Study on the safety of operating high-speed railway vehicles subjected to crosswinds

A coupled vehicle-track dynamic model is put forward for use in investigating the safety effects of crosswinds on the operation of a high-speed railway vehicle. In this model, the vehicle is modeled as a nonlinear multi-body system, and the ballasted track is modeled as a three-layer discrete elastic support system. The steady aerodynamic forces caused by crosswinds are modeled as ramp-shaped external forces being exerted on the vehicle body. This model was used in a numerical analysis of the dynamic response and dynamic derailment mechanisms of high-speed vehicles subjected to strong crosswinds. The effects of the crosswind speeds, crosswind attack angle, and vehicle speed on the operational safety of the vehicle were examined. The operational safety boundaries of a high-speed vehicle subjected to crosswinds were determined. The numerical results obtained indicate that crosswinds at attack angles of 75° to 90° with respect to the forward direction of the vehicle have a great influence on the safety of operating high-speed railway vehicles. The wheelset unloading limit, which determines the position of the warning boundary dividing the safe operating area and the warning area, is the most conservative, i.e., the safest, criterion to use in assessing the high-speed operational safety of vehicles in crosswinds.概要研究目的随着世界高速铁路网的不断扩张, 高速列车的风致安全性成为高速铁路系统中的关键科学问题之一。 本文利用车辆-轨道耦合动力学理论分析方法, 确定强横风作用下高速铁道车辆的安全运行区域, 为强风地带高速列车的安全控制提供依据。创新要点首次提出了考虑多种影响因素和脱轨评价指标的高速列车脱轨安全域分析方法, 并运用到了高速铁道车辆风致安全性研究中。研究方法基于车辆-轨道耦合动态响应及多种安全性评价指标得到横风作用下高速铁道车辆的安全运行区域和脱轨区域。重要结论铁道车辆安全性评价指标中, 轮重减载率对横风激励最为敏感, 其确定了强风作用下高速车辆安全运行区域的边界。