Behavior of SMA reinforced concrete beam

The concrete beams reinforced with shape memory alloy (SMA) strands were made in this study. Single-point on mid-span loading tests were conducted on the beams reinforced with SMA strands and the ordinary reinforced concrete beams with the same dimension and the same reinforcement ratio to compare their mechanical properties, such as bearing capability, residual deflection and residual crack width. The influence of prestress of SMA strands and bonding status between SMA strands and concrete were also analyzed. The results indicate that SMA strands can reduce the residual deflection, the residual crack width and consequently increase the self-rehabilitation of the concrete beams. Besides, the bearing capacity of the beams reinforced with SMA strands increases more greatly than that of the ordinary concrete beams, and the bonding status has much influence on the bearing capability of the beams. Moreover, for the unbounded SMA reinforced concrete beam, prestress could increase the bearing capability and the damping capability of the beams.