THE FAST TRACK REVOLUTION

Fast Track concrete paving has evolved in many ways since the revolution started in 1986. It began as a bonded overlay project and then was used in Iowa for early opening on new construction, early opening on an unbonded overlay, early opening of only a portion of a project, expediting airport runway paving, overnight reconstruction of intersections, and reconstruction under traffic. A number of aspects make Fast Track unique from conventional concrete paving. Concrete mixtures may contain Type III cement for opening in less than a day or Type I or Type II for opening at ages greater than one day. The cement content of the mixture, with any of the cement types, is used to affect opening time. The curing method can be conventional curing compounds. Or, for very early opening, insulating blankets may be used. The minimum strength for opening to traffic must be determined by each agency. A different value may be set for different Fast Track applications. Fast Track presents a significant problem for the joint sealing operations. The wet condition of the joint face at the time of opening runs counter to normal joint sealing conditions. Various combinations of type of cement, cement content, and blanket or standard cure, offer a continuum of Fast Track schemes to meet almost any open requirement. These aspects must be considered and the right combination used to accomplish the requirements of each specific project. After ten years, Fast Track has changed. It has broadened to where it can meet almost any early open requirement. The revolution continues. (a) For the covering entry of this conference, please see IRRD abstract no. 878228.