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

Abstract

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.[HQ]

Keywords

• structural design; prefabricated steel frame; composite slab; end-plate connection; seismic performance