Experimental And Theoretical Analysis On Seismic Behavior Of Buckling Restrained Braced Precast Concrete Frame

Precast concrete frame(PCF)is one of the main forms of precast concrete structure of construction industrialization.PCF has advantages of rapid construction speed,less pollution at construction site,less labor cost and green environment protection.However,high construction accuracy requirements the precast beams and columns are assembled on site,which leads to the seismic performance of beam-column joints are usually poor and limit of the building height and the application scope of PCF.Buckling restrained brace(BRB)could yield in both tension and compression without buckling.BRB also possesses high bearing capacity,good ductility and excellent energy dissipation capacity under cyclic loading.At present,it has been widely used in the new buildings and reinforcement project.The usage of BRB can effectively improve the seismic performance of PCF.At present,studies of buckling restrained braced precast concrete frames(BPCFs)are less.With a series of experiments and theoretical analysis,this dissertation does research on seismic performance of PCF with BRB.Main contents include:(1)A single-span cast-in-situ reforcement concrete frame(RCF)and four single-span PCFs with BRBs were conducted under seismic load.The main study parameters included: the type of beam-column joints,embedded parts type,the layout of BRB layout and the setting of BRB.The hysteresis behavior and failure modes of RCF and PCFs with BRBs were discussed and compared on the basis of different research parameters.(2)The seismic performance of one RCF and four PCFs with BRBs was evaluated in terms of skeleton curves,strength and stiffness degradation,ductility,and energy dissipation,etc.The law of strain variation and yield order at the key parts of all specimens were also analyzed emphatically.(3)Five finite element(FE)models of RCF and PCFs with BRBs were respectively established by software ABAQUS.The monotonic horizontal load(P)– displacement(?)curve was acquired from numerical analysis and validated by tested resulted.Furthermore,the non-liner whole-course analysis were carried out to obtain the mechanical mechanism of five FE models.(4)Simplified FE model of PCF with BRB were developed and discussed.The load parameters,material parameters,geometric parameters and the parameters of BRB were used to analyze the typed frame structure systematically.The important parameters and influencing laws on horizontal load(P)– displacement(?)curve were obtained.