Abstract：Using superelastic shape memory alloy (SMA) wire, a re-centring damper is presented. Based on the Graesser’s constitutive model of SMA wire, the slip bilinear restoring force model of the damper is set up. Given that the two models have the same hysteretic areas, a simplified slip rigid-plastic model is put forward to approximate the slip bilinear model. Using an equivalent linearization method, analyses of the stationary random vibration of a single-degree-of-freedom structure with the SMA damper subjected to a Gaussian white noise excitation are formulated. Numerical simulations are carried out, considering various excitation’s spectrum densities and damping ratios of the structure. Comparisons of the vibration responses (displacement standard deviation and velocity standard deviation) of the SMA-damped structure between the equivalent linearization method and the Monte Carlo simulation method testify the validity of the random vibration control theory. Comparisons of the dynamic properties (stiffness and damping ratio) and the vibration responses between the equivalent linearized damped structure and the uncontrolled structure prove that the SMA damper can decrease the structural vibration effectively attributed to its capabilities of increasing the stiffness and the damping ratio of the structure.
2013, Vol. 34 
