The integration of travel demand management and technological measures for reducing the level of road traffic noise

Abstract

Noise pollution is one of the major environmental damages caused by automobiles. In 1997 of Japan, 4,135 out of 4,772 roadside observatory stations failed to keep environmental quality standards for noise. Since there has been little improvement in the number of stations satisfying environmental quality standards, we need more powerful actions to change this undesirable situation. In this study, we constructed two models, traffic assignment model and traffic noise model, in order to test several policy measures of roads and road traffic for reducing the level of road traffic noise in a consistent way. The model was built on geographical information system (GIS) and it made the model more operational and easily understood. From a series of Sendai City case studies, the installation of drainage asphalt pavement proved an efficient way of decreasing the level of traffic noise. Porous elastic road surface could abate traffic noise considerably and would be a better measure if the cost would be reduced in future. Cordon pricing, as a measure of road traffic, was effective, but it also worsened the situation in the areas outside the cordon line. The construction of the ring road relieved the serious situation in the city center, but still increased the level of traffic noise in the areas around the cordon line since the ring road itself became the major traffic noise source. Finally the effects of the integrated measures of roads and road traffic were tested and confirmed.