基于防屈曲镍钛SMA棒的自复位隅撑钢框架:构件试验和结构行为  

SELF-CENTERING KNEE-BRACED STEEL FRAMES WITH BUCKLINGRESTRAINED NITI SMA BARS:COMPONENT TEST AND STRUCTURAL BEHAVIOR

作　　者：邱灿星 姜天缘 刘家旺 杜修力[1] QIU Can-xing;JIANG Tian-yuan;LIU Jia-wang;DU Xiu-li(Key Laboratory of Urban Security and Disaster Engineering,Ministry of Education,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学城市与工程安全减灾教育部重点实验室,北京100124

出　　处：《工程力学》2023年第10期33-46,共14页Engineering Mechanics

基　　金：国家自然科学基金项目(51808317,52178267)。

摘　　要：隅撑一般安装于框架梁柱的节点附近。和中心支撑相比,隅撑具有占用空间少、对建筑外观影响小、安装更为方便和震后更易更换等优点。超弹性镍钛形状记忆合金(SMA)在常温下能够具有“旗帜型”滞回曲线,兼具消能能力和自复位能力,近年来受到地震工程界的广泛关注。该文选取镍钛SMA棒为核心受力构件,利用防屈曲装置提出了基于防屈曲镍钛SMA棒的自复位隅撑(SCKB)。进一步的,以SCKB为关键抗震构件,提出了一种新型的抗震韧性钢结构,即自复位隅撑钢框架(SCKBF)。加工了缩尺比例的SCKB试件,并开展了往复加载试验。试验结果表明,SCKB受拉和受压时均拥有稳定的“旗帜型”滞回行为。为了评估SCKBF的抗震性能,根据底部剪力法设计了楼层数分别为3层和6层的结构,开展了罕遇地震下的弹塑性时程分析。计算结果表明:SCKBF能够满足规范对层间位移转角限值的要求;并且,结构的震后残余层间位移角几乎为零,体现了良好的震后功能可恢复性。该文为进一步的体系试验和抗震设计也起到了有益的铺垫。Knee braces are often installed at locations near the beam-to-column connections in frames.In comparison with concentrical braces,knee braces have advantages of using less space,generating less impact to architecture view and being installed more conveniently.Super-elastic shape memory alloys(SMA)exhibit flagshape hysteresis at room temperature,which indicates energy-dissipating capacity and self-centering(SC)capability.Accordingly,SMAs gained wide attention among the community of earthquake engineering.Combining NiTi SMA bar with buckling-restrained device,a novel knee brace,i.e.,SC knee brace(SCKB)was proposed.Further,a new seismically resilient steel structure was developed,which is named as SCKB frame(SCKBF).And the reduced scale specimen of SCKB was tested.The testing results show that,SCKB has stable flag-shape hysteresis under both tension and compression.To evaluate the seismic performance of SCKBF,two frames with 3 and 6 stories were designed by equivalent base shear method and subjected to a suite of earthquake ground motions.The nonlinear time history analysis indicates that SCKBF can well meet the drift target prescribed by the code.Besides,the structures have minimal residual inter-story drift ratios,implying good seismic resilience.It also sheds light on further experimental work and design method.

关 键 词：隅撑框架 自复位 形状记忆合金 构件试验 抗震性能 

分 类 号：TU391[建筑科学—结构工程]