Optimal design of inerter‐based nonpacked particle damper considering particle rolling

Abstract

AbstractThis paper presents an optimal design method for a nonpacked particle damper (NPPD) based on a simplified mechanical model and corresponding damping mechanism analysis. First, an equivalent inertial single‐particle mechanics model (EISM) and the corresponding equivalent principle were proposed to consider the influence of particle rolling on the vibration reduction. The experimental verification of the EISM under seismic ground motion was subsequently carried out. Based on a reasonable verification of the proposed model, an analytical solution of the EISM single‐degree‐of‐freedom structure system for the symmetric two‐impacts‐per‐cycle motion was obtained. The influence analyses of collision distance on the damping effect and the damping mechanism under resonance and nonresonance harmonic excitation were performed. The theoretical calculation formula for the optimal collision distance for energy consumption was obtained based on the damping mechanism analysis. Finally, numerical simulations under harmonic excitation and seismic ground motion were carried out to verify the rationality and generalization of the proposed optimal collision distance. Accordingly, an optimal design method for the NPPD was proposed. Based on the proposed optimization method, the vibration reduction effect of NPPD under far‐field records, near‐fault pulse‐like records, and near‐fault nonpulse records are discussed. The analysis results show that the vibration reduction effect of the NPPD is affected by the response frequency of the uncontrolled structure. The proposed optimization method can be used as the basis for the optimization of NPPD under earthquakes.