Vibration attenuation performance of isolator based on locally resonant phononic crystal via train load

A locally resonant phononic crystal isolator (LRPCI) that the external ring vibrators attached to the central connectors through the rubber is designed, and it is installed to attenuate vibration under the track of rail transit. The energy band structure of the isolator is calculated by the finite element method, and its bandgap range is from 49.7 Hz to 104.9 Hz. The transmission loss and the equivalent mass density are further calculated to verify the accuracy of the bandgap, and they are perfectly corresponding to the bandgap. Then, the vehicle-rail-floating slab track-tunnel multibody dynamic model is built to analyse the vibration attenuation performance of the floating slab track installed the LRPCI and steel spring isolator under the train load. The results show that the LRPCI has a low frequency bandgap and can reduce the low frequency vibration, and the vibration isolation performance of the LRPCI is better than that of the steel spring isolator. The LRPCI has a low frequency bandgap, which can isolate the vibrations caused by wheel-rail interaction, and further reduce the impact of vibrations on surrounding buildings and the environment.