翼缘削弱型外伸端板H形柱弱轴连接的力学性能分析

MECHANICAL PROPERTIES ANALYSIS FOR WEAK AXIS CONNECTIONS OF H-SECTION COLUMN WITH FLANGE WEAKENED EXTEND END-PLATE

为解决H形柱外伸端板弱轴连接抗震性能不足的问题,提出了一种翼缘削弱型外伸端板梁柱弱轴连接。利用有限元软件ABAQUS对削弱型端板节点和普通端板连接节点进行了低周反复荷载下的力学性能比较分析,并研究翼缘削弱几何参数对削弱型端板节点受力性能的影响。研究结果表明:削弱型端板节点的塑性转动能力平均值约为0.05 rad,与普通端板连接节点相比具有较好的抗震性能;削弱型端板节点破坏出现在远离节点域的削弱区域,而柱子基本完好,满足"强柱弱梁"的抗震设计理念,按照欧洲标准EC 3的连接刚度分类,削弱型端板节点属于半刚性连接;翼缘削弱几何参数中,削弱区距柱端板的距离、削弱长度以及削弱深度对削弱型端板节点的极限转角,塑性转动能力等方面均有显著影响,应合理选择削弱参数;根据美国标准FEMA-350中对削弱参数的规定,给出了翼缘削弱几何参数的建议取值范围。

In order to overcome the shortages of seismic behavior of extended end-plate connection on H-section column weak-axis,a new flange weakened connection for extended end-plate was put forward.The mechanical properties of the weakened end-plate connection and the common end-plate connection were analyzed by ABAQUS,and the effects of the flange weakened geometrical parameters on the mechanical properties of the connections were researched.The analysis results indicated that the average plastic rotatory ability of the weakened end-plate connections was about 0.05 rad,which was better than that of common end-plate connections on seismic performance.The all damages occurred in the weakened zone were far away from the panel zone,and the columns still maintained elastic state to meet the seismic design concept of ＂strong column and weak beam＂.In accordance with the connection stiffness classification in Euro Code EC 3,one of the European specification,weakened end-plate connections were semi-rigid connections.In geometric parameters of weakened flange,the distance between the weakened zone and the column butt plate,weakened length and weakened depth had significant influence on the limit rotation angle,plastic rotation ability of weakened end-plate connections and so on,and the weakened parameters should be selected reasonably.According to FEMA-350,the recommended range of flange weakened geometrical parameters were given.