Incorporating variability into life cycle cost analysis and pay factors for performance-based specifications

A model has been previously developed to indicate how overlay thickness, total prior cracking, annual freeze index, annual days with precipitation, and accumulated equivalent single axle loads (ESALs) after eight years affect pavement deterioration, in terms of roughness, for asphalt overlay pavements. This paper uses the specified model, as well as data from the Canadian Long Term Pavement Performance test sites, to determine the service life. This paper will examine how the variability associated with the overlay thickness, total prior cracking, and accumulated ESALs after eight years affect the service life. These results will then be used to calculate life cycle costs. Furthermore, the life cycle cost will account for the variability associated with the discount rate used in the life cycle cost analysis. Finally, a sensitivity analysis of the life cycle costs is conducted to determine how pay factors should be related to performance-based specifications for asphalt overlay pavements.