Improving seismic performance of reinforced concrete structures by using ferrous based shape memory alloys

Abstract

Improving design of new buildings and retrofitting existing build, to resist the action of earthquakes, constitute an issue of primary importance. Among the emerging techniques that can be used for this purpose, reinforcing with ferrous based shape memory alloys has given promising results. These materials are cost-effective; they have excellent recentering capabilities, high damping properties and elevated resistance to corrosion. The potential of using these reinforcements when placed at the extremities of structural members of the building was investigated in this work. A comparative study was performed between this variant and the reference case where conventional steel rebars are employed. This was conducted in the case of a simple reinforced concrete frame having a symmetric configuration. The comparison has targeted moderate and strong seismic excitation. The studied structure was modeled by using SeismoStruct software to perform both pushover analysis and full nonlinear time history analysis. The obtained results have indicated that the use of shape memory alloys yields lesser demand in terms of base shear and support moment, while reducing residual deformations thanks to the recentering property of these materials.