In order to reveal the mechanical properties of fabricated beam-column connection with inner sleeve composite bolts,experimental studies on three cross-shaped specimens with size proportion of 1/2 under low cycle reciprocating load was done,and the joint failure pattern,hysteresis property,stiffness degradation,the shearing angle curve of joint core and moment-rotation curves of connection were analyzed.The results show the failure pattern of the joint can be summarized into snap of high-strength bolt,buckling of extended end-plate and column wall,and fracture of welds of column under low cycle reciprocating load.The plastic deformation caused by slip of through high-strength bolt in the upper column concentrates on column wall and extended end-plate area and plastic hinge was formed,and the joint has well energy dissipation ability.Influenced by the through high-strength bolt which passed though the column wall,"symmetric concave bend" of the upper column wall arised under reciprocating load.With the increase of the inner sleeve thickness,shear deformation of joint core is reduced,and the shear stiffness increases.The joint has a certain rotational stiffness and shows the nature of the semi-rigid joints.The properties of proposed fabricated beam-column connection with inner sleeve composite bolts can be used into totally fabricated connection of the upper and lower column,beam and column.%为深入研究装配式梁柱内套筒组合螺栓连接节点力学性能,进行了3个十字形1/2缩尺比例节点试件在低周往复荷载作用下的试验研究,对节点的破坏模式、滞回性能、刚度退化、节点核心区剪切变形、弯矩-转角关系曲线等进行了分析.研究结果表明,在低周往复荷载作用下节点的破坏模式主要表现为对穿螺栓被拉断,外伸端板屈曲,柱壁凹屈,柱壁间连接焊缝断裂;上段柱对穿螺栓往复滑移造成的塑性变形集中在柱壁及外伸端板区域并形成塑性铰,节点具有一定的耗能能力,受对穿螺栓贯穿柱壁连接效应影响,在往复荷载作用下出现“对称凹屈”现象;随内套筒厚度增加,节点核心区剪切变形减小,抗剪刚度增加;节点具有一定的转动刚度,表现出半刚性节点性质.提出的装配式梁柱内套筒组合螺栓连接节点可以实现上柱与下柱、梁与柱全装配式连接.
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