Floating slab track with inerter enhanced dynamic vibration absorbers

Abstract

This paper proposes an inerter enhanced dynamic vibration absorber (IDVA) to improve the low-frequency vibration mitigationperformance of the floating slab track (FST). To this aim, the inerter is coupled to a dynamic vibration absorber (DVA) to form the IDVA. Analytical derivations of the FST-IDVA are given. Considering the random property of the wheel-rail interaction, the H2 optimization is performed and closed form solutions for the optimal parameters of the IDVA are obtained. Parametric studies are conducted to evaluate the influences of the inerter on the performances of the FST-IDVA. Numerical simulations are performed to validate the efficiency of the proposed FST-IDVA. Time history analyses of FST, FST-DVA, and FST-IDVA under moving metro vehicle load are computed and compared. When using the FST-DVA, it is found that dynamic responses of the track slab and the force transmitted to the ground are suppressed, but the relative displacement response of the absorber isrelatively large; conversely, when using the FST-IDVA, dynamic responses of the track slab and the force transmitted to the ground are furthersuppressed, more importantly, the relative displacement response of the absorber is mitigated greatly. Overall, the FST-IDVA overperforms the FSTDVA, even the small-mass-ratio absorber is used.