国家体育场桁架柱内柱多腹杆焊接节点性能研究

对国家体育场钢结构桁架柱的节点进行了比例为1∶5的缩尺模型试验研究和有限元分析。该节点为主桁架梁与桁架柱的连接节点,由1根菱形内柱与11根箱形截面腹杆形成的复杂空间管节点,并且节点内布置了许多加劲肋。论文介绍了节点的试验方法,描述了整个加载过程中节点行为和最后的破坏模式。从节点受力性质、构造、几何尺寸等角度,讨论了节点的破坏机理。研究表明节点的薄弱环节出现在受压腹杆,发生局部屈曲。弦杆内设置加劲肋是防止弦杆板件塑性破坏和局部屈曲的有效构造措施。论文提出了实际结构中该节点设计和制作时应采取的措施。

Behavior of welded joint of trussed columns with multiple web members in the National Stadium

Static test and finite element analysis of the welded joint of steel trussed columns in the National Stadium were carried out on scale model.The joint was the connection between a trussed beam and a trussed column,in which 11 box-section webs were welded to a rhombic chord to form a complex multiplanar tubular joint.Moreover,many stiffeners were arranged inside the joint.The experimental method,behavior within the whole loading period and final failure mode of the joint are described in this paper.Its failure mechanism is discussed through the investigation on the forces applied to the webs as well as joint geometries. It was concluded that the weak zone of the joint was located at the ends of compressive webs,where local buckling occurred.Arranging stiffeners inside the chord was effective to prevent the chord from yielding and local buckling.Measures for strengthening the joint is suggested for its design and fabrication of real structures.