It is well known that the specific dynamics of traffic at road intersections can greatly influence noise levels in urban and suburban areas. This is especially true when modeling noise at roundabouts, where temporal and spatial variations in vehicle kinematics can cause different noise levels than free-flow traffic on open road segments. Depending on the way noise prediction models account for traffic flow, these dynamic effects are more or less accurately captured.
In this paper, a case study is presented, consisting of a road traffic noise level analysis in the vicinity of three suburban roundabouts in the City of Zagreb. Noise calculations were conducted by means of specialized noise prediction software using static and analytic noise models (modified RLS 90 and European interim method). Accuracy of the obtained noise contour maps was demonstrated by comparing the simulated and the observed noise levels at three receiver points along every roundabout. The aim of this research is to establish the level of reliability of applied noise models and to determine whether they can be used in road traffic noise prediction for suburban roundabouts in Croatia.

noise modeling, roundabout, traffic flow, calculation methods