高速列车车体结构共振效应下的耦合振动特性及载荷谱研究

Against the strong coupling characteristic between a certain type of EMU car body structure equivalent loads and structure intrinsic mode, one comprehensive vehicle dynamic coupling calculation method considering structure resonance effect is proposed here.The method can overcome the problem which the random vibration parameters can cause each order coupling analysis insufficient accuracy in the current high-speed train vehicle large system dynamics modeling.At the same time, from the view point of vehicle dynamics, the method based on carbody structure coupling vibration of the resonant effect algorithm and the damage identification method are also proposed here.Firstly, the vehicle vibration characteristics of car body structure and vibration characteristics of suspension device can be studied using the dynamic coupling analysis method.By the rigid-flexible coupled vehicle dynamics model, carbody vibration transfer law can be obtained. According to the actual circuit of the train, the load distributions of carbody and suspension device under different running cases are also calculated .And combining with the measured datum of typical load effect, the fatigue damage process of car body structure are also calculated. Secondly, the carbody loading response law can be obtained through the modal test and calculation results in the low frequency and high frequency.Through the load spectrum extrapolation method and load damage parameter identification technology, car body load characteristics under structure damage can also be considered.Finally, according to the practical technical difficult problem in engineering design, The rationality and accuracy of the algorithm method are performed and some structure design suggestions and improvement measures are put forward.

针对某型动车组车体结构等效荷载与结构固有模态之间的强耦合特征，采用一种全面考虑结构共振效应下的动力学耦合计算方法。该方法可以克服目前高速列车车辆大系统动力学建模中随机振动参数容易导致各阶耦合项分析精度不足的问题。同时，从动力学角度提出完善基于共振效应的耦合振动算法和车体结构损伤识别方法。首先，采用动力学耦合分析方法，研究车辆振动特性对车体结构及悬挂设备的振动特性影响。采用整车刚柔耦合动力学模型研究车体振动传递规律；根据实际线路确定不同车辆运行姿态下车体及悬挂设备的载荷分布；结合实测数据研究典型载荷历程对车体结构疲劳损伤的作用规律。其次，通过试验和计算模态结果分析车体在低频和中高频混合激励作用下的载荷响应规律；通过载荷谱外推方法和载荷损伤参数识别技术研究车体结构损伤条件下的载荷特征。最后，结合车体结构实际工程设计中的技术难题，验证本算法的合理性和准确性，提出车体结构的设计建议和改进措施。

高速列车车体结构及车下悬挂设备共振效应下的耦合振动及载荷谱是研究轨道车辆结构安全的基础理论问题和重要内容。本项目以车体结构为研究对象，重点针对车辆在共振效应下的耦合振动特性及载荷谱问题提出一种新的计算方法。通过该方法的研究，可以克服目前高速列车车辆大系统动力学建模中随机振动参数容易导致动态设计中分析精度不足的问题，完善了基于共振效应的耦合振动算法。另外，本项目还研究了整车动力学特性、载荷谱和结构疲劳寿命的作用机理，提出了现代车辆多学科结构疲劳寿命预测优化设计技术。对高速列车车辆结构的动载荷识别技术与损伤识别技术等前沿性的技术难题开展了相关基础性研究等。总之，本项目完成了项目设定的任务目标和研究内容，解决了高速列车耦合振动效应的一些关键科学技术难题。