Study Of The Noise Field Of The Channel Girder Under Train Load

Vibration and radiated noise caused by the rail transit system involves many research field of structural engineering. There are a lot of works to do in theory and broad application prospects in the practical engineering applications. Compared with the box girder, T beam, Channel beam has the advantages of low building height, low noise pollution, beautiful appearance and so on. It is a new kind of structure form which is suitable for rail transit viaduct. Therefore, this article studies the distribution and characteristic of vibration and radiate noise caused by the vehicle loads.Firstly the paper sums up the theoretical basis about the analysis of the structure vibration response, sound field calculation, and acoustic radiation calculation process. It also presents an algorithm based on the finite element-boundary element theory, and the differences between direct and indirect BEM. After comprehensive comparison, we proposed a method to calculate the vibration radiation noise using indirect boundary elements and to calculate the wheel-rail noise radiation field using direct boundary elements. The finite element program "ANSYS", together with the acoustics device "Virtual.Lab Acoustics" and "Sysnoise", are adopted for simulated analysis of the acoustic radiation characteristics of groove beams, box beams and T-beams. Comparing the dynamic response and acoustic radiation field of different track beams under the vehicle load, by conducting the spectrum response analysis and dynamic time-history analysis, the paper study the sound pressure distribution and propagation law of vibration radiation noise of groove beams. Simulating wheel-rail noise source using Sysnoise, the article analyze the distribution characteristics in the frequency domain and space domain of wheel-rail noise field of track beams. By varying the train operating parameters of the bridge parameters, the paper study its influence law on vibration radiation noise and wheel-rail noise. Thus an effective approach for railway transport noise reduction is proposed.