扩翼式弱轴连接节点的滞回性能分析

Hysteretic performance analysis of weak-axis widened beam flanges connections

为了实现传统弱轴连接中的梁上塑性铰外移,提出了弱轴扩翼式平齐加劲板连接(WWBF)节点,并运用有限元软件ABAQUS 6.14-1对扩翼式连接节点试验进行模拟验证后,对WWBF节点进行系列参数分析,得到合适的参数取值范围,并进一步验证了建议参数取值的适用性。结果表明,WWBF节点的荷载-位移滞回曲线均呈饱满的梭形,节点的耗能性能良好;扩翼三角板细部参数的变化对节点的初始刚度基本没有影响;随着扩翼三角板直角边长的增大,节点的峰值承载力逐渐小幅增加,梁截面的屈曲在扩翼末端的梁截面上发展,梁上塑性铰逐渐远离梁柱连接处;当扩翼三角板直角边长比保持不变时,随着短直角边长a的增大,焊缝两端的断裂指标有所减小,焊缝发生脆性断裂的可能性降低;当扩翼三角板短直角边长a保持不变时,随着直角边长比的减小,焊缝处的最大应力三轴度指标及断裂指标有所增大;建议梁端扩翼三角板的直角边长比取为1∶2~1∶3。

In order to move the plastic hinge away from the beam flange welds in the traditional weak-axis connection,this paper proposes weak-axis widened beam flanges flat stiffening plate(WWBF)connections.The finite element software ABAQUS 6.14-1 is adopted to conduct the series parameter analysis for the WWBF connections after validating the modeling methods by comparing to the test specimen to obtain the appropriate parameter value range,whose applicability is validated then.The results showed that the loaddisplacement hysteretic curves of WWBF are plump and indicate the good dissipation capacity.Different values of the widened beam flanges have relatively small influence on the initial stiffness of the connection.As the right leg length of the widened beam flanges triangulation increases,the maximum bearing capacity increases slowly,the beam buckling occurres in the beam section at the end of the widened beam flanges,and the plastic hinge gradually moves away from the beam-column connection.When the ratio of the right leg of the widened beam flanges remains unchanged,the larger the small right leg a,the smaller the rupture index at the weld ends.When the small right leg a remains unchanged,the smaller the ratio of the right leg,the larger the maximum triaxiality index and rupture index at the weld ends.It is suggested that the ratio of the right leg of the widened beam flanges could be set to 1∶2~1∶3.