Experimental Study of Model Cable Inter-supported by a Shape Memory Alloy Wire

Abstract

<p>This study proposed and tested a system of a stay cable transversely attached with a tensioned Shape Memory Alloy (SMA) wire. Cyclic tension loading test of pre-tensioned 0.5mm diameter SMA wire was firstly conducted. The effective modulus and energy dissipation per unit volume were derived from the tested hysteretic loops of pre-tensioned SMA wire. The pre-strain effects on the effective modulus and energy dissipation of SMA wire was discussed based on the test results. Then vibration mitigation experiment of a model stay cable transversely attached with a tensioned SMA wire was conducted. The strain level of SMA wire was calculated from the stay cable force increment. Both the 1st and the 2nd in-plane vibration mode were tested in the experiment. The effects of the SMA wire installation location and pre-strain on frequency and damping ratio of the model-cable-SMA-wire system were discussed. The test results confirmed there was an optimal pre-strain of SMA wire for the maximum mode damping larger than 0.50%. The study confirmed great potential application of pre-strained SMA wire as cross-ties for stay cable vibration mitigation.</p>