Date of Graduation
5-2025
Document Type
Thesis
Degree Name
Bachelor of Science in Civil Engineering
Degree Level
Undergraduate
Department
Civil Engineering
Advisor/Mentor
Braham, Andrew
Abstract
Contemporary asphalt research aims to strike a balance between rutting and fatigue cracking to enhance pavement longevity. The performance of asphalt mixtures is influenced by factors such as aggregate gradation and asphalt film thickness. Although gradation typically adheres to the mid-gradation method, asphalt film thickness is included in certain mix designs, even though it is not universally regarded as an essential parameter. Nonetheless, no current method primarily addresses both gradation and asphalt film thickness together. In this research, aggregate gradations were designed using the principles of Bailey’s method along with various other criteria such as control points, the dust to binder ratio, and the maximum density line. The preliminary mix design was carried out based on an asphalt film thickness of 9 ± 3 microns, and the binder content was determined accordingly. The results indicated that average binder content varied from 3.6% for an AFT of 6 microns in both HMA and BHMA gradations to 6.4% for an AFT of 12 microns in the HMA gradations. For both HMA and BHMA gradations, as the AFT increased, the standard deviation increased from 0.3 to 0.5 microns and the coefficient of variation also rose by 0.009, indicating greater variability in binder content with higher AFT values. Using ARDOT weighted average prices, the Bailey method of gradation shows the potential to reduce the price per ton of asphalt by 2.2% to 5.1% for HMA mixes and 0.4% to 1.0% for BHMA mixes, depending on the target film thickness and binder grade. In summary, the results of this study indicated that Bailey’s method could decrease the quantity of asphalt binder in an asphalt mixture, which could reduce the costs of asphalt production.
Keywords
Bailey's method, Asphalt film thickness, Aggregate gradation, Asphalt pavement
Citation
Quinn, L. (2025). Enhancing Asphalt Mix Design through Film Thickness and Bailey’s Gradation Method. Civil Engineering Undergraduate Honors Theses Retrieved from https://scholarworks.uark.edu/cveguht/87
