高速铁路桥梁振动噪声影响参数研究

Research on the Influence Parameters of Vibration and Noise of High-speed Railway Bridge

为了探究桥梁结构的振动噪声,以24 m简支箱梁为研究对象进行车桥耦合动力分析,求解轨道不平顺作用下的竖向轮轨力。利用有限元与边界元结合方法,建立桥梁结构声场分析模型,此模型将竖向轮轨力作为激励,以桥梁结构的动力响应作为边界条件,分析噪声声压级的频率分布特性和传播规律。研究表明,桥梁结构噪声最大值位于列车加载位置附近,声波能量由桥梁结构向外部空间辐射,其频段主要在100 Hz以下,分布于桥梁结构正上方与正下方。桥梁结构噪声在传播过程中,其衰减性随着传播距离增大而逐渐增加;噪声声压随车辆速度增加而增大,随桥梁刚度和腹板厚度的增大而减小。

In order to explore the vibration and noise of the bridge structure,this paper took 24 m simply supported box girder as the research object to carry out vehicle-bridge coupling dynamic analysis,and solved the vertical wheel-rail force under the effect of track irregularity.Then,the method of combining finite element and boundary element was used to establish the sound field analysis model of bridge structure.This model takes the vertical wheel-rail force as the excitation and the dynamic response of bridge structure as the boundary condition to analyze the frequency distribution characteristics and propagation law of the noise sound pressure level.The research shows that the maximum noise of the bridge structure is located near the loading position of the train,and the acoustic energy radiates from the bridge structure to the external space,and its frequency band is mainly below 100 Hz,distributed directly above and below the bridge structure.In the process of the propagation of bridge structure noise,its attenuation gradually increases as the propagation distance increases.With the increase of vehicle speed,the noise pressure increases,while the increase of bridge stiffness and plate thickness makes the noise pressure smaller.