中文摘要：

为了分析地铁运营造成的环境低频（〈20 Hz）振动,进行试验室低频振动试验研究。通过试验获得离散频率（5-16 Hz）简谐荷载下隧道内、地表和建筑物内的振动加速度信号,并对其进行预处理和归一化处理,从时程与频谱、加速度级和传递函数3个方面,分析低频振动在隧道结构、地表和建筑物内的传播特征。结果表明：隧道结构低频振动表现为整体振动,地表低频振动以竖向为主,而建筑物内的低频振动以水平方向为主;地表竖向低频振动随着距轨道水平距离的增加而衰减较快,水平低频振动在距轨道0-40 m范围内出现放大,40 m之外衰减较缓;建筑物内的水平低频振动,在10 Hz以下随着楼层的升高而增大,而在10-16 Hz时随着楼层的升高而减小;隧道基底到地表的竖向传递函数值随着距轨道水平距离的增加而逐渐减小,但随频率变化不大,在5-16 Hz范围内的传递函数值为0-0.5。

英文摘要：

Environmental vibrations induced by metro operation have been paid more and more attention, especially the low-frequency （〈20 Hz） vibrations. Low-frequency vibration tests in the laboratory are carried out to obtain the time history of accelerations in the tunnel structure, on the ground and in the surrounding building due to harmonic loads with the discrete frequency range between 5 and 16 Hz. By means of preprocessing and normalizing of the time history of accelerations, the transmission characteristics of low-frequency vibrations in different structures are analyzed from three aspects of time history ＆. frequency spectrum, acceleration level and transfer function. The experimental results indicate that the low-frequency vibration of the tunnel structure performs as a whole, the vertical low-frequency vibration on the ground surface is dominant, and however, the horizontal low-frequency vibration in the adjacent building plays a leading role. The vertical low-frequency vibration attenuates more rapidly with the distance to the track. However, the horizontal vibration amplifies in the range of 0440 m from the track and attenuates slowly beyond 40 m. The horizontal low-frequency vibration in the building increases with the height in the frequencies 0 - 10 Hz, however, decreases in the frequencies 10- 16 Hz, The vertical transfer function values from the tunnel structure to the ground surface decrease gradually with the distance and vary a little with the frequency, and the transfer function values are 0-0. 5 in the frequencies 5-16 Hz.