全尺寸雙核心自復位斜撐及夾型挫屈束制斜撐耐震試驗

Seismic Tests of Full-Scale Dual-Core Self-Centering Braces (DC-SCBs) and Sandwiched Buckling-Restrained Braces(SBRBs)

周中哲(Chung-Che Chou) ； 鍾秉庭(Ping-Ting Chung) ； 鄭宇岑(Yu-Tsen Cheng)

《結構工程》 31卷1期 (2016/03) Pp. 61-83

https://doi.org/10.6849/SE.201603_31(1).0003

摘要

雙核心自復位斜撐(Dual-Core Self-Centering Brace，DC-SCB)是利用斜撐中的兩組拉力構件束制斜撐中的三組鋼受壓構件，及第一核心構件與外層構件之相對位移進行摩擦消能，使斜撐受軸拉與受軸壓下提供自復位及消能能力，即在大變形下具有回到零殘餘變形的能力；夾型挫屈束制斜撐(Sandwiched Buckling-Restrained Brace，SBRB)則是利用兩組獨立分離的圍束構件束制斜撐中的核心構件，使得斜撐受壓不會挫屈而產生飽滿的遲滯消能。本研究主要目的為測試及比較在層間側位移角2%下有相同最大軸力設計條件之雙核心自復位斜撐(DC-SCB)和夾型挫屈束制斜撐(SBRB)的勁度、能量消散、殘餘變形及耐用性能等耐震行為，因此設計及試驗兩組7409 mm長之斜撐(DC-SCB 1 與SBRB 1)及兩組7560 mm長之斜撐(DC-SCB 2與SBRB2)，其中DC-SCB 1與DC-SCB 2之拉力構件均使用D16(直徑15.24 mm)高強度鋼絞線(ASTMA416 Grade 270 Steel)，此四組斜撐分別進行六次反覆載重試驗。試驗結果顯示，雙核心自復位斜撐有穩定的自復位與能量消散之能力，夾型挫屈束制斜撐有飽滿的遲滯消能，四組斜撐之耐震性能均符合AISC (2010)規範針對斜撐要求在最小層間側位移角2%前不破壞原則，更可達層間側位移角2.5%而不破壞，雙核心自復位斜撐與夾型挫屈束制斜撐之最大軸力分別可達5800 kN 與6400 kN，兩種斜撐之最大軸力拉壓差均在1.07以下，夾型挫屈束制斜撐在六次階段試驗的累積非彈性軸向變形比(累積韌性容量)為878~1422，均超過AISC (2010)對於挫屈束制斜撐要求之200，並也實際應用於臺灣及中國新建的建築物作為抗震消能的主要構件。

關鍵字

雙核心自復位斜撐 ； 夾型挫屈束制斜撐 ； 耐震試驗

並列摘要

This paper presentsseismic tests of full-scale dual-core self-centering braces (DC-SCBs) and sandwiched buckling-restrained braces (SBRBs). The DC-SCB has a flag-shaped hysteretic response with high axial stiffness and minimal residual deformation, exhibiting a self-centering mechanism. The SBRB like conventional BRBs has much higher energy dissipation capacity than the DC-SCB, but larger residual deformations are expected for structures equipped with SBRBs. The primary objective of the study was to conduct seismic tests that established a direct comparison basis between two DC-SCBs and two SBRBs designed with similar axial capacity and length. A total of DC-SCBs and SBRBs that were about 7.5 mlong and had maximum axial forces from 1500 to 6000 kN were tested to evaluate their cyclic behavior and durability. In general, these tests showed that the DC-SCB and SBRBexhibit robust cyclic performanceswith good deformation capacity and durability. The axial elastic and post-elastic stiffnesses of DC-SCB were around two and five times those of SBRB, indicating that DC-SCB is more effective to resist lateral forces than SBRB in structures. Some new buildings in Taiwan and China have adopted SBRBs as main earthquake-resisting members.

並列關鍵字

Dual-core self-centering brace (DC-SCB) ； Sandwiched buckling-restrained brace (SBRB) ； Seismic tests