基于梁-柱连接转动模型变截面门式刚架抗震承载力分析

Analysis on seismic bearing capacity of portal frame with tapered members based on beam-column connection rotational model

轻型门式刚架结构变形能力小、延性性能较低,地震对其影响不可忽略。传统计算中梁柱连接通常按刚性节点考虑,但端板连接节点具有明显的半刚性特征,考虑节点转动影响的抗震承载力计算对于结构设计有着重要意义。本文在变截面门式刚架梁-柱端板连接转动关系研究的基础上,将节点域转动模型导入整体结构中,以转动弹簧形式模拟梁柱连接。针对简化模型进行分析,与试验以及全尺寸实体单元有限元模型计算结果比较发现,其在承载力计算上精度较高,误差在10%以内,满足工程应用要求。本文研究将简化变截面门式刚架结构的抗震承载力计算,具有较好的理论与工程意义。

Through the pseudo-static test research of the whole portal frame with tapered members, which has small plastic deformation, poor energy dissipation capacity, low ductility performance, and the impact of earthquakes is difficult to be ignored. According to the standard for steel structure of light-weight building with gabled frames, the seismic design is clearly defined. The seismic load can be calculated by bottom shear force method, and seismic capacity calculation considering the joint turning influence is very important for the structural design. On the basis of the research on the rotation model of beam-column end-plate connection of single-story single-bay portal frame with tapered members, the rotating model of the joint region is introduced into the whole structure and the rotation spring is simulated as beam-column connection. Through the analysis of the simplified model and comparison with the results of test and the finite element model, the accuracy is higher and the error is less than 10%, which meets the engineering application requirements. In this paper, the seismic bearing capacity calculation of the portal frame with tapered members is simplified, and it has good theoretical and engineering significance.