【摘要】 铝合金网壳结构在大跨空间结构中具有广泛的应用前景.南京牛首山佛顶宫大穹顶工程中采用了铝合金网壳结构,其节点包含两种截面杆件,均使用不锈钢环槽铆钉与节点盘进行紧固连接,形成了特殊形式的箱形-工字形盘式节点.为研究铝合金箱形-工字形盘式节点在面外弯矩作用下的传力机理、变形性能、节点刚度、破坏模式和极限承载力,开展了箱形-工字形盘式节点整体试件的静力加载试验,使用有限元软件ABAQUS对试验加载全过程进行了数值模拟,并将试验结果与相同截面铝合金箱形-工字形盘式节点相连对肢节点的试验结果进行对比分析.试验结果表明:南京牛首山佛顶宫大穹顶工程中采用的铝合金箱形-工字形盘式节点为半刚性节点,节点刚度较大,整体延性相对较小;在较大面外弯矩作用下构件的上节点盘发生屈曲变形,试件加载破坏时下节点盘仍处于弹性阶段,杆件连接部位腹板出现明显屈曲变形,杆件与上节点盘连接处发生断裂破坏.足尺有限元模型的数值模拟结果与试验结果吻合较好,具有工程应用可靠性.与相同截面的铝合金箱形-工字形盘式节点相连对肢节点试验结果相比,铝合金箱形-工字形盘式节点6根连接杆件之间的相互作用提高了节点刚度,但在一定程度上降低了节点的延性和抗弯承载力,在设计和使用过程中需进一步加强和改进.更多还原

【Abstract】 Aluminum alloy reticulated shells have shown prospects for wide application in large-span space structures.In the Nanjing Oxhead Mountain Buddha Palace project,China,aluminum alloy box-I section member TEMCOR joints are used in its reticulated shells.The joint plates are connected by stainless steel swage-locking pins with joint members of two sections.In order to study the mechanical behavior,deformation performance,overall stiffness,failure mode,and moment resistance of these joints under out-of-plane bending load,a test of a full-scale specimen was conducted.The complete loading process was simulated by the general finite element software ABAQUS,and the test results were compared with their counterparts for the two opposing members.Test results showed that the aluminum alloy box-I section member TEMCOR joint is semi-rigid with high stiffness and poor ductility.Buckling deformations occurred in the upper plate under the out-of-plane bending load,and the lower plate was still in an elastic stage when the joint failed.Clear buckling deformations and fractures occurred in the webs of the connecting parts of the members and the upper plate.The numerical simulation of the full-scale finite element model agreed well with the experimental results,indicating its reliability in engineering applications.Compared with the joint of two opposing members,the stiffness of the joint was improved by the interaction between its members,although ductility and bearing capacity of the joint were reduced,requiring improvement for further engineering applications.更多还原