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Acoustic street design Timothy Van Renterghem Free field sound - - PDF document
Acoustic street design Timothy Van Renterghem Free field sound - - PDF document
Introduction Acoustic street design Timothy Van Renterghem Free field sound propagation Ground reflection 1 Specular reflecting facades Ground reflection x=8 m Ground reflection Ground+facade reflection 1000 Hz 1000 Hz 2 Ground+facade
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Ground+facade reflection
x=8 m
Ground+facade reflection
x=8 m
Diffuse reflection
Thomas et al., Journal of the Acoustical Society of America, 2013. Ismael et al., Applied Acoustics, 2005.
a b c d
Diffuse reflection
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Diffuse reflection Diffuse reflection
Picaut et al., Acta Acustica united with Acustica, 2009
Diffuse reflection
Kang, Journal of the Acoustical Society of America, 2000.
facade height=6 m facade height=18 m
Diffuse reflection
Picaut et al., Acta Acustica united with Acustica, 2009
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Balconies
Lowering facade exposure
Direct shielding Balcony details are important Higher storeys better protected
Building up a low-frequency diffuse sound field Changing the street’s directivity pattern
Diffuse reflection Urban street design
Echevarria-Sanchez et al., Building and Environment, 2016
Urban street design
Echevarria-Sanchez et al., Building and Environment, 2016
Urban street design self-shielding windows
Echevarria-Sanchez et al., Building and Environment, 2016
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Urban street design
Echevarria-Sanchez et al., Building and Environment, 2016
model validation
Quantification
Street amplification
Heutschi, Applied Acoustics, 1995. Thomas et al., Journal
- f the Acoustical
Society of America, 2013.
simulations experiments
Diffraction to adjacent canyon
low-frequencies are favoured
Diffraction to adjacent canyon
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Diffraction to adjacent canyon
- nly diffraction
facade reflection+diffraction
Van Renterghem et al., Journal of the Acoustical Society of America, 2010.
Diffraction to adjacent canyon Diffraction to adjacent canyon
Van Renterghem et al., Journal of Sound and Vibration, 2010.
Diffraction to adjacent canyon
Van Renterghem et al., Journal of Sound and Vibration, 2010.
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Diffraction to adjacent canyon Diffraction to adjacent canyon Diffraction to adjacent canyon
Van Renterghem et al., Applied Acoustics, 2006.
Intermediate canyons
1-4 dB excess attenuation/canyon
Rather frequency independent Canyon depth of limited importance Canyon width important
Additive effect QSide engineering model : 1dB/100 m
propagation over roofs in dense urban setting
No absorption, no meteo-effects, no variation in
building height
Multiple canyon propagation
Schiff et al., Applied Acoustics, 2010. Wei et al., Acta Acustica united with Acustica, 2014.
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Street design reduces sound pressure
levels
Promote diffuse reflections Silent zones (pedestrians, facade) Small architectural details can have a strong effect Street amplification mainly governed by street
width
Reductions in streets will help at the non-
directly exposed side (stronger!)
Complex interactions between multiple