Finite Element Analysis Of Shear Connector Of New Type Of Assembled Steel-Concrete Composite Beam

In order to meet the needs of the assembly development of steel-concrete composite beams,this paper proposes a new type of fabricated composite beams using high-strength bolts as shear members.Since the bolted joint is the key component to ensure the cooperative work of the composite beam,in order to understand the shear resistance of the joint,the finite element model of the test specimen is established based on the large-scale general finite element software ABAQUS,and the influencing factors of the shear ultimate bearing capacity are studied.In addition,through the establishment of a new type of assembled composite beam finite element model,the influence of the degree of shear joint and the strength of concrete on its bending performance is explored,which provides reference for future experimental research and application.The main work and conclusions are as follows:(1)The structure of the new assembled composite beam is introduced in detail,and it is compared with the traditional composite beam.The comparison results show that the advantage of the composite beam is that it can realize complete assembly construction,so that is conducive to cost saving;and,considering all components can be factory prefabricated,the quality can be effectively guaranteed.(2)The finite element model of Push-out Test of the bolt joints in the new type of assembled composite beam was established by ABAQUS,and the influence of bolt diameter,bolt spacing,bolt quantity and concrete strength on the shear performance of the joint was investigated.The research results show that the ultimate bearing capacity of the bolted joint increases with the increase of the bolt diameter;increasing the bolt spacing can increase the ultimate bearing capacity of the joint to a certain extent;increasing the number of bolts can increase the ultimate bearing capacity of the bolted joint,but the ultimate bearing capacity does not increase proportionally with the increase in the number of bolts;what's more,the strength of the concrete does not significantly affect the ultimate bearing capacity of the joint.(3)The elastic and plastic design theory of composite beams and the design method of shear connectors are introduced in detail.On this basis,a new type of fabricated composite beams is designed and the bending capacity of the composite beams and the number of connectors are calculated by plastic theory under full shear connection.The calculation results show that when the full shear connection is reached,the number of new assembled bolt connectors required is much smaller than that of the traditional stud connectors,and the new connector is more economical.(4)According to the design of new assembled composite beam,the finite element model of that is established by ABAQUS,and the influence of the degree of shearing resistance of shear joint and concrete strength on the bending resistance of the composite beam is explored.The research shows that the improvement of the degree of shearing resistance of shear joint can reduce the slip of the interface of the composite beam and improve its capacity of bending resistance;yet,the strength of concrete has little effect on the bending capacity of the composite beam and interface slip.