考虑轨道不平顺的车-桥动力分析

考虑轨道不平顺，采用整体车辆和桥梁组合的计算模型。对高架轨道进行车-桥动力分析。对给定的功率谱密度函数，构造等效的频谱幅值和随机相位后再作Fourier逆变换来模拟轨道不平顺，结果表明新方法比通常的三角级数法更为有效，对于轨道平顺及不平顺两种情况，针对两种车速计算车体和桥梁的动力反应。结果表明，轨道不平顺以及车速提高对桥梁跨中位移的影响较小，但对桥梁跨中加速度的影响较大而且高频反应明显增大。轨道不平顺对车体振动的影响较大，振动的幅值和频率都大大提高，车速增大时，尽管车体加速度反应明显增大，但是其位移则变化不大。同时，采用模拟与实测两种不平顺样本的计算结果表明，本文采用功率谱密度函数的模拟方法可以基本反映轨道的实际不平顺情况。

Dynamic Analysis of Train-bridge System Considering Rail lrregularity

Dynamic analysis was used by train-bridge model to elevated railway system considering rail irregularity. The rail irregularity was simulated by a new method - first getting the spectral amplitude corresponding to given power spectral density function and the stochastic phrase, and then doing inverse Fourier transform. The result shows it is more effective than often used triangular series method. The dynamic response of train-bridge was calculated at two different speeds respective to the condition with and without rail irregularity. The result denotes that although rail irregularity and faster speed affect bridge middle span displacement little, these will increase train's acceleration greatly, and vibration frequency is much more higher. The rail irregularity increases train's vibration response tremendously on both amplitude and frequency. Though the train's acceleration increases greatly with faster speed, its displacement is changed little. The calculation results using simulated and measured irregularity indicate that the power spectral density function and the simulated method used here can reflect true condition of rail.