A Direct Method for Accounting for Local Weigh-in-Motion Traffic Data in Mechanistic-Empirical Design Procedure for Rigid Pavements

A major concern for state transportation agencies is the calibration and overall localization of mechanistic-empirical pavement design tools to fit state needs. One aspect of this process is the use of locally available traffic data. As part of the development of a state design table for rigid pavement projects, the Minnesota Department of Transportation investigated the use of axle load spectra developed from state weigh-in-motion (WIM) data for projects analyzed using the Mechanistic-Empirical Pavement Design Guide (MEPDG). This paper provides step-by-step details on building the axle load spectra intermediate files to be used by the MEPDG. This methodology can also be adapted to fit the DARWin-ME and ME Design frameworks. The paper also compares the effect of WIM-based axle load spectra on pavement performance versus the effect of the default MEPDG load spectra. In addition, the paper investigates the added value of seasonal traffic data over monthly averages.