Noise Radiation from Concrete Box Girders Generated by a High-Speed Train Running Along a Track-Bridge System as an Infinitely Long Periodic Structure

摘要

Bridges with concrete box girders are widely used on China's high-speed railways. Although the bridge structure has a high global static stiffness, its natural frequencies are still low due to the wall-shaped structure, raising concerns about low frequency noise radiation. An effective approach to addressing these concerns is to predict bridge vibration and noise radiation by establishing a dynamic-acoustic vehicle-track-viaduct model. This is the topic of this paper. The dynamics of the vehicle-track-viaduct system is modeled in the frequency domain based on the periodic structure theory and the Fourier-series approach. Predicted vibrations of all the box girders are decomposed into propagating waves, so that sound radiation from the box girders can be predicted using the 2.5D acoustic boundary element method. Comparison between prediction and measurement is performed, confirming the usefulness of the model. The model is then used to study noise radiation from the concrete box girders as a high-speed train passes.