关于桥梁结构地震响应振型贡献的讨论

Discussion on Seismic Response Modal Contribution of Bridge Structures

通常桥梁结构地震响应的贡献主要来自于低阶振型,高阶振型的贡献非常有限。工程应用中,需对地震响应的贡献进行量化,以确定需要计算的振型阶数。文中阐述了振型参与质量系数在衡量振型对结构地震响应贡献中的重要作用,明确其在桥梁结构地震响应计算过程中的机理。并对示例进行有限元分析,论证了该理论在工程运用中的正确性。

Usually the seismic response of bridge structures is mainly contributed by the low-order vibration modes,and the contribution of higher modes is so limited that we can neglect it.In order to assign the number of vibration modes that need to be calculated,the contribution of seismic response should be quantified.The theory of modal participating mass ratio is expounded in this paper,which plays an important role in the analysis of seismic response.In the ending,an example is used to demonstrate the correctness of the theory.