Sound barriers, primarily used for noise reduction and sound insulation in highways, expressways, elevated composite roads, and other noise sources. They are categorized into reflective sound barriers for pure sound insulation and composite sound barriers that combine sound absorption and insulation, with the latter being more effective in sound insulation. Refers to wall-like structures installed alongside railways and highways to mitigate the impact of vehicle noise on nearby residents. Soundproof walls are also known as sound barriers. 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, such facility is called a sound barrier. Divided into traffic soundproof barriers, equipment noise attenuation soundproof barriers, industrial boundary soundproof barriers, and areas where various types of sound barriers are commonly used on highways and expressways.