Performance Analysis For Concrete-Filled Circular Steel Tubular Connection Of Diagrid Structures

Diagrid structural system is an innovative structural system,which combine the architectural aesthetics and the structure perfectly and has been more and more application in the high-rise building.But its theoretical research is far behind the practical application of engineering,especially on the node research in the oblique grid system.The most important thing is how to solve the mechanical performance and construction of beam-column joints.Therefore,based on the previous research results,the static and seismic performance of the beam-to-column structures in the oblique grid structure are studied,and some parameter values for structural design are proposed.This papers mainly studies the following aspects:1.The behavior of each members of a diagrid-frame core tube structure of the overall modeling under different load combined are analyzed by SAP2000,especially the axial force of oblique column combined the node,the cycle of the structure,the lateral displacement of the top layer and the size of the interlayer displacement angle of each layer.When the structure combine the ring beam or not,the influence of the structure on the structural performance is analyzed and compared,which lays the foundation for the later research.2.In order to study the seismic performance of the intersecting connection under axial loads.A series of nodes with different oblique angle and thickness of steel were analyzed by ABAQUS.The influence of these parameters on the seismic performance of the joints is analyzed by changing the angle of the oblique column,the thickness ratio of the steel pipe and the thickness of the elliptical connecting plate.3.In order to improve the performance of the node,the paper puts forward the new form of the concrete cross-section welded pipe of the diagrid system,which is based on the form of the original node proposed by Han Xiaolei and others.The ABAQUS finite element software was used to analyze the bearing capacity and the seismic performance of the node.The bearing capacity and the seismic performance of the two kinds of structural joints are analyzed and compared.The results show that the bearing capacity of the modified node is increased by 9%,the ductility is increased by 12% ~ 38%,and the normalized energy consumption is 2%~31%.