Abstract
The model for permanent deformation in asphalt concrete (AC) layers used in the Mechanistic–Empirical Pavement Design Guide (MEPDG) was evaluated. Two instrumented flexible pavements were subjected to heavy vehicle simulator testing at three constant temperatures. Permanent deformation modelling was carried out using the MEPDG software v1.003 at the highest accuracy level. The nationally calibrated model resulted in underprediction by 35–45%. Model results were successfully calibrated to fit observation using field calibration factors that increased temperature susceptibility by 45–50% and decreased the dependency of the number of loadings by 30–40%. The field calibration factors should be confirmed by studying existing pavements before being employed. The model did not assess the permanent deformation contribution of each AC layer correctly. Therefore, the model should be refined with further trench studies using in-service pavements.
Acknowledgements
The financial support provided by the Swedish National Road Administration (SNRA) and the Development Fund of the Swedish Construction Industry (SBUF) is gratefully acknowledged. Furthermore, the project relied on supervision and technical support by Dr Safwat Said at the Swedish National Road and Transport Research Institute (VTI), Dr Monica Berntman at Lund University and Dr Richard Nilsson at Skanska Teknik.