Framework to Correlate Hamburg Wheel Tracking Test Results for 4- and 6-in. Asphalt Mix Specimens

The study proposes a threshold value for selecting rut-resistant Marshall-designed bituminous mixtures. It also determines the correlation between 4-in. and 6-in. Hamburg Wheel Tracking Test (HWTT) samples. Samples of 4 in. and 4 in. diameter comprising different binder grades (VG-30, VG-40 and PMB-40) with varying air voids (2.5%, 4% and 7%) were tested using HWTT. The study emphasizes the stronger correlation (R = 0.99; R 2 = 0.98) between 4-in. and 6-in. samples in HWTT results, providing useful information to pavement engineers. The test result also shows that polymer-modified mixtures have better rutting resistance because of their increased viscosity while higher compactive efforts improve resistance by minimizing air voids. Overall, this study underscores the role of performance testing and specification (rut depth = 6.5 mm at 20,000 passes for the Marshall mixtures) in ensuring the long-term performance and durability of pavements. These findings provide valuable guidance for engineers and researchers aiming to increase the performance of bituminous pavements through effective material selection and design strategies.