Experimental Studies On Seismic Performance Of The Energy-dissipative Buckling Restrained Brace Reinforced Concrete Frame Structure

Buckling Restrained Braces, set in the structure, can provide lateral stiffness to structure and use its lag after yielding to absorb seismic energy structure which make structure get a good performance dissipation and reduce the damage degree of the structure under earthquake action. The existing design methods of the buckling restrained braces of the buckling restrained brace reinforced concrete frame, can realize that buckling restrained brace yield and consume energy before the main structure, which meet the seismic fortification requirements of the first line of defense. When designing the buckling restrained brace reinforced concrete frame, usually start with the assumption that assuming the stiffness of the buckling restrained braces, and use it to calculate the maximum allowable yield force and continue the design of the other part of the buckling restrained braces. Which stiffness of the buckling restrained braces is the best, there is no standard at present. The buckling restrained braces with two kinds of stiffness and reinforced concrete frame are the research object of this paper. Through the simulation experiment and a construction project sumulation, study how buckling restrained energy dissipation braces of frame structure affect beam column joint, ductility, hysteresis performance, nonlinear performance, the overall framework yield sequence under the action of earthquake, when the lateral stiffness ratio(also known as the "SR", the same below) of the buckling restrained energy dissipation braces and reinforced concrete frame are 2.0 and 3.0.The main research contents and conclusions are as follow:(1) Summarizes the current domestic and foreign study onbuckling restrained energy dissipation braces and the buckling restrained brace reinforced concrete frame, put forward a experiment for the buckling restrained energy dissipation braces reinforced concrete frame in two different lateral stiffness ratio.(2) Design and produce the buckling restrained braces in two kinds of stiffness respectively and two one-story-one-span reinforced concrete frame structurewith the same size. After the installation of the buckling restrained braces, the Sr of the framesare 2.0 and 3.0, respectively.(3) Having Pseudo-static low reversed cyclic loading experiment on the buckling restrained braces reinforced concrete frame structure in Sr2.0 and Sr 3.0 respectively, study how buckling restrained braces of frame structure affect beam column joint, ductility, hysteresis performance, nonlinear performance, skeleton curves, the overall framework yield sequence etc. The results show that the buckling restrained braces reinforced concreteunder two kinds of lateral stiffness ratio both has good integrity and good energy dissipation.Compared that in smallstiffness,buckling restrained braces in large stiffness will bringgreater load burden to beam-column node.(4) Based on the component performance parameters and test data, using PKPM software, Etabs software and Perform–3D software, have adynamic elastic and elastic-plastic time history analysis for a 6-story reinforced concrete frame structure,including its original structure and two different stiffness BRB application form(Sr2.0 and Sr3.0). Analysis results show that the application separately installed two different kind of stiffness buckling restrained braces structure can improve the original structure whick does not meet the specification requirements, and showed good seismic performance and energy dissipation performance. Under similar seismic target under the premise of structure, compare with the Sr3.0 BRBF structure, the buckling restrained braces of Sr2.0 BRBF structure make the additional shear for the column smaller and stiffness of each floor more balance.