对连接2栋建筑净跨度达45 m的某曲线型钢桁架人行天桥展开现场人行振动加速度响应实测,得到了在各种行走和跳跃工况下人行天桥加速度响应的现场实测数据。基于希尔伯特-黄变换,对人行天桥结构的动力特性,包括自振频率和结构阻尼,进行了有效识别。利用有限元软件建立了该人行天桥结构有限元模型,分析天桥结构在行人荷载激励条件下的动力响应。对实测数据和数值分析结果进行比对,数值分析结果基本符合现场实测数据。最后,结合国内外规范对该天桥的人行舒适度进行了合理评价。
We carried out a field measurement on the pedestrian-induced vibration of a steel truss footbridge connecting two buildings with a curved planar shape and a net span up to 45 m. Based on the Hilbert-Huang transformation, we effectively identified the dynamic properties of the footbridge, i. e. , natural frequencies and damping ratios. We established the finite element mode of the footbridge. The finite element analysis results agree well with those of the field measurements. We also accessed the vibration serviceability of the footbridge using the domestic and international standards currently available.