组合楼板对装配式钢框架节点抗震性能的影响

为了解决装配式钢框架中节点区域构造复杂和传力机制不明的问题,提出一种考虑组合楼板作用的端板螺栓连接节点。设计并制作了2组端板连接的装配式梁柱节点,进行了低周往复循环荷载试验,建立了节点试件的数值模型,分析组合楼板对节点的破坏模式、滞回性能、承载能力、半刚性性能、受力特征的影响作用。结果表明,端板连接节点主要破坏模式为端板的弯曲变形,组合楼板的加入会使滞回曲线产生一定的捏拢现象,同时会产生组合楼板开裂破坏现象;增加组合楼板后,端板连接节点的初始转动刚度、极限承载力、耗能能力分别增加了约22%,13%,22%;组合楼板和钢梁上翼缘共同作用时,荷载通过组合楼板传递至柱腹板;与闭口型压型钢板-混凝土组合楼板的节点相比,采用开口型压型钢板-混凝土组合楼板的节点初始转动刚度和极限承载力分别提高13%和9%。组合楼板能有效提高端板连接节点的抗震性能,扩大节点核心区的传力范围,增强梁柱传力机制,可为进一步提高装配式节点性能提供参考。

Influence of composite slab on seismic performance of prefabricated steel frame joints

To solve the problems of complex structure and unclear force transfer mechanism of joint area in prefabricated steel frame,a bolted end-plate joint considering composite slab was proposed.Two groups of prefabricated beam-column joints with end-plate connection were designed and manufactured,and the low-cyclic loading test was carried out.The numerical model of joint specimens was established,and the influence of composite slab on failure mode,hysteretic performance,bearing capacity,semi-rigid performance and stress characteristics of joints were analyzed.The results show that the main failure mode of the end-plate connection joint is the bending deformation of the end plate,and the addition of the composite slab will make the hysteretic curve pinch to a certain extent,and at the same time,it will cause the cracking failure of composite slab.After adding the composite slab,the initial rotational stiffness,ultimate bearing capacity and energy dissipation capacity of the end-plate connection joints increase by about 22%,13% and 22%,respectively.When the composite slab and the upper flange of steel beam work together,the load is transferred to the column web through the composite slab.Compared with the joint of closed profiled steel sheeting-concrete composite slab,the initial rotational stiffness and ultimate bearing capacity of the joint with open profiled steel sheeting-concrete composite slab are increased by 13% and 9%,respectively.Therefore,the composite slab can effectively improve the seismic performance of end-plate joints,expand the force transmission range in the core area of joints,and enhance the beam-column force transmission mechanism,which provides reference for further improving the performance of prefabricated joints.