Seismic Performance of SMA/ECC Concrete Shear Wall with Self-Centering and Self-Repairing

This paper presents a complementary and synergistic material system that integrates superelastic shape memory alloy (SMA) with damage-tolerant engineered cementitious composites (ECC) to address the issues of yielding of steel bar and fragility of concrete. Reverse cyclic loading tests were done on four specimens to demonstrate the feasibility of this method, which consisted of conventional steel reinforced concrete shear wall (SW-R-C), steel reinforced ECC wall (SW-R-ECC), SMA reinforced concrete wall (SW-SMA-C), and SMA reinforced ECC wall (SW-SMA-ECC). The results showed that SW-SMA-C specimen exhibited remarkable self-centering capability, which can reach more than 85% even after large deformation compared to SW-R-C. Furthermore, superior reduced damage and better ductility were observed in the SW-SMA-ECC specimen, besides reduced residual displacement. The proposed approach indicated that it is more effective for SMA combined with ECC in improving the seismic performance of shear walls.