Acoustic barriers, primarily used for noise reduction and sound insulation in roadways, highways, elevated composite roads, and other noise sources. They are categorized into reflective acoustic barriers, which are purely for sound insulation, and composite acoustic barriers that combine sound absorption and insulation, the latter being a more effective sound insulation method. These refer to wall-like structures installed alongside railways and highways to mitigate the impact of vehicle noise on nearby residents. Sound-insulating walls are also known as acoustic barriers. An acoustic barrier is a facility inserted between the sound source and the receiver to significantly reduce the propagation of sound waves, thereby diminishing the noise impact in a certain area where the receiver is located. These are classified into traffic noise-insulating barriers, equipment noise attenuation sound-insulating barriers, industrial boundary noise-insulating barriers, and they are commonly used on roads and highways.