Numerical estimation of stresses in railway axles using a train–track interaction model

• Published in: International journal of fatigue 2013-02, Vol.47, p.18-30
• Main Authors: Martínez-Casas, José, Mazzola, Laura, Baeza, Luis, Bruni, Stefano
• Format: Article
• Language: English
• Subjects: Applied sciences; Dynamic loads; Exact sciences and technology; Fatigue; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Railway vehicles; Train–track interaction; Wheelset axle fatigue; Wheelset design
• ISSN: 0142-1123; 1879-3452
• DOI: 10.1016/j.ijfatigue.2012.07.006

► We propose a method to estimate numerically dynamic stresses in a railway axle. ► The method considers train–track interaction and the wheelset’s service profile. ► Dynamic amplification of the quasi-static stresses can be greater than 70%. ► Wheelflats cause high dynamic excitation at low speeds. ► Random rail roughness causes high dynamic excitation at high speeds. The fatigue design of railway axles requires that the stresses arising in the axle in real service are accurately quantified. This paper describes a method to compute the dynamic stresses arising in railway axles as the effect of train–track interaction, based on the numerical simulation of the dynamic interaction between a flexible wheelset and a flexible track. The wheelset is modelled as a flexible rotating body using an Eulerian approach, whereas track is regarded as an infinite periodic system with the rail modelled as a Timoshenko beam resting on discrete elastic supports, considering the inertia associated with the sleepers. The paper presents an application of the proposed procedure to the calculation of the dynamic stresses caused in the axle by different types of geometric imperfection occurring on the wheel and rail surfaces, considering the cases of a single harmonic rail corrugation, random rail roughness and a wheelflat.