飞鸟式钢管混凝土拱桥自振特性的模态分析

Modal Analysis of Self-Viberation Characteristics of Fly-bird-type CFST Arch Bridges

采用大型通用有限元程序对一座在建的三跨连续自锚(飞鸟式)钢管混凝土系杆拱桥建立了空间力学计算模型,采用模态分析方法对桥跨结构的自振特性进行了分析,计算了桥梁前16阶的自振频率,得出了该桥成桥后振动形态的基本特征。通过参数对比分析,得出了矢跨比及拱肋刚度对拱桥自振性能的影响规律。

The general finite element analysis software ANSYS was adopted to set up a three-dimen- sional finite element model of a concrete-filled steel tubular （CFST） tied arch bridge. The self-vibra- tion modes and vibration frequencies of the bridge＇s anterior 16 steps were calculated to analyze its mo- dal characteristics. Main design parameters such as ratio of rise to span and stiffness of the arch ribs have different influence on the bridge structural self-vibration characteristics. The calculating results can offer related technical parameters for the bridge＇s optimization design, construction, health moni- toring and maintenance.