The cumulative plastic deformation demand for buckling restrained braces imposed by the strong motions in the 2023 Türkiye earthquake sequence  

作　　者：Fangzhan Gao Hanquan Liu Zhe Qu 

机构地区：[1]Institute of Engineering Mechanics,China Earthquake Administration,Harbin,150080,China [2]Key Laboratory of Earthquake Engineering and Engineering Vibration,Institute of Engineering Mechanics,China Earthquake Administration,Harbin,150080,China

出　　处：《Earthquake Research Advances》2024年第4期92-101,共10页地震研究进展(英文)

基　　金：supported by the Natural Science Foundation of China [grant number 52122811]。

摘　　要：The Türkiye earthquake sequence on February 6, 2023, was featured by the closely located earthquake doublet of M_(W)7.8 and M_(W)7.5. The consequent strong ground motions are supposed to be able to impose high demands on the ultra-low-cycle fatigue performance of metallic dampers in buildings, including the widely used buckling restrained braces. This study evaluates the cumulative plastic deformation(CPD) demands on bucklingrestrained braces(BRBs) in multi-story buildings imposed by the strong ground motions in the 2023 Türkiye earthquake doublet. Thirty-two records of the highest peak ground accelerations were selected from the strong motion database. Among them, eight captured the ground motions during both events, and the rest only captured the shaking of either of the events. The CPD demands on the BRBs in reinforced concrete frames with various fundamental periods, brace-to-frame stiffness ratios, and BRB ductility ratio are calculated by nonlinear time history analyses and are summarized in the form of enveloped spectra of CPD ratios at constant ductility. The results show that the CPD demands on BRBs increase with smaller brace-toframe stiffness ratios and larger BRB ductility ratios. The enveloped CPD demands are several hundreds of times the nominal yield deformation of the BRB, which are much higher than the CPD demands for the calibration tests of BRBs stipulated by AISC 341 in the US.

关 键 词：Türkiye earthquakes Long duration ground motion Cumulative plastic strain Constant ductility Low-cycle fatigue 

分 类 号：P315.9[天文地球—地震学] TU352.11[天文地球—固体地球物理学]