Evaluation of rutting and friction resistance of hot mix asphalt concrete using an innovative vertically loaded wheel tester

HMA's rutting characteristics and friction properties play vital roles in defining pavement structural functions and driving safety. This paper developed a novel vertically loaded wheel tester which can uniquely evaluate the rutting potential and friction resistance of eight multi-layer specimens with one experimental set-up. In this study, the rutting and friction resistance with loading cycles for four types of two-layer structures with different mixture combinations were experimentally determined. According to the results, the structures made with the AC-20 mixture as the bottom layer had significantly lower rutting depths; this infers the bottom layer properties have a more pronounced impact on the rutting resistance of the two-layer structure. For the friction resistance, the property of the top layer is more relevant the structure's friction resistance, so use of the SMA-13 mixture in the top layer is favorable. The developed test method was validated with the simulation results using the Pavement ME.