Reinforced concrete, also called ferroconcrete, is a composite material in which concrete's relatively low 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, 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. In corrosion engineering terms, when designed correctly, the alkalinity of the concrete protects the steel rebar from corrosion.
A heavy, reinforced concrete column, seen before and after the concrete has been cast in place around its rebar frame
The novel shape of the Philips Pavilion built in Brussels for Expo 58 was achieved using reinforced concrete
Rebars of Sagrada Família's roof in construction (2009)
Christ the Redeemer statue in Rio de Janeiro, Brazil. It is made of reinforced concrete clad in a mosaic of thousands of triangular soapstone tiles.
A composite material is a material which is produced from two or more constituent materials. These constituent materials have notably dissimilar chemical or physical properties and are merged to create a material with properties unlike the individual elements. Within the finished structure, the individual elements remain separate and distinct, distinguishing composites from mixtures and solid solutions. Composite materials with more than one distinct layer are called composite laminates.
A black carbon fibre (used as a reinforcement component) compared to a human hair
Concrete is a mixture of adhesive and aggregate, giving a robust, strong material that is very widely used.
Plywood is used widely in construction
Composite sandwich structure panel used for testing at NASA