【Objective】 Because the structural vibration in rail transit has a deep impact on safety and environment, in order to control the vibration of the plate structure,【Method】the amplitude-enhanced device can be used to increase the stiffness and mass of the vibration absorber, and the amplitude-enhanced vibration absorber is periodically arranged on the plate. Based on the null space method and the energy method, a new band gap calculation method is improved, which overcomes the difficulty of constructing the shape function under the periodic boundary condition, and greatly improves the calculation efficiency. Based on this method, the band gap characteristics of the periodic layout amplitude enhanced type are obtained, and the vibration mode law of the starting and ending points of the band gap is studied. In addition, the influence of the amplification coefficient and mass ratio of the amplitude enhancement device on the band gap is analyzed. The vibration transmissibility of periodic plate structure with amplitude enhanced vibration absorber and ordinary vibration absorber is compared and analyzed.【Result】The results show that the low-frequency vibration reduction effect of the device can be effectively enhanced by selecting the appropriate amplification coefficient and mass ratio of the amplitude-enhanced vibration absorber. The amplitude-enhanced vibration absorber has the effect of increasing the attenuation and broadening the attenuation range.【Conclusion】The amplitude enhancement device has a good effect on the specific frequency vibration control of the periodically arranged plate structure. The research results of this paper can provide a theoretical basis for vibration and noise reduction in the field of rail transit in the future.