研究节点的构造形式对于改善钢框架结构的延性、防止发生脆性破坏、提高结构的抗震能力有着重要的意义,为了系统全面地对比不同构造形式对于钢框架焊接节点抗震性能的影响以及构造形式对于节点在地震作用下的反应和破坏形态的改变作用,采用通用有限元软件ABAQUS建立非线性有限元模型,结合国内外已有的钢框架焊接节点拟静力试验,验证了建立的有限元模型对模拟局部屈曲的准确性和适用性。通过建立九种不同构造形式的节点模型,与标准节点在承载力、刚度、滞回性能、退化特性、断裂倾向指数、破坏形态以及塑性铰位置等进行对比分析,深入探讨不同构造形式节点的受力性能,为工程应用提供重要依据。分析结果表明:剪切域强弱对于节点的破坏模式有较大影响;同时考虑抗震效果、建筑要求以及经济指标,削弱型节点并没有过多的削弱节点承载能力以及刚度,并且滞回性能稳定,“狗骨头”型节点存在侧向稳定性问题,而腹板开洞型节点无论是在滞回性能还是破坏形态方面都具有较好的表现。
Structural constructions of connections play a great significant role on a steel frame structure to improve the ductility and aseismic capacity of the structure, as well as to prevent brittle failure. In order to have a systematic and comprehensive comparison among the aseismic behavior of different structural constructions of steel-frame-welded connections, an efficient and accuracy finite element model of ABAQUS is used. A non-linear finite element model is proved correct and applicable due to published steel frame connection quasi-static tests. Through establishing ten different structural construction connection models, the capacity, stiffness, hysteretic behaviour, degradation characteristics, fracture tendency index, failure modes and location of plastic hinges are compared and discussed in detail.The results show that: Shear region strength significantly affects the failure mode; considering the seismic-resistant effect, building requirements and economic indicators, the carrying capacity and stiffness of the weaken connections are not weakened too much and their hysteretic behaviours are stable; "Dog bone" type connection has a problem of lateral stability and the connection of holes in web either on the hysteretic behaviour or failure modes has a better performance.