高强钢芯筒-螺栓连接副装配式钢管柱节点抗震性能研究

Due to good torsional stiffness and stability, steel tubular columns are widely applied in steel frame structures. Because of closed column section, the high strength bolt cannot be used for connecting of steel beam and column directly. Steel beam can be connected to the tubular column by the transition members such as diaphragms or ring-stiffeners, but the disadvantages are large quantity welding work and the brittle fractures under the strong earthquakes. The blind bolts can be used for connection of tubular column and beam directly, but the main disadvantages of blind bolt connections are insufficient anchorage strength and complex construction. Now the steel tubular column frame joints fabricated by the high strength steel core tube-bolts assembly are proposed. Using high strength steel plates instead of the nuts, tapped steel plates can be combined with the bolt as a new kind of assembly. Firstly, insert the core tube into the tubular column and fix at steel beam position, then drill and tap on the core tube at the bolts position. The bolts go through the beam endplate and column wall plate, and screw into the tapped holes, the connecting is completed. The advantages of these new fabricated joints are clear load transferring path and simplify construction. In order to investigate the mechanical properties of this new kind of bolt assemblies and the seismic behavior of these new fabricated joints, the method combined experimental research and theory analysis will be used in this project. Researches on behavior of high strength steel plate-bolt assemblies under static loading, behavior of joints under static and pseudo static loading will be completed in this project. The influencing rules and influence factors will be discussed, the factors including stiffness, bearing capacity, damage mechanism, ductility and energy dissipating of these new joints. Design methods of high strength steel plates-bolts assemblies will be presented. Design methods and constructional measures of these new joints will be proposed also. The research has a great theoretical significance and practice value on the innovation of steel joints connection and the assembled steel structures.

钢管柱抗扭刚度大、稳定性好，在钢框架中应用较广。因截面封闭，与钢梁用常规螺栓连接时一般需辅以隔板、环肋等过渡件，焊接量大，强震下容易脆断。采用目前已有的单边螺栓可实现节点全螺栓连接，但存在锚固不足、操作复杂的问题。项目提出高强钢芯筒-螺栓连接副装配式钢管柱节点，用高强钢板替代螺母，攻丝后与螺栓配合使用：高强钢芯筒插入钢管柱对应钢梁处，在螺栓对应位置攻丝，现场将螺栓穿钢梁端板、柱壁板旋入芯筒丝孔即可，传力明确、构造简单。为深入研究这种连接副力学性能和梁柱节点抗震性能，项目采用试验研究和理论分析相结合的方法，拟完成高强钢板-螺栓连接副静力性能研究、梁柱节点静力和滞回性能研究，探讨影响节点刚度、承载力、破坏机理、延性和耗能的主要因素及影响规律。提出该新型连接副设计方法、节点抗震设计方法和构造措施。研究成果对钢结构节点连接创新和装配式钢结构发展具有重要理论意义和工程价值。

为解决钢管柱与钢梁焊接连接时需辅以隔板或环肋等过渡件且强震下容易脆断，已有的单边螺栓又存在锚固不足与操作复杂的问题，项目提出高强钢芯筒-螺栓连接副装配式钢管柱节点，用抗拉强度高、机械性能好的高强钢板攻丝后替代螺母，与常规高强螺栓配合使用，形成高强钢板组合螺栓。加工时先将高强钢芯筒插入钢管柱对应钢梁处并在螺栓对应位置攻丝，现场将螺栓穿钢梁端板、柱壁板旋入芯筒丝孔即可，传力明确、构造简单。项目深入研究了这种高强钢板组合螺栓连接副的力学性能和梁柱节点抗震性能，通过试验研究和理论分析相结合的方法，完成高强钢板-螺栓连接副静力性能试验研究与数值模拟，揭示高强钢板-螺栓受拉破坏机理，完成组合连接副抗拉、抗剪及连接节点性能的精细化数值模拟，获得节点受力机理和影响因素，推导并验证螺栓副抗拉承载力的计算公式，建议高强钢板组合单边螺栓最小端距取1.5d0，螺栓抗剪强度设计值取螺栓最小抗拉强度的0.39倍。完成高强钢芯筒-螺栓连接副装配式钢管柱节点静力性能和滞回性能研究，考察端板厚度、螺栓直径、芯筒类型等主要因素，获得组合节点承载力、刚度、延性和耗能能力的主要影响因素和变化规律，研究表明M20-20、M24-25两种钢板螺栓组合连接节点达到抗震规范的节点极限承载力连接系数要求，为半刚性节点；单调和循环两种加载方式的破坏模式相近，节点域应变和变形都较小，对节点转动角度影响可以忽略。组合节点均为梁端塑性铰破坏，节点延性好,满足“强节点、弱构件”的抗震要求。研究成果对装配式钢结构发展和灾后应急建造具有重要现实意义和工程价值。