Study on Comprehensive Noise Reduction Effect of Various Types of Noise Barriers in Chongqing Metro
Synchronous noise test is carried out on the near-track sound field 7.5 m away from the center line of outer rail and the sensitive building in the actual section of various sound barriers in Chongqing metro.The data are analyzed and the prediction model for analyzing noise reduction effect of sound barriers in Chongqing Metro is established,and the comprehensive noise reduction effect of various sound barriers in Chongqing Metro is studied through measurement and simulation.The results show that the anechoic louvered fully enclosed sound barrier has the best overall noise reduction effect,and the corresponding overall noise at the sensitive point of sensitive buildings is 56.4-61.1 dB(A);the 2.5 m upright sound barrier has quite poor overall noise reduction effect,and the corresponding overall noise at the sensitive point of sensitive buildings is 67.8-73.2 dB(A).Another finding is that the simulation result with the use of a single line source model in the case of fully enclosed sound barrier has a larger error in comparison with the actual measurement data,which needs to be corrected by adding a structural noise source and so on.Using the modified prediction model,the predicted noise reduction results are in good agreement with the measured results.Among various sound barriers,the best noise reduction effect for near-track sound field and sensitive buildings is from the fully enclosed sound barrier with muffler louvers at the top,and the measured and the simulated noise reduction effects are 4.9-15.9 dB(A)and 7.7-17.1 dB(A)respectively.
万方数据
维普
