可調式慣質之開發與其抗震之應用

Abstract

本論文聚焦於可調式慣質裝置的實現，及其在建築物抗震方面的應用。慣質是一種兩端點的被動式機械元件，作用力與兩端點相對加速度成正比，因此可以替換傳統質量元件，增加機械網路的設計自由度。而在建築物抗震的應用方面，在樓層間安裝慣質可以改變建築物的震動主頻，以降低地震帶來的損害；若能根據地震特性進行慣質係數的調整，則可進一步強化抗震效果。 研究分成兩大部分。在第一部分提出並實現「爪式」與「桿式」兩種可調式慣質的實現方式，分別搭配滾珠螺桿慣質，前者的慣質係數可以在349.9 kg到1308.9 kg之間作調整，後者則可以在4762.1 kg到9793.5 kg之間進行切換。進一步推導含摩擦力的非線性慣質模型，利用推拉實驗驗證可調式慣質的效果，並與理論模型達到平均93.16%和94.85%的擬合效果。 第二部分則是建築物抗震的實驗，首先使用爪式飛輪慣質搭配縮尺建築物模型，使用「根據不同地震設定最佳慣質檔位」以及「在地震過程中切換慣質檔位」兩種策略進行實驗並比較其效果，前者可以在設定的抗震指標「最大頂樓加速度」J_1、「頂樓加速度和方根」J_2、「最大頂樓相對位移」J_3和「頂樓相對位移和方根」J_4中達成平均22.63%、40.73%、42.36%和58.15%的進步幅度，後者則是可以更進一步增進指標J_1和J_3達平均34.69%和46.60%，顯示地震中切換於建築物抗震方面的潛力。接著使用桿式飛輪慣質搭配全尺寸建築物模型，並使用「根據不同地震設定最佳慣質檔位」的策略進行實驗，能夠在指標J_1、J_2、J_3和J_4中達成平均34.79%、50.46%、23.93%和46.41%的進步幅度，並且後續通過模擬「在地震過程中切換慣質檔位」策略得到43.02%、55.93%、35.99%和49.33%的進步幅度，顯示可調式慣質在全尺寸結構同樣有效果。 上述研究成果，展示可調式慣質裝置的可行性，並驗證可調式慣質在縮尺以及全尺寸建築物模型皆能有效降低地震響應，展現其於抗震領域的應用潛力，可作為未來建築物抗震設計的一種選擇。

This thesis focuses on the realization of tunable inerters and their applications in seismic mitigation of buildings. An inerter is a two-terminal passive mechanical element, where the force is proportional to the relative acceleration between its terminals. Consequently, it can replace traditional mass element and increase the degrees of freedom in mechanical network design. Regarding seismic mitigation, installing inerters between floors can modify a building's natural frequency to reduce seismic damage. Furthermore, adjusting the inertance of the inerter according to earthquake characteristics can further enhance building performance under seismic events. The research consists of two main parts. The first part demonstrates two mechanisms for real-time inertance tuning: the "Claw-type" and the "Rod-type." These were applied to a scaled ball-screw inerter and a full-scale ball-screw inerter, respectively. The inertance of the former can be adjusted between 349.9 kg and 1308.9 kg, while the latter can be switched between 4762.1 kg and 9793.5 kg. We further derived a nonlinear inerter model incorporating friction. Cyclic loading tests were conducted to verify the performance of the tunable inerters, achieving an average experimental-theoretical fit of 93.16% and 94.85%, respectively. The second part involves seismic experiments on building structures. Using the Claw-type inerter on a scaled building model, two strategies were tested and compared: "setting the optimal inertance based on specific earthquakes" and "real-time inertance switching during the earthquake." The former achieved average improvements of 22.63%, 40.73%, 42.36%, and 58.15% in the defined seismic performance indices “Maximum rooftop acceleration” J_1, “Root sum square (RSS) of rooftop acceleration” J_2, “Maximum relative rooftop displacement” J_3, and “RSS of relative rooftop displacement” J_4. The latter strategy further improved indices J_1 and J_3 to averages of 34.69% and 46.60%, demonstrating the potential of real-time switching in seismic mitigation. Subsequently, the Rod-type inerter was applied to a full-scale building model. Using the "optimal inertance setting" strategy, average improvements of 34.79%, 50.46%, 23.93%, and 46.41% were achieved in indices J_1, J_2, J_3, and J_4. Follow-up simulations of the "real-time switching" strategy showed improvements of 43.02%, 55.93%, 35.99%, and 49.33%, indicating that tunable inerters are equally effective in full-scale structures. The results of this study demonstrate the feasibility of tunable inerter devices and verify their effectiveness in reducing seismic responses in both scaled and full-scale building models. This highlights their potential in the field of seismic mitigation and presents them as a viable option for future building seismic design.