Acoustic barriers, primarily used for noise reduction and sound insulation along highways, expressways, elevated composite roads, and other noise sources. They are categorized into pure reflective sound barriers, which are solely designed for sound insulation, and composite sound barriers that combine sound absorption with insulation, being more effective in sound insulation. These refer to wall-like structures installed alongside railways and highways to mitigate the impact of traffic noise on nearby residents. Sound-insulating walls are also known as acoustic barriers. A facility inserted between the sound source and receiver to significantly reduce the propagation of sound waves, thereby diminishing noise impact in a certain area where the receiver is located, is termed an acoustic barrier. They are categorized into traffic noise barriers, equipment noise reduction barriers, industrial boundary sound-insulating barriers, and are widely used on highways and expressways.