Early History
Manufacture of cement has a history, which traces back to millennia. Civilization first started to build mixing various minerals such as limestone, clay and chalk which when mixed with water, hydrate and rapidly become hard.
Throughout history, cementing materials have played a vital role and we have experimented all its applications that are nowadays used to build everything around us, houses, bridges, roads, hospitals, etc.
The oldest known surviving concrete is to be found covering the floor of an old house in Lepenski Vir, in the former Yugoslavia and was thought to have been laid in 5,600 BC using red lime as the cement.
The Chilean Indians used hydraulic conglomerate using burnt alga to cover the walls of their huts. The Egyptians advanced to the discovery of lime and gypsum mortar as a binding agent for building such structures as the Pyramid of Giza (2500 B.C) and in Troy and Micenas stone-walls were fixed together with clay.
The Romans who were prolific builders used burnt calcareous (calcium bearing) rocks along with pozzolanic (volcanic ash) materials in an era Before Christ. They used this material to build important civil buildings, drains, and water works and as conglomerate providing strength and weight to structures.
The structures built by them, like the Pantheon is one of the main examples of the use of this material. The Pantheon was built by Agrippa in the year 27 B.C. After a devastating fire it was reconstructed by Hadrian in the year 120 A.D. The building is circular with a concrete dome of 44 meters high with a central opening (oculus). The Pantheon holds the record for the largest unreinforced concrete dome and was built with hydrate of lime, pozzolanic ash and lightweight pumice. The cementitious material was laid in three layers that became less thick as approaching the oculus.
This same cementitious material was used to build the walls of Pompeii’s amphitheatre (75 A.D.) and the foundations and internal walls of the Coliseum (80 A.D.).
The Romans made many developments to supply their cities with running water and although they were not the first to do so, their water system is considered one of the most complex and influential. The first channels were made of stone, later concrete and combinations of bricks with rubble were used bringing great improvements to their population.
After the Roman Empire this art was lost and it was not until the XVIII century that the use of cement was recovered.
