Assessing railway vibrations in partially-embedded structures

The increase in railway traffic and train speeds has imposed more demanding conditions on the bridge infrastructure. In response, European standards define strict criteria that must be thoroughly evaluated, often requiring the use of numerical models. The modelling approach depends on both the specific objectives of the analysis and the desired level of accuracy. Among the many factors influencing the dynamic behaviour of a bridge, soil–structure interaction can have a significant impact, which is especially the case of partially-embedded structures such as portal frames. However, this interaction mechanism is often neglected due to its complexity and high computational cost. For this reason, this study proposes an efficient substructuring method to incorporate soil–structure interaction into the dynamic analysis of a portal frame, enabling more realistic and reliable performance predictions. Special attention is given to the experimental identification of the modal parameters and to the evolution of the maximum vibrational response in terms of a few key parameters.