行主桥的自振特性。采用分离迭代法对某悬挂式人行桥的车致振动响应进行了分析，结果表明车行桥路面粗糙度、车速、车流密度等都会显著影响车辆通过时桥梁的振动响应，车致振动引起的人行桥跨中竖向峰值加速度可达到仅人行激励引起的相应值的一半以上，悬挂式人行桥行人舒适性评价中应考虑会降低其舒适度的车致振动效应的影响。%A pedestrian bridge suspended to a vehicular bridge to form a combined bridge,can provide passages not only for vehicles but pedestrians.However,the vibration comfort of the suspended pedestrian bridge under vehicle excitation from the vehicular bridge still needs to be discovered.Fundamental frequency estimation formulas for the suspended pedestrian bridge were proposed and verified through finite element method.The results show that fundamental frequencies of the suspended pedestrian bridge depend largely on dynamic characteristics of the vehicular bridge.The vehicle induced vibration of a long-span suspended pedestrian bridge was analyzed by using separated iteration methods. The results show that the vibration responses become larger with worse road condition or higher density traffic flow.The vibration responses have no evident relationship with vehicle speed.The vertical acceleration peak of the pedestrian bridge in mid-span under vehicle excitation exceeds half of that excited by pedestrians.Therefore,the vehicle induced vibration effect should be considered in the comfort evaluation of pedestrian bridges suspended to vehicular bridges.
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