Analysis of Vibration Propagation Law of Rail Transit Underpassing Large-Span Building Structure

Based on the vehicle-track coupling dynamics theory and finite element analysis method, the coupled vibration analysis model of the railway transit underpass the terminal structure is established, and the vibration propagation law of the soil and the upper terminal structure under the condition of the subway train underpass is analyzed. The results show that, compared with the low-frequency vibration, the vibration attenuation of the medium-high frequency around 63 Hz is more significant; The common column-net between tunnel structure and superstructure will lead to direct vibration transmission, and the structural design of rail transit underpass buildings should consider avoiding the common column-net. In the transmission of train vibration to superstructure and surrounding soils, the attenuation of floor vibration and soil vibration shows periodic attenuation regularity with the increase of distance from the line, and the attenuation of building vibration is obvious. The attenuation speed of soil is obviously less than that of soil. The isolation of building structure and vibration source should be given priority in vibration isolation design.