Study On The Sound Insulation Performance Of High-Speed Track Reducing Load Noise Barriers

Noise barrier is one of the most effective measures to reduce the exterior noise of high-speed trains. It is widely used on high-speed tracks which develop fast in China. With the train speed increasing, the pulsating wind loading reduces the lifespan of the barriers. Thus it is necessary to explore the reducing load barriers. This paper carrys out a study on the sound insulation of noise barriers. The main work and conclusions are as follows:This paper, based on the theories of sound diffraction and transmission, and numerical calculation with the Matlab, analyzes the relationship between the barriers’sound insulation and insertion loss, under the effect of the noises in the areas of wheel/rail and car body. It is found that the critical sound insulation of the noise barrier is, respectively,0.5dB and 3dB, which can assist the design of barriers’sound insulation.The test and analysis of sound insulation of V-type and louver noise barriers in a laboratory are carried out. The experimental results reveal that the sound insulation of V-type barriers is 4 dB more than louver barriers and that the effect of the opening rate, absorption material, thickness and acoustic liner of the sound barrier on the sound insulation performance of it.Based on the 3D finite element method (FEM), the test results and acoustic calculation theory, this paper establishes the acoustic finite element model of the opening barrier. The acoustic model verification is done using the barrier with and without absorption material. Ultimately, based on the verified FEM calculation model, this paper analyzes the effect of the material properties and the structural parameters on the sound insulation of the louver and V-shaped barriers. Finally, the paper further studies better unit board structure and material options for the sound barrier. Prediction results show that the V-type and muffler structure have good sound insulation performance and that optimizing angle, thickness, opening rate, opening panel and absorption material can obviously increase the sound insulation of noise barriers.The further research on the reduction in the aero-dynamical loading on the noise barrier is under way. Due to lacking of theory and test in this field, it needs large amounts of follow-up explorations.