Assessment of traffic noise for medium heavy vehicles in octave bands

Abstract

Abstract The paper presents the analysis results of medium heavy vehicle traffic measurements which were used to simulate the noise measurands. The Cnossos-EU model were used for this purpose. The medium heavy vehicle traffic volume and velocity were recorded by permanent automatic sound and traffic monitoring station. The noise was calculated in octave bands according to the Cnossos-EU model. The results were described using parameters such as the median, average peak level – C90, average background noise level – C10, percentiles C25 and C75. Analyzes carried out for the tested section of the road showed that the traffic of medium heavy vehicles is one of the main source of road noise. It has been shown that maximum values of the equivalent sound level occur for the frequency of f0 = 1 kHz. The positional measures of traffic noise were proposed for data scattering. The dispersion of noise and type A uncertainty of the results were evaluated. It was found that in most cases, the distribution of the tested variable was not normal. It was notice a lack of symmetry between the time distribution of traffic flow of vehicles entering and leaving the city.