Development of a novel shape memory alloy-based self-centering precast segmental concrete column

Abstract

This study proposes a novel shape memory alloy (SMA)-based self-centering (SC) precast segmental concrete column (PSCC). The entire structural system, called SSC-PSCC, can be constructed via off-site precasting followed by on-site assembly. By using connecting SMA bolts and steel angles, wherein SMA and steel elements contribute to SC and energy dissipation (ED) capacities, respectively, SSC-PSCC is free from post-tensioned anchorages and wet joints, and the construction or repair process is considerably simplified. The behavior of SSC-PSCC was systematically studied through refined finite element models (FEMs) that were verified by good agreements with previous testing results. Cyclic behavior was simulated, and SSC-PSCC exhibits desirable SC and ED capacities. Compared with traditional post-tensioning (PT)-based SC-PSCC, SSC-PSCC has numerous advantages, including easy construction, quick repair and replacement of ED elements after earthquakes, and free from buckling of ED bars observed in traditional PT-based segmental columns. Furthermore, parametric studies were conducted to identify several crucial design parameters, such as prestrain in SMA bolts, axial load ratio, and segment reinforcement diameter. Design recommendations are provided on the basis of the results of the parametric studies.