DOI 10.1393/ncc/i2006-10030-2 IL NUOVO CIMENTO Vol. 30 C, N. 2 Marzo-Aprile 2007 Errors evaluation in the estimate of the noise from the road traffic G. Zambon, S. Radaelli and E. Sindoni Dipartimento di Scienze dell’Ambiente e del Territorio, Universit` a degli Studi Milano-Bicocca Milano, Italy (ricevuto il 19 Ottobre 2006; revisionato il 16 Gennaio 2007; approvato il 31 Gennaio 2007; pubblicato online il 12 Aprile 2007) Summary. — Specific algorithms together with noise data acquired during a mea- surement campaign, consisting of approximately 80 one-hour records, were utilized to model the noise levels of a road network. Experimental measurements were used to evaluate the reliability of the model by analyzing the differences between the measured values and the estimated ones. We think that these differences have to be especially ascribed to an imperfect representation of the combined effects of the attenuation due to acoustic wave diffraction and the attenuation produced by the ground effect. PACS 43.28.Hr – Outdoor sound sources. PACS 43.28.Js – Numerical models for outdoor propagation. PACS 43.30.Zk – Experimental modeling. PACS 43.50.Lj – Transportation noise sources: air, road, rail, and marine vehicles. PACS 43.50.Rq – Environmental noise, measurement, analysis, statistical charac- teristics. 1. – Introduction In order to evaluate the acoustic noise produced by wide sound sources, as suburban road network, it is necessary to make use of suitable simulated models. A problem resulting from this process is the uncertainty in the allocation of the sound noise levels close to the receptors. The aim of the present work is to quantify these uncertainties, in particular in the application of the main algorithms now applied in Europe for the road traffic noise simulation. The first part of this work deals with a study to define a procedure to identify the areas, within the ranges acoustically affected by road networks, where the enforced noise level thresholds are exceeded. Specific algorithms together with noise data acquired during a measurement campaign consisting of approximately 80 one- hour records were utilized to model the noise levels in the vicinity of a road network. The experimental measurements were used to evaluate the reliability of the model by analyzing the differences between the measured values and the estimated ones. The results from three different algorithms normally used to evaluate the noise from the road traffic have been afterwards compared. c  Societ` a Italiana di Fisica 187 brought to you by CORE View metadata, citation and similar papers at core.ac.uk provided by Scientific Open-access Literature Archive and Repository