Asphalt rehabilitation projects using a 2-inch mill and overlay approach are now expected to last even longer. Research by the Colorado Department of Transportation (CDOT) indicates a life expectancy of 12 years for these projects. Ten years was previously considered the accepted life-cycle.
The study analyzed performance data from many projects and evaluated multiple rehabilitation strategies. As a result, CDOT enacted a policy change that increases the life expectancy of asphalt mill and mill overlays from 10 years to 12 years regarding life-cost analyses.