Self-centering of shape memory alloy fiber reinforced cement mortar members subjected to strong cyclic loading

• Published in: Materials and structures Vol. 46; no. 4; pp. 651 - 661
• Main Authors: Shajil, N., Srinivasan, S. M., Santhanam, M.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.04.2013; Springer; Springer Nature B.V
• Subjects: Applied sciences; Building construction; Building Materials; Buildings. Public works; Civil Engineering; Concretes. Mortars. Grouts; Cyclic loads; Deformation; Ductility; Engineering; Exact sciences and technology; Fatigue (materials); Fiber reinforced cements; Fibre reinforced concrete (including asbestos cement); Machines; Manufacturing; Materials; Materials Science; Mortars; Original Article; Processes; Reinforcement; Shape memory alloys; Solid Mechanics; Strength of materials (elasticity, plasticity, buckling, etc.); Structural analysis. Stresses; Theoretical and Applied Mechanics; Self-centering; Pullout test; Superelastic effect; SMA reinforced concrete; 3-Point bending; Fiber reinforced mortar; Ductility; Stress strain relation; Construction materials; Elasticity; Centering; Experimental study; Shape memory alloy; Austenite; Cyclic load
• ISSN: 1359-5997; 1871-6873
• DOI: 10.1617/s11527-012-9923-1

In addition to ductility of the reinforced concrete, it is desirable to have large recoverable deformations (self-centering ability) under strong cyclic loading conditions. Since steel reinforcement cannot regain its shape beyond yielding, the performance deteriorates enormously when subjected to a strong cyclic load. An alternative reinforcement material such as shape memory alloy (SMA) could offer scope for self-centering, thus improving performance especially after a severe loading has occurred. In this study, the load-deformation characteristics of SMA fiber reinforced cement mortar beams under cyclic loading were investigated to assess the self-centering mechanism. The study involves experiments on a beam structure and related analysis for the prediction of self-centering. Apart from the energy dissipation through its ductility, it is shown in this study that shape memory alloy reinforced cement mortar has very good self-centering properties that may be crucial in bringing back the functionality of a structure and prevention of permanent secondary deformations that may lead to catastrophic failure in some structures.