Research On Structural Optimization Design Of Large Cantilever Light Steel Roof

With the development of economy,material innovation and advancement in science and technology,due to the actual needs of large-scale exhibitions and sports events,there are a large number of public buildings of various forms,spans and longer cantilever.The appearance of these structures put forward higher requirements on the design and construction technology of the space structure,especially in the aspects of structural selection,safety and stability,and key nodes.However,China's regulations can not fully meet the design requirements of such projects at present.Because the design theory and methods are relatively backward,steel structure design often has problems such as unreasonable design and excessive engineering cost.This article relies on the actual project to study the structural selection,safety and stability,and key nodes in the design process of the light steel roof structure composed of large cantilever.These studies have a great significance of engineering practical value.(1)Structural Selection and Optimization Design: Relying on practical projects,different types of cantilever truss schemes,different height truss schemes,and different floor spacing programs were proposed.The three factors of architectural modeling,material utilization,and economics were analyzed and studied.Finally,a model with elegant design,excellent performance,and economical application was selected.(2)Structural stability analysis: Stability is an important part in the design of space bar structure.This paper uses the large finite element analysis software ABAQUS to analyze the stability of the whole structure and single truss.The result shows that the overall performance of the type selection program is good and meets the requirements of the specification.(3)Structural wind load response analysis: The roof structure has the characteristics of light weight,flexibility,and low damping.The wind load is one of the control loads for structural analysis and design,and it will have a great impact on vertical deflection.In this paper,the equivalent static wind load determined by the canonical scheme and the wind tunnel test method is used to calculate,and the deflection obtained by the standard method is found to be larger,and the wind tunnel test method is more realistic.(4)Key node finite element analysis: There is no corresponding design method in the specification for multi-tube intersecting nodes and pin connection nodes.In this paper,finite element analysis is performed on these two typical nodes,and the recommendations of the local reinforcement of the upper and lower ear plates where the intersecting nodes join the inner ring and the pin shaft at the intersection of the webs are proposed.