关键词: 声屏障, 声学超构, 吸声, 隔声, 隔声量

Abstract: In order to effectively solve the pain points such as material escape, aging, collapse, hardening and performance degradation of porous sound absorbing materials of existing railway sound barriers, the most cutting-edge and popular noise reduction technology, acoustic superstructure technology, is introduced. Specifically, the mechanism of "non-local coupling of weak sound absorbing units" is adopted, and a multi-cavity parallel internal catheter-type Helmholtz resonance structure is designed. The measured results show that the noise reduction coefficient of the sound barrier with the new structure is 0.83, and the weight insulation is 38.3 dB, which exceeds the technical requirements of TB/T 3122-2019. Further simulation tests are carried out, and the results show that sound reduction index of the sound barrier with the new structure is 4.5 dB higher than that with the existing cotton structure. The sound barrier of the new structure has significant technical advantages in the design of low frequency noise reduction and has important application value.

Key words: sound barrier, acoustic superstructure, absorb sound, sound insulation, sound reduction index