The invention of reinforced concrete in the 19th century revolutionized construction industry, architecture and urbanism.
Ernest L. Ransome was an English-born engineer and early innovator of the reinforced concrete techniques, discovered by François Coignet, who was
the first to use iron-reinforced concrete as a technique for constructing building structures. With the knowledge of reinforced concrete developed during the previous 50 years, Ransome innovated nearly all styles and techniques of the previous known inventors of reinforced concrete. Ransome’s key innovation was to twist the reinforcing steel bar improving bonding with the concrete.
image source: http://pcad.lib.washington.edu/person/2766/
reinforced concrete features
Reinforced Concrete is a composite material 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.
info source: https://en.wikipedia.org/wiki/Reinforced_concrete