高层钢框架新型梁柱节点抗震性能试验研究

Experimental Research on Cyclic Behavior of New Types of Beam column Connections in Highrise Steel Frames

本文提出了三种焊接孔扩大型梁柱节点,完成了8个足尺试件在四种反复荷载历程下的破坏试验。对节点破坏模式和滞回曲线的比较分析表明,焊接质量是防止节点脆性破坏的首要保证,明显的焊接缺陷容易导致裂缝过早开始扩展,从而降低节点延性和耗能能力。节点局部构造尤其是焊接孔形状尺寸对于节点应力集中情况和节点破坏模式有很大影响。本文提出的焊接孔扩大型节点可以不同程度地缓解局部应力集中,同时通过采用较长的焊接孔,使节点破坏模式转变为梁翼缘的局部屈曲,降低了对接焊缝发生脆性破坏的可能,对节点延性有较大的改善作用。焊接孔扩大型节点构造也便于加工制作,是一种值得推荐的新型节点形式。

This paper reports the experimental results of several new types of beam column connections. Three types of Enlarged Weld Access Hole (EWAH) connection details are proposed and eight full size specimens are tested under cyclic loading. Experimental results show that welding quality is the most important issue in achieving connection ductility. Weld access hole geometry and size have significant effect on ductility and failure mode of the connection. EWAH connections can relax the stress concentration at the end of access hole and introduce better ductility. With long access holes, the cause of EWAH connections fail will be turned to local buckling of the beam flange. This kind of failure mode reduces the fracture potential of the connection and improves connection ductility significantly.