PORTLAND CEMENT CONCRETE PAVEMENT OVERLAY OVER A BITUMINOUS PAVEMENT.

The initial stage construction completed in 1970 on Interstate 70 in western Kansas consisted of a 10-in. asphaltic concrete pavement. At the time of the second stage, 10 years later, the pavement exhibited signs of load and nonload associated cracking. A 3-in. second stage overlay had been planned during the initial design. Based on current conditions, traffic, and distress, a structural design called for a 5-in. asphaltic concrete overlay, Overlays generally do not control reflective cracking for appreciable periods of time. Therefore, additional rehabilitation strategies were proposed. Based on life cycle costs, a Value Engineering Committee selected an 8-in. portland cement concrete pavement to be placed over the existing asphaltic concrete base. That 10-mi overlay was constructed in 1983 and an additional 17 mi were let to contract in 1984.