The paper presents results of empirical and simulation studies of relationships between the level of noise and level of service (LOS) measures at traffic signal approaches. A comparison of factors used in formulae for traffic noise prediction and measures of effectiveness used for LOS definition, presented in the first part of the paper, shows that those two sets of factors and measures do not overlap and simulation studies and measurements, presented in the second part, were required to investigate relationships between the level of noise and such LOS measures as rate of stopped vehicles, stopped and modified delay, and v/c ratio. Identification of the loudest points and their migration is also described. described. It has been shown that the LOS measures, which are not directly included in the noise prediction expressions as v/c ratio and delay, have a significant impact on the noise level. A significant increase in the noise level with the increase of traffic volumes was observed up to LOS B and C. Directions for future research are suggested in the conclusions. (A)
Abstract