低周往复荷载作用下可变梁高装配式钢框架节点力学性能研究

Research on mechanical performance of bolted height adjustable steel beam-to-column connections under low cycle reversed loading

在传统螺栓连接节点的基础上,提出一种可根据梁高在一定范围内调节节点连接高度的可变梁高装配式钢框架节点,适用于节点所连钢梁高度出现小范围变化时的情况。结合4个足尺试件在低周往复荷载作用下的试验研究及有限元分析,对采用不同L形连接件加强构造以及梁-柱连接对中方案时,节点的失效模式、滞回性能以及L形连接件的滑移情况进行了分析。结果表明,L形连接件的刚度将改变节点的受力性能,其椭圆螺栓孔构造会使节点在受力时产生一定的滑移,但该滑移对节点滞回性能的影响不明显;可忽略梁-柱连接对中方案对节点受力性能的影响;通过提高L形连接件的刚度,可使节点具有良好的滞回性能以及设计所期望的破坏模式;文中所采用的有限元分析方法可有效模拟节点滞回性能。该类节点可方便地应用于轻型装配式钢框架结构。

A kind of bolted height adjustable steel beam-to-column connection was developed based on traditional connections,which is applicable when the beam height changes only in a small range. The influence of L-shaped connector stiffening methods and beam-to-column connection centering schemes on the failure modes,hysteretic properties and L-shaped connector slippages of the connections were studied on the basis of the experimental and numerical results of four full-scale assemblies under low cycle reversed loading. The results show that: the stiffness of L-shaped connectors can change the mechanical behavior of the connections,and the presence of ellipse-shaped bolt holes on L-shaped connectors leaded to the slippage of the connections,which had negligible effect on hysteretic behaviors; the design desirable failure mode and better hysteretic properties of the connections can be achieved by improving the stiffness of L-shaped connectors; no significant effect of the beam-to-column connection centering patterns was detected; the modeling method illustrated in this paper can simulate the cyclic behavior of the connections properly. This kind of newly developed connections can be applied to the fabricated light-weight moment frames.