Optimizing Asphalt Mixture Designs for Low-Volume Roads of Minnesota

Status:  Complete
Report Date:  10/04/2023


Minnesota’s varied weather conditions take a toll on its rural roads, but improvements in asphalt design may offer better durability. A significant percentage of the state’s rural roads are deemed low volume, which means they see fewer than 400 vehicles in a day. Although these roads do not experience the issues associated with high traffic levels, they struggle with problems due to environmental conditions, especially freeze-thaw cycles common in cold weather states. The resulting cracks, ruts and potholes shorten the lifetime of the pavement and can cause safety issues for drivers. To address these road conditions, researchers analyzed asphalt mixtures to develop better construction options for rural asphalt roads. Asphalt pavements are designed to include air pockets, or voids, that allow for some water to flow through the asphalt structure, but water can also freeze in these pockets when the temperature drops. By controlling for the air pockets and other asphalt properties in rural settings, researchers identified an asphalt mixture that promises greater durability for low-volume roads.

Final Deliverables:

Related Materials:

Related Research: