Yang Zhang, David J. White, Pavana K. R. Vennapusa, Alex E. Johnson, Maxim M. Prokudin
Dept. of Civil, Construction, and Environmental Engineering, Iowa State University
Base course (Pavements); Concrete pavements; Foundation engineering; Freeze thaw durability; Frost heaving; Geosynthetics; Geotextiles; Moisture content; Pavement layers
Frost heave of foundation materials causes severe joint deterioration in concrete pavements. Sufficient freezing depth, continuous water supply, and frost susceptible geomaterials are the three necessary factors leading to frost heave. To investigate the frost actions of deteriorated pavements with frost heaves at joint locations, the longitudinal pavement surface profiles were plotted by measuring vertical heaves crossing transverse joints. Specimens were cored to determine the moisture conditions at different layers. Ice lenses were found at layer interfaces, and frozen base layers with low permeability contributed to trapping water within joint spaces. Another objective of this study was to determine the local freeze-thaw conditions in pavements. Temperature sensors were installed during the reconstruction to estimate the frost penetration depths, lengths of freezing and thawing periods, and number of freeze-thaw cycles at different depths. Up to 1.1 m frost penetration depth was found, and it showed various lengths of freezing periods. The last objective was to evaluate the frost-heave and thaw-weakening susceptibility of the reconstructed foundation materials. Results indicated that all three geomaterials were medium frost-heave susceptible, and the soft subgrade showed high thaw-weakening susceptibility.