Materials characterization and analysis of the Marquette Interchange HMA perpetual pavement

Abstract

This project focused on the characterization of materials used to construct the Hot Mix Asphalt (HMA) perpetual pavement within the Marquette Interchange and on the analysis of collected pavement response data to investigate the interactions between materials, environment, and traffic loadings. While these pavements are designed for a service life in excess of 50 years, to date there is insufficient field data to confirm this performance expectation. To help bridge this knowledge gap, this study included a mechanistic-empirical appraisal of the HMA perpetual pavement to provide predictions of key performance indicators over a fifty year service period. Laboratory testing was conducted following appropriate AASHTO testing protocols to provide valuable data to characterize the HMA, unbound aggregate and unbound soil pavement layers. These data were used to develop Level 1 HMA inputs to the current version 1.003 of the Mechanistic-Empirical Pavement Design Guide (MEPDG) and to better characterize the unbound aggregates and soils during Level 3 analysis. Weigh-In-Motion (WIM) data obtained as part of WHRP Project 0092-06-01 were analyzed to develop site-specific inputs characterizing the heavy axle loading spectra using this pavement facility. Pavement performance predictions were developed using the MEPDG v1.003 and stand-alone KENPAVE software. Consideration was given to both free flow (55 mph) and congested (15 mph) traffic conditions. Using a combined traffic approach, pavement distress at the 90% reliability level was projected to 50 years of trafficking. Only top-down fatigue cracking, which should be confined within the uppermost 0.5 in. of the pavement surface, is projected to exceed typical design limits. This projected distress will easily be corrected using the standard practice of mill and relay. Furthermore, after 50 years of service the 90% reliability level for bottom-up fatigue damage is expected over 15% of the total lane area, or 30% of the loaded wheel paths, which is well below typical design limits of 25% and 50%, respectively. All analysis results indicate the constructed HMA perpetual pavement should meet or exceed performance expectations.