局部可更换钢框架梁-柱节点受力性能研究

Study on Mechanical Behavior of Partially Replaceable Steel Frame Beam-column Joints

基于保险丝和塑性铰外移理念,将外伸端板连接、削弱型和拼接型连接的优点进行整合,提出一种局部可更换钢框架梁-柱连接节点。选取端板连接和拼接节点2个典型试验进行模拟,验证有限元建模过程的可靠性,然后对试件进行变参数分析,研究短梁翼缘削弱深度、削弱长度、短梁长度对节点承载力、耗能能力及延性的影响。结果表明:通过对H型短梁翼缘削弱,实现了塑性铰外移的目的,使地震作用下的塑性变形主要集中于短梁上,其他构件保持弹性,具有良好的震后恢复能力;参数对节点力学性能的影响程度由大到小依次为削弱深度、削弱长度、短梁长度,随着翼缘削弱深度的增大,节点的承载力有明显降低,而耗能能力和延性有所提高;同时随着翼缘削弱长度的增大,节点的最大承载力有所减小,而延性系数有所增大;短梁长度对节点力学性能的影响基本可忽略不计。

Based on the concept of fuse and plastic hinge outward movement,the extending end plates were connected integrating the advantages of weakened and spliced connections,a locally replaceable steel frame beam-column connection node was proposed.Two typical tests of end plate connection and splicing joint were selected for simulation to verify the reliability of the finite element modeling process,and then the specimen was analyzed with variable parameters to study the influence of the weakening depth,weakening length,and short beam length of the short beam flange on the bearing capacity,energy consumption capacity and ductility.The results show that by weakening the flanges of the H-shaped short beams,the plastic hinges are moved outwards,so that the plastic deformation under the earthquake is mainly concentrated on the short beams,and other components maintain elasticity and have good post-earthquake recovery capabilities.The degree of influence of parameters on the mechanical properties of the joint from large to small is weakening depth,weakening length,short beam length.As the flange weakening depth increases,the bearing capacity of the joint is significantly reduced,while the energy consumption and ductility are improved.At the same time,as the value of the weakened flange length increases,the maximum bearing capacity of the joint decreases,and the ductility coefficient increases.The influence of the short beam length on the mechanical properties of the joint is basically negligible.