Handling sound propagation attenuation over a housing area

摘要

Three models are relevant in evaluating socio-economic cost of traffic noise: a noise pricingrnmodel which formulates a yearly socio-economic cost for each dB reduction, an acousticalrnmodel which determines traffic noise levels in the front of each house, and a distributionrnmodel which specifies the number of inhabitants for each dB interval. For a given distancernand a receiver height, sound propagation attenuation varies in a certain extent dependingrnon distance, due to variations in shielding effect, in local ground elevation/attenuation, etc.rnAccordingly, such sound propagation attenuation shall, as proposed in this work, berndescribed in two parts: a representative sound attenuation pattern and a scatteringrndistribution function. The studied example is a noise mapping result for a housing area ofrnabout 3100 dwellings. Based on the noise mapping data, a distance-dependent standardrndeviation function was worked out. Together with the use of the Gaussian distribution, thisrndistribution function can, as believed, describe the scattering feature. In Sweden, fourrntypical sound attenuation patterns have officially been accepted. Expected, representativernstandard deviation patterns will also be worked out in near future. Then, a quickrnestimation of the socio-economic cost, independent of costly noise mappings, will becomernpossible.