复合QRD型轨道交通声屏障的设计及性能分析

Design and performance analysis of composite QRD rail transit sound barrier

低频噪声绕射问题是目前声屏障设计亟需解决的难题,随着数论扩散体的应用,出现了在声屏障上使用二次余数扩散体(Quadratic Residue Diffusers,QRD)的尝试。但是,由于环境的影响,其工程适用性并不强。以声学传播特性为基础,结合数论扩散体原理并考虑材料使用量提出了一种新型声屏障。用Lms.virtrual.lab软件,采用自动匹配层(Automatic Matched Layer,AML)有限元方法并考虑声振耦合,验证了其应用于轨道交通时优于扩散体复合T型声屏障及传统倒L声屏障的降噪性能,尤其在低频段降噪效果明显,有较高的工程适用性和现实意义。

The problem of low-frequency noise diffraction is a difficult problem that needs to be solved in the current design of sound barriers.With the application of number theory diffusers,the attempts using quadratic residue diffusers(QRD)in sound barriers have been suggested.However,due to the influence of the environment,its engineering applicability is not strong.Based on the acoustic propagation characteristics,combining the principle of number theory diffuser and considering the amount of materials used,a new type of sound barrier is proposed in this paper.By using Lms.virtrual.lab software and AML finite element method and considering acoustic-vibration coupling,it is verified that the noise reduction performance of applying the proposed sound barrier in rail transit is superior to applying diffuser composite T-barrier and traditional L-noise barrier,especially the effect at low frequencies is obvious.So,it has high engineering applicability and practical significance.