2019 CSCE Annual Conference - Laval (Greater Montreal)

2019 CSCE Annual Conference - Laval (Greater Montreal) Conference


Title
Seismic Performance of Steel Braced Frames Reinforced with Shape Memory Alloy Wires

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Author(s)
Ms. Kezia Varughese, University of Calgary (Presenter)
Dr. Raafat El-Hacha, University of Calgary
Dr. Fadi Oudah, Dalhousie University
Abstract

Shape memory alloys (SMA) have just recently made their way into structural design, and through studies have proved to be quite effective in increasing a structures strength and performance. Earthquakes are one of the most chaotic natural disasters that occur around the world, significantly impacting infrastructure to the point where cities lose their ability to function as bridges and hospitals are destroyed. The main objective of this paper is to investigate the effectiveness and feasibility of active techniques for seismic retrofitting of structures using pseudoelastic (PE) NiTi SMA wires. Three steel braced frames were designed and constructed; one steel control frame and two SMA frames. A free vibrations test was conducted to determine the natural frequency and damping ratio of the two systems. It is proposed that with this experiment, the SMA frame will prove to be more flexible than the steel frame and thus have a slower natural frequency. By having a more flexible system, more energy can be dissipated during the excitation limiting the amount of damage done to the structure. The use of shape memory alloys proposed in this research not only controls where the damage occurs but limits it to be very insignificant, where no structural elements would need replacing. Findings of this research are expected to add valuable knowledge to the field of seismic retrofitting of structures and widen the potential applications of the SMA in the structural engineering field.