Shingles Recycling: Quality Assurance / Quality Control A
Presentation at the Sacramento RMRC Workshop on Tuesday, April 11,
2006 Presenter: Dan Krivit Dan Krivit and Associates Slide 2
Recycled Materials Resource Center www.rmrc.unh.edu Slide 3
Presentation Outline 1) Material Introduction 2) Engineering
Properties 3) Applications and Performance 4)States Using Shingles
in HMA 5) Specifications 6) Testing and Design Procedures 7)
Further Information 8) Summary Slide 4 Presentation Outline
[Modified from presentation already in your big books! Make sure to
get all additional inserts: AASHTO spec Bibliography SWMCB packet
Slide 5 Material Introduction Slide 6 Definitions Manufacturers
Asphalt Shingle Scrap Tear-Off Asphalt Shingle Scrap Recycled
Asphalt Shingles (RAS) (Crushed & screened) Slide 7 History 15
years + Multiple research studies in lab and field Manufacturer
shingle scrap in hot-mix asphalt best known, most accepted practice
Still relatively new application Slide 8 Engineering Properties
Slide 9 Composition of Residential Asphalt Shingles Slide 10
Composition of Asphalt Roofing Shingles Asphalt binder content: 20
to 40% Aggregate material: 40 to 60% Fibrous reinforcement: 20%
Slide 11 Recent Composition Weight Ranges of Typical Asphalt
Shingles 32 to 42% Coating filler (limestone or fly ash) 28 to 42%
Granules (painted rocks & coal slag) 16 to 25% Asphalt 3 to 6%
Back dust (limestone or silica sand) 2 to 15% Mat (fiberglass,
paper, cotton rags) 0.2 to 2% Adhesives (modified asphalt based)
Slide 12 Applications and Performance Slide 13 Multiple
Applications HMA Aggregate (gravel) Dust control Cold patch Ground
cover Fuel New shingles [Most Proven] Slide 14 Factors Affecting
HMA Performance Aggregate gradation of RAS Properties of final
blended binder content within the HMA as affected by: RAS asphalt
binder Virgin binder Slide 15 Factors Affecting HMA Performance
(continued) Location RAS is incorporated into HMA Temperature
Moisture content of RAS and other aggregates Retention time in HMA
drum Slide 16 Source: Newcomb, April 2003. Slide 17 Slide 18 Slide
19 Slide 20 Slide 21 Slide 22 Slide 23 Engineering Performance
Advantages Reduce need for virgin binder Add fibrous reinforcement
Modify PG grade binder High temp performance Reduce landfill needs
3-11 Slide 24 Potential Benefits * (* Manufacturers RAS) Cracking
resistance Rutting resistance Conservation of landfill space
Source: Paul Lum, Lafarge Construction Materials Ltd., April 13,
2003. Slide 25 Challenges Need for improved grinding and handling
Blending and storage Continued research into engineering effects of
RAP and RAS on AC binder content Quality control and quality
assurance Slide 26 Barriers to Shingle Recycling Economic reasons
Policy and regulatory compliance Environmental concerns Technical
reasons Public sentiment ----------- (Note:These barriers may be
real or perceived!) Slide 27 Engineering Performance Disadvantages
Hotter mix requirements Stiffer mix Possible contamination 3-12
(Justus, September 2004) Slide 28 Source: Lum, April 2003. Slide 29
Slide 30 Slide 31 Slide 32 Slide 33 Slide 34 Slide 35 Asphalt
Shingles in HMA Missouri DOT Experience Joe Schroer, PE
Construction and Materials Division March 30, 2005 Slide 36 In The
Beginning Approached by Pace Construction and Peerless Landfill
MoDOT Not Using RAP in Mixtures Deleterious Material Stiffness of
Asphalt in Shingles Slide 37 First Look The Ex Factor Exhaustive
Literature Search Exclusion of Tear Offs in States Allowing
Manufacturing Waste Extra Clean Material Contained Little
Deleterious Matter Exceptionally Stiff Asphalt Extracted from
Shingles Slide 38 Shingle Components Asphalt 20%-40% Stiffen
Roadway Asphalt Aggregate 30% Good Stuff Fiberglass or Paper Mat
30% No Harm if Well Dispersed Slide 39 MoDOT Goals Engineering
Properties First Harmful Effects of Deleterious Material Asphalt
Binder Properties Traffic Safety Nails, etc. If Everything Else
Works Out, Landfilling is Reduced Slide 40 Why Should We Pursue
Shingles? High Asphalt Content Granules Are Hard and Durable
Recycling CO$T Slide 41 Concerns How Will Deleterious Material
Affect the Mixture Can the Low Temperature Grading be Maintained at
Various Blending Ratios Slide 42 Asphalt After Blending with
Shingle Asphalt Resist Rutting Resist Fatigue Cracking Resist
Cold-Weather Cracking Slide 43 Asphalt Grades High Temperature for
Rut Resistance Low Temperature for Fatigue and Cold Weather
Performance Performance Graded = PG PG 64-22 (PG Sixty-four Minus
Twenty-two) High Temp 64C (147F) Low Temp 22C (-8F) Slide 44
Asphalt Modifications Require PG 64-22 Stiffer at High Temperature
OK Stiffer at Low Temperature Use Lower Percentage of Shingles Use
Softer Roadway Asphalt Slide 45 Deleterious Evaluation
Specification for Aggregate 0.5% Other Foreign Material Sticks, mud
balls, deer fur, etc. Shingle OFM Approximately 3% Total Slide 46
Deleterious Material Nails Wood Plastic Cellophane Paper Fiber
Board Slide 47 Trial by Fire Slide 48 No Difference Visually
Standard Mixture Tests Placement Slide 49 Big Difference Rut
Resistance Cold Temperature Tests OFM in Mixture Slide 50 Can
Tear-Off Shingles be Used? Allowance in OFM Due to Small Percentage
of Shingles and Trial Mixture Start with Softer Roadway Asphalt
Slide 51 Where Are We? The Ex Factor 2 Extrinsic Material Allowance
Raised 3.0% Total 1.5% Wood Expect PG 64-22 met w/ PG 58-28 Extra
grades optional w/ testing Examining various proportions and
asphalts Exuberant Contractors Slide 52 U of M Lab Data: Missouri
Samples Prof. Mihai Marasteanu, U of M Dept. of Civil Engineering
Preliminary results as of 4-6-2006 Report with Mn/DOT lab data to
be released soon Slide 53 MO: Mix Stiffness @ 100sec. (PG 64-22)
Slide 54 MO: Mix Stiffness @ 100sec. (PG 58-28) Slide 55 MO: Mix
Stiffness @ 500sec. (PG 58-28) Slide 56 MO: Tensile Strength (PG
64-22) Slide 57 MO: Tensile Strength (PG 58-28) Slide 58 Mn/DOT lab
data Jim McGraw, Director of Mn/DOTs Chemical Lab, Maplewood, MN
Preliminary lab data as of Thursday, April 6, 2006 Report with U of
M lab data, including Mo/DOT samples, to be released soon Slide 59
New Minnesota Lab Study Funded by OEA Co-sponsored by Mn/DOT
Comparing manufacturer RAS to Tear-Off RAS Mn/DOT to conduct PG
extractions U of M Civil Engineering to conduct indirect tensile
strength tests Slide 60 MN: Gradation of RAS Tear Off Slide 61 MN:
Gradation of RAS Manufacturers Slide 62 MN: Gradation of RAP Slide
63 MN: Asphalt Content of RAS Slide 64 MN: PG Grade of RAS Slide 65
Slide 66 MN: Deleterious in RAS Slide 67 U of M Lab Data: Minnesota
Samples Prof. Mihai Marasteanu, U of M Dept. of Civil Engineering
Preliminary results as of Thursday, April 6, 2006 Report with
Mn/DOT lab data to be released soon Slide 68 MN: Mix Stiffness
[GPa] @ 100 sec. 0.2 2.7 10.0 0.5 5.0 13.5 0.2 5.5 8.2 0 4 8 12 16
0-10-20 Temperature [ o C] Stiffness [GPa] 20% RAP 15% RAP + 5%
Tear-off 15% RAP + 5% Manufactured Slide 69 MN: Mix Stiffness [GPa]
@ 500 sec. Slide 70 MN: Tensile Strength [MPa] Slide 71 MN vs. MO:
Mix Stiffness [GPa] @ 100 sec. Slide 72 MN vs. MO: Mix Stiffness
[GPa] @ 500 sec. Slide 73 States Using RAS Slide 74 (Justus,
September 2004) Slide 75 Slide 76 Slide 77 Western States
California Montana Texas Oregon Slide 78 Source: Ordorff, March
2005 Slide 79 Slide 80 Source: Ayres, April 2003. Slide 81 Other
States Specifications [and Experiences] Slide 82 Georgia -
Manufacturing and Post Consumer Shingle - Mixing Permitted -100%
passing the inch Sieve - Maximum 5.0% RAS permitted - Gradation -
meet requirements of Mix Design - No foreign material ( paper,
roofing nails, wood, and metal flashing) - Free of Asbestos when
tested with Polarized Light Microscopy. Test every 1000 Tons
(Justus, September 2004) Slide 83 Manufacturing Shingle Waste Only
100% passing the inch Sieve Maximum of 5.0% RAS permitted Gradation
meet the requirements of the mix design Performance grade of virgin
asphalt binder based on the properties of the shingle asphalt
binder No limits on deleterious materials or asbestos Minnesota
(Justus, September 2004) Slide 84 New Jersey Manufacturing Shingle
Waste Only 100% passing the inch Sieve Maximum of 5.0% RAS
permitted Gradation meet the requirements of the mix design No
limitations on deleterious materials or asbestos (Justus, September
2004) Slide 85 North Carolina Manufacturing Shingle Waste Only 100%
Passing the inch Sieve Maximum of 6.0% RAS permitted Gradation meet
the requirements of the mix design No Limitations on the presence
of deleterious materials or asbestos (Justus, September 2004) Slide
86 Texas DOT Texas DOT- State Highway 31 Corsicana, Navarro County
1997 - 2 x 1,000 foot sections post consumer RAS - 2 x 1,000 foot
sections manufacturing RAS - 2 x 4,000 foot sections Control
Mixture The Mix Design required 5% Post Consumer RAS and 5%
Manufacturing RAS All three Mixes required 5% Stripping Agent 7-2
(Justus, September 2004) Slide 87 Texas DOT: Constituents of
Roofing Shingles Used in Test Project Tear-Off Shingles
Manufacturers Shingles Asphalt Cement (%) Mineral Filler (%)
Viscosity of Asphalt @ 140F (Poise) Penetration @ 77F 25 39 3778 24
22 50 1223 37 (Justus, September 2004) Slide 88 Texas DOT-
Conclusions Shingle binder content does not relate to reduced
quantity of virgin binder Felt appeared to migrate to the surface
Processed shingles (RAS) did not clump Post consumer shingle more
difficult to handle (Justus, September 2004) Slide 89 Smoothness,
stability, moisture susceptibility, creep indicated similar
characteristics among the three mixes. 1999 Falling Weight
Deflectometer testing showed performance agreement among the three
mixes. Visual evaluation shows no apparent distress in any of the
mixes. Texas DOT - Conclusions (Justus, September 2004) Slide 90
Texas (old proposed specification): Both Manufacturing and Tear-Off
Shingle Waste permitted 100% passing the inch Sieve Gradation meet
the requirements of the mix design No Contamination - dirt or other
objectionable materials No harmful quantities of asbestos when
tested according to EPA guidelines Slide 91 New TCEQ Memo March 20,
2006 Manufacturers RAS in HMA approved * Tear-offs not approved
depending on stack testing results and subsequent review of impacts
* Must follow same procedures as RAP into HMA Slide 92 Testing and
Design Procedures Slide 93 American Association of State and
Highway Transportation Officials (AASHT0) Recycled asphalt shingles
specification and practice was approved by the Subcommittee on
Materials (SOM) August 2005 Slide 94 AASHTO: Subcommittee on
Materials THOMAS E. BAKER (360) 709-5401 Tumwater, Washington
[email protected] Slide 95 Review of AASHTO Specification
Subcommittee on Materials (SOM) Both manufacturers and tear-offs
allowed 100% passing the inch Sieve Maximum addition rate
contractor option Gradation and volumetrics must meet the
requirements of the mix design Slide 96 AASHTO Specification
(continued) Addition rates (Section 7): If RAS binder if greater
than 0.75 percent, the virgin asphalt binder and RAS binder
combination shall be further evaluated to ensure PG requirements
Slide 97 AASHTO Specification (continued) Tear-off material
composition (Section 5.2): May only include: asphalt roll roofing,
cap sheets, and shingles (including underlayment). May not include
other roofing debris such as: coal tar epoxy, rubber, or other
undesirables [metal, plastic, wood, glass] Slide 98 List of Roofing
Waste Items Included for Recycling YES (Include these items):
Asphalt shingles Felt attached to shingles Slide 99 List of Roofing
Waste Items Excluded for Recycling NO (Do NOT include): Wood Metal
flashings, gutters, etc Nails (best effort) Plastic wrap, buckets
Paper waste No other garbage or trash Slide 100 Lista de material
para techos basura artculo para reciclar: Si (Incluya) No / Ningun
(No incluya) Repias Madera Papel del fietro Metal: flashings,
canales Clavos Plastico Basura de papel La otra basura Slide 101
AASHTO Specification (continued) Asbestos levels: shall be
certified to be asbestos free. (Section 5.2) (Tear-off shingles
are) construction debris and various state and local regulations
may be applicable to its use. The user of this specification is
advised to contact state and local transportation departments and
environmental agencies to determine what additional requirements
may be necessary. (Note 2) Slide 102 AASHTO Specification
(continued) Deleterious material maximum limits (Section 8):
(material retained on the No. 4 sieve) Heavy fraction = 0.50%
Lightweight fraction = 0.05% Slide 103 Missouri Shingle Spec
Extrinsic Material Allowance Raised 3.0% Total 1.5% Wood Slide 104
NCHRP Rpt. 452 Incorporation of RAP in the Superpave System 15%
RAP, Assess the Effect of RAS on the Virgin Binder The Draft AASHTO
specification recommends a similar approach. < 5% RAS, no change
in PG Grade > 5% RAS, Assess the Effects of RAS on the Virgin
Binder (Justus, September 2004) Slide 105 Design Approach >5%
RAS Extract Shingle Binder from RAS Determine PG Grade of Shingle
Binder Evaluate effect of Shingle Binder on Virgin Binder Use PP28
Volumetric Mix Design for HMA Determine Optimum Asphalt Content 6-5
(Justus, September 2004) Slide 106 What happens to RAS in Virgin
Binder RAS binder dissolves into virgin binder RAS binder partially
dissolves into virgin binder RAS binder does not dissolve but acts
like an aggregate particle RAS binder particle absorbs volatile
oils from virgin binder Additional virgin binder needed to coat RAS
binder particle (Justus, September 2004) Slide 107 Volumetric Mix
Design of Control Mix - Determine the Optimum Virgin Binder Content
(OVB Control) Volumetric Mix Design of Mixture with RAS -Determine
the Optimum Virgin Binder Content (OVB RAS Mix) Contribution of RAS
Binder to Total Binder in HMA 6-7 (Justus, September 2004) Slide
108 Determine the Effect of RAS on PG Grade Binder NCHRP No. 452
presents: Mathematical Solution Graphical Solution 6-8 (Justus,
September 2004) Slide 109 Graphical Solution for PG Binder
Determine performance temperature for RAS binder Use monograph to
evaluate effect on virgin binder 6-9 (Justus, September 2004) Slide
110 Comprehensive Quality Control Plan Quality control of supply
Worker safety and health protection Final product quality, storage
and handling Shingle recycling system design Final product sampling
and lab testing Slide 111 Minnesota DOT France Avenue, Bloomington,
Mn June 2002 Demonstration Project Project Characteristics: 25,000
ADT Original Construction in 1963 Reconstruction in 1989 Shingle
Mix Overlay in 2002 (Justus, September 2004) Slide 112 Minnesota
DOT Overlay Construction Plan: 550 foot Four Lane Roadway
Northbound Lane Repaved with 5% Manufacturing Waste Shingle
Southbound Lane Repaved without Shingle (Justus, September 2004)
Slide 113 Minnesota DOT Specified Binder PG 58-28 Control Mix (30%
RAP with No Shingles): PG 67.6-27.0 PG 68.1-27.9 RAS Mix (25% RAP,
5% Shingles) PG 66.5-27.9 PG 67.6-28.4 Slide 114 Minnesota DOT
MnDOT Conclusions: Constructability of RAS Equivalent to RAP Two
Year performance of RAS Equivalent to Control PG Binder Performance
(Justus, September 2004) Slide 115 Mn/DOT Spec Maximum 5%
manufacturers shingle scrap in HMA Considered a type of RAP
Example: 5% shingles + 25% RAP = 30% max RAP QA/QC standards apply
(blending charts) Slide 116 Mn/DOT Spec on File Gradation of RAS
100% passing the sieve, and 95% passing the #4 sieve Shingles
stockpiled separately Pre-blending is prohibited Crushed &
recycled shingles introduced with RAP at same time Slide 117 Mn/DOT
Spec on File (See SWMCB handouts of March 4, 2004) Certification
from: Manufacturer Processor Sample for review List of pre-approved
sources and processors from MN/DOT Slide 118 Asbestos Risk
Incidence of asbestos is extremely low Average content was only:
0.02% in 1963 0.00016% in 1973 Source: NAHB, 1999 Slide 119 ASRAS
Data Iowa (1,791 samples), no hits Maine (118 samples), no hits
Mass: (2,288 composite samples) 11 hits < 1% (69 tarpaper
samples) 2 < 5% (109 ground RAS samples) 2 < 1% Florida (287
samples), 2 hits > 1% Source: Paul Ruesch, April 13, 2003. Slide
120 ASRAS Data (continued) Missouri (6 samples), no hits Hawaii
(100 samples), 1 hit > 1% Minnesota (156 samples), no hits
Minnesota (50 tarpaper), 1 hit @ 2% - 5% We still want more data!
(for EPA / CMRA project.) Original source: Paul Ruesch, April 13,
2003. Slide 121 DKA / AES Fiber Tests As part of the RMRC Project:
Environmental Testing of Airborne Particles at The Shingle
Processing Plant April 2003 Slide 122 Summary Highlights Risk from
asbestos is negligible to non- existent Two rounds of sampling for
total: Dust (1999) Fibers (2002) Common sense and best management
practices can help prevent employee exposure Slide 123 Sampling
Results PEL was not exceeded Peak (excursion) levels under standard
Peak exposure during cleaning Worst case total fibers measured at
0.06 fibers per cubic centimeter (f/cc) of air Well within asbestos
PEL Slide 124 Key Conclusions 1.Previous waste sampling indicates
negligible asbestos in used asphalt roofing shingles 2.Asbestos is
more likely from commercial roofing waste, mastic, caulk or felt
3.Any new exposure to asbestos would be at shingle recycling (e.g.,
grinding) operation 4.Private, residential, shingle family homes
are exempt from NESHAP Slide 125 Key Conclusions (continued) 5.MN
OSHA sampling in 1999 indicated total dust within PEL standards
6.AES sampling in 2002 indicated total fibers within PEL standards
7.Operators can reduce employee risk to dust and fiber exposure
8.Personal respirators are probably NOT necessary Slide 126
Information Sources Slide 127 Construction Materials Recycling
Association (CMRA) Slide 128 EPA Project CMRA web page
http://www.ShingleRecycling.org William Turley, Executive Director
(630) 585-7530 [email protected] Dan Krivit and Associates
(651) 489 - 4990 [email protected] Slide 129 Equipment Vendors
www.GreenGuardian.com/pdf/shingle_vendors.pdf Slide 130 SWMCB Web
Site http://www.greenguardian.com/ business/shinglerecycling.asp
Slide 131 Recent Resources April 14, 2003 Forum web page RMRC web
page www.ShingleRecycling.org SWMCB web page OEA web page Mn/DOT
& RMRC handout packet Slide 132 States California, Minnesota,
North Carolina and Texas maintain Excellent Web Sites (Justus,
September 2004) Slide 133 Trade Groups Shingle Recycling-
University of Florida - www.shinglerecycling.org
www.shinglerecycling.org Asphalt Recycling and Reclaiming
[email protected]@arra.org
Construction Materials Recycling Association- www.cdrecycling.org
(Justus, September 2004) Slide 134 Summary Slide 135 Current Trends
and Future Growth Virgin asphalt is expensive, tipping fees are
rising, improved economics Applications other than HMA are being
developed Use of post consumer shingle waste is promising Slide 136
National Asphalt Price Trend Source: U.S. Dept. of Labor: Bureau of
Labor Statistics Slide 137 Shingles Recycling into HMA is a Proven
Technology History of experience: Private operators State engineers
Environmental regulators Substantial body of literature High
quality HMA can be maintained Slide 138 Quality Control = Savings
QA/QC critical Use in HMA can be very cost effective: Cheaper
alternative to landfilling $0.50 to $3.30 per ton of HMA Slide 139
Quality Specs: Scrap Feedstock and Final Products Free of debris /
trash / foreign matter Tear-off scrap must be asphalt shingles only
No nails! Slide 140 Certification and Inspection of Shingle Supply
Clear written spec for acceptable material Certify suppliers State
licensed asbestos inspectors Visual screening of all shingle scrap
Types of shingles I.d. non-shingle waste I.d., layers, composites,
thickness, etc. Source: Paul Ruesch, April 13, 2003. Slide 141
Model Sampling Protocol (if required) Specified sampling frequency
of incoming loads Sampling of recycled asphalt shingles (ground /
screened product) Willingness to certify quality of finished
products Source: Paul Ruesch, April 13, 2003. Slide 142 Proposed
Tear-Off Supplier Certification Form .. We . certify that: All
tear-off shingle scrap came from residential buildings having four
or fewer dwelling units; and These residential buildings are not
regulated facilities according to state and federal rules; and The
material delivered consists of asphalt shingles only and contains
no known hazardous material. Slide 143 Proposed Tear-Off Processor
Certification Form .. We . certify that: All tear-off shingle scrap
came from certified suppliers only (see Supplier Certification
forms); and The final product contains no known hazardous material.
Slide 144 Strategy Identify players Pre-meeting Identify unknowns
Request demonstration project Source: Paul Ruesch, April 13, 2003.
Slide 145 Minnesota Approach Regulatory status under NESHAP: Single
family shingle scrap only (no commercial or institutional
buildings) No testing required if certified as free of asbestos
Source: Dan Krivit, Overcoming the Barriers to Asphalt Shingle
Recycling, Environmental White Paper Report, Mn/DOT, April 2003.
Slide 146 Key Conclusions 1. Proven and documented 2. Quality
control is essential 3. Economics are driving the market 4.
Manufacturer shingle scrap recycling is here today and
commercialized 5. Tear-off shingle scrap is under development, but
feasible Slide 147 Recommendations 1.CONTINUE MARKET DEVELOPMENT:
Cities, counties and states should use alternate bid language
allowing shingles EPA / CMRA project in progress: Asbestos
statistics Best practices guideline documents Implementation /
Outreach Slide 148 Recommendations (Continued) 2.MANAGE the
asbestos issue: Restrict supply to private, residential homes only
(per NESHAP) Tight supply specification Certify suppliers (e.g.,
roofing companies) Inspect each load (suggest becoming a licensed
inspector) Slide 149 Recommendations (Continued) 3.PROTECT employee
health and safety: Develop dust management program Develop employee
hazard prevention Shroud grinder Water scrap shingles Provide
accurate information as part of a full employee education program
Slide 150 Recommendations (Continued) 4.GUARANTEE YOUR PRODUCT
QUALITY: Asbestos free No nails (use multiple magnets) - inch minus
Controlled mix ratios Exceed State QA/QC procedures
