1. Best Practices on the Use of RAS
Victor (Lee) Gallivan – FHWA
Recycling Coordinator
Office of Asset Management,
Pavement and Construction
Denver, Colorado
November 8, 2013

2. Todays Outline References Handling of RAS Grinding of Shingles
Plant Operations
Field Operations
Rule of Thumb for RAS Mixtures

3. Reclaimed Asphalt Shingles (RAS) Industry Guidance
CMRA
NAPA
Construction Materials Recycling Association (CMRA)
Construction Materials Recycling Association (CMRA)

4. References CMRA Best Practices Guide for Shingles, 2007
NAPA IS 136: Guidelines for the use of reclaimed asphalt shingles asphalt mixtures, 2009
AASHTO Standards, PP15/MP53 (being revised)
NCAT Report 12-05: Effect of Rejuvenators on Performance Properties of HMA mixtures with High RAP and RAS contents, June 2012
TPF - 5(213): Performance of Recycled Asphalt Shingles in Hot Mix Asphalt, Iowa State University, August 2013

5. Handling of Asphalt Shingles
Source Separating the incoming flow of shingles. Separate out the non-shingle debris before loading and/or tipping at the shingle recycling plant.
Keep all non-shingle debris separated. Initial Automatic sorting excellent practice to start with then follow with manual inspection and/or sorting of both post-manufactured and post-consumer shingles.
Shingle recyclers should develop a comprehensive dust control and management plan, e.g. include dust control devices (e.g., enclosed grinding chambers with pneumatic conveyance, air separation, bag house filters, and dust containment) and continuously water the inflow of the shingles.
Conformance to regulatory requirements, have a formal plan.

6. Grinding of Shingles Industrial Grinders works well on all shingles
Post-manufactured shingles delivered in roll-offs can include shingle globs, metal or other objects that could damage the industrial grinders.
Grinders need to be fitted with cross-bar magnets to effectively remove deleterious materials.
Sizing of shingles to 3/8 in. max –critical 100 % passes the 9.5 mm (3/8-in.) sieve
Control deleterious materials – critical 1% of mass and 0.5% max Non-Metallic

7. Plant Operations Quality Control (QC) Address Shingle Storage Storage
Handling
Include frequent testing of RAS materials , e.g., bulk specific gravity, gradation, binder content
Drum Mixing Temperatures
Address Shingle Storage
Protect the RAS from conglomerating due to direct sunlight;
Protect the stockpiles from rain to keep the moisture content down;
Protect the RAS piles from the wind that can cause fines blowing off the stockpile
Protect the RAS piles from cross contamination

8. Plant Operations - Continued
Plant Temperatures
Shingles need higher temperatures to remove moisture and for blending of RAS binder with virgin binder
But Higher temperatures accelerate RAS aging during construction
Potential conflicts with some WMA procedures
Introduction of Shingles into Drum
Introduced in the HMA plant through a separate recycling bin and into the RAP collar on the drum.
Load cells or weigh belts measure the amount of RAS as it is metered into the collar.
Load RAP over the RAS on the same conveyor belt to eliminate the blowing of the finer RAS.

9. Field Operations ≠ Major
Contractor needs good QC in:
Trucking
Transfer
Paving
Rolling
W/RAS, mixtures are stiffer and TOC is more critical.

10. Rule of Thumb
3-5 % RAS or 20 % RAP binder would be the maximum amount of recycled material allowed without requiring a low temperature grade bump (6°C) in the base binder.
This corresponds to a 14 % binder replacement when using RAS and a 20 % binder replacement when using RAS with RAP

11. Thank you…For More Information…
Victor (Lee) Gallivan, PE
Recycled Material Program Coordinator
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RAS has successfully been used with HMA, WMA, GTR, SMA mixtures