Experimental Study on the Damping Effects of Various Vibration Reduction Measures

Field measurements are the most effective and direct way to evaluate the effects of vibration reduction measures. Through field measurements, this study examined the actual damping effects and vibration transfer characteristics of five vibration reduction measures for subway systems, namely, steel spring floating slabs, resilient short crossties, double- layer nonlinear damping fasteners, Vanguard fasteners and rubber floating slabs. The vibration level and 1/3 octave frequency division vibration level was used as vibration evaluation indices for analysis. This study aimed to provide a reference for the actual damping effects of vibration reduction measures. The results show the following: steel spring floating slabs outperformed resilient short crossties by 23.2 dB. Double-layer nonlinear damping fasteners outperformed Vanguard fasteners and rubber floating slabs by 1.6 and 2 dB, respectively. Resilient short crossties, Vanguard fasteners and double-layer nonlinear damping fasteners were effective in reducing vibration from steel rails to track beds (floating slabs). Steel spring floating slabs and rubber floating slabs were effective in reducing vibration from track beds (floating slabs) to tunnel walls.