Factors Affecting the Performance of Pavement Preservation Treatments

Pavement preservation has become a very important tool box for agencies to maintain their roadway system. Federal Highway Administration (FHWA) funded the project titled "Factors Affecting the Performance of Pavement Preservation Treatments." The objective of this project was to determine how the uncertainty in the output of a model (such as the performance of a preservation treatment or the costs) can be apportioned to the different sources of uncertainty in the inputs (such as pavement condition, construction quality, quality of materials, traffic, and climate). The project evaluated the use of existing databases to determine the sensitivity of the factors on the performance of pavement preservation treatments. Unfortunately, these databases were determined not to be robust enough to answer the questions posed. An alternate approach was used by surveying experts in the field of pavement preservation treatments. This latter approach proved more successful. The impacts on the effect on performance were evaluated using sensitivity analysis and a life cycle cost (LCC) approach. The major factors that control the performance of many pavement preservation treatments that were considered in this study were: Pretreatment Pavement Condition, Materials Selection and Quality, Construction and Workmanship, Mix and Structural Design, Traffic Level, and Climate during and immediately after Construction. This paper focuses on the results of the sensitivity analysis and life cycle cost analysis which show that the variation from good conditions can have a dramatic effect on the life of the pavement preservation treatments as well as the associated costs to the agencies.