【作者】 冯勇；

【导师】 崔佳；

【作者基本信息】 重庆大学 ， 结构工程， 2010， 硕士

【摘要】 伴随空间钢结构的广泛运用,由其发展而来的空间交错桁架结构体系日趋登上“建筑结构舞台”,成为一种新型结构体系。国内最近正在修建中的重庆国泰艺术中心便采用了此类结构,形成了独特的桁架“题凑”外形。构成空间交错桁架体系的单榀桁架在三维空间体系中彼此既不同在一个方向,也不在同一个水平面上,节点及杆件数量繁多,空间关系复杂。纵横相交各榀桁架连接节点构造特殊,节点形式复杂多变,具有空间性,且节点处荷载较大,是整个结构受力复杂而又关键的部位。有关空间交错桁架连接节点的理论和试验研究在国内外都还较少,没有相关资料可供参考,因此有必要通过试验来填补该领域研究的空白,以为今后空间交错桁架节点设计和研究提供试验依据。本文借助重庆国泰艺术中心的工程背景,结合其独特的桁架“题凑”结构设计,通过对空间交错桁架独有的三种特殊节点形式在拉力和剪力共同作用下进行足尺试验研究,后期采用大型有限元分析软件—ANSYS进行模拟加载计算,并对两者的数据结果作出分析对比。通过试验与有限元分析相结合的研究方法,本文对空间交错桁架节点做了如下部分研究工作:(1)通过3个特殊构造的空间交错桁架节点足尺试件的拉剪静力破坏试验,对试件整体位移、连接节点区域沿拉力和剪力方向的相对变形、节点区域应力进行了测试,并得出了节点的薄弱位置、破坏模式和极限承载能力。着重研究了节点区域的相对变形和应力分布。最终在试验数据综合处理分析的基础上得出结论,以供今后相关节点设计和研究参考。(2)通过对空间交错桁架节点试件的有限元模拟,对试件节点区域的相对变形、应力分布规律和极限承载力进行对比分析。试验结果表明:节点区域应力分布复杂,桁架主、支管间连接焊缝破裂导致结构失效,破坏呈脆性;试件达到极限承载力时位移较小,桁架杆件间连接焊缝先于连接节点破坏,此类连接节点在静力作用下能够满足空间交错桁架杆件的传力要求。更多还原

【Abstract】 Space staggered truss structure system, developed from Spatial Steel Structure which is applied to the industry extensively, plays a role in“architectural structure stage”as a new structural system. Chongqing GuoTai Arts Centver which is recently under construction adopted such structure, forming a unique“TiCou”shape truss。In three dimensions each truss unit that formed the space staggered truss is neither at the same direction nor in the same plane. Therefore, with a large number of nodes and members, the spatial relation is complicated. Due to complex node forms and large load bearing, the unique nodes jointing staggered truss is the important part that bears different force. There are few theories and experimental study about nodes of space staggered truss at home and abroad and even fewer relevant material for referencing, hence it is necessary to fill in the gap by experimental results in order to provide basis for further space truss designs and research.Along with Chongqing GuoTai Art Centre’s project, full-scale experimental studies of space staggered truss’three kinds of particular node have been performed under the combined action of tension and shear, basing upon Chongqing GuoTai Art Centre’s unique“TiCou”truss design. In the later stage, the large-scale finite element analysis software---ANSYS has been employed to simulate loading calculation and data collected have been analyzed and contrasted.In the thesis, the following studies on space staggered truss node have been carried out by means of experiment and finite element analysis:(1) The absolute horizontal displacementof the specimen, relative deformation of node region along the direction of tension and shear, stress of the node region have been obtained from the tension and shear static force destruction test of three distinctive full-scale space staggered truss nodes specimens. In addtion, the weak location of nodes, failure mode and ultimate bearing capacity have been tested. The relative deformation and stress distribution have become the focus. The conclusions draw upon the final data analysis could provide reference for future node designs and research.(2) Based on finite element simulation, comparison has been made with data collected from relative deformation of specimen’s node region, law of stress distribution and ultimate bearing capacity.The conclusion verifies that stress distribution around node region is complex; the rapture of weld seam connecting main tube and branch tube could cause structure failure and brittle fracture; small displacement of the specimen at its ultimate bearing capacity and the rapture of weld seam linking truss members before the break of nodes indicate that this kind of nodes could mthe force transfering of space staggered truss under static force.更多还原