Opus caementicium exposed in a attribute Roman arch. In contrast to modern concrete constructions, the concrete Utilized in Roman buildings was normally covered with brick or stone. The Romans utilized concrete thoroughly from 300 BC to AD 476.[18] In the course of the Roman Empire, Roman concrete (or opus caementicium) https://bodyguard38260.arwebo.com/58254410/5-simple-statements-about-concrete-reinforced-stone-explained