Study of the surface texture evolution and friction degradation in asphalt pavements during wear process

Asphalt pavements constitute an important part of global transportation infrastructure, and their surface texture directly impact driving safety and comfort. Understanding the evolution of surface texture during wear and its effect on friction degradation is essential for pavement maintenance and safety assessment. This study conducted accelerated wear tests on three typical asphalt pavements (AC-13, SMA-13, and OGFC-13) using a self-developed indoor plate accelerated load wear tester (PALWT). A 3D laser scanner and a dynamic friction tester were used for pavement surface modeling and friction measurement. Based on the ISO 25178-2 standard, areal field parameters and functional volume parameters were innovatively introduced into the pavement wear quantification system to reveal the wear mechanisms of material loss and transfer. Results showed that the macrotexture characteristics of the pavement shifted from rough to flat after wear, with peak features gradually disappearing and texture directionality transitioning from multi-directional to the traffic direction. Wear caused a decrease in material at the surface peaks and valley areas while accumulating material in the core area. The dynamic friction coefficient (DFT40, DFT60, and DFT80) of asphalt pavements initially increased (peaking at around 3000 wear cycles) before decreasing and eventually stabilizing. Open-graded and gap-graded pavements generally outperform dense-graded pavements in terms of friction retention. Peak material volume (Vmp) and valley void volume (Vvv) effectively reflected material redistribution during wear across peak, core to valley, showing a strong correlation with skid resistance. Mean peak curvature (Spc) significantly improves skid resistance at low to medium speeds, while texture aspect ratio (Str) becomes critical under high-speed conditions by ensuring stable multidirectional tire-road interaction.