Fiber Additives in Asphalt Mixtures (2015)

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48 APPENDIX C Tabulated Survey Responses 1 Does your organization currently specify or allow the use of fibers in asphalt mixes? TABLE C1 DOES YOUR ORGANIZATION CURRENTLY SPECIFY OR ALLOW THE USE OF FIBERS IN ASPHALT MIXES? Yes No AL, CO, CT, DE, FL, GA, ID, IL, IN, KS, KY, LA, MD, ME, MI, MS, MO, NC, NH, NJ, NY, OH, OK, ON, OR, SC, SD, TN, TX, VA, WI AK, AR, AZ, CA, CO, HI, IA, MI, MN, MT, ND, NM, NV, PA, RI, UT, WA, WV, WY 2. In which applications do you specify/allow the use of fibers in asphalt mixtures? TABLE C2 IN WHICH APPLICATIONS DO YOU SPECIFY/ALLOW THE USE OF FIBERS IN ASPHALT MIXTURES? State/ Province SMA or Gap-Graded Porous or Open-Graded Both SMA and Porous HMA Overlays Other AL • CO • CT • Cold mix DE • FL • GA • ID HMA overlays IL • IN • KS • KY • LA • MD • ME • MI • MO • MS • NC • Has SMA spec, but has not placed any. NH • Curb mixtures NJ • NY • OH • Supplemental spec for districts desiring to use. OK • ON • Have specified on trial mixes designed to better resist cracking. OR • SC • SD • TN • TX • VA • Thin HMA overlays, stabilized mixtures WI •

49 3. Approximately how many tons of asphalt mix containing fibers are used each year? -- No response. TABLE C3 APPROXIMATELY HOW MANY TONS OF ASPHALT MIX CONTAINING FIBERS ARE USED EACH YEAR? State/Province Approximate Tonnage Comment AL Not tracked. CO — CT 1,500 DE 20,000 FL 500,000 GA 208,586 ID Unknown. Very few. IL Minimal with current use of RAS and GTR. IN Unknown. KS 10,000 KY 50,000–100,000 LA Not available. MD 500,000 ME <1,000 MI — MO 396,379 in 2012; 10,212 in 2013 MS — NC 60,000 NH <5,000 NJ 100,000 NY <2,000 OH <10,000 OK 20,500 ON Average 10,000 per year 2010–2013; 60,000 in 2014 SMA pause lifted for 2014. OR Under 500 Before 2009, approx. 30,000. SC 250,000 SD 100,000–150,000 TN 135,000 in 2013; 197,000 in 2012 In OGFC. No SMA placed for last 4–5 yrs. TX 700,000 VA — WI Unknown

50 4. Did your organization use fibers in the past and discontinue use in some or all applications? (Asked only of states that do not currently use fibers.) TABLE C4 DID YOUR ORGANIZATION USE FIBERS IN THE PAST AND DISCONTINUE USE IN SOME OR ALL APPLICATIONS? State/Province No Yes Not sure Comments AK • AR • AZ • Fibers were used in SMA to prevent draindown but not currently using SMA. CA • HI • IA • MB • MN • MT • ND • NM • Used to use in SMA but have not placed SMA since at least 2000. NV • PA • Researching use of fibers through 12 current pilot projects (polyester and aramid). RI • UT • WA • WV • WY • Asked only of states that indicated they do not currently use fibers.

51 5. What types of fibers does/did your organization specify or allow for various applications? (Click all that apply.) TABLE C5 WHAT TYPES OF FIBERS DOES/DID YOUR ORGANIZATION SPECIFY OR ALLOW FOR VARIOUS APPLICATIONS? State/Province Fiber Types Specified Fiber Types Allowed Comments AL Polymer, cellulose, mineral CT Polymer Unspecified fibers required DE Cellulose, mineral FL Cellulose, mineral GA Cellulose, mineral Polymer (experimentally) ID Polymer IL Cellulose, mineral Cellulose, mineral IN Cellulose, mineral KS Cellulose, mineral KY Cellulose, mineral LA Cellulose, mineral MD Polymer, cellulose, mineral ME Cellulose, mineral MI Cellulose MO Cellulose, mineral MS Cellulose, mineral NC Cellulose, mineral NH Polymer (polyester) NJ Cellulose, mineral NY Polymer, mineral OH Polymer Cellulose, mineral OK Cellulose ON Cellulose, mineral Cellulose, mineral, manufactured shingle material Polyethylene terephthalate OR Cellulose, mineral SC Cellulose, mineral Cellulose, mineral SD Cellulose TN Cellulose Cellulose TX Cellulose Polymer, cellulose VA Cellulose Polymer WI Polymer, cellulose

52 6. Why does your organization use fibers? (Click all that apply.) TABLE C6 WHY DOES YOUR ORGANIZATION USE FIBERS? State/ Province To Prevent Draindown To Improve Cracking Resistance To Improve Rutting Resistance Other AL • CO • CT • DE • FL • GA • • • ID • • IL • IN • KS • KY • LA • MD • • • Allows more binder in mix ME • MI • MO • MS • NC • NH • • NJ • NY • OH • • OK • • • Increase mastic content ON • • OR • SC • SD • TN • • • TX • VA • • • WI • 7. Does your organization have any specification, test methods, mix design methods, or acceptance criteria for fibers or fiber-modified mixtures? TABLE C7 DOES YOUR ORGANIZATION HAVE ANY SPECIFICATION, TEST METHODS, MIX DESIGN METHODS, OR ACCEPTANCE CRITE- RIA FOR FIBERS OR FIBER-MODIFIED MIXTURES? Yes No AL, DE, FL, GA, IL, KS, KY, MD, ME, MO, NC, NH, NJ, NY, OH, ON, OR, SC, SD, TN, TX, VA, WI CT, ID, IN, LA, MS, OK

53 8. Which properties do you measure/control? TABLE C8 WHICH PROPERTIES DO YOU MEASURE/CONTROL? Yes No AL Draindown (AASHTO T 305). DE Cellulose: ash content (D1282); pH, moisture content, and length (AASHTO MP 8). Mineral (from virgin basalt, diabase, slag, or other silaceous rock): length and thickness (MP 8), shot content (ASTM C612). FL Mineral (from virgin basalt, diabase, or slag) with cationic sizing agent for dispersal and adhesion: specified length, thickness, shot con- tent (ASTM C612). Cellulose: length, sieve analysis (Alpine or Ro-Tap methods), ash content, pH, oil absorption, moisture content. Certified test results required for each batch. GA Draindown, wet mixing time. Polymer: limit on unseparated fibers, length, form, specific gravity, tensile strength, melt temperature, acid/ alkali resistance, packaging. Cellulose: ash content, pH, moisture content. Cellulose pellets: pellet diameter, binder type and content. Mineral (from virgin basalt, diabase, slag, or other silicate rock): shot content. IL Sieve analysis, length, ash content, pH, oil absorption, moisture content, shot content/gradation. KS Draindown (KT-63). KY Reference AASHTO M325 for design of SMA. Material certification to verify cellulose or mineral fibers. Dosage rate specified. MD Draindown, percent stabilizer. ME Cellulose: Alpine sieve analysis, ash content, pH, oil absorption, moisture content. Mineral: dosage rate, length, thickness, shot content. MO Draindown (T 305). NC Mineral (from virgin basalt, diabase, or slag) with cationic sizing agent for dispersal and adhesion: specified length, thickness, shot con- tent (ASTM C612), degradation (GDT-124/McNett fractionation). Cellulose: Fiber length, sieve analysis (Alpine or Ro-TAP method), ash content, pH, oil absorption, moisture content, degradation. Cellulose pellets: 50/50 blend of cellulose fiber and asphalt binder; fiber to conform to cellulose requirements above, pellet size, asphalt penetration. NH Polyester fibers from Qualified Products List, uniformly distributed in dry mix at ~0.25% of total batch weight. NJ Mineral or cellulose fibers conforming to AASHTO MP 8. Dosage rate specified. Fibers must be dispersed uniformly and proportioned to within ±10% of required rate. Certification required. Manufacturer’s representative present for first day of production. NY Mineral: length, thickness, shot content. OH For SMA–cellulose: length, sieve analysis (Alpine or Ro-Tap), ash content, pH, oil absorption, moisture content. Cellulose pellets: cellulose fiber requirements above, pellet size, binder penetration. Mineral (from virgin basalt, diabase, or slag with cationic sizing agent for dispersal and adhesion): length, thickness, shot content, degradation. For supplemental specification for rut-resistant mix: polyester or polypropylene from Qualified Products List: denier, length, crimps, ten- sile strength, specific gravity, melt temperature, certified test results. ON Cellulose: sieve analysis (Alpine or mesh screen), length, ash content, pH, oil absorption, moisture content. Mineral: length, thickness, shot content. OR Mineral: mineral (from virgin basalt, diabase, or slag): dosage rate, length, minimum and maximum thickness, shot content (ASTM C612). Cellulose: dosage rate, length, gradation (Alpine or mesh screen), ash content, pH, oil absorption, moisture content. SC Draindown (SC-T-90, SC-T-91). SD Draindown (at design and once a day during production). Cellulose: length, sieve analysis (Alpine), ash content, pH, oil absorption, moisture content. TN Draindown (T 305). TX Draindown. VA Cellulose or mineral with supplier’s certification of properties and documented success in similar applications. WI Draindown.

54 9. Are you aware of/does your organization practice or enforce any safety/health/environmental restrictions when fibers are used in asphalt mixtures? TABLE C9 ARE YOU AWARE OF/DOES YOUR ORGANIZATION PRACTICE OR ENFORCE ANY SAFETY/HEALTH/ENVIRONMENTAL RESTRICTIONS WHEN FIBERS ARE USED IN ASPHALT MIXTURES? Yes No Rely on Manufacturers’ Recommendations None CT, KS, KY, MD, ME, NH, OK, ON, SD, TN, VA, WI AL, DE, FL, GA, ID, IL, IN, LA, MO, MS, NC, NJ, NY, OH, ON, OR, SC, TX 10. Does your organization have any current or completed research of performance histories on fiber-modified asphalt mixtures? TABLE C10 DOES YOUR ORGANIZATION HAVE ANY CURRENT OR COMPLETED RESEARCH OF PERFORMANCE HISTORIES ON FIBER- MODIFIED ASPHALT MIXTURES? Yes No FL, GA, ID,* MD, MO, NJ, ON AL, CT, DE, IL, IN, KS, KY, LA, ME, MS, NC, NH, NY, OH, OK, OR, SC, SD, TN, TX,VA, WI 11. Does your organization have information on costs (initial or life cycle) of fibers or benefit–cost ratios for fiber-modified mixtures? TABLE C11 DOES YOUR ORGANIZATION HAVE INFORMATION ON COSTS (INITIAL OR LIFE CYCLE) OF FIBERS OR BENEFIT–COST RATIOS FOR FIBER-MODIFIED MIXTURES? Yes No SD AL, CT, DE, IL, IN, KS, KY, LA, ME, MS, NC, NH, NY, OH, OK, OR, SC, SD, TN, TX,VA, WI

55 12. Do you have any additional information, current or historical, that you would like to share? (Asked of all.) TABLE C12 DO YOU HAVE ANY ADDITIONAL INFORMATION, CURRENT OR HISTORICAL, THAT YOU WOULD LIKE TO SHARE? State/ Province Comment AK We are experiencing shorter than normal life expectancy out of our OGFC pavements. We have experimented using WMA (Evotherm) and GTR to remove fibers from OGFC pavements to improve mixture consistency and overall constructability of these pavements. We have also looked into possibly using a finer 9.5 mm gradation using 789 stone in lieu of the 12.5 mm design using mostly # 7 stone to improve durability. CO The only fibers currently allowed are in our SMA mix, to prevent draindown. FL We have only ever used fibers in open-graded friction courses, with the purpose to reduce binder draindown. We have been using them since the late 1990s. While our specifications allow either mineral or cellulose fibers, about 99% of our experience is with mineral fibers. HI We have used fibers in SMA mixes—one project in 2004 and one paving in a couple of months. LA Fibers have been found to be useful for the purpose specified, preventing draindown. MI We require cellulose fibers in our gap-graded mixture (SMA). In other mixes we do not allow. MO In reference to the question regarding current and completed research, please see the following. We have a few early reports looking at the implementation of the stone mastic asphalt mixtures which incorporated fibers. MT When I say we “don’t allow” I mean our specification is silent. We don’t have any language allowing or prohibiting fibers. NC NCDOT does also allow the use of recycled asphalt shingles in OGFC strictly to control asphalt draindown. If the mixture can meet draindown specifications with the sole use of shingles, no fibers are needed. NJ Can provide research reports regarding plant produced mixtures—data generated based on laboratory testing and comparisons with nonfiber mixture on same job. (Tom Bennert) OH SS 826 has been in existence for over 20 years. Some requirements in it are a result of learning what does not work. Most districts do not specify 826 because of the availability of PG modified binders that work well in most instances. In addition, we have had mixed success with 826 fiber mixes. What we found is that in high crush aggregate mixes the fibers can fall between aggregate particles, actually preventing aggregate lock. For lesser strength mixes, fibers do help though. OK We are allowing an SMA to use Evotherm rather than cellulose fibers for one project. I added 0.3% cellulose fibers to an OGFSC design for the NCAT Test Track section E1. The intent is to allow more binder to increase the mastic. A SCDOT method was used to determine binder content of 7.1%. FHWA formula for our average specific gravity results in binder contents of 5.7%–5.8% for tradi- tional OGFSC. ON We experimented with the addition of 1%–2% asbestos fibers in the mid-70s, but discontinued the use due to health and safety issues. Adopted SMA as a premium wearing course in 2002, allowing mineral and cellulose fibers. The addition of roof shingle tabs (which was also a source of fiber) was permitted. SMA quantities were around 75–100 K tonnes. The use of SMA was paused in 2006/07 due to early age friction issues. It has now been reinstated. Other fibers have been trialed, including polymer and PET fibers in Superpave 19.0 and SMA to evaluate mitigation of reflection cracking from the underlying concrete pavement. Performance is being monitored. OR The use of open-graded mixes in Oregon was all but eliminated after examining life cycle cost for open-graded mixtures in 2008. As this was the only mixture [in which] Oregon was using fibers, their use has also significantly been reduced. There may be an increase in the future of porous asphalt use for runoff mitigation, which may lead to an increase in the use of fibers again. PA We are going to summarize testing results by the end of 2014; I can provide them when we have them. SC We are experiencing shorter than normal life expectancy out of our OGFC pavements. We have experimented using WMA (Evotherm) and GTR to remove fibers from OGFC pavements to improve mixture consistency and overall constructability of these pavements. We have also looked into possibly using a finer 9.5mm gradation using 789 stone in lieu of the 12.5mm design using mostly # 7 stone to improve durability. WA Our only experience with fibers (cellulose) has been on a couple of SMA trial projects constructed several years ago WV We have been open to vendors showing us the products but have not implemented the use of fiber in our asphalt mixes.

NEED SPINE WIDTH Abbreviations used without definitions in TRB publications: A4A Airlines for America AAAE American Association of Airport Executives AASHO American Association of State Highway Officials AASHTO American Association of State Highway and Transportation Officials ACI–NA Airports Council International–North America ACRP Airport Cooperative Research Program ADA Americans with Disabilities Act APTA American Public Transportation Association ASCE American Society of Civil Engineers ASME American Society of Mechanical Engineers ASTM American Society for Testing and Materials ATA American Trucking Associations CTAA Community Transportation Association of America CTBSSP Commercial Truck and Bus Safety Synthesis Program DHS Department of Homeland Security DOE Department of Energy EPA Environmental Protection Agency FAA Federal Aviation Administration FHWA Federal Highway Administration FMCSA Federal Motor Carrier Safety Administration FRA Federal Railroad Administration FTA Federal Transit Administration HMCRP Hazardous Materials Cooperative Research Program IEEE Institute of Electrical and Electronics Engineers ISTEA Intermodal Surface Transportation Efficiency Act of 1991 ITE Institute of Transportation Engineers MAP-21 Moving Ahead for Progress in the 21st Century Act (2012) NASA National Aeronautics and Space Administration NASAO National Association of State Aviation Officials NCFRP National Cooperative Freight Research Program NCHRP National Cooperative Highway Research Program NHTSA National Highway Traffic Safety Administration NTSB National Transportation Safety Board PHMSA Pipeline and Hazardous Materials Safety Administration RITA Research and Innovative Technology Administration SAE Society of Automotive Engineers SAFETEA-LU Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (2005) TCRP Transit Cooperative Research Program TEA-21 Transportation Equity Act for the 21st Century (1998) TRB Transportation Research Board TSA Transportation Security Administration U.S.DOT United States Department of Transportation r i ti it t fi iti i li ti : irli f r ri ri i ti f ir rt ti ri i ti f t t i ffi i l ri i ti f t t i r rt ti ffi i l I ir rt il I t r ti l rt ri ir rt r ti r r r ri it i iliti t ri li r rt ti i ti ri i t f i il i r ri i t f i l i r ri i t f r ti t ri l ri r i i ti it r rt ti i ti f ri r i l r f t t i r r rt t f l rit rt t f r ir t l r t ti r l i ti i i tr ti r l i i i tr ti r l t r rri r f t i i tr ti r l ilr i i tr ti r l r it i i tr ti r t ri l r ti r r r I I tit t f l tri l l tr i i r I I t r l rf r rt ti ffi i t f I I tit t f r rt ti i r - i f r r r i t t t r t ( ) ti l r ti i i tr ti ti l i ti f t t i ti ffi i l ti l r ti r i t r r r ti l r ti i r r r ti l i r ffi f t i i tr ti ti l r rt ti f t r i li r t ri l f t i i tr ti I r I ti l i i tr ti i t f t ti i r - f , t l , l i l , ffi i t r rt ti it t: f r r ( ) r it r ti r r r - r rt ti it t f r t t t r ( ) r rt ti r r r rt ti rit i i tr ti . . it t t rt t f r rt ti

92+ pages; Perfect Bind with SPINE COPY = 14 pts Fiber Additives in Asphalt Mixtures NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM NCHRP SYNTHESIS 475 NEED SPINE WIDTH Job No. XXXX Pantone 202 C TRANSPORTATION RESEARCH BOARD 500 F ifth S treet, N .W . W ashing to n, D .C . 20001 A D D R ESS SER VICE R EQ UESTED A Synthesis of Highway Practice