Noise barriers are the most widely used form of noise mitigation on European roads managed by National Road Administrations (NRAs). Barriers are manufactured/constructed from a wide variety of materials and to different designs, but all serve the same basic purpose, namely to reduce noise levels at noise sensitive receivers away from the roadside, e.g. at residential properties, by acting upon the sound propagating away from the road by influencing the propagation path between the source and the receiver.
It is important for NRAs to have a robust understanding of noise barriers selected for use on their networks so that there is confidence that the barriers fulfil not only their acoustic function and structural design requirements in accordance with any NRA specifications, contact specifications, etc. but also maintain their acoustic performance characteristics for a reasonably long life with minimal maintenance wherever possible.
This report has been prepared within Work Package 4 of the QUESTIM project with the objective of providing information to NRAs on the acoustic durability of noise barriers and recommendations for the assessment and monitoring of performance.
Standardised tests have been developed for characterising the acoustic performance of noise barriers and other road traffic noise reducing devices and embedded into European standards and thereby the European harmonised specification standard that specifies the performance requirements and methods of evaluation for road traffic noise reducing devices. These test methods focus on intrinsic and not extrinsic characteristics of performance, i.e. the performance of the individual materials or components rather than on how the product is used, since extrinsic measurements will be dependent upon factors such as barrier geometry, topography and distance from the road/noise sensitive receivers.
