Opus caementicium uncovered inside a characteristic Roman arch. In contrast to modern-day concrete buildings, the concrete used in Roman structures was usually coated with brick or stone. The Romans applied concrete thoroughly from three hundred BC to AD 476.[18] Through the Roman Empire, Roman concrete (or opus caementicium) was constructed https://garretta4lk6.laowaiblog.com/34722917/fascination-about-concrete-reinforced-steel