Semi-rigid Steel Frame Node Dynamic Analysis And Performance Optimization

In the traditional steel frame design, beam-column joints are generally seen as completely rigid or hinged, which is to simplify the design process and the results of the analysis of the beam-column joints. But in the actual engineering, if only considering the rigid connection, is to exaggerate the performance of the node constraint; if only consider the hinged connection, is to ignore the performance of node constraint. Practice shows that engineering is semi-rigid nodes, its performance between rigid and hinged connection, under load, can pass a certain moment and produce some deformation, in fact is semi-rigid nonlinear deformation, deformation of this kind of change in the response characteristic of the structure. Its influence on the mechanical behavior of steel frame is very important, because of the semi-rigid nodes with strong deformation and energy dissipation capacity, in under the action of earthquake resistant to certain seismic load. So we at the time of steel frame design and analysis, to consider the effect of semi-rigid nodes of structural mechanics. This article mainly studied the high-rise steel frame structure in a rigid connection and semi-rigid connection of base shear and lateral displacement analysis contrast, and under the condition of semi-rigid nodes do not accord with standard of the various kinds of optimization.This paper briefly describes the status of semi-rigid connections at home and abroad, the basic theory, types and characteristics of the connection and the moment-rotation curve of semi-rigid connections, and then with calculation method for rigidity of the end-plate connected to the compute nodes of the initial rotational stiffness. Finite element analysis software SAP2000 to establish rigid connection and semi-rigid connection framework model, modal analysis was carried out on the steel frame respectively, response spectrum analysis, and in both the time history analysis under earthquake loads. Calculation results:connect the semi-rigid according to rigid connection, caused great error for the seismic design, so in the design of flexible connection cannot be neglected when the impact of dynamic performance of the structure, namely to consider the influence of the spring joint. When using rigid connection of steel frame structure of the lateral displacement meet the requirements of specification, and the software was used to simulate the semi-rigid connection steel frame, its displacement than the specification requirements. Therefore the situation of semi-rigid connections to optimize the design, one is changing the stiffness of the nodes, and the second is between the beams were increased bracing, change the overall stiffness of the steel framework.Finally, the conclusion and semi rigid steel frame work put forward the prospect and provides reference for future design of steel structure engineering significance.