Spatial variations in pedestrian soundscape evaluation of traffic noise

Walking is necessary for experiencing urban space, but pedestrians are seriously disturbed by traffic noise. This study aimed to clarify spatial variations in soundscape evaluation in pedestrian spaces used solely for walking, including traffic noise annoyance, the dominance of various sound sources, and the perceptual dimensions of the soundscape. Three traffic noise level areas, at various distances from the road, were evaluated in a typical pedestrian space in China, using a questionnaire survey in an on-site study. The results reveal that, first, the soundscape evaluations in the high-noise area (70 dBA) and middle-noise area (60 dBA) are more similar, but present a larger difference with the low-noise area (50 dBA). The latter is more complicated, and more subjective evaluations in this area are required than for higher sound-level areas. Second, the correlation between the soundscape evaluations of the middle-noise area and the low-noise area demonstrates more similarity, but presents a larger difference with the high-noise area, meaning the effectiveness in the high-noise area may differ from lower sound level areas even with the same soundscape improvement measures. Finally, the relationship of the dominance of natural sound with other soundscape evaluations become weaker as the distance from the road increases; this means that deliberately increasing natural sound might be an effective method to improve the soundscape quality in the high-noise area. These findings can provide a reference for soundscape evaluations and landscape design in pedestrian spaces where traffic noise is a problem.