Numerical Analysis Of Seismic Performance Of L-shaped CFST Column-steel Beam Joints Connected By Side Plates

The shaped pipe concrete structure has the advantages of avoiding interior columns protruding from the wall and improving the room arrangement,which is a structural form with good application prospects.However,there are not many studies on shaped steel pipe concretesteel beam nodes,and few studies on shaped steel pipe concrete-steel beam frames have been reported.Therefore,this paper proposes a new node based on the existing node form,and analyzes it numerically by finite element software ABAQUS,and meanwhile further explores the seismic performance and seismic response of the shaped steel pipe concretes-steel beam frame structure,with the main components and conclusions as follows:(1)based on the design principle of "strong node,the weak component",nine node refinement model is established,by the thickness of the length of side panel,side panel,side panel,side panel type and no axial pressure ratio as the main parameters,by observing the damage form of node under cyclic load,the seismic performance indicators of the node is analyzed.Results show that there are side panel node destruction form of the beam end plastic hinge damage,good seismic performance indicators of node;Without the destruction of the side panel node form for the node domain of core damage,hysteretic curve appear obvious shrinkage effect.(2)On the basis of the seismic performance analysis of the strong node,a weak node model with the same parameters is established to clarify the whole process of node transmission and damage,and the corresponding bearing capacity under shear formula is proposed.The results show that the damage form of the node all belongs to the node core shear damage,and the tensile and compressive stresses transformed by the bending torque on the steel beam flange are transmitted in the node core along the opposite diagonal direction.(3)Based on the analysis of seismic performance of nodes,a model of shaped Steel Pipe Concrete Column-Steel Beam Frame is established to study the force mechanism and seismic performance of the frame,and the influence characteristics of the factors with and without side plate on the seismic performance of the frame are analyzed.The results show that the damage of the frame-with-side plate is in the form of plastic hinge damage at the beam end,which meets the seismic requirements;the damage of the frame-without-side plate is in the nodal region of the beam-column node,which cannot meet the seismic design requirements.(4)the special-shaped concrete-filled steel tube-steel beam frame structure modal analysis and elastoplastic time history analysis of frame structures have been obtained respectively in the presence of side panel under the influence factors of natural vibration period and frequency,the dynamic characteristics parameters,such as frame structure is studied in more than seven degrees,the dynamic response under severe earthquake.Results show that compared with no side plate frame,considering the lateral plate connection under the seismic action of the framework of seismic force and displacement response is smaller,the safety of the frame structure is higher.