The Mechanical Performance Of Steel Frame-reinforced Concrete Core Tube Mixed Structures Under Different Connection Modes

In recent years, with the rapid development of social economy and engineering technology advances, complex high-rise buildings in the current countries have been got unprecedented development. Steel and concrete composite structure is made up of steel frame and reinforced concrete core canister, by its unique structure and good seismic performance, it gets rapid promotion in the large space and the high-rise building structure. In the mixed structure, the node connection methods have a great influence on overall mechanical performance, under the different connection ways, the stress of the structure has a bigger difference, so it should be done deepen research on the structure node of each connection.Firstly, the study introduces the development of high-rise mixed structure and the research present situation, summarizes the characteristics of mixed structure, this paper introduces the types of commonly used join points (just answer, articulated, semi-rigid connection) and the characteristics of each node.Secondly, based on the structure model in the project, auther do some analysis to the vertical structure in the elastic stage structure static. Compared the structure under live load distribution, the changes of stress on the structure mode of connection, determine the most unfavorable live load distribution form and the stiffness changes in the relationship between mechanical properties and structural components.Again, using two kinds of lateral horizontal force load model (uniform loading mode and loading mode of the inverted triangle) for the elastoplastic pushover analysis, the structure by the more severe earthquake action and the rarely met earthquake, the node connection on structure performance and the influence of the plastic hinge.Finally, on the basis of above analysis, some conclusions are put forward for the different connections of mixed structure.:1) During the static elastic analysis, the live load across the insulation arrangement to the most unfavorable stress steel beam, steel beam midspan node is connected with the size of the bending moment and inversely proportional to the stiffness;2) The right end girder bending moment is proportional to the stiffness;3) Steel beam at the left is inversely proportional to the bending moment and shear force and stiffness;4)Column at the bottom of axial force is affected by node connection method is small, but the bending moment is inversely proportional to the stiffness at the end of the tube;5)Static elastoplastic analysis, the same connection mode, the displacement under uniform loading way-shear curve in the inverse triangular load curve;6)Under the same load, the base shear is proportional to the stiffness of structure nodes;7)In the structure and the rarely met earthquake performance point displacement and interlayer displacement. Angle is inversely proportional to the stiffness;8) Structure under severe earthquake to damage when node adopt rigid connection, the structure of the overall seismic performance is best. These conclusions are meaningful for these projects and could be provided a certain reference value for the engineering of the node analysis.