Cost Effective Base Type And Thickness For Long Life Concrete Pavements PDF Download

Pavement base layer quality is vital for long term performance. Low stiffness and shear strength can result in loss of support and increased tensile stresses under loads. To maintain uniform support under concrete pavements and ensure satisfactory performance, a stable, non-erodible, drainable base layer is necessary. The primary objective of this report is to quantify the aggregate base properties required for concrete pavement foundations in accordance with currently established layer thickness requirements. The effects of properties of different base layers on concrete pavement performance were evaluated, based on an the mechanical and hydraulic properties of typical base materials collected from previous MnDOT studies and relevant literature. Field measured environmental data from the MnROAD test facility was collected and used for calibration purposes. The effects of environmental conditions on long-term concrete pavement performance were evaluated accordingly. Data from the LTPP SPS-2 study and MnROAD test cells were analyzed to evaluate the effects of design and site factors on performance. Improved aggregate classes were established, considering gradation, aggregate shape properties and drainage characteristics. Field test data were analyzed to assess the effectiveness of open-graded aggregate bases in providing structural stability. The analytical gradation analysis and the discrete element modeling approach for engineering aggregate shape and gradation were used to predict field performance. The findings from the study were synthesized to recommend revisions for performance-related specifications for aggregate bases supporting concrete pavements. The results would ideally help design cost effective base types and thicknesses suitable for both concrete and asphalt pavements.