NiTi super elastic shape memory alloy reinforcement for beam-column and column-foundation connection joints

Shape Memory Alloys (SMAs) using in civil engineering is one of the favorable research issues in recent decade. Many researchers have carried out intensive activities to utilize innovative devices and smart materials. Among the smart materials, SMAs due to physical and mechanical features are an eligible candidate for use in structural engineering applications. SMAs positive contribution to energy dissipation, self-adaptation, re-centering, and healing of the seismic behavior of structures have been emphasized by several researchers. Herein utilizing the SMAs as rebars in concrete buildings due to the mentioned remarkable characteristics is a favored research case. In this article, the seismic behavior of three height-type RC buildings using SMA reinforcement is investigated. For this purpose, SMA reinforcements as longitudinal bars utilize in structures with different stories (4, 6, and 8) which can be categorized as low, mid, and high-rise buildings. For each building SMA bar is used in four reinforcement arrangements; the case of full steel, the case of SMA at the beam-column connection region and steel bar at other regions, the case of SMA at column-foundation connection region and steel bar at other regions, and the of SMA at beam-column and column-foundation connection regions and steel bar at other regions. Nonlinear dynamic time history analysis method was performed to investigate the maximum story displacement, inter-story drift, base shear demand, residual displacement demand, nonlinear displacement at roof level, and chord rotation of beams for each building. The obtained results show the application of SMA bars with increasing of the stories is more significant.