Strengthening and prestressing of bridge decks with ribbed iron-based shape memory alloy bars

Given the increasing age of our built environment, including concrete structures, stakeholders in construction industry require innovative and effective strengthening methods. In several studies onsite applications, iron-based shape memory alloy (Fe-SMA) reinforcements have proven to be competitive alternatives well-established materials. The objective this investigation was study effectiveness two different prestressed methods for members flexure using recently available ribbed Fe-SMA (“memory-steel”) bars. Reinforced slabs similar cantilever extension box-girder cross-sections were strengthened only cementitious anchorages subjected quasi-static loading. first method comprised removal cover installation memory-steel bars with an additional mortar layer. second cutting grooves cover, followed by (near-surface-mounted). prestress obtained via resistive heating specimens exhibited highly improved cracking, yielding, maintained ductility until ultimate compression failure. Observations utilizing a digital image correlation system indicated damage-free prestressing process no premature failure reinforcement. Different analytical approaches used estimate prestress.