formwork

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formwork

construction

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Related Topics:: mold

formwork, Mold used to form concrete into structural shapes (beams, columns, slabs, shells) for building. Formwork can be of timber, steel, plastic, or fiberglass. The inside surface is coated with a bond breaker (plastic or oil) to keep the concrete from sticking to the mold. Important for high-rise construction is slipforming, whereby a vertical concrete element is continuously cast using a short section of formwork that is repeatedly disassembled and moved upward as each section is finished or that moves slowly and continuously as concrete is being placed. This is sometimes called a climbing form.

This article was most recently revised and updated by Kathleen Kuiper.

reinforced concrete

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reinforced concrete

building material

Also known as: ferroconcrete

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Last Updated: Mar 7, 2025 • Article History

Key People:: Pier Luigi Nervi; Auguste Perret; Albert Kahn; Jean Perronet; Felix Candela

Related Topics:: concrete; prestressed concrete; pretensioning; ferrocemento; posttensioning

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reinforced concrete, concrete in which steel is embedded in such a manner that the two materials act together in resisting forces. The reinforcing steel—rods, bars, or mesh—absorbs the tensile, shear, and sometimes the compressive stresses in a concrete structure. Plain concrete does not easily withstand tensile and shear stresses caused by wind, earthquakes, vibrations, and other forces and is therefore unsuitable in most structural applications. In reinforced concrete, the tensile strength of steel and the compressive strength of concrete work together to allow the member to sustain these stresses over considerable spans. The invention of reinforced concrete in the 19th century revolutionized the construction industry, and concrete became one of the world’s most common building materials.

The Editors of Encyclopaedia Britannica This article was most recently revised and updated by Adam Augustyn.