Research on vibration monitoring and vibration control of buildings near subways

Abstract. With the acceleration of urbanization, urban subway networks have become increasingly dense. Subway operations generate significant vibrations and noise, which are transmitted through tunnels, foundations and bases into interiors of buildings. It reduces the serviceability and comfort level of buildings. Field monitoring and data analysis were conducted on several sites of buildings during construction, revealing notable impacts from both vibrations and noise. Analysis and summary of subway vibration characteristics and propagation features within buildings indicate that subway vibrations possess wide frequency bands, small amplitudes, and are predominantly vertical in nature. Within buildings, the high-frequency components of subway vibrations attenuate rapidly along the floors, while the mid-to-low-frequency components, which are similar to the dominant frequencies of structure, attenuate slowly or even amplify. To mitigate the impact of subway vibrations, three approaches could be adopted: vibration control at the source, vibration control along the external transmission path of buildings and vibration isolation bearings within structures. Taking a kindergarten project in Shanghai as background, steel spring vibration isolation bearings were utilized in the subway vibration isolation design. The design resulted in a reduction of up to 14dB in the maximum vibration acceleration level of superstructure and a reduction of up to 19dB in the maximum secondary radiated noise of superstructure, demonstrating a significant effect of vibration control. The design could provide valuable references for related projects.