Seismic performance of the self-centering rocking columns with SMA L-shaped plates

Shape memory alloy (SMA) as a high-performance material with intelligent properties, has been recognized as a promising alternative solution for achieving self-centering of the structure. In this study, based on the excellent characteristics of SMA, SMA L-shaped plate was developed and applied to install on the rocking interface of the rocking column to enhance the seismic resilience, and the seismic performance of the self-centering rocking columns with SMA L-shaped plates was investigated through experiment and numerical simulation. To this end, the mechanical properties of SMA plate were firstly investigated experimentally. Then the quasi-static cyclic loading tests of the rocking column with SMA L-shaped plates were carried out, and its hysteresis behavior was investigated under different loading protocols with varying displacement amplitudes. For comparison, a rocking column with steel L-shaped plates was also tested. The experimental results showed that the rocking column with SMA L-shaped plates exhibited excellent flag-shape hysteresis behavior with satisfactory self-centering ability and stable energy dissipation capacity, and owned a large deformation capacity. Subsequently, the dynamic responses of the self-centering rocking column with SMA L-shaped plates were investigated by numerical simulation. It is found that compared to the steel L-shaped plates, the SMA L-shaped plates can effectively reduce the residual displacement responses of the rocking column and quickly restore to normal operation.