Analysis of ACR-PCR to evaluate bearing capacity of airport cement concrete pavements using field-measured data

To advance the understanding of the aircraft classification rating-pavement classification rating (ACR-PCR) method for evaluating the bearing capacity of airfield cement concrete pavements, this study establishes a comprehensive ACR-PCR evaluation database for such pavements at China's transport airports. This effort is grounded in the national pavement strength-report updating program and employs the civil aviation administration of China-pavement classification rating (CAAC-PCR) software, alongside standardized principles and procedures for parameter acquisition. A total of 190 runways commissioned over the past two decades are selected as the analytical sample, and the distribution characteristics of their structural parameters are statistically examined. On this basis, the sensitivity of PCR to structural parameters and its variation patterns are investigated in detail, while the influences of traffic volume and aircraft mix are also assessed. Furthermore, the distribution characteristics of PCR are statistically summarized, and a comparative analysis is conducted between the ACR-PCR and the aircraft classification number-pavement classification number (ACN-PCN) methods. The results indicate that slab thickness and flexural strength are the most sensitive parameters governing PCR, followed by base-layer parameters, whereas subgrade parameters exert a comparatively minor influence. PCR decreases with increasing traffic volume, with the rate of reduction gradually diminishing; its value is governed by both the aircraft with the largest ACR in the fleet mix and the maximum cumulative fatigue damage factor induced by the traffic mix. For rigid pavements at Chinese airports, as the airfield area class upgrades from 4C and 4D to 4E and 4F, the maximum PCR values remain generally comparable, while the minimum, median, and mean values show a consistent upward trend. Additionally, PCR on class B subgrade is slightly higher than that on class A subgrade. Compared with the ACN-PCN method, the ACR-PCR approach exhibits greater sensitivity to cumulative fatigue effects and yields more conservative evaluations, yet both methods demonstrate consistency in identifying aircraft requiring load restrictions.