隔震桥梁结构随机地震响应分析的复振型虚拟激励法

Complex mode pseudo excitation method for random seismic response analysis of isolated bridge structures

鉴于隔震支座的本构关系具有显著的非线性,隔震桥梁结构的非线性随机地震响应分析存在理论复杂、计算量大等困难。为简化分析过程和提高计算效率,建立隔震桥梁结构的等效线性化模型并采用非经典阻尼模型描述结构体系的阻尼特性,以复振型叠加法和虚拟激励法为基础,建立了隔震桥梁结构随机地震响应分析的复振型虚拟激励法。数值算例表明,所建立的方法计算效率高,结果可靠、操作方便。

Due to the constitutive relation of isolation bearing having significant non-linearity,nonlinear random seismic response analysis of isolated bridge structures has difficulties of complex theory and large amount of calculation.Here,to simplify analysis process and improve computational efficiency,the equivalent linear model of isolated bridge structures was established and the non-classical damping model was adopted to describe damping characteristics of isolated bridge structures.Based on the complex mode superposition method and the pseudo excitation method,the complex mode pseudo excitation method for random seismic response analysis of isolated bridge structures was established.Numerical examples showed that the established method has high computational efficiency,reliable results and convenient operation.