国家体育场焊接方管桁架单K节点试验研究

为考察构造复杂的国家体育场焊接方管桁架单K节点的受力性能和承载力,进行了两个典型节点的1∶3缩尺比例的模型试验和有限元分析。试验结果表明,节点强于杆件,节点的极限承载力都能达到设计荷载水平的2倍以上,且节点区范围内的板件未观察到局部失稳或断裂现象。有限元分析能较好地模拟试验现象。试验结果和有限元分析结果证明,节点区的板件局部加厚和内置加劲肋等加强措施是有效的。

Experimental research on single K-joint in roof truss with welded box section members used in the National Stadium

The behavior and ultimate capacity of single K-joint in the roof truss with welded box section members used in the National Stadium were experimentally researched.Two specimens at one-third scale of their prototypes were tested under monotonic loadings,along with FEM analysis.The test results indicated that the joint was stronger than the connected members,and the ultimate capacity of the joints was about twice as large as the design load.Neither local buckling nor fracture of the plates in the joint was observed in the tests.The results of FEM analysis match the test well.It is proved that the reinforcement of the joint such as increase of the plate thickness in the joint zone and arrangement of internal stiffeners in the joint are quite effective.