Interface contact properties in asphalt pavement using 3D laser scanning technology

AbstractExisting research on pavement interlayer bonding has mainly focused on bonding materials and external factors, neglecting the upper and lower interlayer surface characteristics. This study aims to analyze the contact conditions between these surfaces, developing a numerical model to reveal their properties. Five double-layered asphalt systems, including dense-graded asphalt concrete (AC), open-graded friction course (OGFC), and stone mastic asphalt (SMA) mixes, were examined using a nondestructive interlayer separation method and 3D laser scanning. Three indices were proposed to assess interlayer surface characteristics in both 2D and 3D domains. Shear strength tests at room temperature were also conducted, revealing that AC-only systems had lower surface mismatch at the layer interface compared to SMA or OGFC mixes. The study concludes that surface mismatch decreases with greater differences in aggregate coarseness, and systems with significant mismatch gaps have lower shear strength. These findings provide valuable insights for designing durable pavement structures.KEYWORDS: Asphalt pavementinterlayer bondingmismatch gapinterface modelsurface characteristicsinterface shear strength Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThis work was supported by National Natural Science Foundation of China [Grant Number 51878574]; Sichuan Province Science and Technology Support Program [Grant Number 2021JDTD0023]; Fundamental Research Funds for the Central Universities, SWJTU [Grant Number 2682022CX002].