Study On The Design Theory And Experiment Of Buckling-restrained Braced Concrete Frames

Buckling-Restrained Brace Concrete Frame(BRBCF)has better effect on damping than the traditional bracing frame owing to its Buckling-Restrained Brace(BRB)can resist buckling when suffer to compression.BRB is used as the "first line of defense" in seismic fortification,which plays a role in protecting the column and beam in BRBCF.On one hand,BRB is less applied in concrete structures,while the construction of new buildings is still dominated by concrete structures in China.It is a point of BRB damper research that how to make the BRB give priority to the function of the energy consumption in earthquake so that the overall framework of the yield mechanism is reasonable(BRB,beam and column yield in turn).Therefore,the main research contents of this article including the following parts:(1)The mechanical model of BRB and analytical method of BRBCF are determined.The pushover analysis for a cross of BRBCF is carried out using SAP2000.The lateral stiffness ratio k between the buckling-restrained braces and frame is introduced as the main control parameters.(2)To achieve a reasonable yield mechanism,a practical design ideas for BRBCF is proposed by the spreadsheet.Trial design is applied to framework among different lateral stiffness ratio(k=0.25,0.5,0.75,1.0...5.0)to verify the feasibility of design ideas.A preliminary range of k is put forward.(3)The time history analysis(including frequently and rarely occurred earthquake)for a cross of BRBFC which is among the suggested range of k is carried out in order to optimization the ranges of k.Then the applicable scope of the lateral stiffness ratio is obtained against different frequently and rarely occurred earthquake.(4)Basing on the former research of this paper,a 1/2 reduced scale flat monolayer single-span frame specimens is designed(including design of frame joints,embedded parts and gusset plate).A cyclic loading test is carried on BRBFC for seismic research in order to verify the feasibility of design ideas in practice.In this paper,the study on design theory and experimental provide an important reference for the research and engineering practice about full-scale multilayer multi-span frame a.