【作者】 谢川东； 王先铁； 林麟珲；

【Author】 Xie Chuandong;Wang Xiantie;Lin Linhui;School of Civil Engineering,Xi’an University of Architecture & Technology;

【机构】 西安建筑科技大学土木工程学院；

【摘要】 外张拉式自复位方钢管混凝土柱脚是一种便于预应力筋张拉和耗能部件更换的新型自复位柱脚节点。根据预应力筋与防屈曲钢板布置方式的不同,新型柱脚分为Ⅰ型、Ⅱ型和Ⅲ型。基于有限元验证方法,建立了足尺有限元模型,研究预应力筋及防屈曲耗能板的布置形式、预应力筋初始预应力和防屈曲耗能板面积对该类柱脚的性能影响。结果表明:在竖向荷载和水平往复荷载的共同作用下,外张拉式自复位方钢管混凝土柱脚的滞回曲线为典型的"双旗帜型",该柱脚具有良好的自复位能力和耗能能力;Ⅰ型、Ⅱ型和Ⅲ型柱脚经合理设计均可满足承载能力、自复位能力、耗能能力需求;增大初始预应力可提高柱脚的承载能力,对柱脚的耗能能力影响不大,但增大了预应力筋的最大应力,为避免预应力筋屈服,建议采取多预应力筋、低初始预应力方案。更多还原

【Abstract】 The self-centering(SC) concrete-filled square steel tubular(CFST) column base with external prestressing is a kind of column base connection that makes prestressing and replacement of buckling restrained steel plates(BRS plates) straightforward.Type I,Type II and Type Ⅲ of SC-CFST column base have been designed with different arrangement of PT strands and BRS plates and could be applied in a plane and three-dimensional self-centering frame.In this paper,based on the verified finite element approach,a series of full-scale finite element models were developed to investigate the effect of different type of SC-CFST column bases,the initial PT force,and the area of BRS plates.Findings show that the hysteretic curves of SC-CFST column base are a typical double-flag shape with great self-centering capacity and energy-dissipating capacity under gravity loads and horizontal loads.Besides,the demands of bearing capacity,energy-dissipating capacity,and self-centering capacity could be satisfied by designing the Type I,Type II and Type Ⅲ of SC-CFST column base reasonably.Moreover,increasing the initial PT force increases the bearing capacity and has little effect on the energy-dissipating capacity,but increasing the maximum stress of PT strands.Hence,a more PT strands,less initial PT stress design is suggested.更多还原