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Key Words: Drainage Asphalt Pavemennt, Porous Pavement, Tire/Roard Noise, Sound Propagation, Finite Element Method, Acoustic Absorption Coefficient

STUDY ON THE SOUND PROPAGATION ON THE POROUS PAVEMENT

Masanori MURASE , Satoru KAWAMATA, Minoru KURIKI and Teruhiko MARUYAMA

The sound propagation over the porous pavement surface is discussed in this study. The sound propagation over the porous pavement is calculated by the finite element method (FEM) using the acoustical model of the porous pavement. The sound reduction while propagating over the porous pavement surface, called excess attenuation, is evaluated and found out the effect of porosity, thickness and aggregate size. Since the measured sound reduction of the porous pavement commonly used in Japan is 3 to 5 dB and the calculated attenuation value is around 1dB, the sound reduction effect of the porous pavement is mostly depend on the sound generating mechanism between the tire and the porous pavement surface.