Vibration Performance in Frequency Domain of CRTS I Double-Block Ballastless Track

According to the structural characteristics of the double-block track, using the Green’s function and superposition principle, the analytical model of the vertical vibration of the double-block track in frequency domain was established to analyze the responses of the double-block track in frequency domain and the influences of fastener stiffness, bedplate thickness and subgrade supporting stiffness on it. The results show that there are three obvious peaks for the rail mobility which are caused by bedplate resonance (35 Hz), rail resonance (200 Hz) and pinned-pinned resonance (1 kHz). Within the frequency range of less than 35 Hz, the bedplate mobility is determined by the bedplate supporting stiffness. Also the bedplate vibration decay rate increases with the increasing frequency. The bedplate resonance and wheel-rail coupling resonance have the most significant effect on the bedplate displacement. The frequency range where the rail high vibration decay rate lies gets wider with the larger fastener stiffness. Increasing the bedplate mass cannot attenuate its vibration in the mid-high frequency range.