IJE TRANSACTIONS C: Aspects Vol. 33, No. 3, (March 2020) 410-418 Please cite this article as: H. Jahangir, M. Bagheri, Evaluation of Seismic Response of Concrete Structures Reinforced by Shape Memory Alloys, International Journal of Engineering (IJE), IJE TRANSACTIONS C: Aspects Vol. 33, No. 3, (March 2020) 410-418 International Journal of Engineering Journal Homepage: www.ije.ir Evaluation of Seismic Response of Concrete Structures Reinforced by Shape Memory Alloys H. Jahangir a , M. Bagheri* b a Department of Civil Engineering, Ferdowsi University of Mashhad, Mashhad, Iran b Department of Civil Engineering, Birjand University of Technology, Birjand, Iran PAPER INFO Paper history: Received 30 November 2019 Received in revised form 22 December 2019 Accepted 17 Januray 2020 Keywords: Maintenance Costs Plastic Hinge Length Reinforced Concrete Structures Shape Memory Alloys Time History Analysis A B S T RA C T Shape memory alloys (SMAs) are unique smart materials that have many advantages, such as ability to resist large strains without leaving residual strains and ability to recover original form. However, the high costs of SMAs have limited their usage. This paper evaluates the behavior of concrete structures equipped with SMAs in an optimal manner as they are being used along with plastic hinge of the beams. For this purpose, a reinforced concrete (RC) beam, a 2D RC frame and a 3D RC building were considered, which were tested in previous studies under cyclic loading and on a shaking table. After verifying RC beam in the Seismostruct software, the steel rebars are replaced by SMAs in all connections of models and time history analysis is performed. The seismic response of concrete structures equipped with SMAs is compared with the conventional RC structures. The maximum base shear and roof displacement, amount of residual displacement and distribution of interstory drift at the structure height are among the factors to be evaluated. The results showed that, due to the use of SMAs in concrete structures, the maximum base shear did not significantly change compared with the conventional RC structures, and the residual displacements in the structure roof have been reduced. On the other hand, the maximum displacement of the roof was increased in the structures with SMAs. The concrete structures equipped with SMAs experience a slight residual deformation, and the distribution of interstory drift is even more uniform at the height of such structures. doi: 10.5829/ije.2020.33.03c.05 1. INTRODUCTION 1 Structures in the areas with high seismic hazard are severely damaged by strong earthquakes. In the reinforced concrete (RC) structures, the damages mostly occur in the plastic hinge of the beams and cause residual displacements in the structure [1]. Although, the RC buildings may resist strong earthquakes, the resulting residual displacements increase the repair and reconstruction costs and greatly reduce the resistant of structures to the aftershocks [2]. To solve this problem, methods such as the reinforcement of structural elements using the fiber reinforced polymer (FRP) [3,4] and fiber reinforced inorganic matrix (FRIM) composites can be utilized [5–7]. But, using the shape memory alloys with the self-centering feature can be a more appropriate solution. *Corresponding Author Email: mnsrbagheri@birjandut.ac.ir (M. Bagheri) Shape memory alloys (SMAs) are new smart materials that can resist large nonlinear deformations and return back to the original geometry after unloading which made them an appropriate choice for reducing the maintenance costs [8]. In the past decades, many researchers have evaluated the possibility of using SMAs for the structural applications such as dampers [9–11], reinforcements [12–17], bracing [18,19], seismic isolation systems [20–22] and actuators [23,24]. Although previous studies have shown that the use of SMAs can reduce the residual displacements in the RC structures [25–27], their operating costs is one of challenges for using the alloys in the RC structures. One of the strategies to reduce the cost of these alloys is to use them only in the sections that experience more deformation due to the applied loads. The plastic hinges of beams are one of the sections evaluated in this paper. TECHNICAL NOTE