城市郊区公路绿化带的降噪效果研究

Investigation of Noise reduction Effect by Green Belts of Suburban Road

选取柳州市柳北区柳长路绿化林带的全乔木、乔木+灌木、全灌木3种营造模式,根据林带宽度测定其对交通噪声的总降噪值和愈量降噪值,并把3种类型绿化林带的愈量降噪值与相应宽度变化进行回归分析。结果表明,柳州市柳长路全乔木、乔木+灌木、全灌木3类典型绿化营造模式的绿化林带对交通噪声均有一定的降噪效果,但是各绿化林带对交通噪声的效果不一,其中以乔木+灌木营造模式的绿化林带对交通噪声的衰减最大。全乔木、乔木+灌木、全灌木营造模式绿化林带的愈量降噪值与林带宽度的可决系数分别达到0.9783,0.9871,0.9851,林带宽度与噪声愈量衰减存在显著相关性。城市郊区公路绿化林带营造模式应以宽度和类型作为关键考虑因素。

Taken the three types of green belts, all arbors, arbor＋ shrub and all shrubs in Li- uchang Road,Liubei District,Liuzhou City as our objects of study,we tested the noise attenua- tion and excess noise attenuation towards the traffic noise in line with the width of the three types of green belts. According to the analysis of the excess noise attenuation of the three types of green belts in terms of the changes of the width, it shows that the three types of green belts in the said area have a certain effect in decreasing noise, but the effect differs from each type. The best type in traffic noise reduction is the arbor＋shrub. The coefficient of determination be- tween the three types of green belts and excess noise attenuation is 0. 9783, 0. 9871 and 0. 9851 for all arbors, arbor q- shrub and all shrubs, respectively. There are obvious connections be- tween the width of the green belts and the excess noise attenuation value. Therefore,the width and types of the green belts should be taken into consideration when designing the green belts for the suburban road.