一般化した交通流モデルによる道路交通騒音の静的予測

抄録

As is well-known, the internal physical mechanism of noise generation and propagation which directly have a great influence on the noise fluctuation form, such as the distributions of location of vehicles, the distance between two arbitrary vehicles flowing in the same direction and the number of vehicles in a certain segment on road and the sound propagation environment are most fundamental and important in order to investigate the statistical properties of road traffic noise. Up to now, many approaches for estimating the noise intensity distribution function have been carried out in an idealized case with an exponentially-distributed vehicles model. However, an actual road traffic flow shows too complex pattern to be exactly explained by the above simplified model. In this paper, firstly, we have focused discussions on the prediction problem of distribution form of road traffic noise fluctuation in the near sound field which is important from the viewpoint of noise environmental pollution problem, and we theoretically have derived an explicit expression of probability distribution function and several types of its simplified expression form applicable to the arbitrary road traffic flow containing the idealized traffic model as a special case. Next, we have discussed the relations between theoretical results and well-known previous studies, and shown that our theory includes the well-known previous results as special cases. Finally, we have applied our theory to actual road traffic noise observed in Hiroshima city for purpose of confirming experimentally the legitimacy of our theory.