KT形RHS加强节点承载力试验研究与数值分析

Experimental study and numerical analysis of the bearing capacity of KT-shaped RHS joints

结合呼和浩特火车东站站房钢结构工程,针对其高频度使用的矩管KT形RHS节点,从受力、工艺和经济性出发,综合阐述了节点局部构造加强方式的工艺力学性能差异。采用模型试验和数值计算结合的方法,分析弦杆外套和弦杆内加劲两种强化方式的静力力学行为差异,数值分析采用引入Low-Speed Dynamics Damping Factor的非线性N-R方法,考虑材料屈服与破裂失效,基于Adina的隐式算法模拟模型的显式破坏特征。对节点进行抽象简化处理,综合考虑工艺力学性能,设计3组不同构造的KT形RHS节点,进行1∶2缩尺比例静力加载试验。分析两种强化方式对其质量控制、承载能力、破坏形态的影响,并与无任何加强措施的构件结构进行对比,结果表明,套管强化方式能够明显提高节点的承载能力和刚度,工艺性较好,可结合实际工程条件,提供节点强化设计参考。

KT-shaped rectangular hollow section（RHS） joints are widely used in the steel structure of the East Railway Passenger Station of Hohhot.The mechanical behavior of two local strengthening treatments is studied,from the aspects of bearing capacity,technics and economy.Model tests and numerical analysis are adopted to analyze the differences in statics behavior between the outer sleeve and inner stiffening strengthening measures.The nonlinear N-R algorithm is employed by introducing the Low-Speed Dynamics Damping Factor.In view of the yield and rupture failure of material,the explicit damage characteristics are simulated by using the implicit algorithm given by ADINA.The real joints are simplified in the experiment.One specimen without any strengthening treatment and two strengthened specimens are designed,considering the related mechanics.Static tests are conducted on the three specimens with a 1∶2 scale model.The influences of the two strengthening measures on quality control,bearing capacity and failure mode are analyzed,which indicate that the outer sleeve strengthening treatment with better technics can improve the bearing capacity and the stiffness of the joint significantly.