Vibration Mitigation of Stay Cable Using SMA Wire: A Numerical Study

Stay cables are load carrying members in cable-stayed bridges that experience vibrations due to wind, rain, and traffic-induced excitations and may have fatigue damage. To protect cable damages from fatigue issues, mechanical dampers are commonly used. This paper approaches the problem by conducting a numerical simulation of a steel cable specimen of diameter 10.4 mm and length 3.2 m. First, the dynamic behavior of the cable in free vibrations is investigated, followed by a forced vibration analysis of the cable. The SMA wire hysteresis behavior was also computed and the responses of cable without SMA wire were computed in terms of free and forced vibration. The SMA wire was used at different locations of cable and by using damping coefficient values. A wire of diameter 2 mm, made by shape memory alloy (SMA), is introduced to the cable. The variation of the amplitude response is investigated for a variety of excitation frequencies. The goal is to determine how the dynamic behavior of the steel cable changes when SMA wire is used and to determine which location of SMA at the taut cable may provide the best results in terms of large vibration mitigation of cable. It is found that the location at the cable where maximum amplitude dissipation occurs is the best location to attach the SMA wire.