The granular material damper performs vibration reduction by converting the kinetic-energy that control on vibration object vibrates into thermal energy occurring by impact with the friction mark between the particle and the control on vibration object. Because the mechanism is simple, advantages include ease of the installation. On the other hand, it is difficult to predict the control on vibration performance by the characteristics of the particle to enclose and discontinuous vibration behavior. Therefore this research predicted the attenuation performance from simulation of the particle behavior using the discrete element method about the control on vibration of the granular material damper of the slight infinitesimal grain which paid its attention to basic particle size of the microsize.
