城市轨道交通高架结构振动与声辐射研究

为研究城市轨道交通所引起的高架结构的振动及声辐射水平，采用有限元方法分别建立了连续梁桥的三维振动分析模型及二维声场分析模型，计算了当列车以60km/h的速度通过时桥梁的动力响应及辐射声压。通过频谱分析，声压频谱峰值除在160 Hz附近出现一个明显的峰值外，与振动频谱分布基本相同。相干性分析结果表明，连续梁桥控制90Hz以内的振动，将直接有效的控制辐射声压水平。通过改变桥梁阻尼、支座刚度、行车速度和车辆荷载等参数，计算分析了各参数对结构振动与噪声的影响程度

Vibration and noise influences of elevated structures in urban railway

In order to study the vibration response and radiated noise of elevated structures subjected to moving trains,a 3D vibration model and a 2D sound field model for simply supported girder were established by FEM.The dynamic response and radiated noise of the girder were calculated,with a train running at a velocity of 60km/h.The result shows that the frequency spectra of noise and vibration are similar,except that there is an obvious peak near 160Hz in noise spectrum.The coherence analysis of the spectra shows that,the influence of radiated noise on environment can be effectively controlled by adjusting the vibration components below 90Hz of the girder.The influences of parameters,such as structural damping,support stiffness,vehicle speed and vehicle loading,upon the vibration response and radiated noise were analyzed by changing the parameters.