Bridge noise barriers are structures installed between a noise source and the receiver at a certain distance to reduce the noise impact on the receiver, commonly known as high-speed rail noise barriers. The height of the barriers ranges from 1m to 5m, covering an effective area with an average noise reduction of 10 to 15dB (125Hz to 4000Hz, 1/3 octave) and up to 20dB. Generally speaking, the higher the noise barrier or the further away from it, the better the noise reduction effect.