In 1st period the consortium progressed on the Research and Innovation Work Streams
• Urban and mainline measurement campaigns: Extensive noise and vibration measurements were performed on Lyon urban railway network during the passage of trams and light rail on sites with curved and tangent track. A new mainline measurement site selection
was performed due to the disruption of the service initially foreseen in SNCF line.
• Noise in curves: In the context of developing a prediction model for rolling noise in curves, an extension of the TWINS-based approach was implemented. A benchmarking study was conducted to compare available curve squeal noise simulation models. Ongoing work
includes developing models that cover flange and double contact scenarios, statistical approaches, and advanced friction laws. Previously developed models were reviewed and upgraded.
•Transposition, uncertainties and acceptance testing: work is ongoing to improve a methodology for rolling noise transposition between sites, considering differences in rail roughness, track decay rates, and the acoustic transfer function of each site. In this context, a study of
track decay rates has been conducted, showing differences between the procedure described in EN 15610, the wave decay method and indirect estimation methods. Methods for assessing uncertainties in simulated and measured pass-by noise was reviewed. Pass by noise
data for freight wagons were collected, and preliminary review was carried out with the aim of developing a method for virtual certification. Finally, a comprehensive review of the current and near future deployment of battery, hydrogen, and hybrid trains was
performed.
• On-board roughness measurement and rail grinding: An exhaustive review of existing on-board measurement systems was conducted through a literature review, supplier survey and consultation with infrastructure managers: it provides a state-of-the-art overview of
current technologies, operational practices and standardisation gaps. A draft harmonised procedure for converting on-board sensor data into rail roughness indicators aligned with EN 15610 has been developed. This work includes the conceptual design of an open-source
analysis toolbox that will transform the on-board roughness data into roughness levels.
• Track optimisation for noise, vibration and life cycle costs: The objective is to develop a tool capable of optimising railway track systems with respect to Life-Cycle Costs (LCC), noise and vibration. A set of potential Use Cases for track system optimisation was proposed,
supported by an Advisory Board composed of railway experts in noise, vibration, and track engineering. To support tool development, noise and vibration reduction associated with various mitigation measures and combinations of track components were calculated with
the TWINS approach, TRAFFIC software and stored in a dedicated database. Typical installation and maintenance costs associated with each type of track form and each mitigation measure were assembled from a survey of infrastructure managers. To include the
valuation of noise and vibration, a detailed survey and comparison of methodologies used in the EU and various member and non-member countries was performed. A similar survey of the pricing of carbon emissions was conducted. To account for RAMS (Reliability,
Availability, Maintainability and Safety) a qualitative approach was adopted.
• Ground vibration prediction and experiments The main objective is to extend the computational core of the hybrid vibration prediction tool and to collect new experimental data on urban and mainline railways , to verify model predictions.
o Force densities was computed for different rolling stock (tram, metro, light rail) and excitation models were developed for impact excitation due to rail joints.
o A track-independent vehicle indicator (TVI) was developed, supported by an extended parametric study, in which the most important rolling stock, track and soil parameters responsible for vibration emission are identified. The robustness and representativeness of
the proposed TVI were also demonstrated.
o Numerical database with soil impedance and transfer functions was extended and an automated selection procedure developed to return the closest matching soil profile from the numerical database.
o A robust methodology was developed to compute building correction factors, based on three alternative approaches to account for dynamic soil-structure interaction (SSI).
• Hybrid vibration prediction tool: the survey and evaluation of external track, soil and building databases were completed. Relevant data sources were identified and assessed regarding their suitability for vibration prediction and GIS integration. The transfer to a cloud-based
solution was completed. The validated computational core was deployed unchanged in a scalable cloud environment, combined with a redesigned user interface and workflow.
