Resilient performance of super-elastic SMA bolted connection equipped with extended end plate and shear tab

Abstract

In this paper, a new kind of SMA bolted connection equipped with extended end plate and shear tab (SMA-EP-ST) was proposed, and the resilient performance of end plate bolted connection (SMA-EP) and SMA-EP-ST, were numerically investigated. It is found that both SMA-EP and SMA-EP-ST have good energy dissipation and self-centering performance, and both of them exhibit semi-rigid and partial-strength behavior. In addition, SMA-EP-ST has higher strength, stiffness and ductility than SMA-EP, indicating that SMA-EP-ST can utilize the superelasticity of SMA to a greater extent. To further optimize the design parameters of SMA-EP-ST, a parametric study was carried out to examine the influence of SMA bolt pre-strain, length-to-diameter ratio, and the end plate thickness on the resilient performance. Finally, the mechanical model of SMA bolted connection was established to analyze the force of the thread, which was calculated by using the thread deformation theory of Yamatoto. A design method considering the thread force was proposed and evaluated, which can design SMA bolts with different forms of bolted connections and avoid premature failure at the thread.