六杆四面体单元端板式节点受力性能研究  

Study on mechanical behavior of end-plate joint of six-bar tetrahedral units

作　　者：陈伟刚 董石麟[2] 周观根[1] 丁超 诸德熙[2] CHEN Weigang;DONG Shilin;ZHOU Guangen;DING Chao;ZHU Dexi(Zhejiang Southeast Space Frame Co.,Ltd,Hangzhou 311200,China;Space Structures Research Center,Zhejiang University,Hangzhou 310058 ,China)

机构地区：[1]浙江东南网架股份有限公司,浙江杭州311200 [2]浙江大学空间结构研究中心,浙江杭州310058

出　　处：《建筑结构学报》2019年第8期145-154,共10页Journal of Building Structures

基　　金：国家自然科学基金项目(51478420,51578491);浙江省博士后科研项目择优资助项目(2016-28)

摘　　要：提出了一种可满足六杆四面体单元装配化施工要求的节点形式——端板式节点.即六杆四面体单元的弦杆与腹杆相贯焊接于端板,通过端板上的高强螺栓实现单元之间的连接.设计并制作了2个足尺节点模型,分别考察其在压弯和轴拉荷载作用下的受力性能,得到了端板节点的位移、应变发展特点及破坏形态.采用ABAQUS软件进行考虑接触非线性的有限元分析,得到了杆件、端板及高强螺栓的应力和变形.试验和有限元分析结果表明:在压弯荷载作用下,端板节点发生杆件屈曲和近节点域处鼓曲变形破坏,且杆件屈曲破坏先于节点域鼓曲破坏;节点域高应力区主要集中在三杆相贯焊接形成“谷底”处;高强螺栓在整个加载过程中最大应力约为其屈服应力的10%.轴拉荷载作用下,节点发生端板拉屈破坏;位于缺口两侧的高强螺栓发生拉弯变形,建议适当增设加劲肋和增加端板厚度,以提高端板刚度.通过数值计算得到的端板节点宏观变形、荷载-位移曲线及部分荷载-应变曲线均能与试验结果较好吻合,反映了数值分析模型的有效性与准确性.An end-plate joint which could meet the needs of prefabricated construction for six-bar tetrahedral units is presented.Namely,the chord of the six-bar tetrahedral unit and the web are welded to the end plate,while highstrength bolts are used to connect the end plates between units..Two full-scale specimens were designed and fabricated to investigate the mechanical behavior of end-plate joint under axial tension and combined compression and bending.The development characteristics of the displacement and strain of the end-plate joint as well as the corresponding damage modes were achieved.Finite element analysis(FEA)with modeling nonlinear contact interaction was carried out by using ABAQUS.The stress and deformation of bars,end-plates and high-strength bolts were presented.It is observed from test and FEA results that the buckling of bars followd with the local buckling near joint region under combiend compression and bending.The high-stress zone locates at the"valley bottom"formed by weld intersecting of three bars.The maximum stress in high-strength bolts is about 10%of its yield strength during the whole loading process.Under the axial tensile load,the buckling of end-plates and the bending deformation of highstrength bolts are observed.Stiffeners and end-plates with higher thickness are suggested to improve the stiffness of the end-plate.The overall deformation,load-displacement curves and partial load-strain curves of the end-plate joints obtained by numerical calculation are agree well with the test results,indicating the validity and accuracy of the established numerical model.

关 键 词：六杆四面体单元 端板节点 静力试验 数值分析 受力性能 

分 类 号：TU393.3[建筑科学—结构工程] TU311.41