Available at: http://digitalcommons.calpoly.edu/theses/467
Date of Award
MS in Civil and Environmental Engineering
Civil and Environmental Engineering
Ashraf M. Rahim
Moisture damage in asphalt pavement has always been a problem for drivers, bicyclists, and pedestrians. The primary objective of this study is to evaluate moisture susceptibility of Hot-Mix Asphalt (HMA) and to investigate mitigation techniques using different antistripping agents. Three types of antistripping agents were used in this research investigation. Two of which are chemical based and the other is hydrated lime. The two types of liquid antistripping agents used in this study include Arr Maz CC LOF-6500 and Arr Maz CC XL-9000. These two liquid antistripping agents were tested at 0.25%, 0.50%, and 0.75%. Hydrated Lime was tested at 1.0%, 1.5%, and 2.0%. The binder used in this study is Asphalt Performance Grade (PG) 64-16 provided by Oxnard Refinery. The crushed stone aggregate used in this study was provided by Cal Portland. This study follows the guidelines of standardized AASHTO, ASTM, and SuperPave mix design for all preparation and test procedures. A total of 120 4-inch by 2.83-inch core specimens with void ratios between 6 to 8 percent were created to test for moisture susceptibility in accordance with the Modified Lottman Test, which tested for Indirect Tensile Strength and Immersion Compression Test, which tested for Compression Strength and Elasticity. During the test, half of these specimens were placed in a hot water bath for 24 hours to condition the sample to represent field performance and the other half were unconditioned. Based on the results, the best liquid antistripping agent is XL-9000 at 0.50% and hydrated lime is most efficient at a dosage rate of 1.5%. The best performing antistripping additive for the value is hydrated lime at 1.5%.