Dynamic analysis of the railway bridge span under moving loads

The first part of the paper provides a review of the state of knowledge of the dynamic behaviour of railway bridges under moving loads. Particular attention is paid to developments in modelling railway bridge loading and dynamic vehicle-span (structure) interaction. The most important aspects determining the advancements in this area of knowledge are identified. The contemporary techniques for defining bridge span finite element models used in dynamic analyses are also discussed. The second, practical part of the paper presents the results of numerical simulations of the passage of load along the bridge structure. The railway loads are represented by a series of concentrated forces and a series of single-mass oscillators. Vibration of the bridge span centre and the vehicle mass depending on the speed of travel are considered. The loading parameters are adopted to represent a real railway vehicle - EN57 electrical multiple unit. The structure’s parameters were adopted on the basis of a 30 m long load-relieving span. In both cases modal identification techniques were used to obtain all the required dynamic parameters of the span under analysis on the basis of experimental data.