双拱结构X型钢管相贯节点试验研究

Experimental investigation of X-joint in double-arch structure

结合曹娥江新型双拱空间钢管结构闸门工程,对3种X型相贯节点形式(无加强、肋板加强型和套管加强型)进行了静载和反复加载试验.通过分析静载试验数据发现,相对于无加强节点试件,肋板加强型节点试件极限荷载提高不是很显著,套管加强型节点试件极限荷载提高较大.两种加强措施对于节点的局部应力减小作用不大.从极限荷载和局部应力两方面比较可知,对于支管的轴向刚度大于主管的径向刚度的节点,主管管壁的加强(套管加强型)是一种较为合适的方法.通过分析反复加载试验数据也发现,3种形式节点的滞回曲线都比较丰满,节点的延性较好,反复加载和单向加载节点试件的破坏形式相近.

Three types of X-joint, named separately as joint without reinforcement, joint reinforced with ribbed plate and joint reinforced with sleeve, were proposed and researched in static and cyclic experiments based on the Caoe River double-arch gate project. Comparing to the joint without reinforcement, the ultimate load of the joint reinforced with sleeve shows a prominent increase while the joint reinforced with ribbed plate only owns an inconspicuous increase, and both the reinforcement joints cannot effectively decrease the local stress. Comparisons of the ultimate load and the local stress show that the reinforcement with sleeve is more suitable for the joint with more axial rigidity in branch-tube and less radial rigidity in main-tube. The cyclic curves of three joints are chubby and have good ductility, and the failure mode under the cyclic experiment is similar to that under the static experiment.