Abstract
<jats:p>This report details a laboratory evaluation, including 1,024 tests, where progression of early-age oxidation was monitored in three airfield asphalt pavements during the first year after construction. The motivation was to provide a foundational understanding of early-age oxidation in airfield asphalt pavements to inform properties of interest to understand optimal timing for applying surface treatments. Testing evaluated near-surface oxidation using traditional methods found in literature (i.e., extracted and recovered asphalt binder properties) and a more novel approach using mixture properties related to distresses due to oxidation (i.e., cracking) that are believed to have greater potential for specifying surface treatment products. Nearly all results indicated meaningful oxidation occurs within the first 12 or 18 months after construction; however, this oxidation is limited to the top 6.3 mm of the pavement surface. In terms of conventional performance grading (PG) assessments, the degree of aging equated to one to two high PG increases in the near-surface as early as 8 months. Bending beam rheometer (BBR) mix beam testing generally agreed with other mixture and binder tests, providing confidence in its validity. From this, m-value emerged as the recommended parameter for analyzing oxidative aging and surface treatment products moving forward.</jats:p>