Damping in joined friction plates with partially overlapping interfaces

摘要

In this paper, we investigate the damping characteristics for the fundamental and the higher modes in jointed plate structures with partially overlapping interfaces. First, the damping characteristics are experimentally evaluated. Second, the effect of the mode shape on the damping characteristics is examined. Third, the characteristics of energy dissipation due to friction at the interface, which determine the damping characteristics in jointed plates, are analysed. Consequently, we propose a procedure for estimating the energy dissipation at the interface using finite element (FE) analysis. The structure considered in this paper consists of three steel plates bolted together in which a long plate is sandwiched between two short plates. Comparison of the modal damping ratios estimated from the dissipated energy and those measured in modal testing confirms the validity of the proposed estimation procedure. The FE analysis and the experimental results show that the damping characteristics vary depending on the mode, especially for the difference between the symmetric and antisymmetric mode shapes. This is supported by the characteristics of the energy dissipation obtained in the contact analysis of the proposed estimation procedure.