近斷層地震含速度脈衝之震波，對結構物之危害遠大於同規模遠域地震，本研究針對近斷層載重下，配置雙橢圓鋼板消能器之不同斜撐方向與勁度比，針對其強度、勁度、能量消散、上下樓層位移比分布均勻度等承載性能進行探討。 本研究首先使用有限元素分析配置先前研究使用之消能器於雙層斜撐構架時，結構在近斷層載重下之耐震反應與承載模式，接著取兩組不同消能器進行雙層構架試驗，以驗證有限元素分析之有效性。由試驗與分析比較得知，有限元素分析之構架於近斷層載重下，承載反應與實驗吻合，顯示模型可相當程度預測結構行為；其後為進一步界定雙層構架設計中，適當消能器勁度比值及不同方向斜撐對於結構行為之影響供設計參考，本研究針對不同尺度消能器組合和不同方向斜撐進行有限元素分析與探討；定義構架下層與上層樓層間消能器有效勁度比值為SR，由分析結果可知，在相同近斷層載重加載下，配置適當雙橢圓鋼板消能器勁度比值(SR = 2)之雙層斜撐構架最大強度相較於抗彎構架可提升2.28和2.34倍，初始勁度可達2.13和2.15倍，其累積消能總量則上升2.44和2.5倍，而層間位移分布較抗彎構架更為均勻，上下樓層位移比差異可降低為抗彎構架之0.48和0.92倍，顯示就承載性能而言，配置雙橢圓金屬消能器之斜撐不論方向皆有效提升結構強度和上下樓層位移分布均勻度，然兩種斜撐方向之差異在10%以內，惟配置K型斜撐之構架，其上下樓層位移比之最大差異較小，僅為配置平行斜撐構架之52.2%。 ;Recent studies have shown that near-fault ground motions with velocity pulses pose significantly greater threats to structures compared to far-field earthquakes of the same magnitude. This study investigates the seismic performance of two-story steel frames equipped with double-oval steel plate dampers under near-fault loading. The analysis considers different bracing directions and damper stiffness ratios. Finite element analysis (FEA) was first applied to examine the structural response and load-bearing behavior of a double-story braced steel frame with previously studied energy dissipators under near-fault earthquake loading. Experimental tests on two additional configurations validated the FEA, showing close agreement and confirming its predictive reliability. To establish design guidelines, FEA was extended to various dissipator scales and bracing directions, with the effective interstory stiffness ratio (SR = lower:upper) introduced. Results indicated that frames with an optimal SR of 2 achieved 2.28–2.34 times the strength, 2.13–2.15 times the initial stiffness, and 2.44–2.5 times the cumulative energy dissipation of moment-resisting frames, while exhibiting more uniform displacement distribution. Both bracing orientations improved performance, though K-bracing yielded smaller interstory displacement differences, only 52.2% of those in parallel bracing.
