摘要
普通支撑在荷载作用下易发生受压屈曲造成支撑刚度和承载力急剧下降,结构延性差。防屈曲支撑通过在支撑外围设置屈曲约束构件,有效约束支撑受压屈曲,保证支撑在整体失稳破坏前核心受力构件达到全截面屈服,使支撑在使用中屈曲耗能而不屈服,因此可用防屈曲支撑代替普通支撑。防屈曲支撑耗能的关键是核心受力构件与外围约束构件之间的间隙。间隙太小,可能导致核心受力构件过早局部屈服;间距太大,则外围约束构件发挥不了套箍作用,因此间隙的取值是防屈曲支撑设计的关键。本文提出一种混凝土约束型防屈曲支撑,并通过有限元计算分析核心受力构件与外围约束构件之间的间隙对其受力性能的影响。结果表明:本文设计的混凝土约束型防屈曲支撑能较好地发挥核心受力构件的承载能力,外围约束构件与核心受力构件间隙为1~3mm时,有良好的耗能能力。
The stiffness and bearing capacity of ordinary braces are easily reduced by buckling under load,which leads to poor ductility of structure.Buckling-restrained braces can effectively restrain the buckling of the braces under compression by setting restrained members on the periphery of the braces,which can ensure that the core bearing members of the braces reach full section yield before the overall unstability of the braces,so that the braces do not yield but dissipate energy through buckling during working.Therefore,BRB can be used to replace ordinary braces.The key to energy dissipation of BRB is the gap between the core load-bearing member and the peripheral restrained member.If the gap is too small,which may lead to premature partial yield of the core loading member.If the spacing is too large,the Peripheral restrained member can not play the role of hoop,so the value of clearance is the key to the design of BRB.In this paper,a kind of concrete constrained BRB is proposed,and the influence of the gap between the core member and the periphery restrained member on its mechanical performance is analyzed by finite element calculation.The results show that BRB ofthe concrete constrained designed in this paper can give full play to the bearing capacity of the core load-bearing members,andit has a good energy dissipation capacitywhen the gap sizebetween the peripheral restrained members and the core load-bearing members is 1~3 mm.
作者
谢永兰
吴翔强
杨少林
霍亮
阮浩
田振
姚雪佳
张东华
XIE Yonglan;WU Xiangqiang;YANG Shaolin;HUO Liang;RUAN Hao;TIAN Zhen;YAO Xuejia;ZHANG Donghua(China Construction Industrial Engineering and Technology Research Academy,Beijing,101300,China;Hangzhou Zhongchen Town Construction Co.,Ltd.,Hangzhou,310021,China)
出处
《建筑结构》
CSCD
北大核心
2021年第S01期940-943,共4页
Building Structure
关键词
防屈曲支撑
间隙
核心受力构件
外围约束构件
buckling-restrained brace(BRB)
gap
core bearing member
peripheral restrained member