Finite Element Analysis On Seismic Behavior Of T-shaped Concrete-Filled Steel Tubular Webs Penetrating Joint

Special-shaped concrete-filled steel tube is formed through continuous development of concrete structure of concrete filled steel tube.It has been widely recognized in some actual project due to its great advantages.Such as high strength of its core concrete,high ductility and its same thickness with walls without prominent.What's more,it can be used in some place where is High seismic fortification intensity and high rise buildings.In recent years,domestic and foreign experts study a lot on special-shaped concrete-filled steel tube beam-steel beam joints.Few on special-shaped concrete-filled steel tube concrete beam joints.So this article based on the existing research studies the Seismic performance of T-shaped concrete-filled steel tubular column-concrete beam and steel beam web penetrating joints.he main research content and achievements are as follows:(1)using ABAQUS--the finite analysis software established 9 T-shaped concrete-filled steel tubular column-concrete beam web penetrating joints through the Major change parameters of Corner length,axial compression ratio,penetration plate thickness and steel pipe wall thickness.established 9 T-shaped concrete-filled steel tubular column-steel beam web penetrating joints through the Major change parameters of Axial compression ratio,penetration plate thickness,steel flange thickness,steel pipe wall thickness.The hysteresis curves of each node are obtained by monotonic loading and reciprocating displacement loading,and their ductility and energy dissipation,intensity degradation and stiffness degradation are analyzed.The analysis shows that the hysteresis curves of the two types of nodes are full,the stiffness and intensity degradation of the nodes are stable and the seismic performance is superior.(2)By analyzing the stress-strain cloud diagram of two kinds of nodes,the crack propagation process and the model shear stress variation of the two types of nodes are analyzed.The results show that the failure of the concrete beam web penetrating the joints is carried out through the beam The bearing capacity of the joint model is reduced rapidly,and the failure mode of the steel beam web penetrating the joint is the flange buckling,and the steel pipe wall is torn and torn.(3)The influence of the variation parameters on the performance of the nodes is analyzed by skeleton curve,intensity degradation curve,stiffness degradation curve and ductility and energy dissipation coefficient.The results show that,due to the large difference in beam and column stiffness,The ductility of the nodal model is slightly improved,but the influence of other properties is limited,and the increase of the length of the bark increases the ultimate bearing capacity of the concrete beam web through the node,and the maximum capacity reaches 23.87%,while the energy dissipation capacity is reduced.The increase of the thickness increases the initial stiffness of the two kinds of nodes,and the ductility and energy dissipation coefficient of the steel beam are improved,and the ductility and energy dissipation coefficient of the concrete beam are reduced,which is due to the difference of the two kinds of nodes The The increase of the wall thickness increases the ultimate bearing capacity and the initial stiffness,and the ductility and energy consumption are improved.The flange thickness is positively correlated with the ultimate bearing capacity and negatively correlated with energy dissipation and ductility.