Aerodynamic Interaction of High-Speed Trains with Infrastructure Components

Abstract

Recent projects of alp-crossing tunnels (Brenner Tunnel 57 km, Koralm 33 km, Semmering 27 km) lead to a special focus of investigations in aerodynamic interaction and design concepts for the tunnel equipment. Train passing of High- Speed Rails cause pressure or suction which lead to dynamic loading on sidelong infrastructure components. In tunnels the pressure loads are up to 10 times higher compared to loads on noise barrier walls situated along the open track. The waves are reflected at the tunnel portals and claim the fatigue strength of different tunnel installations. This paper presents exemplary the impact of dynamic interaction and influence on fatigue strength on internal tunnel installations for different tunnel configurations. The pressure loads were taken by using Computational Fluid Dynamics (CFD) analysis calibrated on experimental validations at the Tunnel Simulation Facility Göttingen (TSG) in model scale experiments (1:25). A generic model of the Austrian Railjet manufactured with 3D printing was run at speeds up to 230 km/h. The pressure predicted by CFD compare remarkably well with the measurements. Various configurations of the tunnel cross section and cavities of cross passing of a single track tunnel were tested. The pressure during and after train passage were evaluated, and used for the time-dependent numerical analysis to calculate strain and deformation by the transient loading on tunnel installations. For a typical configuration of installation the technical life span was evaluated and compared with the cumulative damage method after Palmgren- Miner. The Life Cycle Analysis LCA showed that the geometry of shallow cavities of the tunnel walls has only minor influence on the theoretical service life of structural components. However, the numerous wave reflections occurring at the door position after the train has passed has a substantial impact on the service life.