ABSTRACT
Shape memory alloy (SMA) has shown great promise in retrofitting of aged infrastructure because it could be employed to conveniently apply prestress. However, the stress recovery behavior of iron-based SMA (Fe-SMA) has not been fully understood. This study presents an experimental study on Fe-SMA subjected to multi-activation. Eight specimens were prepared and loaded by two million cyclic loading simultaneously with thermal scenarios. Afterward, they were re-activated up to four times. Lost recovery stress due to fatigue was pronouncedly retrieved by reactivation. In addition, the Fe-SMA samples after fatigue loading could be reused to provide prestress for other applications but the count for reusability was limited. This study explores functional-fatigue behavior of the material and provides some useful suggestions for the strengthening technique.
