Seismic Performance Analysis Of Steel Frame-Cross Buckling Restrained Brace Structure

Because of the advantages of lightweight and high strength, rapid construction and flexible arrangement of space, the steel structure has been widely used in the engineering construction. However, the pure steel frame structure with good ductility and relatively smaller cross section usually can’t meet the requirements in lateral stiffness and deformation. Frame-braces system is commonly used to supplement the inadequate of lateral capacity of pure frame structure. Ordinary steel braces are prone to occur compressive buckling and quit work under severe earthquake, which resulted in the seismic capacity of the whole structure declining sharply until destroyed.In recent years, the buckling restrained brace system of China has been studied and applied more widely. Due to the special structure in elastic stage buckling restrained braces can provide the lateral stiffness of the structure,and can be achieved the elastoplastic yield without the full cross-section buckling. But there is no clear scientific research and conclusions on the overall structure of the anti-lateral stiffness,and other seismic performance of buckling restrained braces. Our buckling restrained braces for research and application is still in its infancy, and its important role to play in the actual project is still not clearly reflected.This paper based on the actual Ningxia sports schools and sports training center relocation project management comprehensive training hall, through the finite element software simulation, analysis,buckling restrained mechanical properties of the support member, and compare analytical framework,ordinary steel steel frame and steel supporting structure frame -buckling restrained braces structure three forms of structural seismic performance.Details are as follows:(1) Describes the buckling restrained braces said construction principles and engineering applications, and research status buckling restraint support member and the frame system are summarized. Analyzed the works, strength requirements,stability and influencing factors of the buckling restrained braces theoretically.(2)Analyzed the use of software ABAQUS for buckling restrained hysteretic performance member, the maximum tensile stress at different strain, stiffness, and energy dissipation capacity equivalent viscous damping ratio .. through the calculation of stifffness, obtained before yielding stiffness and length and area, K1 =154.12A/L,and post yield stiffness coefficient of variation is small, the desirable average 0.0382 to engineering example simulation provides post yield stiffness coefficient. The relationship between the equivalent viscous damping ratio and the axial strain amplitude is firstly increased, and then tends to be stable, which changes little after strain 1%. The average value of the equivalent viscous damping ratio is 0.522, which can be stabilized after calculation, which can provide reference for the equivalent viscous damping ratio in the case engineering.(3) In accordance with the seismic design code, used the software SAP2000 to analysis steel frame and steel frame supporting multicase model under earthquake response spectrum, and the natural cycle, angular displacement between the interlayer and the shear layer comparison; then use SAP2000 to analysis model steel frame, steel frame supporting common model,steel frame buckling restrained braces model under the process of an earthquake. The structure of the interstory drift, interlayer shear, displacement-time curve of the top base shear duration curves were analyzed.(4)Summarize the beneficial effects of buckling constraints and performance characteristics of the support structure to produce and make a prospect.