考虑局部构造影响的焊接节点抗震性能研究

Experimental study on seismic behavior of welded connection considering the effects of local structural form

针对普通梁柱节点在地震作用下易发生脆性断裂、钢结构梁柱节点的局部构造形式对结构抗震性能影响显著的问题,提出同时采用盖板加强与腹板削弱新型的等强节点构造形式.设计制作了6个缩尺比例为1/2的钢框架节点,研究了节点试件在不同构造形式与加载方式下的破坏形态、滞回曲线、骨架曲线、累积耗能等.试验结果表明：相比普通节点,考虑局部构造改进的节点能够避免梁根部的脆性破坏,实现塑性铰外移,塑性变形能力和耗能能力显著提高,同时分析了翼缘盖板长度与腹板孔径对节点抗震性能的影响.此外等强节点构造形式在几乎不改变节点承载力与刚度的同时,提高节点耗能能力,试验结果证明了等强节点构造形式的合理性.

Due to the brittle fracture of the ordinary beam-column connection,local structural constructions of steel beam-column connection had significant effects on seismic performance of structures. The equal strength structural constructions of connection were presented for cover strengthened and web weakened. Six beam-column connections of steel frame were designed at 1/2 scale in order to study the failure modes,the hysteresis curve,the curve skeleton and accumulative dissipated energy. The test results indicate that the connection considering local structural constructions could avoid brittle failure at the end of beam and make the plastic hinge outward from connection zone. Compared with the traditional connections,the plastic deformation capacity and energy capacity of the connections considering local structural constructions were significantly increased,and the influence of the seismic behavior of the connections with different flange cover plate length and the web aperture were analyzed. In addition,the equal strength structural constructions that did not change the bearing capacity and stiffness of the connection,could improve energy dissipation capacity of the connection,so it could be considered as a reasonable local structural constructions.