半刚接钢框架柱稳定承载力研究

RESEARCH ON THE STABILITY BEARING CAPACITY OF SEMI-RIGID STEEL FRAME COLUMNS

通过引入线刚度修正系数来考虑连接的非线性,采用变刚度螺旋弹簧单元模拟半刚性节点的特性,给出了考虑连接节点刚度影响的无侧移、有侧移钢框架柱的计算长度系数公式,讨论了半刚性连接对框架稳定承载力的影响。研究结果表明:节点刚度对纯框架柱计算长度系数有显著的影响。在无侧移情况下,有限元分析结果与理论计算值吻合较好;在有侧移情况下,节点连接的有效刚度与作用在框架梁上的荷载大小及形式等有关,准确确定有效刚度比较复杂,理论计算与有限元分析结果相差较大,理论解偏于保守。

In order to establish the formula of effective length factor for steel frame columns in sway frames and nonsway frames（ which considering the stiffness of joints）,the nonlinearity of the connection was discussed based on the revised factors of the line rigidity,and the characteristics of the semi-rigid joint were simulated by the variable-rigidity spiral spring element. The influence of semi-rigid connections on the stability bearing capacity of frames were discussed. It was shown that the joint stiffness had a notable effect on the effective length factors of the pure frame columns,theoretical calculation results and the finite element calculation results were coincident in braced frames cases,since the effective stiffness of the beam-to-column connections were related to the magnitude and type of loads acted on the beams,it was difficult to determine accurately the effective stiffness,which would lead to a large deviation between them,the theoretical solution was conservative.