PREDICTION OF ROAD TRAFFIC NOISE CONSIDERING FLUCTUATION OF TRAFFIC FLOW AND CHARACTERISTICS OF SOUND PROPAGATION.

It is no exaggeration to say that noise pollution from road traffic occurs everywhere on trunk roads in Japan. In order to overcome this nuisance, it is necessary to establish a precise prediction method for road traffic noise when noise protections are required from a viewpoint of land use planning and traffic engineering at the step of planning and designing traffic facilities. But it is difficult for the widely used methods, such as environmental assessment in Japan, to satisfy the properties required. Thus, in this paper, the following investigations are covered: (1) development of the noise prediction method considering fluctuation of traffic flow and local variation of sound propagation characteristics; and, (2) estimation and classification of propagation characteristics by a simple experimental technique.