L形连接件滑移摩擦柱脚节点抗震性能研究

Study on seismic behavior of sliding friction column base with L-shaped connectors

柱脚节点是钢结构体系中的关键部位,其损伤将直接影响到结构体系的性能。基于损伤控制理念,提出了一种装配式L形连接件滑移摩擦柱脚节点。利用有限元软件ABAQUS建立了柱脚节点模型,考虑摩擦界面是否设置填充板和外连接件是否设置加劲肋,以及改变轴压比、连接件竖肢和水平肢厚度等因素,分析不同参数对节点受力模式、滞回曲线、耗能能力和损伤特征的影响。结果表明:柱脚节点主要承受摩擦力和轴压荷载的作用,柱端在受力过程中发生滑移,通过摩擦机制耗能,避免主体结构发生塑性损伤。填充板的设置增强了结构的摩擦性能,且在不同轴压荷载下均具有良好的延性和转动性能。在设置填充板的结构中,合理设置连接件竖肢厚度、水平肢厚度和加劲肋,在保证了节点摩擦耗能性能实现的同时,充分发挥了保护主体结构优势,达到了损伤控制的预期。

The column base is a crucial part of the steel structure system and its damage will directly affect the per⁃formance of the structural system.Based on the concept of damage control,an assembled L⁃shaped connector slip friction column base is proposed.The finite element software ABAQUS was used to establish a model of the column base.The effects of different parameters on the force pattern,hysteresis curve,energy dissipation capacity,and damage characteristics of the column base were analyzed by considering whether the friction interface is provided with infill plates,whether the outer connectors were provided with stiffening ribs,and changing the axial pressure ratio and vertical and horizontal limb thickness of the connectors.The results show that the column bases were mainly subjected to frictional and axial compression loads,with the column ends sliding during the stressing process.The main structure is prevented from plastic damage by the frictional mechanism of energy dissipation.The infill plates enhance the frictional properties of the structure,which provide ductility and rotation performance under different axial compression loads.In the structure with infill plates,the thickness of the vertical and horizontal limbs and the stiffening ribs are reasonably set to ensure that the frictional energy dissipation performance of the column bases is achieved while giving full play to the advantages of protecting the main structure and achieving the expectation of damage control.