Concretum at the AAAE airport planning design and construction symposium in Denver, Colorado. The United States of America have a great number of airports, which need to be well maintained in order to assure safety at all times. Shutting down parts of the airfield is not an option, but overnight replacement of airfield surfaces is an efficient solution to minimize traffic interruption. Concretum’s rapid-hardening concrete makes this possible! The airports and their operators show great interest.