'''Reinforced concrete''' ('''RC'''), also called '''ferroconcrete''', is a [[composite material]] in which [[concrete]]'s relatively low [[ultimate tensile strength|tensile strength]] and [[ductility]] are compensated for by the inclusion of reinforcement having higher tensile strength or ductility. The reinforcement is usually, though not necessarily, steel bars ([[rebar]]) and is usually embedded passively in the concrete before the concrete sets. However, [[Prestressed_concrete#Post-tensioned_concrete|post-tensioning]] is also employed as a technique to reinforce the concrete. In terms of volume used annually, it is one of the most common engineering materials.<ref>{{Cite web|date=2016-12-19|title=16 Materials Every Architect Needs to Know (And Where to Learn About Them)|url=https://www.archdaily.com/801545/16-materials-every-architect-needs-to-know-and-where-to-learn-about-them|access-date=2021-07-09|website=ArchDaily|language=en-US|archive-date=2021-07-09|archive-url=https://web.archive.org/web/20210709160757/https://www.archdaily.com/801545/16-materials-every-architect-needs-to-know-and-where-to-learn-about-them|url-status=live}}</ref><ref>{{Cite web|last=Sarah|date=2017-03-22|title=When should you use reinforced concrete?|url=https://ekaconcrete.com/use-reinforced-concrete/|access-date=2021-07-09|website=EKA Concrete {{!}} Direct Supplier of Ready Mix and Site Mix Concrete|language=en-GB}}</ref> In [[corrosion engineering]] terms, when designed correctly, the alkalinity of the concrete protects the steel rebar from [[corrosion]].<ref>{{Cite book|url=https://www.worldcat.org/oclc/20693897|title=Structural materials|page=360|date=1990|publisher=Materials Dept., Open University|others=George Weidmann, P. R. Lewis, Nick Reid, Open University. Materials Department|isbn=0-408-04658-9|location=Milton Keynes, U.K.|oclc=20693897}}</ref>
