Opus caementicium uncovered inside of a attribute Roman arch. In distinction to present day concrete constructions, the concrete used in Roman structures was usually lined with brick or stone. The Romans used concrete extensively from 300 BC to Advert 476.[18] During the Roman Empire, Roman concrete (or opus caementicium) was https://userbookmark.com/story19725691/an-unbiased-view-of-reinforced-concrete-meaning