Developing Optimized Concrete Pavement Designs Using the DARWin-ME / Mechanistic Empirical Pavement Design Guide and Cost Analysis

Historically pavement designs have been based on an engineering analysis where the pavement thickness and features are chosen to meet the traffic, environmental, and subgrade conditions for the project. For concrete pavements, this means that the pavement is typically designed to last the entire design period (e.g., 20 to 40 years) without intermittent rehabilitation activities. Asphalt pavements, however, are designed with planned periodic future rehabilitation activities in mind. This often results in concrete pavements being overdesigned with high initial costs, but lower rehabilitation costs. Conversely asphalt pavements have lower initial costs, but higher rehabilitation costs. Though life cycle cost can influence the pavement type selection, more often the final pavement selection is based on initial costs. This paper presents a model to optimize concrete pavement designs by balancing the initial costs of the pavement, which is primarily affected by the thickness and specific design features used, and the rehabilitation costs of the pavement based on the pavement's predicted performance using the recently adopted American Association of Highway and Transportation Officials (AASHTO) Mechanistic Empirical Pavement Design Guide (MEPDG) and its companion software, DARWin-ME.