Seismic Performance Study Of A Self-Centering Buckling Restrained Brace With Disc Spring

As a natural phenomenon,the earthquake has become one of the main reasons for affecting human life because of its huge destructive power.The traditional structural seismic design method relies on the destruction of the main structure to dissipate seismic energy,resulting in large residual deformation of the structure,which is very difficult to continue to use or repair after the earthquake.The energy dissipation measures can effectively dissipate the seismic energy.As a good energy dissipation member,buckling restrained brace is widely used in engineering practice.However,due to the large residual deformation,the support performance is greatly reduced.In order to achieve good hysteretic energy dissipation capacity and restoring capacity of braces,a self-centering buckling restrained brace with disc spring is proposed in this paper,and its seismic performance is studied.The main research contents are as follows:（1）In this paper,a self-centering buckling restrained brace with disc spring is proposed,briefly summarizes the structure form and working principle of the brace.The restoring force model of the self-centering buckling restrained brace is discussed in detail,and the performance evaluation indexes of the self-centering buckling restrained brace are given: residual deformation,energy dissipation coefficient and equivalent viscous damping coefficient.（2）Based on ABAQUS finite element software is used to simulate the self-centering buckling restrained brace with disc spring.Compared with the hysteretic capacity of buckling restrained brace.The parameters of the brace are analyzed from the initial bending,the initial compression displacement of the composite disc spring,the cross-sectional area of the energy dissipation inner core and the friction coefficient between the disc springs.The results show that the initial bending of the brace has little effect on the energy dissipation capacity and selfcentering capacity of the brace;The energy dissipation capacity of the brace decreases with the increase of the initial compression displacement of the composite disc spring,but the residual deformation decreases;The overall bearing capacity of the brace is improved and the selfcentering effect becomes worse when the cross-section area of the inner core is increased;With the increase of friction coefficient between disc springs,the restoring effect of the energy dissipation capacity of the brace increases.Based on ABAQUS finite element software,the frame braced structure is established,and the time-history analysis of BRB frame and SCBRB frame is carried out under the action of three earthquakes.The maximum displacement,interlayer displacement angle and residual deformation of the two structures are compared.The first stiffness,the second stiffness,the initial pre-pressure and the cross-sectional area of core are analyzed.The results show that:compared with the BRB frame,the SCBRB frame has excellent Seismic performance and can effectively control the residual deformation;When the first stiffness is larger,the seismic performance of the structure is better;When the second stiffness is larger,the maximum displacement,interlayer displacement angle of the structure is smaller;The greater the initial pre-pressure,the smaller the residual deformation and the better the structural stability;The maximum displacement and floor angle of the structure decrease with the increase of the crosssectional area of the energy dissipation core.