轻轨桥架声屏障优化设计研究

随着城市轻轨建设的发展,交通噪声污染逐渐引起人们重视。在轻轨桥架两侧设置声屏障是控制轨道噪声的重要措施之一。声屏障的高昂成本往往是由不合理的设计参数造成的,通过对目前声屏障设计方法进行分析,提出了轻轨桥架声屏障优化设计方法。该方法以声屏障建造成本为目标函数,以降噪要求为声学约束,综合考虑设置位置、高度和长度等设计变量的影响;由列车噪声1/3倍频程频谱计算插入损失,提高了优化过程中插入损失的计算精度。该优化设计法与目前设计方法对比,验证了声屏障优化设计在改善降噪性能和经济性能方面的优越性。讨论了设计参数对成本和降噪性能的影响,并且对轨边矮墙的降噪性能进行了分析,所获的结论对声屏障和轨边矮墙设计参数与形状的选择具有指导意义。

Study on Design Optimization of Noise Barrier along Rail Transit Bridge

As the construction of rail transit develops, people are more and mo re concerned about the noise pollution. To install noise barriers along both sid es of a rail transit bridge is one of the main measures for controlling the nois e caused by the rail transit. High cost of noise barrier is usually caused by im proper design parameters. Through the analysis of current design of barriers, an optimized design is presented, in which the cost of noise barrier is chosen as an objective function, the requirement of noise reduction as the acoustic constr aint, and the installment position, height and length are considered comprehensi vely. Insertion loss is calculated by one third of octave band of representative spectra, so that the precision of calculation in insertion loss in optimization process is raised. After compared with current design method, the advantages of the new method in noise reduction and improvement in economic cost of the optim ized design are verified. The effects of design parameters on cost of noise barr ier and noise reduction are discussed, the effect of noise reduction by tracksid e low barriers is analyzed, and the results are instructive to the selection of the design parameters and shape of barrier.