Numerical study of the interaction between a moving oscillator and an infinite beam on elastic foundation with bilinear characteristic

Abstract

This paper presents an analysis of the low frequency vibrations exerted by a simple oscillator travelling along an infinite and uniform beam laid on an elastic foundation having bilinear characteristic. In the railway domain, such a problem is interested because it allows highlighting the influence of the nonlinear track modulus on the interaction between the vehicle and the track. The track model is reduced to an equivalent Euler-Bernoulli beam corresponding to the rail and the inertia of the sleepers, on a bilinear Winkler foundation for the ballast. The vehicle model is a loaded two-degree oscillator representing the wheel, suspension, suspended mass of the carbody corresponding to the wheel (1/4 carbody). The vehicle/track interaction is analysed considering two items: equivalent track modulus and track with bilinear characteristic.