Application and optimization design of non-obstructive particle damping-phononic crystal vibration isolator in viaduct structure-borne noise reduction

The problems associated with vibrations of viaducts and low-frequency structural noise radiation caused by train excitation continue to increase in importance. A new floating-slab track vibration isolator-non-obstructive particle damping-phononic crystal vibration isolator is proposed herein, which uses the particle damping vibration absorption technology and bandgap vibration control theory. The vibration reduction performance of the NOPD-PCVI was analyzed from the perspective of vibration control. The paper explores the structure-borne noise reduction performance of the NOPD-PCVIs installed on different bridge structures under varying service conditions encountered in practical engineering applications. The load transferred to the bridge is obtained from a coupled train-FST-bridge analytical model considering the different structural parameters of bridges. The vibration responses are obtained using the finite element method, while the structural noise radiation is simulated using the frequency-domain boundary element method. Using the particle swarm optimization algorithm, the parameters of the NOPD-PCVI are optimized so that its frequency bandgap matches the dominant bridge structural noise frequency range. The noise reduction performance of the NOPD-PCVIs is compared to the steel-spring isolation under different service conditions.