Local calibration of MEPDG for Superpave Pavements in Ontario : Enhance rutting calibration and preliminary study on IRI model

The AASHTO Mechanistic-Empirical Pavement Design Guide requires local calibration to account for local conditions, materials, and engineering practices. Previous local calibration studies in Ontario focused mainly on permanent deformation models for pavement rutting. The objectives of this study are twofold. First, to provide an enhanced calibration for the rutting models by using more vigilantly cross-verified input data and updated observed rutting data. Second, to perform a trial calibration for the international roughness index (IRI) model by considering three different calibration methods. Cracking models calibration, being performed by another colleague, has not yet been finalized; therefore, the IRI model calibration cannot be finalized in this study. Based upon 63 Superpave sections, the local calibration coefficients were found to be βAC = 1.7692, βT = 1.0, βN = 0.6262, βGB = 0.0968 and βSG = 0.2787 , which reduced the standard deviation of residuals to a value of 1 mm. The IRI calibration study found that the initial IRI value plays an important role in the calibration. Keywords: International Roughness Index (IRI) model; local calibration; Mechanistic-Empirical Pavement Design Guide (MEPDG); rutting model; Superpave.