Research Of Resilient Deformation Performances Of Replaceable Buckling-restrained Brace System Based On Shape Memory Alloy

The traditional buckling restraint brace(BRB)is generally composed of two parts: the core element and the restraint element.The core element generally chooses low yield point steel,which is the core part of BRB,which mainly bears the axial load;the restraint element mainly includes two restraint forms of concrete restraint and pure steel restraint.However,the traditional BRB still does not get rid of the shortcomings of relying on improving the structural rigidity to enhance the seismic resistance of the structure.The residual deformation after a strong earthquake is still large,which affects the maintenance and continued use of the structure.Therefore,properties such as toughness,replaceability and high energy consumption have become the focus of the new BRB research and development,and certain results have been achieved.(1)In order to solve the problems of the above traditional BRB components,this paper starts with the basic theory of traditional BRB,and studies the basic theory of traditional BRB.Then proposes a new type of BRB based on the toughness and replaceable of superelastic(shape memory alloy)SMA,and proposes specific design indicators and design methods based on displacement.(2)Using ABAQUS to verify the traditional BRB model,propose a traditional BRB simulation method based on ABAQUS,and use this method to simplify the modeling design of the new BRB to form a finite element modeling method for the core section of the new BRB.Through the pseudo-static analysis of the traditional BRB and the new BRB,it is verified that the new BRB has better hysteretic energy consumption and self-reset ability than the traditional BRB.(3)The parameter analysis of the new BRB component is carried out,and the influence of the gap size on the performance of the new BRB component is obtained,and the contact change and stress state of the external restraint component are analyzed.The new BRB components are added to the frame system,and ABAQUS is used to conduct a quasi-static analysis of the new BRB frame system to verify that the new BRB frame system has a good self-reset ability.The main contribution of this paper is to use super-elastic SMA angle steel as the new BRB core component to provide greater restoring force and hysteretic energy dissipation capacity,and to use the replaceable form of the core component to improve structural toughness performance...