摘要
为研究弦支穹顶结构支座处焊接空心球节点压弯状态下的力学性能,考虑焊接空心球壁厚、钢管外径、球外部和球内部加肋方式等因素的影响,采用正交法设计制作了4个试件.通过加载试验和有限元分析,获得了节点荷载-位移曲线、弯矩-转角曲线及破坏模式.进而考虑支座肋板构造的影响,分析了弦支穹顶支座焊接空心球节点压弯状态下的承载力及初始刚度.结果表明压弯受力状态下,焊接空心球节点球管连接处应力增长较快且最先达到屈服,节点在弯矩作用平面内压弯破坏;节点的压弯承载力及节点刚度与焊接空心球壁厚、钢管外径呈正相关;外部肋板构造对压弯状态下节点受力性能影响较小;在弯曲作用平面内合理设置焊接空心球内部加肋能有效提高节点的压弯承载力,但对节点刚度影响不大.
To investigate the mechanical properties of the welded hollow spherical joint as a support of the suspenddome structure,in consideration of the effect of hollow spherical wall thickness,steel tube diameter,and outer and inner rib forms, four specimens under compression-bending conditions were fabricated by using orthogonal method,to obtain load-displacement curves,moment-rotation curves,and failure modes,based on loading processes and finite-element analysis.The welded hollow spherical joint as a support of the suspend-dome structure was further examined for its bearing capacity and initial rigidity while considering the support rib form.The findings suggested that under compression-bending conditions,the intersection at the welded hollow spherical joint and the steel tube experienced faster-developing stresses and were first to yield.The joint failed by buckling on the bending momentum plane;the compression-bending capacity of the support joint and the joint stiffness were positively correlated with the hollow spherical thickness and steel tube diameter.The influence of the external rib on the mechanical properties of the structure under compression-bending was not significant.A reasonable setting of the internal ribs of the welded hollow spherical joint in the bending plane can effectively improve the compression-bending capacity,but has little effect on the initial bending stiffness.
引文
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