Situated at the cross-point of the Rolling Stock and the Track areas, the Train Track Interaction Sector is a platform where experts of vehicles and infrastructure can meet together to consider trains and tracks in a system view.
The Train Track Interaction Sector mainly covers the area of wheel-rail contact mechanics and the area of pass-by noise and vibrations.
Through its projects and activities, the Train Track Interaction Sector is seeking optimum and harmonized solutions based on a system approach combining the expertise of RU and IM rather than unilateral solutions of only one side
Its strategy and objectives are fully in line with the general targets of the Rail System Forum, and rest on the common pillars of standardisation, research and benchmarking. They can be identified within two main strategic axes:
- The improvement of the design and certification process: aiming at enhancing knowledge and tools in order to facilitate, optimize and speed up the design and the certification process. Virtual certification being eventually the preferred alternative to costly and time consuming empiric procedures.
- The development of techniques for the management of operational conditions, to constantly monitor and ensure that the railway system in operation still complies with its design specifications and with the certification criteria.
The Train Track Interaction Sector is chaired by Mr. Pierre-Etienne Gautier (Systra).
Projects and activities
The UIC project "Equivalent Conicity for Tracks aimed at providing an overview of track data results and delivering a proposal for usable limit values of equivalent conicity for tracks.
A standardised protocol for the determination of the track equivalent conicity for this project was agreed in Phase 1 of the project. Map of wheel-rail contact conditions of different railway lines in European networks was completed in Phase 2 of the project. Two standard design wheel profiles defined in EN 13715 were used, S1002 (SR=1425mm) and EPS (SR=1420mm), to calculate equivalent conicity with measured rail profiles. Rail profiles measured from four defined speed categories track sections were used. In Phase 3, analysis of the established map of contact conditions were undertaken and recommendations given for closing open points in both INF and RST TSIs.
Wheels of wagons equipped with LL-block brakes tend to exhibit wear patterns which, under certain configurations, might increase equivalent conicity and generate running instability, as recorded during the first part of the Europe Train project experimental runs. Although the affected vehicles still comply with the safety limits specified in UIC 518, this might have some undesirable effects on the track. The fatigue behaviour of track components and the acceptability in terms of fatigue, for the infrastructure, of repeated oscillating movement related to hunting behavior and generating high track forces need to be assessed. This project seeks to check the acceptable limits of vehicle instability regarding the track. It will investigate the influence of some experienced wheel/rail force signals on track resistance and on the fatigue of track components. At first, numerical analysis will allow deriving the wheel/rail contact force signals applied on the track, from the measured accelerations. Laboratory experiments at real scale will then be carried out to assess the global track stability under different conditions (including effect of tamping, of under sleeper pads) and to evaluate the effect of repeated instability on the fatigue of rail, fastening systems and ballast.
European Rail Research Advisory Council
Noise Roadmap into research projects
On April 10th 2013, within the framework the Train Track Interaction Sector activities, UIC organised an international Seminar on Acoustics and Vibration. Articulated around four thematic workshops introduced by high level keynotes, the seminar made it possible for the experts to draw up an inventory of some current concerns, issues and challenges regarding railway-originated noise and vibrations. See details and download the presentations here...