非定常气动荷载对桥上列车行驶安全舒适性影响分析

为了研究非定常气动力荷载对桥上列车行车安全性和舒适性的影响,结合有限元软件ANSYS和多体动力学软件SIMPACK,建立列车-轨道-桥梁三维多体系统模型,计算风-列车-桥梁耦合系统的动力响应;对比分析定常与非定常气动力荷载作用下桥上列车的行驶安全与舒适性,研究非定常气动力荷载作用下不同横向风速对列车行驶安全的影响。研究结果表明:列车行驶速度为200~300km/h,无风荷载情况下,各安全性与舒适性指标值均满足要求且均小于风荷载作用。横风作用下平均风速为20 m/s,考虑非定常气动力荷载的影响不仅会使列车行驶安全评估结果更安全,还会使列车舒适性评估结果偏于保守。平均风速不超过20 m/s,车速控制在250 km/h,桥上列车行车安全、舒适性均满足要求,且平稳性等级可达到"良好"以上。通过对不同横向风速下桥上列车行驶安全分析,给出桥上列车安全行驶的阈值,为列车的安全运营提供依据。

Impact analysis of unsteady aerodynamic loads on the safety and comfort of trains running on bridges

In order to investigate the influence of unsteady aerodynamic loads on the safety and comfort of trains on the bridge, combined with finite element software ANSYS and multi-body dynamics software SIMPACK, the train-orbit-bridge three-dimensional multi-body system model was established and the dynamic responses of the coupling system was calculated. The driving safety and comfort of the train running on the bridge under steady and unsteady aerodynamic loads were compared and analyzed. The effects of different lateral wind speeds on the driving safety of the train running on the bridge under unsteady aerodynamic loads were studied. The results show that the train travel speed is 200~300 km/h. Under the condition of no wind load, the safety and comfort index values meet the requirements and are less than the wind load. When the average wind speed under cross wind is 20 m/s, it will not only makes the train safety assessment results safer. But it makes the train comfort assessment results conservative by considering the unsteady aerodynamic load. When the average wind speed does not exceed 20 m/s and the vehicle speed is controlled at 250 km/h. The train safety and comfort on the bridge meet the requirements, and the level of stability can reach "good" or above. Through the analysis of the safety of the train on the bridge under different lateral wind speeds, the threshold value of the safe driving of the train on the bridge is given, which will improve the safety operation of the train.