About the author:

The Sixth Engineering Co., Ltd. of China Railway 20th Bureau Group Co., Ltd., Xi’an, Shaanxi 710032, China

Abstract:

Taking the development project over a subway line in Chongqing as the background, this studyestablished a mechanical model of train,track interaction and a finite element model incorporating tunnelsand soil based on the vehicle,track coupled dynamics theory. By combining field measurement data, thevibration characteristics （with a dominant frequency concentrated at 63Hz） and secondary noisepropagation patterns in the TOD building cluster caused by subway operations were analyzed. Thefindings indicate that the vibration levels in the leasing area, due to its proximity to the tracks, exceedednational standard limits. To address this,vibration and noise reduction measures were proposed thatreplacing conventional fastenings with elastic fastenings in the depot and throat areas, installing springvibration isolation bearings in the office building area above the throat section, and adding vibrationisolation pads to the side walls of leased residential units. After implementation, the vibration andsecondary noise indicators in all functional zones fell within the national standard range. The maximum Z,weighted vibration level attenuation reached 4 —— 8.9dB（A），while the maximum sound pressure levelattenuation achieved 6.2 —— 9.6dB（A）， demonstrating that the vibration and secondary noise mitigationmeasures adopted in the project effectively controlled both vibration and structural secondary noise.