Effect of Aging of Bearings on the Behavior of Single-Span Railway Bridges

Elastomeric bearings are ubiquitous in railway bridges as they provide flexibility that prevents stress concentrations near the supports due to temperature-related material contraction and expansion. Their inherent flexibility affects the overall stiffness and the vibration frequencies of the bridges. Furthermore, the stiffness of the bearings can vary significantly during the lifetime of the bridge due to several factors such as material deterioration and aging and can directly impact the behavior of the bridge. This article investigates the impact of the variations in the stiffness of elastic bearings on the train-induced vibrations on single-span railway bridges. A series of parametric analysis for different train speeds was conducted. The analysis were repeated for a wide-range of bearing stiffness that represents the variation of this parameter during the lifetime of the bridge. The results indicate that, the variations in the bearing stiffness due to aging and deterioration have significant impact on the train-induced vibrations.