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

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

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

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

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.

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

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

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.

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

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

Thank you…For More Information… Victor (Lee) Gallivan, PE Recycled Material Program Coordinator Victor.Gallivan@dot.gov Ph: 317-226-7493 Cl: 317-605-4704 RAS has successfully been used with HMA, WMA, GTR, SMA mixtures