Characteristics of Noise Caused by Trains Passing on Urban Rail Transit Viaducts

With the large-scale construction of urban rail transit viaducts in China, the noise problem caused by trains traversing these sections has become increasingly prominent and a key technical challenge that restricts the sustainable development of rail transit. There are two main noise sources when trains pass on rail transit viaducts, namely, wheel-rail noise (WRN) and bridge-borne noise (BBN). However, most of the existing rail transit viaduct noise prediction models consider only a single noise source. In this study, a total noise prediction model incorporating both WRN and BBN was established using the finite element method (FEM), the boundary element method (BEM), and statistical energy analysis (SEA). The viaducts of Wuhan Metro Line 2 were selected as the research object, and noise tests of trains passing on the viaducts were carried out to validate the total noise prediction model. Based on the validated model, the spatial distribution characteristics and attenuation laws of the total noise were investigated, along with the influence of train speed on the total noise. The results show that the prediction model accurately simulated the total noise caused by trains passing on viaducts. When a train passed on the viaduct at a speed of 60 km/h, the total noise near the viaduct reached 88 dB(A) and decreased with the increase in the distance; at 120 m from the track centerline, the total noise decreased to less than 57 dB(A). As the distance increased, the total noise diminished across the entire frequency spectrum. Notably, low-frequency noise decayed at a slower rate than high-frequency noise. As the distance from the track centerline doubled, the total noise decreased by about 4.23 dB(A). The total noise increased with train speed. When the train speed doubled, the total noise at 30 m and 120 m from the track centerline increased by 6.32 dB(A) and 5.96 dB(A), respectively. The reason for this phenomenon is that the wheel-rail forces increase with the increase in train speed. This study will have important guiding significance and scientific value for the sustainable development of urban rail transit.