Using a retrospective case study, the paper discusses the issues connected with selecting pavement types using a framework of life-cycle economic analysis. The study is based on Hwy 402, built by the Ontario Ministry of Transportation about 12 to 15 years ago. This 100 km-long 4-lane rural freeway in southwestern Ontario utilizes three different pavement types: a) full depth asphaltic concrete pavement utilizing two somewhat different designs, b) composite pavement, a structural Portland cement concrete slabl covered with a thin asphaltic concrete layer, with two different designs; and, c) asphaltic concrete pavement with a granular base. The performance of all pavement sections has been systematically monitored over the years and, about three years ago, weigh-in-motion scales were installed in both directions of the freeway. The available data were used to: a) contrast the observed performance of different pavement types, b) compare the observed and predicted pavement performance, and c) carry out cost-benefit evaluation of different pavement types. The results indicate that it is difficult to compare the performance of different pavement types because no universal scale exists to measure the performance, and difficulties met in quantifying the effect of traffic loads. Using Ride Comfort Rating only, a good agreement was obtained between the observed and predicted pavement performances. For the pavement structures investigated, the results of life cycle costing indicate a better outcome for full depth pavements. (A)
Abstract