In-situ evaluation of the acoustic efficiency of a green wall in urban area

David Lunain (1) , David Ecotiere (2) , Benoit Gauvreau (3)

1 Cerema Direction Méditerranée - Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Direction Méditerranée
2 UMRAE - Unité Mixte de Recherche en Acoustique Environnementale
3 IFSTTAR/AME/LAE - Laboratoire d'Acoustique Environnementale

Which help to give back space to plants in towns. The primary purpose of this type of device is very often an aesthetic issue but the question of using them to reduce noise may arise. In this context, and as part of a French research project involving other scientific topics, an acoustic measurement campaign was conducted by Cerema around a green wall site (rue de la Préfecture in Cergy, near Paris). The evaluation involved the characterization of the street sound environment, before and after setting up the wall: - by directly measuring the road traffic noise. - by collecting acoustic signals generated by an omnidirectional speaker. It is shown that the infrastructure tends to reduce noise levels in the street, by observing: - moderate noise reduction (between 0 and 6 dB gain) at medium frequency (400-2500 Hz) that can be put down to acoustic absorption due to the planting substrate. - maximum efficiency at high frequency (between 0 and 10 dB of gain above 3150 Hz) where a scattering phenomenon caused by the foliage also comes into play.

Mots clés: SON; BRUIT; ACOUSTIQUE; AMBIANCE SONORE

Domaines: Acoustique [physics.class-ph]

David Lunain, David Ecotiere, Benoit Gauvreau. In-situ evaluation of the acoustic efficiency of a green wall in urban area. Internoise 2016, 45th International Congress and Exposition of Noise Control Engineering, Aug 2016, HAMBOURG, Germany. pp. 6592-6601. ⟨hal-01382576v2⟩