Numerical and experimental investigation on cable vibration mitigation using shape memory alloy damper

This paper estimates the effectiveness of shape memory alloy (SMA) damper on cable vibration mitigation by numerical simulation and experimental investigation. First, a simplified constitutive law of superelastic SMA and the structure of the SMA damper developed by superelastic SMA wires are presented. Second, based on Hamilton principle and Galerkin method, the vibration equations for a cable-SMA damper system are established, and numerical solutions of which are adopted to obtain the dynamic responses of the system without and with SMA damper using the Newmark-beta method. Finally, numerical simulation associated with a practical cable and experiments on a scaled test cable are, respectively, carried out to investigate the effectiveness of SMA damper on the vibration mitigation of the cable subjected to the free and forced vibration. Numerical simulations indicate that the SMA damper developed can clearly shorten the free vibration decay time of the cable and increase the equivalent damping ratios of the cable with the reasonable parameter and location of SMA damper, and that it can decrease the displacement response amplitude when the cable is subjected to white-noise excitations. The experimental results show that the SMA damper can reduce the acceleration response of the test cable under free vibration and forced vibration induced by the deck motion. As a result, the SMA damper developed is very effective for mitigating cable vibration. Copyright (C) 2009 John Wiley & Sons, Ltd.