桥墩复合基频近似算法

在瑞利法和Southwell频率合成法的基础上导出了桥墩复合振动基频的计算公式,将基频表示成各惯性元和复原元所组成子系统的频率合成。然后用有限元建模来验证该方法,并分析了不同基础约束刚度和墩顶附加质量对桥墩基频的影响。计算结果表明本文导出的公式与有限元计算结果很接近。该方法适用于各种基础类型的桥墩和高耸结构基频的估算。

Approximation to Compound Fundamental Frequency of Bridge Pier

An approach was presented to evaluate fundamental frequency of bridge piers based on the combination of Rayleigh method and Southwell method.The fundamental frequency was decomposed to the sum of frequency of each subsystem consisting of deformable component and inertia component.Then finite element analysis was used to establish models to verify the presented approach.The influence of different foundation restraints stiffness and the changed mass of pier tip on fundamental frequency was also discussed.The numerical results of two approaches were observed to be in close agreement.The presented formula is adaptable to calculate fundamental frequencies of bridge piers and all kinds of tower structures.