Abstract:Vibrations generated by subway train operations have the potential to adversely affect the normal use of precision instruments within laboratories. In order to analyze the current state of vibration response at a laboratory site proposed to be built along the subway line, a study was conducted to test environmental vibrations and train-induced vibrations at the site. An integrated seismograph was used to verify the accuracy of conventional velocity sensors at low frequencies. The results indicate that the 941B velocity sensor demonstrates good accuracy for frequency bands above 0.6 Hz, which meets the vibration measurement and evaluation standards based on VC vibration criteria. When considering the comprehensive impact of environmental vibrations within a determined period, the current site's vibrations are at a relatively low level, essentially satisfying the vibration requirements for most general-purpose equipment and the vast majority of precision instruments. Moreover, the ambient vibrations can significantly increase under the influence of certain instantaneous external vibration sources, but these effects are mostly within the 10 Hz or higher frequency bands. When a subway train passes, there is an increase in vibrational energy near 50 Hz, which is relatively favorable for passive vibration isolation.