Research Of Structure-borne Noise Of 30m Concrete Simple Supported Box Girder In Urban Rail Transit Viaduct

Since the 21 st century, the traffic congestion problem in the city has become the key and one of the hot spot issue in major cities. In order to ensure the rapid transport in city, urban rail transit developed fast in whole country which brings vibration and noise problems to surrounding buildings and public by train through downtown. Becouse of the high cost of renovation and reconstruction of rail transit and the wide range of noise issue affecting crowds, the noise problem of urban rail transit got more and more attention.This paper reviewed the acoustic properties and current research of structure soise of the bridge, then introduced the the existing evaluation methods and physical parameters of noise, pointing out that using the existing structure of the noise assessment method has some limitations.In this paper, a domestic urban rail transit viaduct vibration and noise tests conducted to obtain bridge noise attenuation with distance relationship. By using the shield effect of the fully enclosed sound barrier, the noise measured under the box girder is considered as the structure soise of the bridge. The sound barrier has been proved as a effective way to control the noise of urban rail transit viaduct.Based on FEM-BEM theory and moving mass model, this paper uses a 30 m simple box girder model which commonly used in urban rail transit to calculate the structure noise of viaduct. First, the vibration and radiation noise of bridge has been calculated and analysised, the analyzes this two factors in time domain and frequency domain, finally get the relation between vibration and noise, and the regularity of their transmission and attenuation, the calculation value and the measured value of the vibration and noise are also constrasted each other to check the accuracy of the calculation model. Dynamic analysis of bridge is calculated by ANSYS, while radiation noise is calculated by the transient acoustic BEM module of Virtual.Lab Acoustics.This papar analyzes the variation of vibration and radiation noise caused by bridges and vehicles through changing the parameters of bridges and the speed of vehicles, which provides a theoretical basis for vibration and noise reduction in the engineering practice.