钢框架梁腹板开孔型连接节点力学性能试验研究

EXPERIMENTAL RESEARCH ON MECHANICAL BEHAVIOR OF BEAM-COLUMN CONNECTIONS WITH OPENINGS ON BEAM WEBS IN STEEL FRAMES

钢框架梁柱节点的连接性能研究引起国内外的广泛关注,尤其是通过改善节点的变形性能从而提高结构的延性已成为钢结构研究的焦点。依据“强柱弱梁”的抗震设计原则,按照控制塑性铰位置的思路,对梁腹板上开孔的节点形式进行了反复荷载历程下的五个试件试验研究,探讨了梁柱节点区域内截面应力分布规律、滞回性能、节点破坏模式及极限承载能力,并利用ANSYS进行详细计算和对比分析。此外,通过一个单跨框架结构利用ABAQUS有限元程序计算分析,初步探讨了不同塑性铰位置对结构延性的影响。理论计算及试验结果表明,合理采用此类节点,可以使节点破坏模式从脆性破坏转变为梁的局部屈曲破坏,降低连接焊缝脆性破坏的可能性,达到了控制塑性铰位置的目的,从而改善框架结构的整体延性。

Steel frame structures have been widely used in multi-storey and high-rise buildings. Many studies about the connection had been carried out, especially with focus on its ductility. The connections play an important role in steel frame structures. Therefore, the study on the behavior of the beam-colunm connections to improve ductility as well as to prevent brittle failure was carried out in this research. In order to control the position of plastic hinge on the beam, a new type of connection with openings on the beam web was developed. Through the experimental investigation of five groups of specimens with different test variables under cyclic loads, the stress distribution of the section, the hysteretic behavior, the connection failure modes, and the ultimate capacity are presented in this paper. Moreover, the finite element method was also used to analyze the model and the results were compared with those of experiments. Theoretical calculation and tests results show that the failure modes of this kind of connections change from brittle damage to local buckling of beam web, which reduces the possibility of fragility damage of connections because of the improvement of the ductility performance of connections. In addition, the position of plastic hinge is under control with this connection form. The theoretical analysis and experimental results show that this type of connection is effective for beam column connection in multi-storey buildings and high-rise buildings.