Inventor: Joseph Aspdin

Concrete by definition is made up of two parts, aggregate and cement mixed with water.  Aggregate can be a mixture of any rock like substance, sand and gravel.  The cement hardens when mixed with water in a process known as hydration and is able to bind the aggregate together.  Concrete has been in existence in primitive forms since 5600 BC.  One modern form of concrete known as hydraulic cement was created in 1756 by engineer John Smeaton and consisted of pebbles and powdered brick.  The concrete we use today, however, was invented in 1824 by Joseph Aspdin and was known as Portland cement.  It was made up of the first synthetic cement, consisting of ground up limestone and clay that were heated up in a kiln.  This formula was strong enough to be the primary recipe for concrete now, almost two centuries later.  Another step this type of concrete was the invention of reinforced concrete which combined the properties of steel and concrete.  Ferroconcrete as this is sometimes called coats steel or iron bars with concrete and is very sturdy and long lasting as a support. 

*Pictures from <http://www.dejobaan.com/textures/preview.htm>

SOURCES:

Bellis, Mary. “The History of Concrete and Cement”, 17 Jan 2004, <http://inventors.about.com/library/inventors/blconcrete.htm>

• This page gives a history of concrete from ancient times through the present with an emphasis on Portland Cement

Lambert, Paul.  “Cement and Concrete – History and Development”, 17 Jan 2004 <http://www.azom.com/details.asp?articleID=1317>

• This site provides a history of various forms of concrete since ancient times