Selection of Preoverlay Repair Methods for Asphalt Overlay on Asphaltic and Composite Pavements in Wisconsin Based on Cost Effectiveness

Abstract

Asphalt concrete (AC) overlay is a commonly used rehabilitation technology for existing distressed pavements. Current practice regarding the selection of preoverlay repair is based on the experience of designers and field engineers. Therefore, the performance of asphalt overlays vary significantly. There is a need to develop a guideline to select the most cost-effective preoverlay repair methods. In this study, a database that includes 338 historic asphalt overlay projects is developed. The service lives of the asphalt overlays, based on each preoverlay repair method, are determined. The agency and user costs over the service lives are analyzed. The results indicate that the pavement distress index (PDI) development method based on the regression can be used to predict the service lives of overlays on AC and composite (COMP) pavements (concrete pavement that has been overlaid at least once). For existing AC pavements, milling is recommended when alligator cracking is extensive and no preoverlay repair is needed for other major preoverlay distresses. For existing COMP pavements, milling is recommended regardless of the preoverlay distresses’ extent and severity.