Wordburn hot in-plant asphalt pavement recycling project : final report.

PDFTech ReportFHWA-OR-RD-93-01DOT-FH-15-220Asphalt pavementsAsphalt concreteOverlays (Pavements)Hot in-place recyclingPavement performancePavingAsphalt cementPollutantsAggregatesCostsLoadsOregonOregon. Dept. of Transportation. Research UnitRusnak, James S.Zhou, HaipingNodes, Scott E.Oregon. Department of Transportation. Materials and Research SectionUnited States. Federal Highway AdministrationUS Transportation CollectionIn 1977, the Oregon Department of Transportation constructed a demonstration project using approximately 47,000 tons of stockpiled asphalt concrete (AC) material to overlay a section of pavement in Oregon. The stockpiled AC material was hot in-plant recycled and paved as a conventional hot AC mix. For twelve years of service, the hot in-plant recycled pavement performed well and carried traffic well in excess of the design loadings.The construction details of this demonstration project were documented in an interim report published in 1977. This final report provides various information regrading the project, including the design, construction, and performance of the recycled AC pavement.Based upon the design, construction and performance of this project, the following conclusions were drawn:1) Asphalt concrete material can be hot in-plant recycled and reused for surface paving.2) The properties of slightly aged asphalt cement can be adequately modified through the addition of new "soft" asphalt cements without the incorporation of recycling additives.3) Emissions in recycling are a function of many factors, including mix temperature, grade of new asphalt being added, amount of new aggregate added, amount of water added. and plant production rate.4) Variability in the material properties may be expected. The additions of new asphalt and aggregate may further increase the variability.5) Cost savings and conservation of natural resources can be expected due to the use of the recycled AC materials.6) The new hot in-plant recycled pavement surface was rougher than average new AC pavements.7) The pavement performed well and carried traffic well in excess of the design loadings