Date of Award
Master of Engineering (ME)
Bradley J. Putman, Committee Chair
Prasad Rao Rangaraju
Although the Mechanistic-Empirical Pavement Design Guide (MEPDG) was released in 2008 on behalf of the American Association of State Highway and Transportation Officials (AASHTO) by the National Cooperative Highway Research Program (NCHRP), many states still employ some version of a previous AASHTO Pavement Design Guide due to the amount of calibration required for local influences including climate, traffic loading, and material property variability. This study was conducted using dynamic modulus data from both laboratory-prepared and field-produced mixes. A sensitivity analysis utilized the laboratory data to analyze the effect of variations of subgrade strength and asphalt dynamic modulus on the critical pavement responses: vertical deflection, vertical stress, and horizontal tensile strain. The results of this analysis determined that the bottom layer of asphalt causes the largest variation in critical pavement responses. Statistical analyses were conducted to investigate the following scenarios: differences in mix day for a given contractor and mix type, differences in contractor for a given mix type, and differences in mix types for a given contractor. The field-produced asphalt analysis was conducted to categorize the dynamic modulus of various hot mix asphalt mixtures using the Asphalt Mixture Performance Tester for the state of South Carolina. Based on the results of this initial study, it is recommended that variations in the dynamic modulus should be accounted for by creating model pavement design inputs for asphalt mixes based on both aggregate source and mix type. When designing pavement structures, the variation of the dynamic modulus of these layers should be of principle concern. Further testing should be completed to further calibrate the MEPDG to conditions found in South Carolina to produce effective, long-lasting, and cost-effective pavement structures.
Hanna, Jared Wellborn, "Investigation of the Variability of Asphalt Dynamic Modulus in South Carolina and Its Sensitivity on Mechanistic Response of Pavements" (2018). All Theses. 2842.