冲压机械振动对高铁桥梁及行车动力影响分析

高速铁路桥梁的平顺性和稳定性对运营列车的平稳性和安全性有很大影响。为研究冲压机械产生的外部振动激励对高铁桥梁的影响,首先通过对此机械引起的地面振动进行实测,并结合有限元分析软件,确定最大冲击荷载作用下产生的地面振动及传播至桥墩处的振动;然后通过建立列车-轨道-桥梁耦合动力学模型,将桥墩处的地面振动作为激励输入,分析列车以不同速度通过时车辆、桥梁动力学响应。结果表明:地面冲击振动有限元模型计算结果与实测结果基本相符,验证了模型的可靠性;地面振动对桥梁响应会产生一定的影响,距振源50 m处地面振动对桥梁所产生的影响较距振源80 m处(桥墩处)的大,但对运行车辆的影响很小;随着车速由250 km/h至350 km/h,车辆及桥梁各结构的动态响应均有所增大,但都未超出安全限值。因此,冲压机械冲击作用导致的地面振动对列车-轨道-桥梁系统动态服役性能影响非常有限。

Analysis of Stamping Machinery Vibration Impact on High-speed Railway Bridge and Traffic

The stability and smoothness of high-speed railway bridges have significant influence on the stability and safety of operating trains. In order to study the influence of external vibration excitation induced by stamping machines on high-speed railway bridges, this paper firstly measures the ground vibration caused by the machines based on the field test, and then, by using the finite element analysis software, determines the ground vibration characteristics and vibration level of the ground surface located at the pier under the maximum impact load. Finally, a train-track-bridge coupling dynamical model is established and the response of the ground vibration at the pier is inputted into this dynamical model as an external excitation so as to analyze the dynamic response of the vehicle and bridge at different train speed. The results show that the calculation results obtained by the finite element model of ground impact vibration are in good agreement with the test results, validating the reliability of the model; the ground vibration has certain influence on the response of the bridge; the ground vibration at 50 m from the vibration source has larger influence on the bridge than at 80 m away from the vibration source(at the pier), but it has a little effect on the running vehicle; at the speed from 250 km/h to 350 km/h, the dynamical response of the vehicle and the bridge increases, but does not exceed the limit values. Therefore, the ground vibration caused by the impact of stamping machinery has very limited influence on the dynamic service performance of the train-track-bridge system.