Bridge Dynamics

As described in the technical note developed by the European Union Agency for Railways (ERA) “ERA technical note on work needed for closing TSI open point on Bridge dynamics” (please refer at https://rail-research.europa.eu/about-europes-rail/europes-rail-reference-documents/additional-technical-material/ ), investigations to formulate a European dynamic interface between railway bridges and rolling stock are needed. New methods must be further developed and should be compatible with the existing regulations in TSI INF, TSI RST, TSI OPE, EN15528 and EN1991-2 with a particular focus on the interface with existing infrastructure.

Using the ZBBD software that will be provided by ERA to the awarded project proposal, the project stemming from this topic shall evaluate the dynamic behavior of the bridges during train passage using the DER method and the time step integration calculation (TSC) for a set of representative bridges together with representative train data.

It is anticipated that in many of the workstreams there will be large volumes of data results as output from the dynamic train / bridge calculations. It is therefore expected the development of optimum methods for ease the visualization of this data and also to enable the efficient identification of significant behavior and critical cases.

The project stemming from this topic shall allocate necessary resources for coordination among other ongoing initiatives on Bridge Dynamic (the DZSF funded project Bridge dynamic: Dynamic load model^[1] ; the S2R funded project IN2TRACK-3^[2]) as well as foresee the creation of an advisory board with ERA and CEN TC250 participation.

All project deliverables shall be of Public nature to ensure adequate exploitation of the results for ERA and Standardization bodies for the TSIs and standards.

Any developed databases are also to be made available and free of charge to ERA and CEN for the implementation and updates of TSI and standards.

The project stemming from this topic shall address all the following workstreams, which can be merged as needed and for efficiency by the applicants in their project proposal work-structure but their content should be addressed in full, including all the specific requirements described in the technical note “ERA technical note on work needed for closing TSI open point on Bridge dynamic” (please refer at https://rail-research.europa.eu/about-europes-rail/europes-rail-reference-documents/additional-technical-material/).

Workstream1: Further development of spectral methods (DER, LIR)

Addressing the needs identified in the chapter 2 of the ERA technical note, the project stemming from this topic shall establish a fast and reliable revised method for defining Train Signature for use in train / bridge compatibility checks.

Workstream 2: Definition of dynamic loading interface between vehicles and bridges

Addressing the needs identified in the chapter 3 of the ERA technical note, the project stemming from this topic shall define the dynamic loading interface between trains and bridges as well as establish a set of ‘Dynamic Train categories’ without the limitations of Multiple Unit Classes in EN 15528:2015 Annex C

Workstream 3: Economic evaluation of proposed Dynamic Train Categories (DTCs)

Addressing the needs identified in the chapter 4 of the ERA technical note, the project stemming from this topic shall undertake dynamic parametric analysis of proposed DTCs, use the results and data obtained from workstream 6 to identify real existing bridges compatible with proposed DTCs / bridges requiring further investigation, undertake initial refinement of bridge dynamic appraisals and optimize DTCs. Additionally, the proposal shall use further refined dynamic bridge analysis techniques to identify which bridges likely to require physical works and estimate time and cost of studies / physical infrastructure upgrade works to implement DTCs on lines.

Workstream 4: Sensitivity studies on train parameters

Addressing the needs identified in the chapter 5 of the ERA technical note, the project stemming from this topic shall identify the critical passenger and freight train parameters and investigate the variation of different train parameters along a train, for example varying axle loads and ratios of regular spacings of axles and the influence coupled multiple units and provide advice on optimizing train design with respect to the dynamic bridge / train interface

Workstream 5: Selection of relevant vehicles in train families

Addressing the needs identified in the chapter 6 of the ERA technical note, the project stemming from this topic shall develop the methodology and criteria for the selection of critical individual trains representing a train family for passenger and freight trains

Workstream 6: Identification of realistic critical parameter combinations for existing bridges

Addressing the needs identified in the chapter 7 of the ERA technical note, the project stemming from this topic shall collect bridge data from different European networks and identify realistic worst-case combinations of critical parameters for existing bridges for use in parametric studies

Workstream 7: Revision of j‘ and j’’

Addressing the needs identified in the chapter 8 of the ERA technical note, the project stemming from this topic shall revise the limits of validity of the existing formulae for j‘ and j‘’ acc. EN 1991-2 and the formulae for j‘ and j‘’ for bridges outside the above-mentioned revised limits of validity up to 200km/hr for passenger traffic and 120km/hr for freight traffic. Additionally, guidance on the significance of the revised formulae for existing bridge recalculations shall be provided

Workstream 8: Revision of damping

Addressing the needs identified in the chapter 9 of the ERA technical note, the project stemming from this topic shall collect and assess measurement data of damping of European bridges and provide more realistic damping values for existing bridges of different construction types.

Workstream 9: Revision of beam model in parametric study to cover other structural forms

Addressing the needs identified in the chapter 10 of the ERA technical note, the project stemming from this topic shall expand the application of current techniques developed for modelling simply supported beams in parametric studies to cover other structural forms like plates, continuous span decks, portal frames, tied arch bridges, truss girder and others. Additionally, advice on how to adjust existing parametric ‘simply supported span’ modelling to take account additional structural forms and more refined methods to address the benefits of the track in distributing axle loads etc. shall be provided.

Workstream 10: Acceleration limit

Addressing the needs identified in the chapter 11 of the ERA technical note, the project stemming from this topic shall undertake the research necessary for specifying adjusted acceleration limit criteria for the evaluation of measured and calculated accelerations for both ballasted and unballasted bridge decks as well as perform physical testing to validate the recommendations

Workstream 11: Revision of limits of validity of static vehicle / bridge compatibility checks

Addressing the needs identified in the chapter 12 of the ERA technical note, the project stemming from this topic shall specify revised criteria that set out when it is necessary to undertake a dynamic analysis check in addition to the normal static based requirements for checking the compatibility of rail vehicles with existing bridges and new bridges, and include recommendations for updating TSI INF, EN 1991-2 and EN 15528

An indicative scheduling of the deliverables is suggested below:

Outcomes under workstream 1 are expected by M18

Outcomes under workstream 2 are expected by M30

Outcomes under workstream 3 are expected by M36

Outcomes under workstream 4 are expected by M12

Outcomes under workstream 5 are expected by M24

Outcomes under workstream 6 are expected by M20

Outcomes under workstream 7 are expected by M36 (intermediate results for j’’ by M15)

Outcomes under workstream 8 are expected by M12

Outcomes under workstream 9 are expected by M24

Outcomes under workstream 10 are expected by M24

Outcomes under workstream 11 are expected by M36

Interactions with other EU-RAIL projects:

The action to be funded under this topic shall share the outputs with ERA and linked projects IN2TRACK3 (101012456) and from EU-RAIL Flagship Area 3 (stemming from the call topic HORIZON-ER-JU-FA3-01), take into consideration the work that they will release and work together for any potential interfaces.

Gender dimension

In this topic the integration of the gender dimension (sex and gender analysis) in research and innovation content is not a mandatory requirement.

[1] https://www.dzsf.bund.de/SharedDocs/Standardartikel/DZSF/EN/project/Project_28_Dynamic_Load_Model.html

[2] https://projects.shift2rail.org/s2r_ip3_n.aspx?p=IN2TRACK3