鋼梁與鋼管混凝土柱穿透式螺栓接頭及預力消能接頭之耐震行為研究

Seismic Behavior of Bolted Connections and Energy-Dissipated Connections for Concrete-Filled Steel Columns and H-Beams

蔡昇甫(Sheng-Fu Tsai)

指導教授 ： 吳賴雲

共同指導教授 ： 鍾立來

國立臺灣大學/工學院/土木工程學研究所/博士(2006年)

https://doi.org/10.6342/NTU.2006.00861

摘要

鋼梁與鋼管混凝土柱之結構系統，具有高強度、高韌性、施工快速等特性。然而，由於其梁柱接頭的行為複雜，故此結構仍未廣泛應用於實務上。針對此結構系統之梁柱接頭，本研究先後研發穿透式螺栓梁柱接頭及預力消能梁柱接頭之設計方法，並分別建立其力學模型，最後再以一系列全尺寸結構試驗加以驗證其耐震性能。
本文將研究成果依序分成二篇論文發表。第一篇論文主題為「鋼梁與鋼管混凝土柱穿透式螺栓梁柱接頭之耐震行為研究」，主要內容如下：鑑於傳統梁柱接頭係在工地以背墊板從事全滲透銲方式接合，但此種接合方式，背墊板與柱翼板間難免存有縫隙，當梁端受力時，縫隙引致應力集中，裂縫甚至深入柱板，並將銲道整個剝離，使得梁、柱及梁柱交會區在尚未充分發揮其強度與韌性前，梁柱接頭即告破壞。針對上述缺點，本篇論文提出一套以螺栓接合梁與柱之接頭設計方式，並以力學理論模型及一系列結構耐震試驗加以驗證，結果證明此種梁柱接頭具備高勁度、高強度、高韌性及消能性良好等優點。
第二篇論文主題為「預力鋼梁與鋼管混凝土柱接頭輔以X字型消能鋼板之耐震性能驗證」，主要內容如下：第一篇論文所提出之穿透式螺栓梁柱接頭，可於受震時產生飽滿的遲滯迴圈，具備高勁度、高強度、高韌性及消能性良好等優越耐震性能，大幅改善傳統梁柱接頭發生脆性破壞之缺點，確保結構受震時之安全性。然而卻尚無法改善當地震發生過後抗彎構架會產生殘餘位移的缺點。於是，本研究進一步思索兼顧受震安全性及震後復原性之梁柱接頭設計方法，引進預力與消能器的觀念，提出一套以X字型鋼板為消能器的預力結構梁柱接頭設計方法，期使結構系統受地震力作用時，能具有自行復位能力，且充分發揮X字型鋼板之消能功效，確保主結構元件不受破壞。經由力學理論模型及一系列結構耐震試驗加以驗證結果，證明此梁柱接頭不僅能以X字型鋼板吸收絕大部分傳遞至結構物之地震能量，且無論在勁度、強度、韌性、消能及自行復位能力等方面，均具有優良之耐震性能。
針對上述二類梁柱接頭設計方式，本研究分別建立的梁柱接頭力學模型，其所推導出來的理論公式均與試驗結果相當接近，故本文所提出之梁柱接頭設計方法、力學模型推導公式及試驗結果，可供各界參考。

關鍵字

鋼管混凝土 ； 螺栓式梁柱接頭 ； 預力結構 ； 消能接頭 ； X字型消能器

並列摘要

The structural system of steel beams and Concrete-Filled Tubular (CFT) columns has the characteristics of high strength, ductility, load bearing capacity and fast construction. However, the behavior of beam-to-column connections is so complicated that it is not widely applied in practice. For the beam-to-column connection of this structural system, this study developed two detailed design methods, which are bolted connection and pre-stressed energy-dissipated connection. This study first established a series of mechanics theoretical models for these beam-to-column connections. Then a series of structural seismic-resistant tests was performed to verify the seismic resistance of these connections.
The first topic of the study is “Seismic Behavior of Bolted Connections for CFT Columns and H-Beams”. Traditional beam-to-column connection was fully penetrating welded by backing bars on jobsites. This connection method usually produces voids between backing bar and column flange. When beam end is loaded, the voids will result in stress concentration, grow into column plate and tear the welding zone apart. Because of the weakness of welding zone, the beam-to-column connection failed before the strength and ductility of beam, column and panel zone were fully developed. In this paper, a new design of bolted beam-to-column connections for CFT is proposed. A mechanical model is established and a series of cyclic loading experiments have been conducted to verify it. The experimental results and theoretical results are very close, which demonstrates that the bolted connections have superior seismic resistance in stiffness, strength, ductility and energy dissipation mechanism.
The second topic of the study is “Earthquake-resistant Behavior for Connections of Pre-stressed Steel Beams and CFT Columns with X-shaped Dampers”. The bolted beam-to-column connection design mentioned above have full hysteretic loops and advantages as high stiffness, strength, and good energy dissipation ability, but the moment-resistant structure will have residual displacement after an earthquake. Therefore, Pre-stressed structural system and energy-dissipated element concept were applied in the study.
This study proposed a detail design which used X-shaped dampers as energy dissipation elements for pre-stressed steel beam and CFT column connection. The structural system is expected to retain self-centering ability after an earthquake since the X-shaped dampers are energy dissipation elements that can protect the major structural elements from damage.
This study established mechanics models for this beam-to-column connection. A series of tests was performed to prove the seismic behavior of the connection. The experimental results showed that the beam-to-column connection not only can absorb most seismic energy through the X-shaped dampers, but also can be repaired fast and easily after earthquake. Besides, this study verified that the proposed beam-to-column connection has superior stiffness, strength, ductility, energy dissipation and self-centering ability.
For the two design methods, the theoretical equations derived from beam-to-column connection mechanics model established in this study was proven realistic by experiments, so the equations and experimental results proposed in this study are worth referencing.

並列關鍵字

concrete filled tube (CFT) ； bolted beam-to-column connection ； pre-stressed structure ； energy-dissipated connection ； X-shaped damper

參考文獻

PART I Seismic Behavior of Bolted Connections for CFT Columns and H-Beams

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