高速铁路客站模态特征分析与阻尼模型的注记

针对"房桥合一"高速铁路客站质量、刚度分布严重不均匀、不同阻尼比构件繁多等特点,对其模态特征和用于时程法阻尼模型的确定进行了研究。通过位能加权激励原理和位能公式的阐述、天津西站II区的模态分析与振型分解时程法的应用,并以此为标准进行了5种不同瑞利阻尼比例系数时程法的响应比较。结果表明:位能加权法激励为各模态的振型响应,求得阻尼为振型阻尼,结构模态质量累计数突变发生在第9阶,选择第1,9阶振型确定的瑞利阻尼比例系数较合理。振型分解时程法的振型阻尼可基于振型响应的位能加权法确定,直接时程法的瑞利阻尼宜选择第1阶与模态质量累计数发生突变的振型来确定,可供结构设计与分析参考。

Study on modal characteristics and damping model of a high speed railway station

Irregular stiffness distribution,irregular mass distribution and many kinds of members with different damping models are the characteristics of a high speed railway station.The excitation principle of damping method with potential energy weighted is discussed in detail and the formulation for potential energy is deduced.The modal characteristics of the West Tianjin Raiway Station-II,are analyzed in detail and every modal damping is gotten by using the damping method.Then,the comparison of responses by using 5 direct time-history method with different Rayleigh damping is conducted,where the responses from time-history with modal decomposition is taken as the standard.It is found that the excitation of the damping method is the relative response of every mode,the formulation is in agreement with the results from other researchers,and choosing the first mode and the mode with the mass accumulation coefficient mutation is the more rational way to set the proportional coefficient of Rayleigh damping,which can be a reference for designing and analyzing of similar kind of structures.