高い固有振動数を有する構造物における粒状体ダンパの減衰メカニズム（相対運動質量および回転運動質量の提案とそれらを用いた考察）

抄録

We investigated the damping mechanism of a granular material damping system applied to reducing vibration in structures that have a high natural frequency and small vibration displacement. Experiments were conducted under several conditions of total mass of granules. We also constructed a computational model of a single-degree-of-freedom vibration system with a granular material damper to study the mechanism of a granular material damping system. On the basis of the fundamental idea that the damping effect of a granular material damper is governed by the motion of the granules, we classified the granular materials as “relative motion mass” and “equivalent added mass” in the translational motion and as “rotating mass” and “not rotating mass” in the rotational motion and then considered the relationship of these mass classes to the damping characteristics. In this report, we examine the relationships of the motion of the granular materials, “relative motion mass” and “rotating mass”, and damping ratio by means of experiments and calculations for structures that have a high natural frequency and small vibration displacement.