Proposal of granular material damper using rubber ball with iron core

Abstract

We have investigated the damping mechanism of the granular material damper when a structure having a relatively high natural frequency and small vibration displacement is used as a vibration damping target. In the granular material damper, the motion of the granular material is the basic principle of attenuation occurrence. Focusing on the energy of the granular material damper, the movement of the main system is determined by the energy to be consumed, the energy consumed by the collision of the granular bodies on the left and right container walls and the friction between the granular bodies on the bottom of the container. By using these quantities, it is possible to quantitatively evaluate the damping characteristics of the granular damper. In this research, we studied the high attenuation of the granular material damper by calculation using this evaluation method. We investigated the influence of both Young's modulus and moment of inertia of granular material on damping characteristics. Next, we tested the granular material damper using rubber ball with iron core to verify calculation results.