论文部分内容阅读
选取上海某实际场地,开展地铁运行引发的场地振动实测。基于实测加速度响应信号,首先采用传统方法获得了信号在时域和频域内的能量分布特点,总结出场地振动水平随与振源距离增加而衰减的规律及振动频率的主要分布范围。其次,采用Mexican hat小波对信号进行连续小波变换,分析了信号时-频能量谱及时-频累积能量的分布特点,揭示出地铁自身的编组形式是造成振动非平稳性的直接原因,且地铁行进过程中列车对场地多数测点振动响应的影响范围主要集中于穿越测试断面的本节车厢及前方一节车厢,但在振动能量放大区,列车的影响范围基本仅限于穿越测试断面的本节车厢。
Select a real site in Shanghai to carry out the subway vibration caused by the actual test site. Based on the measured acceleration response signal, the energy distribution characteristics of the signal in the time and frequency domains are obtained by the traditional method. The law of the attenuation of the site vibration level with the increase of the vibration source distance and the main distribution range of the vibration frequency are summarized. Secondly, Mexican hat wavelet is used to carry out continuous wavelet transform to analyze the distribution characteristics of the time-frequency energy spectrum and time-frequency cumulative energy. It is revealed that the formation of the metro itself is the direct cause of vibration non-stationarity, During the process, the influence range of the train on the vibration response of most measuring points of the site is mainly concentrated on the carriages passing through the test section and the carriages in the front section. However, in the vibration energy enlarging area, the influence range of the trains is basically limited to the carriages traversing the test section .