Vibration analysis of short skew bridges due to railway traffic using analytical and simplified models

Abstract

Skew bridges are common in highways and railway lines when non perpendicular crossings are encountered. The structural effect of skewness is an additional torsion on the bridge deck which may have a considerable effect, making its analysis and design more complex In this paper, the dynamic vibration of skew bridges due to railway traffic including the vehicle-bridge interaction is analysed and studied. An analytical model following 3D beam theory is first developed. Following, a simplified 2D model is also considered which includes only vertical beam bending. Both models are applied to a short skew real bridge from the Spanish railway network. The dynamic responses of the bridge obtained from both models are compared with the results obtained by a 3D FE model. A parametric study for a large number of bridges is performed with the simplified model in order to investigate the influence of various parameters as skew angle, span length and torsion stiffness.