Development of Local Calibration Factors and Design Criteria Values for Mechanistic-Empirical Pavement Design

VTRC2015A mechanistic-empirical (ME) pavement design procedure allows for analyzing and selecting pavement structures based on predicted distress progression resulting from stresses and strains within the pavement over its design life. The Virginia Department of Transportation (VDOT) has been working toward implementing ME design by characterizing traffic and materials inputs, training with the models and design software, and analyzing current pavement designs in AASHTOware Pavement ME Design software.

This study compared the measured performance of asphalt and continuously reinforced concrete pavements (CRCP) from VDOT’s Pavement Management System (PMS) records to the predicted performance in AASHTOware Pavement ME Design. Model coefficients in the software were adjusted to match the predicted asphalt pavement permanent deformation, asphalt bottom-up fatigue cracking, and CRCP punchout outputs to the measured values from PMS records. Values for reliability, design life inputs, and distress limits were identified as a starting point for VDOT to consider when using AASHTOware Pavement ME Design through consideration of national guidelines, existing VDOT standards, PMS rating formulas, typical pavement performance at time of overlay, and the data used for local calibration.

The model calibration coefficients and design requirement values recommended in this study can be used by VDOT with AASHTOware Pavement ME Design as a starting point to implement the software for design, which should allow for more optimized pavement structures and improve the long-term performance of pavements in Virginia.

Authors: Bryan Smith, P.E., and Harikrishnan Nair, Ph.D., P.E.