高速铁路不同高度声屏障的降噪效果分析

Analysis on Noise Reduction Effect of Sound Barriers with Different Heights for High Speed Railway

为探究不同高度声屏障对高速铁路噪声的降噪效果,采用有限元软件ANSYS并参照武广高铁相关试验段建立声屏障降噪模型。采用声学分析软件SYSNOISE仿真研究3,4,5和6m这4种不同高度直立型反射声屏障的降噪效果。结果表明：在与声屏障法线方向平行且距离轨面1.5和3.5m高的平面内,声屏障高度从3m增加到4m对降噪效果的提高有限,再从4m增加到5m降噪效果显著提高,而声屏障高度超过5m后对降噪效果的继续提高也不明显;在与声屏障法线方向垂直且距离轨道中心线30m的平面内,随着声屏障高度的增加,在距地面15m高以下区域,声屏障高度的变化对噪声级影响较大,但超过此范围影响不大。噪声衰减与声屏障高度并非简单的线性关系,在同时考虑降噪需要和声屏障成本的情况下,高速铁路路基区段声屏障的合适高度为4~5m。

With finite element software ANSYS and based on a certain test section of Wuhan-Guangzhou high speed railway,a noise reduction model of sound barrier for high speed railway was established to study the noise reduction effect of sound barriers with different heights.By the acoustic analysis software SYSNOISE,the noise reduction effects of the vertical type of reflection noise barrier with the heights of 3,4,5and 6 m were simulated and analyzed.Results showed that,in the plane which was parallel to the normal of sound barrier and 1.5mor 3.5mabove rail surface,the noise reduction effect was not satisfactorily improved by increasing the height of the sound barrier from 3mto 4m.Then the noise reduction effect was significantly improved by increasing the height of the sound barrier from 4mto 5m.But when the height was above 5m,the continuous improvement in the noise reduction effect was not obvious.In the plane which was vertical to the normal of sound barrier and 30 maway from the center line of track,with the increase of sound barrier height,in the area 15 mabove ground,the change in the height of sound barrier had great impact on the noise level.However,the impact was little beyond the area.The relationship between noise attenuation and the height of sound barrier was not simply a linear one.According to the need for noise reduction and the cost of sound barrier,it is suggested that the suitable height of the sound barrier for high speed railway in subgrade section should be from 4mto 5m.