Cable Parameter Research Of Cable-supported And Knee-braced Steel Frame

Along with the economic development, the application of the light portal steel frame is more and more comprehensive,its demand is increasing. When the light portal steel frame need a higher request in span and economy of industrial and civil construction, the old no longer meets the requirements. The cable-supported and knee-braced steel frame solves the problem of a certain extent. In the design of the structure, parameter analysis is the key problem.In this paper,the characteristics and classification of prestressed steel structure are summarized, on the basis,introducing domestic high-profile examples of engineering application of prestressed steel structure. The research of prestressed steel structure at home and abroad are reviewed and summarized,and introducing the research contents in this paper.Based on the deformation of the structure,the cable system parameters was studied.Finally the cable parameters of the single cable system and the cable-supported and knee-braced steel frame are summed up.The main research in this paper follows:String supported beam and knee braced system under the vertical uniformly distributed load and horizontal wind are respectively researched. Based on its internal force and deformation characteristics,determining the expectation effect of cable,and on the basis of the effect, the rule of cable parameters is established. String supported beam system should comply in the rule that the deflection of beam reach at target under the vertical loads.The upper and lower cable of knee braced system should follow different rule on the characteristics of deformation and initial force. Upper cable complies in the rule that under the suction of wind, structure deflection reaches the design target and the strength of cable is made full use.Lower cable complies in the rule that under horizontal load, the lost initial force of compression cable equals to the initial prestress.Based on the simplified model of deformation of the structure,and according to the structure deformation superposition principle and the rule of cable parameters,establish parameters prediction theory.Based on simplified model, considering geometric non-linearity, analyzing the structural response in the process of loading by the finite element software SAP2000, in order to verify the theoretical results and probe into the theoretical deviation correction.Finally proposing the design suggestions for the cable-supported and knee-braced steel frame so as to provide guidance for the actual engineering that has been built.