Shape-memory NiTi alloy rebars in flexural-controlled large-scale reinforced concrete walls: Experimental investigation on self-centring and damage limitation

• Published in: Engineering structures 2020-10, Vol.220, p.110865, Article 110865
• Main Authors: Almeida, João Pacheco de, Steinmetz, Martin, Rigot, Fabrice, de Cock, Sébastien
• Format: Article
• Language: English
• Subjects: Earthquake damage; Earthquakes; Energy dissipation; Experimental tests; Flexing; Nickel base alloys; Reinforced concrete; Reinforced concrete wall; Reinforcing steels; Repair; Residual displacements; Seismic activity; Self-centring systems; Shape memory alloys; Superelasticity; Walls
• ISSN: 0141-0296; 1873-7323
• DOI: 10.1016/j.engstruct.2020.110865

•Two large-scale cyclic quasi-static tests on reinforced concrete walls are described.•Steel is replaced by shape memory alloy rebars in one wall boundary elements’ base.•Wall with SMA shows large displacement ductility and plump energy-dissipation cycles.•Residual drifts for the RC wall with SMA are drastically reduced (ratio of 1/3).•Major improvements in terms of vertical residual elongation are also achieved. Economic damage and repair costs due to earthquakes are largely connected with permanent residual structural displacements. This study develops and tests the use of shape-memory Niti alloy rebars as a replacement to steel rebars in reinforced concrete walls. Large-scale cyclic quasi-static experimental tests on two units, predominantly behaving in flexure, show a clear reduction of residual displacements and damage. Additionally, the superelastic flag-shaped hysteretic response of the smart alloy in the wall boundary elements guarantees a sizeable energy dissipation, opening a promising avenue both for new construction and repair works. The experimental data is openly available (DOI: 10.14428/DVN/2QBQVJ).