Dynamic response and vibration reduction performance analysis of three-dimensional floating slab track

Floating slab tracks (FSTs) have been increasingly used to reduce the impact of vibration on precision instruments and historical relics along metro lines. However, it is crucial to achieve optimal vibration reduction design by reasonably configuring the parameters of the FST. To systematically investigate the dynamic response characteristics of three-dimensional FST under harmonic loads and address the problem of unclear quantitative influence of key parameters on the vibration reduction performance of FST. A model for solving the dynamic response of a three-dimensional FST under fixed harmonic loads in the frequency-wavenumber domain was established in this study. The dynamic response of the FST was studied by utilizing the frequency response function (FRF) and isolator force transmission rate. The effects of several factors on the vibration reduction performance of FSTs were studied, including lateral and longitudinal spacing of isolators, stiffness and damping of rail fasteners and isolators, and different parameters of double-row isolators. The results indicate that the displacement FRF decays by 74.3% from the right to left rail. The longitudinal spacing of isolators has a significant impact on the vibration reduction capability of the FST; the effect of lateral spacing is small. The increase in damping and stiffness of the isolator resulted in a 26.5% reduction and a 72% increase in the force transmission rate of the isolator, respectively. The performance of the isolator on one side of the FST decreases by 50% that can cause the force transmission rate to increase by 100% and can damage the long-term performance of the FST. The results can improve the scientific configuration of FST parameters and provide clear suggestions for the vibration reduction design of FSTs.