柱子是重要結構構件，大地震中一樓柱承擔軸向以及彎矩荷重，可能會發生柱底挫屈且進而衍生受軸壓力產生軸向變形，留下殘餘變形，震損修復程序中由於底層柱荷重以及挫曲變形特性使得修復過程較其他結構構件複雜。近十幾年鋼構柱腳接頭的改良研究中，具自復位特性的柱腳接頭透過軸向預力構件以及阻尼裝置接合柱構件與基礎梁，在受彎過程中柱與基礎梁接觸界面開啟，並在力量消散後透過連接構件中的軸向拉力提供回復彎矩閉合構件開啟界面，可以達到零殘餘變形的目的。且過程中僅阻尼裝置進入塑性行為並且消耗能量，地震後替換阻尼裝置便可以恢復接頭的性能。
本研究提出針對箱型柱的新型的含束制型消能鋼棒自復位柱腳，以內柱負擔軸向預力外柱負擔軸向以及彎矩荷重的系統解決傳統自復位柱腳中柱構件同時承受上部載重與預力的問題，並且以消能鋼棒連接底板與基礎梁方式減少阻尼裝置過於突出柱面所造成的裝修問題。
根據足尺反覆加載實驗結果驗證本文提出的自復位柱腳能夠提供穩定的自復位遲滯迴圈，柱腳整體零殘餘變形、塑性消能集中在可替換阻尼裝置，且柱構件全程保持彈性。數值分析結果顯示，中低樓層於一樓採用自復位柱腳相較於固定基礎樓層殘餘層間轉角下降80%。本文提出的計算模型，在無局部塑性變形的情況下理論遲滯迴圈在各階段勁度、解壓彎矩以及目標層間轉角彎矩值等與試驗結果相近，可作為本文自復位柱腳接頭設計應用時力學行為之參考。

This study proposed a new type of steel box column base with self-centering behavior to solve the problems often encountered in practical use. The column base consists of an inner and an outer box column. The former one is adopted to sustain the required post-tension force, and the latter one is a structural column that must sustain vertical and flexural loads. The two-column system decouples the problem of the additional axial post-tension load acting on the structural column. Plastic deformation would concentrate on steel rod dampers adopted at the base. These dampers could be replaced after an earthquake event. Full-scale cyclic test experiments were conducted to verify the performance. The results indicated that the connection exhibited stable self-centering behavior and the characteristics of zero residual deformation. Energy dissipation is concentrated in the replaceable damping device, and the column member maintains elasticity in the test. In addition, numerical analysis results demonstrated that the first-floor residual story drift of three-story and six-story buildings using a self-centering column base is reduced by 80% compared with those of the fixed foundation buildings. Moreover, the proposed theoretical model matches the experimental results in terms of stiffness, decompression moment, and target moment at each stage, which can be used as a reference for mechanical behavior in design and application.

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