At present, there is no systematic study on the transfer characteristic of stratum vibration induced by metro operations. The stratum vibration transfer characteristic tests were performed in a lab. of track vibration abatement & control by using an automatic falling weight system to impact an underground track inside a tunnel. The propagation attenuation characteristics of vibration accelerations in the stratum were studied in a frequency range of 0 ~ 200 Hz. The results indicated that ① the attenuation rate of the acceleration peak value from the tunnel to the ground surface can reach 81.25% and the strata have a strong attenuation function; ② the transfer function amplitude of the vibration responses from the tunnel to the ground surface is less than 0.4, except that the transfer function amplitude is greater than 1 near 30Hz frequency band; ③ 1/3 octave acceleration level transmission loss curve from the tunnel to the ground surface reveals a V-shape distribution, the transmission loss is the least near 30Hz and is a negative value at this frequency band; the vibration acceleration energy from the tunnel to the ground surface is amplified.%目前,对于地铁运营引起的振动在地层中的传递特性一直未有系统深入的研究.利用自动落锤激励装置锤击轨道减振与控制实验室10 m埋深隧道内轨道,研究了0～200 Hz频段振动加速度在地层中的传播衰减特性.试验结果表明:①隧道结构-地面振动加速度峰值衰减率达到81.25％,地层对振动有很强的衰减作用.②除了30 Hz附近频段传递函数幅值大于1,隧道结构到地面振动响应传递函数幅值普遍小于0.4.③隧道结构-地面1/3倍频程加速度级传递损失曲线呈V形分布,传递损失在30 Hz附近最小,且为负值,此频段振动加速度能量从隧道传递到地面有放大现象.
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