Earthquake Mitigation Effect Analysis Of A New Recentering SMA-steel Slit Damper

Although the steel slit dampers commonly utilized for aseismic design approach can dissipate considerable energy created by the yielding of base materials,large residual deformation may happen in the entire frame structure.After strong external excitation,repair costs will be incurred in restoring a structure to its original condition and to replace broken components.For this reason,in this paper,the shape memory alloy(SMA)bars with intelligent recovery performance is added to reduce the damage of the steel slit damper.A new type of recentering SMA-steel slit damper is proposed to reduce the residual deformation,and the structure can be restored to the original position after the earthquake,which can reduce the damage to the original structure.First of all,on the basis of the existing steel slit damper test,the ANSYS Workbench nonlinear finite element method is used to simulate and analyze the steel slit damper.Secondly,according to the Auricchio constitutive model,the stress-strain curve of SMA bar was simulated by the finite element method,and coMPared with the existing test results,the superelastic property of SMA bar was studied.Then,on the basis of previous research,put forward a new type of recentering SMA-steel slit damper,introduces the structure and working principle,and the finite element simulation results and main influencing factors of recentering SMA-steel slit damper is analyzed in detail.Finally,the proposed recentering SMA-steel slit damper is applied to structural vibration control.To investigate the damping performance of the damper,the nonlinear time history analysis of the steel frame and the steel frame with recentering SMA-steel slit damper is carried out under the condition of three groups of rare earthquakes,respectively,by SAP2000.The results show that the mechanical model of the recentering SMA-steel slit damper is reasonable by the restoring force model of the steel slit damper and the restoring force model of the superelastic SMA bars.Compared with the traditional steel slit damper,the recentering SMA-steel slit damper has a higher energy consumption level and recentering capability,the maximum recovery rate was about 88%.The new recentering SMA-steel slit damper has a good aseismic performance in nonlinear time history analysis,and it can return to its initial position after the earthquake,which can greatly reduce the damage to the original structure.