Dynamic amplification in a periodic structure with a transition zone subject to a moving load: Three different phenomena

The study of periodic systems under the action of moving loads is of high practical importance in railway, road, and bridge engineering, among others. Even though plenty of studies focus on periodic systems, few of them are dedicated to the influence of a local inhomogeneous region, a so-called transition zone, on the dynamic response. In...

Transition radiation in a nonlinear and infinite one-dimensional structure: a comparison of solution methods

Transition zones in railway tracks are locations with a significant variation of track properties (i.e. foundation stiffness) encountered near structures such as bridges and tunnels. Due to strong amplification of the track’s response, transition zones are prone to rapid degradation. To investigate the degradation mechanisms in transition...

A lattice model for transition zones in ballasted railway tracks

The procedure presented in this work aims at providing a framework for studying settlement of ballast in zones with stiffness variation of the railway track support. The proposed procedure results from expanding an existing infinite periodic model of a railway track to account for variations in the stiffness of the foundation. Ballast is...

Transition radiation in an infinite one-dimensional structure interacting with a moving oscillator—the Green's function method

Transition zones in railway tracks are areas with considerable variation of track properties (e.g., foundation stiffness) which may cause strong amplification of the response, leading to rapid degradation of the track geometry. Two possible indicators of degradation in the supporting structure are identified, namely the wheel-rail contact...

Transition radiation in a piecewise-linear and infinite one-dimensional structure–a Laplace transform method

Transition zones in railway tracks are areas with considerable variation of track properties (i.e., foundation stiffness) encountered near structures such as bridges and tunnels. Due to strong amplification of the response, transition zones require frequent maintenance. To better understand the underlying degradation mechanisms, a one...