Analysis of Aerodynamic Impact induced by High Speed Trains

Structures such as noise-barrier walls along high-speed railway lines are subject to aerodynamic excitations caused by alternating overpressure and underpressure loads induced by passing trains. This paper presents the results from holistic investigations during in-situ measurements at a new train high speed track in Austria. Trains moving quickly create an aerodynamic bow wave, comprised of a rapid alternation of overpressures and underpressures, as well as an aerodynamic stern wave, comprised of a rapid alternation of underpressures and overpressures. The amplitude of these waves depends on various factors, including the shape of the front and the back of the train and its velocity. A passing train thus causes cycles of overpressure and underpressure to act on any structures near the track, such as noise-barrier walls. The intensity of the load also depends on various factors, including the distance of the wall from the track. These effects cause cyclical stresses at a frequency of several per second. Due to the significant influence of the trains´ aerodynamic shape, in-situ measurements for the determination of the aerodynamic impact of different train types were carried out. The test bed area was located between Vienna and St. Pölten, maximum speed drives were operated by ICE trains with a measured train velocity of 336km/h. In this paper the functional correlation between the dynamic excitation and the dynamic characteristics of noise barrier walls are discussed.