宁波轨道交通高架段减振轨道降噪效果测试分析

在宁波轨道交通1号线一期工程高架段开展了无声屏障条件下的普通整体道床、梯形轨枕和减振垫道床等三种轨道结构的噪声对比试验,分析了各轨道结构不同测点处噪声的频谱特性,对比了不同轨道结构的实际降噪效果。结果表明:相较于普通整体道床,采用梯形轨枕或减振垫道床后,有的测点噪声减小,但多数测点噪声增大;梯形轨枕和减振垫道床减小了桥梁结构噪声,但同时增大了轮轨噪声;减振垫道床各测点处噪声插入损失均比梯形轨枕大,减振垫道床的降噪效果较梯形轨枕好。

Test and Analysis of Noise Reduction Effect on Vibration Mitigation Track in Ningbo Urban Rail Transit Viaduct

In the condition of silent barrier installed on Ningbo rail transit Line 1,noise tests of three track structures-general monolithic roadbed,ladder sleeper and damping pad roadbed are carried out in the viaduct of Ningbo Line 1 first phase project.Noise spectrum characteristics of different rail structures are analyzed,the actual noise reduction effects of different rail structures are compared.Test results show that on the ladder sleeper roadbed and damping pad roadbed,different from the general monolithic roadbed,the noise on point 1 is increased,while the noise on point 2 and 3 is reduced,the noise on point 4～7 shows an increasing trend.That is to say,though ladder sleeper roadbed and damping pad roadbed could reduce the bridge structure noise,it increases the wheel/rail noise at the same time.The insertion loss of each measuring points on damping pad roadbed is larger than that of ladder sleeper roadbed,so the noise reduction effect on damping pad roadbed is better.