高速铁路桥梁结构振动、噪声与环境振动现场试验

Field Test on Structural Vibration,Noise and Environmental Vibration of High-speed Railway Bridges

为探讨高速铁路桥梁结构振动与噪声产生机理和传播规律,选择沪昆高铁高安—南昌区间某铁路桥梁,对高速列车通过时引起的桥梁结构振动、环境噪声和大地振动进行现场测试。结果表明:高速列车诱发桥梁结构振动的优势频率为31.5~125.0 Hz,峰值频率为31.5~63.0 Hz;在0~50 Hz频率范围,桥梁顶板振动>两翼振动>底板振动>腹板振动;在大于50 Hz频率范围,桥梁顶板振动>底板振动>腹板振动>两翼振动;高速列车通过桥梁时,紧邻桥梁的噪声测点声压级峰值频率为80~160 Hz,远离桥梁的噪声测点声压级峰值频率为800~1250 Hz;距离桥梁外轨30 m的断面处,主要噪声源为轮轨噪声、空气动力噪声和受电弓噪声,最大声压级均大于70 dB(A),超过声环境限值;高速铁路车-桥耦合振动引起的大地横向和垂向振动的优势频率为20~63 Hz;在距离桥梁中心线20 m以外范围,高速列车通过桥梁时引起的大地振动低于城市区域环境振动标准65 dB。

In order to investigate the mechanism and propagation law of structural vibration and noise of high-speed railway bridges,a railway bridge between Gao’an and Nanchang of Shanghai—Kunming high-speed railway was selected to measure the bridge structure vibration,environmental noise and ground vibration caused by high-speed trains passing through.The field tests show that the dominant frequency of the vibration of bridge structure induced by high-speed train is 31.5~125.0 Hz,with the peak frequency of 31.5~63.0 Hz.In the frequency range of 0~50 Hz,the vibration of the bridge top plate is the greatest,followed by the vibration of the two wings,the vibration of the bottom plate and the vibration of the web plate,while in the frequency range greater than 50 Hz,the vibration of the bridge top plate is the greatest,followed by the vibration of the bottom plate,the vibration of the web plate and the vibration of the two wings.When a high-speed train passes a bridge,the peak frequency of sound pressure level is 80~160 Hz at the noise measuring point close to the bridge,and 800~1250 Hz at the noise measuring point far away from the bridge.At the cross section 30 m from the outer rail of the bridge,the main noise sources are wheel-rail noise,aerodynamic noise and pantograph noise,with the maximum sound pressure levels of the measuring points all above 70 dB(A),exceeding the limit of sound environment.The dominant frequency of the lateral and vertical ground vibrations caused by the vehicle-bridge coupling vibration of high-speed railway is 20~63 Hz.When the distance from the center line of the bridge is greater than 20 m,the ground vibration caused by the high-speed train passing through the bridge is lower than 65 dB of the standard limit for environmental vibration in urban areas.