1994年美國北嶺地震後，震損調查發現許多鋼構建築物的梁柱接頭發生下翼板熱影響區開裂脆性破壞，由於台灣早期的鋼構建築採用與美國相近的梁柱接頭接合型式，因此未來若台灣發生地震，很有可能發生此類破壞。目前國內外許多研究提出了針對此類型接頭的補強的方式，但是對於事先未補強而受到震損的接頭修復補強方式很少有相關研究，同時考量到補強多動用到現場銲接鋼板及火焰切割等施工方式，對於附近有管線通過或是對於煙塵敏感的空間，此類方式則有施作上的困難。
本研究針對此類破壞提出不需要現場銲以及切割的新型修復方法，並且提出強度計算方式，設計一組傳統非韌性接頭，對其進行靜態反覆加載實驗探討其破壞模式，接著將破壞接頭進行修復後再次加載，比較破壞前後接頭性能差異。由實尺寸實驗結果重點如下:
1. 傳統接頭由過去文獻與調查研究指出易發生扇孔附近熱影響區域的脆性破壞，本研究中的兩組試體亦發生相同的破壞模式，同時在半圓形扇孔底部發現應變高度集中狀況，因此接頭應注意避免使用此類型的扇孔。
2. 性能方面傳統接頭於層間變位角2%皆發生下翼板斷裂破壞，修復後接頭可加載至層間變位角4%無發生明顯損壞，且未有明顯的強度衰減。修復後接頭可恢復至原先接頭強度85%並增加一倍耗能，韌性大幅提升，但由於鋼板滑動等原因，修復後接頭的初始勁度較原先接頭的低。
3. 本研究依照其受力行為推導修復構件設計方式計算結果相比實驗數據約減少5%~10%，設計偏保守，可供實務應用參考。

Weld Unreinforced Flange-Bolted web (WUF-B) connection has been proved as a brittle type beam to column connection in the 1994 Northridge earthquake. Many seismic enhance methods have been proposed since the earthquake event. Most of them need to weld a new plate or cutting in the field. This research proposes a field weld free seismic-repair method for the seismic damaged WUF-B connection. A full-scale experiment was conducted to evaluate the effectiveness of steel plate surrounded method. The method used steel plates to repair destructive traditional steel moment-resisting connection, for screwing steel plates at bottom flange and let steel plates clamp the moment connection. The experiment indicated that traditional joint occurred brittle fracture near the weld access hole for bottom flange slitted, and the story drift ratio of traditional joint can’t exceed 2%. Repaired joint can develop to story drift ratio about 4% without moment strength decline and didn`t see any damage simultaneously, and dissipation of energy increase one times than traditional joint, but the stiffness of retrofit joint can’t recover to original beam column connection, because of slipping occur between steel plates and joint. This research proposes the design method of the repair component according to the force behavior of the joint, and the calculated strength is roughly consistent with the experimental results, which can be used as a reference for practical applications.

[1] 陳純森, 鋼結構工程實務(第五版), 科技圖書, 2019.
[2] FEMA, FEMA352-Recommended Postearthquake Evaluation and Repair Criteria for Welded Steel Moment-Frame Buildings, 2000.
[3] 蔡岳勳, 實尺寸鋼結構梁柱彎矩接頭試驗與分析, 國立交通大學, 2010.
[4] 廖文義、羅俊雄、洪思閩、鄧崇任, 鋼結構建築耐震評估、補強及修復準則之研擬, 2003.
[5] 內政部營建署, 鋼結構設計技術規範-極限設計法, 2010a.
[6] AISC, Seismic Provisions for Structural Steel Buildings, American Institute of Steel Construction, 2010.
[7] H. Krawinkler, Earthquake design and performance of steel structures, 1996.
[8] Seismic Design of Steel Special Moment Frames: A Guide for Practicing Engineers, National Earthquake Hazards Reduction Program(NEHRP), 2009.
[9] Eric J. Kaufmann, Ming Xue, Le-Wu Lu and John W. Fisher, ACHIEVING DUCTILE BEHAVIOR OF MOMENT CONNECTIONS, 1996.
[10] FEMA, FEMA267-Interim Guidelines：Evaluation,Repair,Modification and Design of Steel Moment Frames, 1995.
[11] Helmut Krawinkler, Mahmud Zohrei, Cumulative damage in steel structures subjected to earthquake ground motions, 1983.
[12] 林克強, 梁翼切削與加蓋板補強之鋼梁與箱型柱抗彎接頭之設計與施工建議, 國家地震工程研究中心, NCREE-08-037,2008.
[13] 謝依平, 高層建築鋼結構韌性構架梁柱接頭之調查研究, 國立成功大學, 2012.
[14] 陳嘉有, 韌性鋼骨梁柱接頭行為研究, 國立台灣大學, 1995.
[15] 林昆德, 抗彎鋼骨梁柱接頭之行為, 國立台灣大學, 1996.
[16] Hae-Yong Park 、Sang-Hoon Oh, Design range of the damper of a T-stub damage-controlled system, 2019.
[17] Kazuhiko Kasai,Ian Hodgson,David Bieiman, Rigid-bolted repair method for damaged moment connections, 1998.
[18] 劉釋亞, 應用形狀記憶合金之自復位鋼構梁柱接頭開發, 國立成功大學, 2017.
[19] 林克強 莊勝智 林志翰 李昭賢 林德宏, 鋼構造梁柱抗彎接合設計手冊與參考圖, 國家地震工程研究中心, 2017.
[20] TZONG-SHUOH YANG,EGOR P. POPOV, BEHAVIOR OF PRE-NORTHRIDGE MOMENT RESISTING STEEL CONNECTIONS, 1995.
[21] AISC, Seismic Provisions for Structural Steel Building, American Institute of Steel Construction , 2005.