NRRA: Environmental Impacts on the Performance of Pavement Foundation LayersStatus: CompleteReport Date: 09/30/2021 Summary: Seasonal freeze-thaw weakening has a significant effect on pavement foundation performance. The seasonal freeze-thaw cycles cause extensive damage to the pavement from frost-related problems such as frost heave, frost boils, thaw weakening, total rutting, and degradation of mechanical properties. Changes in temperature of pavement foundation geomaterials during freeze-thaw cycles can significantly influence the performance of pavement foundation layers. It is crucial to monitor the changes in water content, temperature, and matric suction of aggregate base and subgrade soils to be able to predict the frost depth, freezing and thawing times, and number of freeze-thaw cycles. This project has two main goals: (1) develop a data-driven model to predict the maximum/minimum frozen soil depths and (2) freezing and thawing duration and numbers via use of standard climate data that includes precipitation, shortwave radiation, and air temperature. During this research, a model was developed and validated using the climate and environmental data collected from MnDOT. As a result of this research an Excel tool was developed that can predict frost depth, soil temperature, number of freeze-thaw cycles, and duration of freezing and thawing periods at a given soil depth via use of weather data. The required climate data include air temperature, relative humidity, wind speed, precipitation, and solar radiation. Final Deliverables: NRRA: Environmental Impacts on the Performance of Pavement Foundation Layers (Report #NRRA202108) Related Materials: Related Research: