本研究為探討不同箍筋形式下，T頭機械式錨定於鋼筋混凝土梁柱接頭之錨定行為及破壞模式，依據ACI 318-14 [6]及ACI 352R-02 [5]規範設計三座卜字梁柱接頭試體進行反覆載重試驗。試體採用SD420W鋼筋與28Mpa之常重混凝土，箍筋分別採用傳統剪力箍筋與連續矩形箍筋，標準彎鉤與T頭機械式錨定之設計伸展長度分別為18.18 db及15.91 db。試驗於台南國家地震中心之雙軸向動態試驗系統(bi-axial testing system, BATS)進行，試驗載重設計以0.1Agfc’ (440kN)軸向力下進行最大達10%層間變位角之側位移，以模擬鋼筋混凝土韌性構架於地震力作用下之行為，並探討不同錨定形式對鋼筋混凝土構件之耐震性能影響。
　　試驗結果顯示，標準彎鉤錨定與T頭機械式錨定於錨定性能上相當，三座試體於柱體皆能於預測塑鉸區產生撓曲裂縫並發展成塑鉸，此外，比較不同試體之位移韌性比能發現，使用T頭機械式錨定對梁柱接頭之韌性性能有顯著的提升，相較於標準彎鉤錨定試驗之總能量消散亦高出20%。據此，能說明T頭機械式錨定之錨定效果與標準彎鉤錨定相當，甚至更佳，於反覆載重下T頭機械式錨定試體亦表現出更佳之韌性行為，並且於工程實務上有更佳的施工性，於經濟上亦更具有經濟效益。

The used of hook anchorage often cause steel congestion in member joints of the building. From previous study of beam-column joints, mechanical anchorages provide a promising solution for steel congestion in joints. Results of an experimental program on the cyclic response of footing joints using diffident types of transverse reinforcement specifically conventional stirrups and continuous spiral are presented, in order to evaluate the used of mechanical anchorages. Three footing joints specimens were tested under cyclic loading with consistent gravity load equal to 440 kN(0.1Agf’c), to simulate the gravity loads and earthquake loads. Key variables included different anchorage methods and transverse reinforcement configuration. The presented experimental program shows that specimens exhibited side-face concrete blowout, back concrete pushout, or a combination of two failure modes. All specimens underwent plastic hinging while no bar slip was observed, which demonstrate that the design of developed length based on ACI 318-14 and ACI 352R-02 provide an appropriate estimate of anchorage strength. Specimen with mechanical anchorage performed better ductility and energy dissipation. A comparison of the strain at the anchorages shows that mechanical anchorages can exhibit adequate anchorage capability and satisfactory performance while behaving different tensile force transference.

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