Review of applications of shape memory alloys in civil structures

Shape memory alloy (SMA) is a novel functional material and has found increasing applications in a variety of areas. Recently, research efforts have been extended to using SMA-based devices for smart civil structures. This paper presents a review of application of the SMA materials for both passive and active vibration controls of civil structures. First, an overview of the characteristics of SMA is presented. The shape memory effect (SME) and pseudoelasticity, two major properties of SMA associated with the thermal-induced or stress-induced reversible hysteretic phase transformation between austenite and martensite, are reviewed. Those unique properties enable SMA to be used as actuators, passive energy dissipaters and dampers for vibration control of civil structures. This paper then reviews current researches using SMA-based devices or members for vibration control of civil structures with representative examples. For passive vibration control, the pseudoelastic SMA is used to increase the structural damping and dissipate energy. In the literature, the structure isolation and energy dissipation systems with the SMA material are two main systems for passive vibration control purpose. The operation mechanism, design and experimental results of several developed vibration control systems with passive or active SMA-based devices am presented in the paper. This paper concludes with a comparison of SMA-based damping devices with others and future trend of SMA applications in civil structures.