Development of unit cost estimating models with respect to scale economies and material price volatility for use in probabilistic life cycle cost analyses

Abstract

In regard to pavement materials, some state highway agencies are naturally inclined to favor one material over others based on familiarity with construction of the pavement and the typical distress and failure characteristics of the material. Both asphalt and portland cement concrete pavements have their own unique advantages and disadvantages, and their use by state highway agencies is contingent upon numerous factors including technical performance and engineering economy. Traditionally, one of the main factors in pavement material selection has been the analysis of initial construction costs. However, with more transportation assets added to the state's inventory each year and financial resources becoming more restricted, state highway agencies have recognized the need to choose the best pavement option for their citizens that will require minimum agency resources to maintain and rehabilitate requires more than an analysis of initial costs. This research seeks to analyze the life cycle costs of these two paving materials in the state of Alabama while investigating which projects warrant a life cycle cost analysis (LCCA). Design and construction practices of concrete pavements will also be examined so that factors that significantly influence the life cycle costs of this pavement material can be identified. This research will also examine the availability of engineering and economic data, determine what data is necessary to provide a practical estimate to the total cost of ownership for both pavement alternatives, and address such issues as forecasting initial construction costs for use in a stochastic LCCA and identifying significant issues with the current LCCA process.