Freeze-thaw damage presents a critical and persistent challenge to roadways in cold regions. This damage is driven by the expansion of pore water during freezing, causing frost heave, followed by structural weakening and settlement during thawing. Seasonally frozen regions, encompassing approximately 55% of exposed land in the Northern Hemisphere and 37% of the earth’s landmass, are particularly susceptible to these effects. Regions in the northern United States, Canada, northern Europe, and northern Asia experience elevated maintenance demands and repair costs due to freeze-thaw effects. The United States incurred $27.46 billion in road maintenance costs in 2019 alone, and freeze-thaw degradation is considered a major contributing factor to these expenses. Consequently, there is an imperative need for resilient roadway designs to effectively mitigate freeze-thaw effects, reduce maintenance costs, and extend service life. This dissertation investigates strategies to enhance freeze-thaw resilience in roadways through innovative water-repellent treatments and improved drainage using woven wicking geotextiles. It also explores methods for characterizing frost heave-thaw settlement in the field and highlights the importance of a uniform pavement foundation for long-term performance. Migrated water from the vadose zone is the primary contributor to frost heave. Water repellents can limit this influx by making the soil hydrophobic, thus reducing the freeze-thaw damage. The effectiveness of water-repellent treatments was evaluated through frost heave-thaw weakening tests in the laboratory. Silane, a water-repellent additive, was applied by spraying at varying concentrations to frost-susceptible soils from Iowa. The silane treatment resulted in a frost heave reduction of 57% to 80%. It was found that increasing the number of silane-treated layers was more effective than increasing the concentration, highlighting the importance of layered applications for optimal performance. Subsequent field study focused on the application of water-repellent treatments in granular roadways. Four Field test sections were constructed, including one control and three treated sections with two different water repellents and application methods, to evaluate the effectiveness of these treatments in mitigating freeze-thaw damage. Soil moisture content, frost heave-thaw settlement, temperature, and weather data were collected from the field test sections using sensors, and field performance tests were conducted seasonally. The treated sections demonstrated improved resistance to frost heave and reduced moisture accumulation during thaw periods. Additionally, the control section exhibited a significant stiffness reduction of 68% after winter, while treated sections showed lower reductions of 35%, 48%, and 53%, respectively. The role of woven wicking geotextiles in enhancing freeze-thaw resilience was investigated through both large-scale laboratory tests and field test sections. These geotextiles were installed at the subgrade-subbase interface to facilitate improved moisture drainage. Laboratory results showed a significant improvement in drainage efficiency and stiffness for the reinforced section with woven wicking geotextile compared to the control section. For field evaluation, one control and one reinforced section were constructed on Interstate I-94 at the Minnesota Road Research Facility (MnROAD) in a wet-freeze climate. Results demonstrated that the reinforced section maintained stable volumetric moisture content (VMC) in the subgrade and subbase layers, with reduced moisture accumulation during thawing and precipitation. Advanced monitoring techniques, including Shape Array (SAA) sensors and LiDAR, were evaluated to characterize frost heave and thaw settlement in the field. The displacement profiles from SAA were in good agreement with temperature, moisture, and matric potential measurements, validating the reliability of the SAA data. Accurate measurement of these displacements is essential for transportation agencies to make informed decisions on spring load restrictions and maintenance planning, ensuring roadway stability and safety. Lastly, the influence of initial stiffness and foundation uniformity on long-term pavement performance was analyzed for six test sections at MnROAD. Probabilistic analysis, complemented by semivariograms and distress mapping, demonstrated a correlation between foundation uniformity and long-term pavement performance. The regions with increased nonuniformity exhibited localized cracking and accelerated deterioration due to stress concentrations and differential movement during freeze-thaw.
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