Presentations and Papers
Summary - Mitigation of Curve Squeal Noise
Presenter: David Roberts
At CORE 2004 the authors presented a first paper on the control of Noise and Vibration on the Epping to Chatswood Rail Link (ECRL) project. That paper considered design requirements, the approach to acoustic modelling and preliminary track design. Given the position in the project programme, the paper stopped short of detailed design and construction issues. There has been much development in the intervening 4 years and this second paper completes the story, highlighting the processes used for validating the acoustic model, detailed engineering design issues, construction methodologies and the resolution of construction problems encountered.
With commissioning of the project ongoing throughout 2008, this paper provides an update on the refinement of the proposed extent of track treatments (use of track types) through research and site-specific testing to validate the acoustic model, including ‘ground’ propagation tests to provide a more accurate assessment of the vibration propagation characteristics of the rock along the tunnel’s route and further measurements of input vibration levels at the rail / wheel interface. This latter work will be used to give an overview of the impact of track maintenance on generated vibration levels.
In addition to the acoustic design, the paper considers the structural design of the slab systems, including the development of specifications for rail fasteners and slab bearings. It goes on to present a summary and findings of the debate on the use of ‘long’ v ersus ‘short’ ( mini) slab Floating Slab Track (FST) systems and the innovative internal ‘bracing key’ c oncept adopted for the lateral and longitudinal restraint of the slabs.
The paper concludes with a discussion of the construction methodologies developed for both Direct Fixation Fastener (DFF) and FST slab types, highlighting the issues and problems encountered during site operations and any problems were solved. As a final footnote the paper examines the last remaining area of work – validation testing under full service conditions.
Download Proceedings
