Pilotprojekt - Wavebreaker och Tvärbanan2

SWEDEN: Lerum-based start-up Wavebreaker has developed a passive sound damping module designed to mitigate traffic and railway noise in urban environments.

Pilotprojekt - Montering av Wavebreaker bakifrån

Tested in a pilot project with Stockholm transport authority SL last year, the Wavebreaker modules are based on the principle of destructive interference. Sound waves entering the unit are rerouted via a circuitous path, delaying them and causing them to interfere with unaltered waves, cancelling out the noise generated by a passing train.

The modules are designed to be installed on top of noise barriers, and can provide an extra reduction of up to 7 dB(A); this is equivalent to raising the height of the barrier by between 1 m and 2 m.

The company suggests that could allow the use of lower screens, reducing the overall cost of noise protection. It believes that the modules would be particularly useful in dense urban environments, where noise concerns are greatest but high barriers can create a visual obstruction.