Abstract The infrastructure types such as bridge-tunnel connection have become increasingly common along the high-speed railway lines in rugged terrains. The deterioration of traffic safety is inevitable when evoking the sudden variation of aerodynamic load when a train is running at the junction of two infrastructure scenarios (bridge to tunnel or tunnel to bridge) in a windy environment. This study is dedicated to discussing the temporal characteristic of aerodynamic loads acting on a three-car train by simulating an actual running process—running on an tunnel–bridge–tunnel infrastructure in canyon wind environment (TBT-W)—in the CFD software. The dynamic responses of the train when running in the TBT-W scenario, including the displacement and acceleration parameters, the wheel–rail response and the traffic safety indices, are analysed by constructing a wind–train–bridge dynamic coupled system. Results show that the deterioration effect of traffic safety does exist because of the sudden variation in aerodynamic impact at the junction of two infrastructure scenarios with respect to the single infrastructure scenario of bridge under crosswind; the time-resolved effects caused by the rapid transformation of train running scenario remarkably increase the fluctuation amplitudes of the aerodynamic forces and moments; the sudden variation effect of aerodynamic loads when a high-speed train runs in the transition section of tunnel–bridge is more remarkable than that at the bridge–tunnel junction; the wheels in the leeward side, especially for the leading vehicle, present the highest safety risk when running at the tunnel–bridge junction due to the high values of the traffic safety indices.

中文翻译：

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侧风下隧道-桥-隧道情景下高速列车行驶动态响应恶化

摘要 在崎岖地形的高速铁路沿线，桥隧连接等基础设施类型越来越普遍。当列车在大风环境中运行在两个基础设施场景（桥到隧道或隧道到桥）的交汇处时，引起空气动力载荷的突然变化，交通安全的恶化是不可避免的。本研究致力于通过在 CFD 软件中模拟实际运行过程——在峡谷风环境 (TBT-W) 中的隧道-桥梁-隧道基础设施上运行，讨论作用在三节车厢列车上的空气动力载荷的时间特性。列车在TBT-W场景下运行时的动态响应，包括位移和加速度参数、轮轨响应和交通安全指标，通过构建风-车-桥动态耦合系统进行分析。结果表明，相对于侧风下桥梁的单一基础设施情景，两种基础设施情景交界处空气动力冲击的突然变化确实存在交通安全恶化效应；列车运行场景的快速转变引起的时间分辨效应显着增加了气动力和力矩的波动幅度；高速列车在隧道-桥梁过渡段运行时气动载荷的突变效应比在桥-隧道交界处更为显着；背风侧的车轮，尤其是前车，