Roman concrete called opus caementicium in Latin was used from the late Roman Republic until the end of the Roman Empire. It was used to build monuments, large buildings and infrastructure such as roads and bridges. The quality of the concrete was excellent and the buildings and monuments still standing today are a testament to the strength of their construction!
Concrete was usually covered as concrete walls were considered unaesthetic. Roman builders covered building walls with stones or small square tuff blocks that would often form beautiful patterns noting that brick faced concrete buildings were common in Rome especially after the great fire of 64 AD.
Roman concrete or opus caementicium was invented in the late 3rd century BC when builders added a volcanic dust called pozzolanato mortar made of a mixture of lime or gypsum, brick or rock pieces and water. Concrete was made by mixing with water: 1) an aggregate which included pieces or rock, ceramic tile, pieces of brick from previously demolished constructions, 2) volcanic dust (called pozzolana) and 3) gypsum or lime. Usually the mix was a ratio of 1 part of lime for 3 parts of volcanic ash. Pozzolana contained both silica and alumina and created a chemical reaction which strengthened the cohesiveness of the mortar.
Presented by Romano Pisciotti
IVECO Nigeria MPI info: email@example.com