Dynamic Response of a Railway Bridge to Heavy Axle-Load Trains Considering Vehicle-Bridge Interaction.

Railway bridges can be particularly sensitive to dynamic effects induced by trains owing to the resonance phenomena originated by periodic loading associated with the passage of regularly spaced train's axles groups. The increase of these dynamic effects in bridges located in freight railway lines, due to heavy axle-loads, higher circulation speeds, and the existence of track irregularities or wheel defects, can lead to excessive bridge vibrations, that can put in risk the structural safety, mainly due to the fatigue phenomena, and wheel-rail contact stability. In this study, the dynamic response of the Suaçuí railway bridge to heavy axle-load trains (HAL) considering the vehicle-structure interaction was analyzed. For this purpose, three-dimensional finite element models of the truss bridge, including the track, and train were developed. The dynamic response was obtained using ABAQUS software based on an iterative uncoupled method for the vehicle-structure interaction and considering track irregularities. The validation of the numerical models was performed through a comparison between the numerical and experimental dynamic responses, in terms of displacements and accelerations of the bridge for the passage of DASH 9W Locomotives and GDE wagons. The experimental response obtained from a dynamic test under railway traffic revealed a good agreement with the numerical response. [ABSTRACT FROM AUTHOR]