Abstract:
A novel self-centering shape memory alloy slip friction damper (SMASFD) is proposed by combining shape memory alloy (SMA) bolts and friction interfaces of grooved plates. This paper introduces the configuration and working mechanism, the theoretical equations, the proof-of-concept test, and a finite element (FE) model of the damper. The result shows that the damper with an appropriate design of the groove angle and friction coefficient has flag-shaped hysteresis, which indicates good energy dissipation capacity and excellent self-centering capability. Both the analytical prediction and the simulation results agree well with the experimental data. A parametric study is carried out based on the verified FE model. Six additional models are established. The key parameters include the groove angle, friction coefficient and preloading of SMA bolts. The results indicate that: the nonlinear deformation is concentrated in the SMA bolts, and the other components remain elastic; increasing the groove angle will increase the strength capacity, secant stiffness and energy dissipation; the energy dissipation capacity increases with the increase of the friction coefficient, but the self-centering capacity will be lost if the friction coefficient exceeds the upper limit; preloading the SMA bolts enhances the initial stiffness and secant stiffness, but it reduces the deformation capacity of the damper.