Simulation Of Insertion Loss Of High-Speed Railway Noise Barrier

With the rapid development of High-speed railway in China, the high-speed railway noise pollution becomes a big problem. In order to meet people’s requirements for rail acoustic environment, the investment of high-speed noise control measures including railway noise barrier along the railway line continuously improve. As China’s current major engineering noise reduction measures in railway noise protection, the barrier in railway plays an important role. However, China’s railway noise barrier insertion loss is often less than the design expectations, the reason is that China’s high-speed railway noise barrier insertion loss calculation method used can’t be completely in line with the actual situation of high-speed rail ambient noise.Based on the reduction principles of sound barrier, this article introduces formulas of noise barrier insertion loss and detailed analysis of the impact of the sound source characteristics to insertion loss calculation of the sound barrier. Focus on the high-speed railway noise source characteristics and the prevalence of high-speed rail use sound barrier, indicate that insertion loss calculation method of ordinary sound barrier is not suitable for high-speed railway noise barrier insertion loss calculations.Base on the idea of German Schal103 segment calculation method of multi-source mode, using Cadna/A calculation software to simulate the sound barrier insertion losses in the bridge segment of ChengDu-DuJiangYan intercity railway which the speed of EMU is 200km/h and has set up 2.78m sound barrier. This article obtained the following conclusions:1, By simulating the sound barrier insertion loss which use of single line source the height is ranging from 0m to 3m, we discover that the way it used to simulate the sound of the sound barrier insertion loss is feasible when the receivers is on the deck. The error is within the range of 1.39dB-2.67dB.2, When using dual sound source mode, the best simulation setting whose error is the lowest is that the high emission Lv is 89dB and the low emission Lv is 90dB. The high emission is 0m top of track and the low emission is 5m top of track. In this setting, the sound barrier insertion loss simulation error of the five receiver, which in the section 11,5m away from the track center with the height 0m,lm,2m,3m higher than the track and lm below the track, is in the range-0.71dB～0.99dB;and it is 0.59dB on the receiver 21.5m away from the rail,1m higher than the track; the sound barrier by sound insertion loss simulation errors of two point which are 11.5m from the center of the track section,3m below the track and 5m below the track were 5.02dB,5.85dB.