Acoustic characteristics of urban streets in relation to scattering caused by building facades

Accounting for the effect of diffuse reflections and fittings within street canyons, on the sound propagation predicted by ray tracing codes

“…The difference A À A 0 highlights the influence of diffusive reflections on the facades on sound levels attenuation. It confirms results from [11], which is globally an increase of sound levels at short distances and a decrease of sound levels at increased distances. This can be explained by the facade diffusion process, which spreads the energy in all directions.…”

“…The absorption coefficients of the walls vary between 0 and 0.3, which covers the range of the urban facades absorption coefficients [11,25]. The scattering coefficients of the walls vary between 0 and 1, in accordance with previous experimental studies [25].…”

“…Onaga et al showed that the impact of diffuse reflections caused by building facades on sound levels depends on the acoustic characteristics of urban streets: diffuse reflections cause an increase of sound levels at short distances, and a decrease at larger distances; the range of increase is higher in high-facade streets [11]. Moreover, recent studies showed that the shape of balconies can influence significantly sound spectrums [12,13].…”

The contributions of pairs of parallel surfaces in a simple analytical model of room reverberation

“…The objective was to quantify the influence of the scattering properties of the surfaces of the room on the reverberation time. Indeed, we still miss a clear relation between the scattering coefficients and the reverberation, though some recent works have brought interesting contributions to this problem [3][4][5][6].…”

Sound propagation in the vicinity of an isolated building: An experimental investigation

“…5 Many models that attempt to describe the sound field in and around urban street canyons exist, some with supporting experiments and some without. [6][7][8][9] Experimental efforts in urban acoustics have also often been concerned with the sound field in street canyons and the impact of road and train noise. [10][11][12] While some experiments have actually been performed in streets, success has also been achieved by using scale models in experiments.…”