Environmental noise mapping study for heterogeneous traffic conditions

Traffic noise characteristics in cities belonging to a developing country like India are varied slightly by virtue of the fact that the composition of the traffic is heterogeneous associated with variance in road geometrical features, surface characteristics, honking conditions and varying density of the building on the either side of the road. To study the propagation and spread of the traffic noise in some of the areas a noise mapping study has been attempted along with field measurements of L 10, L 50, L 90 and L eq. In the noise mapping parameters such as L d, L N, L den have been arrived at by taking into consideration the geometrical features of the roads and varying heights of the buildings. In this study noise mapping through computer simulation model (soundplan software) is used by considering several noise sources and propagation of noise to the receiver point. Some of the prediction models such as U.K's CRTN, U.S's TNM and their modified versions have a limited applicability for heterogeneity. Therefore a separate multiple regression model is discussed to suit the heterogeneous traffic conditions for noise mapping purposes.