一种新型单层网壳节点的力学性能研究

针对空间网壳结构提出了一种适用于矩形杆件的新型焊接端板节点. 为研究该节点的力学性能，制作了一个1∶2的缩尺模型进行静载试验研究，试验得到了节点荷载-应变曲线、荷载-位移曲线及破坏模式，结果表明节点应力水平较低，构造合理；在对有限元分析结果进行验证之后，分析了节点变形、破坏形态、应力应变分布及传力机理随节点端板厚度t₂与杆件壁厚t₁之比、水平夹角α、平面外角度β的变化规律，分析结果表明，该节点形式有较高的承载能力，其中水平夹角α对节点极限承载力影响较大，且在60° 前后影响作用不同；最后，基于有限元分析结果提出了该类型节点的极限承载力计算公式，可供设计参考. 

Research on Mechanical Behaviours of New Joints of Single-Layer Reticulated Shells

A new kind of welded end-plate joint for a reticulated shell with a rectangular cross-section rod was proposed. To investigate the mechanical behaviour of the proposed joint, a test model at a scale of 1∶2 was designed and subjected to static loading tests. Load-strain curves, load-displacement curves, and failure modes were obtained, showing the joint’s performance to be low stresses at a reasonable level of detail. After validating the results of numerical models, the effect of the ratio of end-plate thickness (t₁) to tube thickness (t₂), the angle between the tubes α and the out-of-plane angle β on distortion of the joint, failure mode, and strain distribution were analysed. The results showed that the joint possessed a good load-bearing capacity; the angle α has a significant impact on this index, with 60° being a critical point. On the basis of the finite element analysis results, a formula that could provide a reference for design work was introduced for calculating the bearing capacity of the joint.