Apply Double Layer Sound Absorption System Development and Acoustic Performance Evaluation of Low Height Barrier Near Railways

The most effective way to reduce noise is to reduce the level of the generated noise source or to install a soundproofing facility to reduce noise. In the case of railway noise although there is a method of operating a low noise train as a method of reducing the level of the noise source, this method is practically difficult to apply. In Europe, in order to reduce the rolling noise of railway noise, low height barrier close to the rail was tested on some business line. In this study developed a low height barrier which applied double layer sound absorbing system without increasing sound absorbing material thickness to reduce rolling noise of railway. For this purpose, the acoustic performance of a double-layer sound absorbing system using a high-density polyester sound absorbing material and a single-layer sound absorbing material having the similar thickness of double-layer sound absorbing system of the insertion loss was evaluated. When installing the low height barrier, resonance type muffler was applied to the top of the barrier to prevent increase of train indoor noise due to reflection sound and to reduce diffraction sound. First installed in Rep. of Korea's business line and the acoustic performance was evaluated.