全偏心钢结构梁-柱节点受力性能有限元分析

Finite element analysis of mechanical performance of steel eccentric beam-column joints

全偏心钢结构梁-柱节点由于偏心而引起应力集中,其受力性能较为复杂。首先对偏心连接梁-柱钢结构节点的受力特征进行分析,证明偏心节点核心区存在明显的三维扭转效应,导致偏心钢节点核心区的剪力相对于非偏心节点存在增大效应。通过有限元分析,研究了节点主要构造参数对核心区剪力增大系数的影响规律。分析表明:核心区板件厚度、梁柱腹板厚度对核心区剪力增大系数的影响较为显著,梁柱翼缘厚度对剪力增大系数具有一定影响,梁高、梁宽和柱高,对剪力增大系数具有一定的影响。通过数值算例,得到了剪力增大系数计算式并进行了验证。提出了适用于全偏心钢节点核心区的剪力计算式,可供工程设计参考。

The eccentricity of steel beam-column joints can cause stress concentration,having a bad influence on the mechanical property,and making it complex. This paper presented the study of the mechanical performance of the steel eccentric beam-column joints. The three dimension torsion effect was proved to exist in the eccentric steel joint,which made the shear force in the core area of eccentric joints larger than that of concentric joints. This paper conducted a series of parametric analysis,and the sensitive parameters affecting the shear force magnification obviously were obtained. The study shows that,the plate thickness of core area,the webs of beam and column have large influence on the shear force magnification,the flange thickness of beam and column has some influence. The height and width of beam,the height of column have same influence on the shear force magnification. After FEM analysis,a suggested calculation formula of shear force magnification is got and validated. Finally,a formula about the shear force of eccentric joints is proposed,which could be consulted.