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Key Words: noise barrier, road traffic noise, low noise pavement, porous asphalt, diffraction, Interference, BEM, visualization

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DEVELOPMENT OF DOUBLE Y-SHAPED NOISE BARRIER USED TOGETHER WITH LOW NOISE PAVEMENT

Hiroshi SHIMA, Toshiyuki WATANABE, Teruhiko MARUYAMA

A newly developed double Y-shaped noise barrier, which has large noise reduction effect at low frequencies, is proposed. So far, noise reduction by conventional noise barrier are quite difficult on porous asphalt pavement since they are usually not effective for lower frequencies. The barrier has double Y-shaped structure - so its two branched walls also have a branched wall. The barrier shows as much as 5dB noise reduction on porous asphalt pavement.

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