Experimental Studies On Seismic Performance Of The Energy-Dissipative Buckling Restrained Brace Steel Frame Structure

In this thesis, searching the design of BRB energy dissipation and focus on the selection problem of stiffness. based on the finite element simulation and experiment, it can give the reference for the project conclusion. Using the conventional method to design the framework and components of the conventional steel frame, BRB and the gusset plate, and combining the purpose of study to design 2 and 3 stiffness ratio of the steel frame. After the design of test model, conducted the quasi-static test for stiffness ratio of 2 and 3 of BRB member. examined the energy dissipation and elastic calibration of ratio between strain and the axial force, extracted the restoring force model of the BRB, for engineering analysis. 4 frame models were initially analyzed in ABAQUS before the experiment, respectively verify the impact of the gusset plate on the frame properties. Analysis of the damage and the overall performance of the BRB framework, including the bearing and energy dissipation capacity. Obtained by comparing the seismic performance is more excellent framework that provides a reference framework for the follow-up frame test. Last, do the pseudo static test of framework and get the damage of the two stiffness framework, this thesis analyzes the framework of basic mechanical parameters and the energy consumption index, combining the performance obtained excellent relative stiffness ratio.Through the quasi-static test of two kinds of stiffness ratio of the buckling restrained brace, in the core plate of BRB is finally pulled and broken, The sleeve bolt is connected without local buckling, and the bolt spacing can ensure the integrity. The hysteresis curve of the support shaft is symmetrical distribution, full smooth without mutation, the component's stress is uniform, energy dissipation is stable and excellent, and the fatigue performance is excellent. The ratio coefficient of support axial force and strain was obtained, the Sr2 APB and Sr3 APB coefficients were 0.31 and 0.34, in order to measure the BRB axial force.In the simulation of steel frames, verify the impact of the gusset plate on the frame stiffness and overall performance, analysis shows that :(1) with the gusset plate steel frame stiffness was significantly higher than frame, improve 13.91%, the bearing capacity decreased slowly compared to the frame, delay the destruction of the node domain;(2) stiffness ratio of 2 and 3 bearing capacity were higher than that of the frame and high structure ductility, as 47.05%? 70.86%;(3) stiffness ratio of 3 Sr3 BRBSF gusset easy to lose stable, recommended stiffening process;(4) Sr3 BRBSF extent of the damage and the maximum stress in all 4 models are the smallest and the carrying capacity is still under the rising trend in the 1/50(36mm) layer displacement angle, and the comprehensive performance is the best.Do the quasi-static test of Sr2 BRBSF and Sr3 BRBSF, studying the difference between the two kinds of stiffness ratio in the final damage degree and the failure mode, comparing the difference between the two indexes shows that :(1) according to the ratio coefficient of the two frame are the theoretical error of 10% or less, the BRB hysteresis curve is close to the component test, and the method is feasible;(2) the initial stiffness and yield point of two frameworks are the theoretical error of 10% or less, and the theoretical calculation is reasonable;(3) in the final gusset plates of two stiffness frame appears outer surface unstable failure, the outer surface of the gusset plate rigidity still can not meet the requirements in the earthquake should be appropriate to the stiffener connections;(4) the energy consumption index and ductility factor can be concluded that there is a BRB frame with high energy dissipation coefficient and good ductility;(5) Sr3 BRBSF provides not only higher lateral stiffness, but also the energy dissipation and maintain the same level of Sr2 BRBSF, and the beam and column stress is smaller, so Sr3 BRBSF relatively better performance, you can increase in BRB stiffness when the design that can not satisfy the stiffness.