Mechanistic-Empirical Pavement Design for Low-Volume Roads Impacted by Freeze-Thaw

Low-volume roads (LVRs) make up more than half the centerline mileage in the United States and most of these roads are not designed. Instead, a standard thickness is used for all roads or a rough catalog is used to determine the thickness of the pavement layers. The Cornell University Local Roads Program worked with local highway agencies in New York State to develop a mechanistic-empirical (ME) pavement design tool that overcomes the limitations of expertise and time of most LVR highway officials but takes advantage of their knowledge of the LVRs within their jurisdictions. The goal was to use existing information and apply it to the limited design related to LVRs. The tool developed, RoadPE: LHI, uses two common pavement-fatigue criteria-surface tensile strain and subgrade vertical strain-with simplified inputs and built-in trend analysis to determine the thickness of the asphalt layers for overlaid, mill and filled, rehabilitated, and reconstructed LVRs. An ME-based tool will allow highway managers to prepare better designs that account for real-world variations.