The arizona department of transportation (adot) was one of the first state highway agencies to develop a formal pavement management system. Adot has been collecting pavement performance data since 1972. These data were used during a recent project for the development of a new flexible pavement overlay design procedure. In addition to conventional overlays, the design method permits the evaluation of milling and replacing the surface with either recycled or virgin mix.Two forms of models are needed, one for predicting the roughness after the treatment and one for predicting the rate of development of roughness over the life of the treatment. Several hypotheses of the factors affecting these models were developed on the basis of engineering judgment and pavement performance theories. However, from a statistical analysis of the data, the only factors found to affect theroughness after the overlay were the roughness of the pavement before the overlay and whether an asphalt concrete friction course was placed during the overlay construction. The rate of development of roughness was not affected by any of the design variables. This paper appears in transportation research record no. 1272, Pavement management and rehabilitation 1990.
Abstract