An efficient frequency domain analysis method for bridge structure-borne noise prediction under train load and its application in noise reduction

Abstract

Development of an efficient method for solving the structure-borne noise of the bridge in the frequency domain is of concern. Based on the stochastic theory, the vehicle-track coupling model is established in the frequency domain, and its frequency domain response and the force transmitted to the bridge are analyzed by the pseudo excitation method-symplectic method (PEM-SM). Thereafter, the field vibration and noise test of a 30 m U-shaped concrete subway girder are carried out to compare the cases before and after installing damping fasteners. In the frequency domain, after the input of the force transmitted to the bridge, the finite element–boundary element method (FE-BEM) model of the girder is developed to predict the vibration and structure-borne noise. There is a rationally good agreement between the results of numerical simulations and those of experiment, suggesting an innovative idea for the rapid prediction of structural vibration and noise. Finally, the noise reduction effect and mechanism of the acoustic board and steel spring floating plate beneath the track are discussed. The obtained results reveal that reducing the input of the track system to the bridge is better than preventing the vibration and noise radiation of bridge plates. The above results provide a theoretical and experimental basis for calculating and controlling of vibration and noise in rail transit.