OPTIMALITY OF HIGHWAY PAVEMENT STRATEGIES IN CANADA

The flexible pavement performance predictions of a deterioration model proposed by Small, Winston, and Evans are compared with those estimated from a deterioration model developed for Ontario conditions. The proposed model by Small et al., incorporating even a very modest rate of annual environmentally induced degradation, severely underestimates the initial service lives of Ontario pavements. The life-cycle cost characteristics of Ontario pavements are illustrated, and it is concluded that the optimal pavement strategy is insensitive to changes in the initial pavement thickness. This conclusion is in contrast to the "underbuilt" conclusions by Small et al. Typical average and marginal cost functions that must form the basis of any rational axle weight-based road user charge system are also presented.