Reclaimed Asphalt Pavement (RAP) - apa-mi.org

1 HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETR eclaimed Asphalt Pavement (RAP) Recycling prevents depletion of natural resources and reduces energy useHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETR eclaimed Asphalt Pavement (RAP )Topics Overview Benefits of using RAP History / Specifications Performance Studies of RAP mixes Recommended practices HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETP avement MillingPlant Waste MaterialAsphalt Pavement RemovalRAP SourcesHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETR ecyclability Asphalt is the No. 1 recycled material 1995 FHWA Report to congress 90 Million tons Reclaimed 80% recycled Asphalt Pavements are 100% recyclable Can re-use binder Return on investmentHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIET020406080100 Percent RecycledFHWA / USEPA Report to Congress, EPA/600/R-93/095.

2 RecyclabilityHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETWhy Recycle RAP into HMA? Best and Highest use Same or better performance as virgin mix Reduces demand for new materials Reduces carbon footprint Contains valuable materials Save $ HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETWhy Recycle RAP into HMA? RAP contains valuable materials : Aggregate ~95% @ $10/ton Asphalt ~5% @ $450/ton Value = $ (minus processing)HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETM aterials savings will depend Virgin binder cost Asphalt content of the mix design Aggregate cost RAP cost (trucking and processing) Asphalt content of the RAP Percentage of RAPHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETE xample Materials Savings for RAP Utilization$300 $400 $500 $- $ $ $ $ $ $ $ $ Savings $/ton%RAPB ased on $15 Aggregate, $9 RAP$6 8 /tonSavingsHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETRAP Givens RAP mixes need to meet the same specs as virgin mixes.

3 Gradation , Asphalt content ( binder ) Aggregate propertiesVolumetric properties ( AV , VMA ) Fines to AC ratio And final Binder Properties( stiffness) HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETB inder Properties Binder in the RAP is aged and much harder than Virgin Binder Need to account for this at higher RAP % Use a softer Asphalt with higher Rap % This will prevent brittle mixes and ensure good performance HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETRAP Specification's History of RAP usage and developmentMDOT RAP specs .HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETM ichigan RAP History Late 1970 s MDOT pilot projects Common practice in the 1980 s Very prescriptive process Many Improvements over 35 years Plant, Process, Asphalt TechnologyHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETM ichigan RAP History 1990 MDOT Standard Spec Book.

4 RAP specified based on the % RAP used in the mix (% of total weight of mixture) If 15 % RAP or less - no change in the AC grade If greater than 15 to 50 % - may require a change in AC grade HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETNCHRP 9-12 Mix design Guidelines Binder Grade Selection 15% 25% AASHTO M323( superpave Mix design ) HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETAASHTO SPECIFICATIONS 0 to 15% No change in base binder grade 15 to 25% Reduce one grade >25% Binder evaluation (recovery, blending, etc.)HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETMDOT RAP SystemIntroduced in 2002 3 Tier system Determines the grade of binder used in the mix Based on the amount of the total binder that comes from the RAP ( % ) Tier 1: 0 17% Tier 2: 18 27% Tier 3: 28%HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETMDOT RAP SystemIntroduced in 2002 Spec language : Contribution of RAP binder toward the total binder, by weight RAP binder by weight of the total binder in the mixture Or National terminology : Binder replacement HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETB inder Replacement Calculation Binder Replacement, % = (A X B) 100%C Where:A = RAP percent binder contentB = RAP percent in mixtureC = Total percent binder content in mixtureHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETB inder Replacement Calculation Example.

5 For a mix containing 20 % RAP A = % (binder in the RAP)B = 20 % (RAP in mixture) C = % (Total binder in mixture)Binder Replacement = (A X B) 100%C = X 100% = .90 / x 100% = %HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETMDOT RAP Spec 03SP501 (G) 2002 HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETFor Marshall and superpave mixes:Tier 1 - 0% to 17% RAP (binder replacement) Use same grade ( design binder grade) Tier 2 - 18% to 27% RAP (binder replacement) Use one grade lower for the high temperature If design binder grade is PG58-28, Use RAP Spec 03SP501 (G) 20022002 thru 2010 HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETFor Marshall and superpave mixes:Tier 3 - 28% RAP (binder replacement) Use a blending chart to determine the high and low temperature values Restrictions (on leveling and top course mixes):E3 and E10 mixes maximum 17 % RAP E30 and E 50 mixes - maximum 14 % RAP MDOT RAP Spec 03SP501 (G) 20022002 thru 2010 HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETMDOT RAP Spec 12SP501 (G) 2011 For superpave mixes only2011 HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETFor superpave mixes only:Tier 1 - 0% to 17% RAP (binder replacement) Use same grade ( design binder grade)Tier 2 - 18% to 27% RAP (binder replacement) At least one grade lower for the low temperature Optional- lowering the high temperature one grade If design binder grade is PG58-22, Use PG58-28, or 52-28 No binder grade change for: shoulder or temporary road mixes, LVSP, E03 and E1 mixtures used as leveling or top course.

6 MDOT RAP Spec 12SP501 (G) 20112011 to PresentHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETFor superpave mixes only:Tier 3 - 28% RAP (binder replacement) Use a blending chart to determine the high and low temperature values Restrictions (on leveling and top course mixes):E3 and E10 mixes maximum 17 % RAP E30 and E 50 mixes - maximum 17% RAP MDOT RAP Spec 12SP501 (G) 20112011 to PresentHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETMDOT RAP Spec 12SP501 (E) 2011 HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETFor Marshall mixes only:Tier 1 - 0% to 17% RAP (binder replacement) Use same grade ( design binder grade) Tier 2 - 18% to 27% RAP (binder replacement) Optional - lowering the high temperature one grade Except in the Metro Region: Must lower the high temperature one gradeIf design binder grade is PG 64 -22, Use PG 58-22. No binder grade change for: shoulder or temporary road mixes MDOT RAP Spec 12SP501 (E) 20112011 to PresentHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETFor Marshall mixes only:Tier 3 - 28% RAP (binder replacement) Use a blending chart to determine the high and lowtemperature values MDOT RAP Spec 12SP501 (E) 20112011 to PresentHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETR eclaimed Asphalt Pavement in Asphalt Mixtures: State of the Practice State-of-the-practice information on including higher amounts of RAP in Asphalt mixtures.

7 The performance and life of Pavement containing up to 30 percent RAP is similar to virgin pavements with no RAP. Publication No. FHWA-HRT-11-021 April 2011 HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETP erformance of High RAP Content MixesFrom Presentation byRandy WestDirector, NCATHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETP erformance of High RAP Content MixesHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETP erformance Study of Asphalt Pavements with 30% RAP LTPP SPS-5 Pavement sections 18 states and Canadian provinces At least 30% RAP used in recycled mixes Projects range in age from 6 to 17 yrsHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETSPS-5 Project LocationsHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETA nnual Performance Data International Roughness Index (IRI) Rutting Fatigue Cracking Transverse Cracking Longitudinal Cracking Block Cracking Raveling HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETLTPP SPS-5: RAP vs.

8 Virgin Four comparison pairs per project (location) 2 overlay, no mill 2 overlay with mill 5 overlay, no mill 5 overlay with mill 504 comparisons: graphed, tabulated differences, statistical analysesHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETA labam a R ut D epth - no m ill, 2" overlay0246810125/7/901/31/9310/28/957/2 4/984/19/011/14/0410/10/06D ateRut Depth, mmV irginR A P H ot-M ix R ecycled A sphalt Concrete& Asphalt C oncrete O verlayAlabam a IRI - no m ill, 2" , m/kmVirginRAPHot-Mix Recycled Asphalt Concrete& Asphalt Concrete O verlayAlabam a Fatigue - no m ill, 2" overlay0501001502002503003504004505005/7 /901/31/9310/28/957/24/984/19/011/14/041 0/10/067/6/09 DateArea of Fatigue Cracking, m2 VirginRAPHot-M ix Recycled Asphalt Concrete& Asphalt Concrete O verlayHMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETS tatistical Analyses Paired t-tests Compared section pairs (30% RAP to virgin mix)

9 For each location, thickness, and surface preparation Since each location is subject to same traffic and environment, these effects are muted Alpha = (90% confidence interval)HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETS ummary of Statistical AnalysesDistressParameterVirgin Performed Better than RAPRAP Performed Better than VirginInsignificant Difference Between RAP and VirginRAP Performed Equal or Better Than VirginIRI42391958 Rutting33293867 Fatigue Cracking29106171 Long. Cracking15107585 Transverse Cracking32155368 Block Cracking319697 Raveling7157893 NCAT Study 2009 HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETO ther Performance Studies on RAP Mixes Discussed in : Reclaimed Asphalt Pavement in Asphalt Mixtures: State of the PracticePublication No. FHWA-HRT-11-021 April 2011 HMA America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETO ther Performance Studies on RAP MixesFrom Publication No.

10 FHWA-HRT-11-021 April 2011 50. Ayers, M., et al. (2009). Impact of design Features on Pavement Response and Performancein Rehabilitated Flexible and Rigid Pavements, Report No. FHWA-HRT-10-066, FederalHighway Administration, Washington, Hong, F., et al. (2010). Long-Term Performance Evaluation of Recycled Asphalt PavementResults from Texas: Pavement Studies Category 5 Sections from the Long-Term PavementPerformance Program, Transportation Research Record 2180, Transportation ResearchBoard, Washington, Zaghloul, S. and Holland, (2008). Comparative Analysis of Long-Term FieldPerformance of Recycled Asphalt in California Environmental Zones, TransportationResearch Record 2084, Transportation Research Board, Washington, Musselman, J. (2009). High RAP Performance in Florida, HMA Recycling Expert TaskGroup, Department of Transportation, Washington, DC. Obtained from: Site last accessed January 4, America s Most Recycled ProductSMOOTH | DURABLE | SAFE | QUIETS tatistical Analysis ofPerformance of RecycledHot Mix Asphalt Overlaysin Flexible PavementRehabilitationFHWA Publication No.