Hysteretic Behavior Analysis Of A Novel SMA-friction Damper And Seismic Performance Analysis Of Large-span Spatial Structures

Large-span spatial structures,as the advantages of large space,light weight,good ductility,etc,have a wide application in public buildings,such as gymnasiums,airport terminals and convention and exhibition centers.Large-span spatial structures may generate large vertical responses under earthquakes,causing structural damage or even collapse.The traditional seismic design of the structure relies mainly on increasing the strength and deformation capacity of the structural members themselves to resist earthquakes.Due to the randomness of the earthquake,the method is neither economic nor safe.The installation of dampers at certain critical locations of the structure can effectively alleviate the seismic response of the structure.Shape memory alloy(SMA)is a new type of material with superelastic properties.It can be used to develop highperformance energy-dissipation dampers,which have a good application prospect in large-span spatial structure vibration control.In this context,this paper develops a new SMA-friction damper and carries out its hysteretic behavior by experimental research and theoretical analysis,and then carried out the seismic performance analysis of largespan spatial structures.The main contents of this paper can be shown as follows:(1)The experiments on SMA wires are conducted to explore the effects of cyclic loading times,loading rate,strain amplitude and diameter on the mechanical properties of SMA wires.The variation of these factors on the performance of SMA wires is obtained,which provides a theoretical basis for the design of the SMA-friction damper.(2)A novel of SMA-friction damper is developed.The experimental study and numerical simulation of SMA-friction damper are carried out.The nonlinear elastic model and hysteretic model are used to simulate the mechanical behavior of SMA wires.The results show that the numerical model can simulate the hysteresis curve and mechanical parameters of the SMA-friction damper.(3)Parametric analysis of hysteretic behavior of the SMA-friction damper is carried out.The four main parameters of loading frequency,displacement amplitude,number of SMA wires and high-strength bolt pre-tightening force are studied for effect of the hysteresis curve and the mechanical parameters of the damper.(4)The seismic reduction performance analysis of the large-span spatial structures is carried out.The SMA-friction damper is applied to the quadrangular pyramid doublelayer spherical reticulated shell,the beam string structure and the suspen dome structure,the average displacement reduction rate of the apex is 25.81%,31.25% and 18.6%,respectively.The seismic reduction performance analysis of K6 double-layer spherical reticulated shells under different seismic intensities is carried out.Under Kobe waves,the apex displacement reduction rate can reach 56.78%.The results show that the SMAfriction damper shows good ability of energy dissipation and the seismic response of large-span spatial structures can effectively reduce by installing the SMA-friction damper.