铁路车-桥耦合振动仿真分析中现存问题的讨论

Discussion on the Issues Regarding Simulation Analysis in Railway Vehicle-Bridge Coupling Vibration

车桥耦合振动仿真计算模型与算法正确的前提是仿真的过程与实际过程相近或有条件的相近、相似,能反映主要的客观规律。频域分析方法是模型与算法校验和结果分析过程中的重要工具。在对实例进行计算信号和实测信号比较时,不应简单地仅对它们的最大值进行比较,而应更关注两者在频率结构上的异同。由于频率带宽影响加速度信号的最大值,因此,在进行加速度信号的数值比较时,应首先确认、统一所比较的信号的频率带宽。基于实际测试条件和手段的原因,在大多数情况下,用测定的横向振幅代替梁体跨中横向位移,因此在分析比较计算所得的桥梁梁体横向位移和实测横向振幅时,应注意两者的特点和区别。

The preconditions for the correctness of the simulation models and the algorithms of vehicle-bridge coupling vibration depend on the similarity or the conditioned similarity between the simulation process and real case, which can reflect the dominating objective laws. Frequency domain analytical method is an important tool in the process of verifying the models and algorithms as well as analyzing the calculated results. When comparing the calculated signals with the measured signals, one should not simply compare their maximum values. More attentions should be paid on their similarities and differences in frequency structures. Since the frequency bandwidth influences the maximum value of the acceleration signals, the frequency bandwidth of the to-be-compared signals should first be confirmed and integrated before comparing the numerical values of acceleration signals. In most cases, based on the practical test conditions and measures, the lateral displacement of the girder midspan was replaced by the measured lateral amplitude. Consequently, when analyzing and comparing the calculated lateral displacement of the bridge girder with the measured lateral amplitude, both their characteristics and differences should be noticed.