Assessment of the dynamic response of high-speed railway bridges in interoperable lines

Abstract

In this work, dynamic analyses of different structural types of bridges under high- speed railway loading were carried out, towards the assessment of its dynamic behaviour in interoperable lines, in which theTechnical Specifications for Interoperability (TSI) are applicable. The analyses were made for the passage of real trains and the loading schemes relative to the High Speed Load Model. The responses were evaluated from the point of view of structural safety, track safety and passengers comfort, based on the criteria established in the EN1991-2 and EN1990-AnnexA2. A high-speed railway system is presently under implementation in Portugal, which will enable the connection of the country with a large European network. At the moment, many countries have already developed their own structural solutions for dealing with the effects of high-speed trains in bridges and a great number of structures have been in operation for several years. These solutions were initially designed for specific train types, thus being checked for the dynamic effects of only a small part of the actual European high-speed rail traffic. In the case of interoperable lines, as will be the future Portuguese high-speed network, the high-speed Technical Specifications for Interoperability (TSI) (1) are applicable, requiring additional checks for dynamic analysis using the High-Speed Load Model (HSLM). In this paper the dynamic behaviour of different types of bridges is investigated, namely for a metallic bowstring arch bridge, existing in a conventional line, a prestressed concrete voided slab bridge, a prestressed concrete box girder bridge and a composite twin girder bridge, part of high-speed railway lines. Dynamic analyses of these structures were performed for both the actual high-speed real trains and the HSLM load schemes, in an attempt to infer the consequences of the application of these new models to the design of railway bridges. The response of the bridges were assessed in terms of structural safety, track safety and passengers comfort, based on the most recent criteria established in the EN1991-2 (2) and EN1990-AnnexA2 (3).