Calibrating Full-Scale Accelerated Pavement Testing Data Using Long-Term Pavement Performance Data

Accelerated Pavement Testing (APT) has always been conducted with the objective of improving the understanding of real pavements under real traffic and environmental conditions. While APT provides an accelerated view of some of the major structural behavior to be expected from tested pavements, and while various environmental conditions can typically be simulated during APT, it is important to link the results obtained to real world pavement behavior to enable outputs from APT to be calibrated for use in general pavement design and analysis. One way of conducting this type of calibration is to conduct Long-Term Pavement Performance (LTPP) evaluations on similar pavements to those tested under accelerated conditions and to relate this information to the APT data to calibrate the them for general use (inclusive of normal traffic and environmental conditions). This paper evaluates six years of APT and LTPP data from two road sections in South Africa. The results of the APT tests are compared to the LTPP data and the pavement behavior models obtained from the APT calibrated to real-world outputs. Various concepts required to conduct these calibrations are discussed and the general procedure is reported. It is recommended that more LTPP sections be assessed in conjunction with APT, which should result in more realistic application of the APT data in that the effects of more real-time environmental and traffic applications will be incorporated into calibrated models.