| 摘要: | 本研究採用雙向耦合離散元素法(Discrete Element Method, DEM)與有限元素法(Finite Element Method, FEM)模擬技術，建立五層樓鋼架結構模型，並在鋼架結構頂樓處安裝顆粒阻尼器(Particle Damper, PD)，探討在不同顆粒材料、顆粒粒徑、顆粒填充率、及腔體設計下，顆粒阻尼器對於鋼架結構系統之減振效益，並導入「洛馬普里塔地震」(1989 Loma Prieta earthquake)地表加速度歷時曲線，分析含顆粒阻尼器鋼架結構系統在實際地震波源下之動態反應。本研究設計「懸臂樑自由振動試驗」與「鋼珠撞擊平板試驗」兩項基準測試，驗證本研究建立之雙向耦合DEM-FEM模型的合理性與正確性，研究結果顯示: (1)在相同顆粒總數量下，填充密度較大之顆粒，其碰撞接觸力較大，碰撞耗能較大，減振效果愈佳；(2)在相同顆粒總質量下，填充粒徑較小之顆粒可增加顆粒-腔體間接觸面積及碰撞機率，進而增加減振效益；(3)隨著顆粒填充率降低，其減振效果也逐漸降低，說明本研究設計之顆粒阻尼器需較大顆粒填充率以增加顆粒-腔體間接觸碰撞機率；(4)在腔體總體積與填充顆粒總質量皆相同情況下，將單一腔體劃分為數個小腔體可提高顆粒-腔體間接觸碰撞機率，進而增加減振效益；(5)在真實地震波源振盪下，在系統前三模態特徵頻率下皆有優異減振效果，同時在水平雙向振盪下亦有良好減振效益，成功驗證顆粒阻尼器具有寬頻減振特性與多向性減振特性。;This study uses two-way coupling discrete element method (DEM) and finite element method (FEM) simulation technology to establish a five-story steel frame structure model, which includes a particle damper on the top floor of the steel frame structure, discussing the vibration damping behavior of particle damper for steel frame structural system under different particle materials, particle sizes, filling ratios, and cavity designs. Further more, introducing the "Loma Prieta Earthquake, 1989" surface acceleration duration curve to analyze the dynamic response of steel frame structural system containing particle damper under actual earthquake wave source. In order to verify the correctness of the simulation results of the two-way coupled DEM-FEM model established in this study, two benchmark tests, "cantilever beam free vibration test" and "steel ball impact plate test", were designed. The research results show that: (1) Under the same total number of particles, particles with a higher material density will have larger contact forces, greater energy consumption, and better vibration damping effects. (2) Under the same total mass of particles, filling particles with smaller particle size can increase the contact area and contact probability between the particles and the cavity, therefore improving the vibration damping effect. (3) As the particle filling ratio decreases, the vibration damping effect also gradually decreases, indicating that the particle damper designed in this study requires a larger particle filling ratio to increase the probability of contact and collision between the particles and the cavity. (4) Under the same total volume of the cavity and the same total mass of the filled particles, divide a single cavity into several small cavities can increase the probability of contact and collision between particles and cavity, therefore improving the vibration damping effect. (5) Under real seismic wave source oscillations, the system has outstanding vibration damping effects at the first three mode characteristic frequencies, and also shows outstanding vibration damping effects under multi-directional oscillations. It has been successfully verified that the particle damper has broadband vibration damping characteristics and multi-directionality vibration damping characteristics. |
