输电铁塔主材节点滞回性能研究

Research on the Hysteretic Performance of Leg Joint of Transmission Tower

为提高输电铁塔的强度与刚度,增强抗风能力,提升安全和使用寿命,输电铁塔主材双肢搭接节点是关键。对此,分别建立单一剪切面连接与双剪切面连接的螺栓连接节点有限元仿真模型。通过施加低周循环载荷获得了节点的滞回曲线,分析骨架曲线、吸能能力和刚度退化,研究输电铁塔螺栓连接节点在低周循环载荷作用下的吸能能力与力学性能。结果表明:单剪连接与双剪连接的节点线弹性变形过程基本一致,此后两种节点都出现滑移现象,双剪连接节点经历两次滑移过程,在螺栓滑移过程中,节点吸能能力更强。双剪连接节点极限承载能力更强,刚度保持更佳,吸能能力更强。

To improve the strength and stiffness of power transmission tower,enhance the wind resistance ability,improve the safety and service life,the tower leg joints are the key components.Therefore,finite element simulation models of bolted joints connecting single-shear plane and double-shear plane were established,respectively.The hysteretic curves of the two joints were obtained by applying low-cycle load.The skeleton curve,energy absorption capacity,and stiffness degradation were analyzed.The energy absorption capacity and mechanical properties of the bolted joint of transmission tower under low-cycle load were studied.Results show that:the linear elastic deformation processes of single-shear and double-shear connections were largely the same,both joints showed the phenomenon of sliding,and the double-shear connection experienced two slip processes.Above all,the double-shear connection during the process of bolt sliding,the energy absorption capacity of the joint was stronger,the ultimate bearing capacity,stiffness,and energy absorption capacity were better than those of the single-shear connections.