Field Performance of High RAP Mixtures

The purpose of this project is to revisit high RAP field projects constructed in 2013-2014, and 2019-2021 and assess the long-term field performance. This will provide an indication of life expectancy and will provide data for decisions made regarding the allowance of high RAP mixes. The work will also support ongoing implementation of balanced mix design (BMD). To assess performance to date, automated pavement condition surveys of the field sections will be performed and compiled to collect pavement performance information. Falling weight deflectometer (FWD) testing will be performed to assess structural condition. Ground penetrating radar (GPR) testing will be conducted to verify the pavement thickness. Friction and texture evaluation will be performed to assess safety characteristics of the mixtures. Six-inch diameter road cores will be collected for testing. Density, permeability, asphalt content, and gradation will be determined to characterize the in-service mixture properties and assess changes since construction. IDT-CT (and I-FIT for 2013-2014 mixtures) will be performed for comparison with construction data to assess cracking performance. E* and uniaxial fatigue testing will provide information for structural evaluation to predict pavement life expectancy. Full depth cores will be collected to verify pavement structure and continuity. Binder will be extracted and tested to assess in-service aging and to provide information for structural evaluation to predict pavement life expectancy. Analysis will be performed on the data collected from the field cores, condition assessment, and structural assessment to assess performance. Comparisons with testing performed at construction will be made. Statistical evaluation will be used to investigate the relationships between mixture properties and performance. Performance predictions will be calculated using structural and core data to compare with condition assessment results. American Association of State Highway and Transportation Officials (AASHTO) PavementME and FlexPave are anticipated to be used in structural analysis and performance prediction.