Laboratory and Field Evaluation of Performance-Engineered Stress Relief Courses in Nevada
[Thesis]
Warrag, Ahmed
Hajj, Elie
University of Nevada, Reno
2020
145 p.
M.E.
University of Nevada, Reno
2020
Asphalt Concrete (AC) overlay is one of the most common technique used by Nevada Department of Transportation (NDOT) to maintain and repair aged and deteriorated flexible pavements in Nevada. A major challenge associated with overlays is the reflection of the cracks from the underlying pavement due to the combined effect of traffic and environmental conditions. In 2006 NDOT initiated a three-phase study to mitigate reflective cracking that resulted in the development of an engineered stress relief course (ESRC) with performance-based mix design specifications to be used as an interlayer between the existing AC layer and the AC overlay. Consequently, the ESRC was used in three NDOT demonstration projects constructed in 2015, 2017, and 2019. In addition a project was constructed in 2016 through The Community Services Department of Engineering and Capital Projects in Reno, Nevada. This research aims to evaluate the laboratory and field performance of the ESRC in the demonstration projects. Moreover, it aims to determine the necessary information to predict the long-term performance of the ESRC. The constructability of the ESRC was closely monitored, and extensive laboratory evaluation was conducted to assess the ESRC stability and resistance to cracking. The falling weight deflectometer (FWD) testing in conjunction with field core samples were used to characterize the pre-overlay in order to be used in the AASHTOWare Pavement ME Design software version 2.5.5 to predict the long term performance of the ESRC test sections.