Top-Story Softening for Enhanced Mitigation of Vortex Shedding-Induced Vibrations in Wind-Excited Tuned Mass Damper Inerter-Equipped Tall Buildings

An Inerter-Based Dynamic Vibration Absorber With Concurrently Enhanced Energy Harvesting and Motion Control Performances Under Broadband Stochastic Excitation Via Inertance Amplification

“…Collectively, the reported data demonstrate that, contrary to the case of EH-TMDI with grounded inerter, the vibration suppression performance of EH-TMDI with non-grounded inerter improves insignificantly with inertance scale up unless a sufficiently low stiffness ratio γs (i.e., flexible connection of the two primary structure masses) is adopted. In this regard, the primary structure softening has a positive influence to the EH-TMDI vibration suppression which is also the case for the TMDI (see Wang and Giaralis 2021). At the same time, EH-TMDI energy harvesting potential increases appreciably with inertance even for non-grounded inerter and primary structure flexibility benefits the rate of this increase with inertance.…”

“…5. In this configuration, the inerter is engaged by the relative dynamics of the two masses which, in turn, depend on the properties of the primary structure and the loading attributes (see also Wang and Giaralis 2021).…”

“…In the parametric investigation, attention is focused on the effects of the 2-DOF primary structure stiffness properties, expressed by the relative stiffness ratio in conjunction with the attributes of the external random loading, namely the correlation and the spectral amplitude ratios ρ and a in Eq.(28). This is because the effects of the damping and secondary mass properties to the EH-TMDI performance have already been thoroughly examined in Section 3, while it has been recently shown that the primary structure stiffness affect significantly the vibration suppression performance of the TMDI in MDOF structures (Wang and Giaralis 2021). In this regard, for all structures considered, the inherent damping properties of the primary structure are taken fixed as ζs,1= ζs,1=5%, the energy harvesting ratio is also taken fixed as ζEH= 10%, the parasitic damping is ζp= 1% and the secondary mass ratio is μΤ= 1%.…”

“…Moreover, the herein paper generalizes the EH-TMDI configuration to treat lumped-mass MDOF primary structures in which the inerter is not grounded. For the latter class of systems, attention is focused on studying the influence stiffness properties of the primary to the EH-TMDI performance, which is known to critically affect the performance of non-regenerative TMDI (Wang and Giaralis 2021), under sets of external random white noise forces with different levels of correlation.…”

Motion Control Performance of Tuned Mass Damper Inerter (Tmdi) in Continuous White-Noise Excited Cantilevered Beams With Various Shapes

“…In recent years the use of the inerter, defined in [1] as a mechanical element that resists relative acceleration through the inertance constant, has been widely considered in various linear passive dynamic vibration absorber configurations for enhanced motion control in dynamically excited structures [2]. Among these absorbers, the tuned mass damper inerter (TMDI) introduced in [3] attracted significant attention in the literature and its potential to achieve improved vibration suppression compared to the standard tuned mass damper (TMD) has been verified in various applications including for the seismic protection of building structures [3][4][5] as well as for safeguarding occupants' comfort in wind excited slender tall buildings [6][7][8]. In the TMDI configuration for building (primary) structures, an inerter is used to link a secondary mass attached to one building floor (commonly the top floor) through a spring in parallel with a viscous damper (dashpot) to a different (lower) floor.…”