Discover the InBridge4EU targets and objectives

InBridge4EU is aligned with the European’s Rail Joint Undertaking (EU-Rail) overall targets in the following domains:

  • Contribute towards the achievement of the Single European Railway Area by defining Europe-wide harmonized standards and interoperability criteria.
  • Improving bridges’ structural analysis to optimise the railway capacity meeting user demand.
  • Establishing criteria for bridges’ structural performance, increasing the quality and consistency of the service.
  • Contributing to reduce the design and maintenance cost of bridges stock, improving the competitiveness of the European rail system overall.


Specific objectives of each Work package

  • WP1 – Definition of Dynamic Line Categories (DTCs) for ensuring compatibility of the interface between trains and bridges: WP1 is designed to address WS1, WS2, WS4, WS5 and part of the WS11, and simultaneously contemplate fundamental inputs from WS9 as well. The main objective of this WP is to improve the practical methods available for determining the train-bridge interface for dynamic loading effects, based on the use of spectral methods and transient dynamic analysis. The spectral methods (DER, LIR) will be reviewed, establishing their precise limitations and proposing improvements in their formulation and application (WS1). The limits of the beam model analysed in WP2 will be considered (WS9). These works will be employed for the development of a new set of DTCs, following the objectives of the “Multiple Unit Classes” first proposed in EN 15528 [4], expanding their applicability and overcoming their limitations to cover all relevant train families and architectures (WS2). Limits of validity to the current static compatibility analysis defined in EN 15528 [4] will also be addressed here (WS11). For this development a comprehensive study of the sensitivity of train parameters will be performed (WS4), as well as the selection of relevant vehicles and train formations to be included (WS5). The resulting DTCs should be i) practical and simple to understand by structural and rolling stock engineers; ii) based on vehicle parameters available to design engineers; iii) applicable in the selection of train formations compatible with the bridge structural performance parameters, i.e., sufficiently fast.
  • WP2 – Identification of critical bridge parameters for the assessment of the economic impact of the new DTCs: This WP addresses WS3, WS6 and WS9. The objective of the WP is to estimate the time and cost of physical works required for implementing each proposed DTC in average on a line. To this end, an extensive set of data from representative bridges of nine lines from five different European Union (EU) countries with maximum speeds in the range [160, 300] km/h will be retrieved and stored in a cloud database. This database, which will also accommodate intermediate and final results from the analyses performed in WP2 different tasks, will be available to the remaining WP. The dynamic response of all the bridges will be obtained both for existing trains, collected in WP1, and in a second phase under the proposed DTCs. The non-compliant bridges will be subjected to detailed dynamic analyses with more comprehensive models, and a final subset of bridges that do not meet the economic technical bridge acceptance criteria will be extracted. For those, an economic evaluation of implementing each proposed DTC on a line will be performed (WS3). In parallel, by means of a thorough statistical analysis of the data base, realistic worst-case combinations of critical parameters in existing bridges for use in parametric studies investigating train/bridge vehicle route compatibility will be identified, in response to the requests in WS6. Finally, the effect of different model updates will be evaluated, with special attention to the adequacy of line beam models for the dynamic analyses of certain bridge configurations (WS9).
  • WP3 – Revision of the dynamic factors φ′ and φ″: This WP addresses WS7. The objective is to propose revised formulae for the dynamic factors φ′ and φ″ stipulated in the Annex C of EN 1991-2 [6], which both improves the current definition and is valid outside the current limits. The study mainly focuses on passenger trains up to 200 km/h and freight traffic up to 120 km/h. A limited study will also be performed for φ″ with application to high-speed lines, partly in collaboration with task 5.4 in WP5. The revised formulae are intended to be used without expertise in bridge dynamics. For cases outside the range of validity, guidance on how to perform dynamic analyses will be given.
  • WP4 – Revision of damping in railway bridges: This WP aims to address the topics described in the WS8. The main objectives consist of estimating damping in different bridge types based on experimental data and identifying the main parameters that most influence the damping values of existing railway bridges and the main reasons for the wide range of damping values observed in similar structures. Recommendations for damping values to be considered in the assessment of existing railway bridges, as well as for developing simplified models of bridges to deal with the radiation damping provided by the soil-structure interaction (SSI) phenomenon will arise from the research carried out in this WP and will be addressed in WP6.
  • WP5 – Revision of bridge deck acceleration limit: This WP addresses WS10. The objective is to provide additional background to a revised limit criteria for vertical bridge deck acceleration. For bridges with ballasted tracks, additional experimental testing under laboratory conditions will be performed, supported by simulations using the discrete element method. For bridges with ballastless tracks, the train-track-bridge interaction models developed in the In2Track3 project [8] will be used to further study the correlation between different derailment criteria and the bridge deck acceleration. The partial safety factors will be studied using the probabilistic framework developed in the projects In2Track2 [9] and In2Track3 [8].
  • WP6 – Recommendations for dynamic compatibility checks, TSIs and Eurocodes: this WP aims to address the requirements envisaged by WS11. The objectives of WP6 consist of proposing recommendations to the regulatory bodies, namely the European Union Agency for Railways (ERA) [10] and the European Committee for Standardization (CEN) [11], for reviewing or implementing updates in the current Eurocodes and Technical Specifications for Interoperability (TSI) based on the research carried out in WP1 to WP5, i.e., to make the bridge between the research outputs and the normative recommendations which arise from this work. A strong coordination between the consortium and the aforementioned organizations is expected through this WP.
  • WP7 – Project coordination, scientific quality assurance and dissemination, exploitation and communication: this WP aims to ensure an effective coordination of the project and to manage common consortium activities, administrative and financial issues, and risks associated with each task, including proposals for mitigation strategies and contingency measures if needed. Moreover, this WP7 is also responsible for ensuring the quality of the scientific and technical outcomes stipulated in the project, as well the dissemination of the key findings of the project to maximize its impact and its outreach to the main stakeholder and target groups.